Sample records for zebra mussel populations

  1. Use of on-site refugia to protect unionid populations from zebra mussel-induced mortality

    USGS Publications Warehouse

    Nichols, S. Jerrine; Black, M. Glen; Allen, Jeffrey D.

    2000-01-01

    Protecting unionid populations as zebra mussels spread into inland waterways has relied mainly on relocating at-risk animals into aquaculture facilities. While such relocations are the only viable management technique for some populations, facility availability is limited, leaving many unionids facing extirpation. Another management strategy is in-situ protection either by enhancing natural refugia or by creating managed refugia. We have reviewed all reports of natural refugia and found that refugia for unionids can be found in many areas. There are many habitats where zebra mussel colonization has been limited, or of a temporary nature. Within zebra mussel infested areas, unionid communities continue to survive in some shallow water sites such as estuaries, deltas, and lake-connected wetlands. Managed refugia can be created in areas where natural refugia do not exist. We present a case study on recent efforts to create refugia in an area with rapidly expanding zebra mussel populations. Preliminary analysis of unionid body condition indicates that removal of encrusted zebra mussels only once a year can improve unionid condition factors and decrease mortality. Natural and managed refugia can provide an additional conservation management option in some areas.

  2. USGS Zebra Mussel Monitoring Program for north Texas

    USGS Publications Warehouse

    Churchill, Christopher J.; Baldys, Stanley

    2012-01-01

    The U.S. Geological Survey (USGS) Zebra Mussel Monitoring Program for north Texas provides early detection and monitoring of zebra mussels (Dreissena polymorpha) by using a holistic suite of detection methods. The program is designed to assess zebra mussel occurrence, distribution, and densities in north Texas waters by using four approaches: (1) SCUBA diving, (2) water-sample collection with plankton tow nets (followed by laboratory analyses), (3) artificial substrates, and (4) water-quality sampling. Data collected during this type of monitoring can assist rapid response efforts and can be used to quantify the economic and ecological effects of zebra mussels in the north Texas area. Monitoring under this program began in April 2010. The presence of large zebra mussel populations often causes undesirable economic and ecological effects, including damage to water-processing infrastructure and hydroelectric powerplants (with an estimated 10-year cost of $3.1 billion), displacement of native mussels, increases in concentrations of certain species of cyanobacteria, and increases in concentrations of geosmin (an organic compound that results in taste and odor issues in water). Since no large-scale, environmentally safe eradication method has been developed for zebra mussels, it is difficult to remove established populations. Broad physicochemical adaptability, prolific reproductive capacity, and rapid dispersal methods have enabled zebra mussels, within a period of about 20 years, to establish populations under differing environmental conditions across much of the eastern part of the United States. In Texas, the presence of zebra mussels was first confirmed in April 2009 in Lake Texoma in the Red River Basin along the Texas-Oklahoma border. They were most likely introduced into Lake Texoma through overland transport from an infested water body. Since then, the presence of zebra mussels has been reported in both the Red River and Washita River arms of Lake Texoma, in

  3. Zebra mussel infestation of unionid bivalves (Unionidae) in North America

    USGS Publications Warehouse

    Schloesser, Don W.; Nalepa, Thomas F.; Mackie, Gerald L.

    1996-01-01

    In 1989, zebra mussels received national attention in North America when they reached densities exceeding 750,000/m2 in a water withdrawal facility along the shore of western Lake Erie of the Laurentian Great Lakes. Although water withdrawal problems caused by zebra mussels have been of immediate concern, ecological impacts attributed to mussels are likely to be the more important long-term issue for surface waters in North America. To date, the epizoic colonization (i.e., infestation) of unionid bivalve mollusks by zebra mussels has caused the most direct and severe ecological impact. Infestation of and resulting impacts caused by zebra mussels on unionids in the Great Lakes began in 1988. By 1990, mortality of unionids was occurring at some locations; by 1991, extant populations of unionids in western Lake Erie were nearly extirpated; by 1992, unionid populations in the southern half of Lake St. Clair were extirpated; by 1993, unionids in widely separated geographic areas of the Great Lakes and the Mississippi River showed high mortality due to mussel infestation. All infested unionid species in the Great Lakes (23) have become infested and exhibited mortality within two to four years after heavy infestation began. Data indicate that mean zebra mussel densities >5,000–6,000/m2 and infestation intensities >100-200/unionid in the presence of heavy zebra mussel recruitment results in near total mortality of unionids. At present, all unionid species in rivers, streams, and akes that sympatrically occur with zebra mussels have been infested and, in many locations, negatively impacted by zebra mussels. We do not know the potential consequences of infestation on the 297 unionid species found in North America, but believe zebra mussels pose an immediate threat to the abundance and diversity of unionids.

  4. Review of techniques to prevent introduction of zebra mussels (Dreissena polymorpha) during native mussel (Unionoidea) conservation activities

    USGS Publications Warehouse

    Cope, W.G.; Newton, T.J.; Gatenby, C.M.

    2003-01-01

    Because of the declines in diversity and abundance of native freshwater mussels (superfamily Unionoidea), and the potential decimation of populations of native mussels resulting from the rapid spread of the exotic zebra mussel Dreissena polymorpha, management options to eliminate or reduce the threat of the zebra mussel are needed. Relocating native mussels to refugia (artificial and natural) has been proposed to mitigate the threat of zebra mussels to native species. Relocation of native mussels to refugia such as fish hatchery facilities or natural habitats within their historic range. Which are unlikely to be infested by zebra mussels, necessitates that protocols be developed to prevent the inadvertent introduction of zebra mussels. Several recent studies have developed Such protocols, and have assessed their effectiveness on the health and survival of native mussels during subsequent relocation to various refugia. The purpose of this project is to synthesize and evaluate the current protocols and to develop a set of procedures that resource managers and researchers should consider before conducting conservation activities in zebra mussel infested waters. We found that the existing protocols have many common points of concern, such as facility modification and suitability, zebra mussel risk assessment and management procedures, and health and disease management procedures. These conservation protocols may have broad applicability to other situations and locations. A summary and evaluation of the information in these main areas, along with recommended guidelines, are presented in this article.

  5. Habitat shift in invading species: Zebra and quagga mussel population characteristics on shallow soft substrates

    USGS Publications Warehouse

    Berkman, P.A.; Garton, D.W.; Haltuch, M.A.; Kennedy, G.W.; Febo, L.R.

    2000-01-01

    Unexpected habitat innovations among invading species are illustrated by the expansion of dreissenid mussels across sedimentary environments in shallow water unlike the hard substrates where they are conventionally known. In this note, records of population characteristics of invading zebra (Dreissena polymorpha) and quagga (Dreissena bugensis) mussels from 1994 through 1998 are reported from shallow (less than 20 m) sedimentary habitats in western Lake Erie. Haphazard SCUBA collections of these invading species indicated that combined densities of zebra and quagga mussels ranged from 0 to 32,500 individuals per square meter between 1994 and 1998, with D. polymorpha comprising 75-100% of the assemblages. These mixed mussel populations, which were attached by byssal threads to each other and underlying sand-grain sediments, had size-frequency distributions that were typical of colonizing populations on hard substrates. Moreover, the presence of two mussel cohorts within the 1994 samples indicated that these species began expanding onto soft substrates not later than 1992, within 4 years of their initial invasion in western Lake Erie. Such historical data provide baselines for interpreting adaptive innovations, ecological interactions and habitat shifts among the two invading dreissenid mussel species in North America.

  6. Molecular ecology of zebra mussel invasions.

    PubMed

    May, Gemma E; Gelembiuk, Gregory W; Panov, Vadim E; Orlova, Marina I; Lee, Carol Eunmi

    2006-04-01

    The invasion of the zebra mussel, Dreissena polymorpha, into North American waters has resulted in profound ecological disturbances and large monetary losses. This study examined the invasion history and patterns of genetic diversity among endemic and invading populations of zebra mussels using DNA sequences from the mitochondrial cytochrome oxidase I (COI) gene. Patterns of haplotype frequency indicate that all invasive populations of zebra mussels from North America and Europe originated from the Ponto-Caspian Sea region. The distribution of haplotypes was consistent with invasive populations arising from the Black Sea drainage, but could not exclude the possibility of an origin from the Caspian Sea drainage. Similar haplotype frequencies among North American populations of D. polymorpha suggest colonization by a single founding population. There was no evidence of invasive populations arising from tectonic lakes in Turkey, while lakes in Greece and Macedonia contained only Dreissena stankovici. Populations in Turkey might be members of a sibling species complex of D. polymorpha. Ponto-Caspian derived populations of D. polymorpha (theta = 0.0011) and Dreissena bugensis (one haplotype) exhibited low levels of genetic diversity at the COI gene, perhaps as a result of repeated population bottlenecks. In contrast, geographically isolated tectonic lake populations exhibited relatively high levels of genetic diversity (theta = 0.0032 to 0.0134). It is possible that the fluctuating environment of the Ponto-Caspian basin facilitated the colonizing habit of invasive populations of D. polymorpha and D. bugensis. Our findings were concordant with the general trend of destructive freshwater invaders in the Great Lakes arising from the Ponto-Caspian Sea basin.

  7. Predation on exotic zebra mussels by native fishes: Effects on predator and prey

    USGS Publications Warehouse

    Magoulick, D.D.; Lewis, L.C.

    2002-01-01

    mussel colonisation, but are ultimately unlikely to limit population density because of zebra mussel reproductive potential.

  8. Comparative biology of zebra mussels in Europe and North America: an overview

    USGS Publications Warehouse

    Mackie, Gerald L.; Schloesser, Don W.

    1996-01-01

    SYNOPSIS. Since the discovery of the zebra mussel, Dreissena polymorpha, in the Great Lakes in 1988 comparisons have been made with mussel populations in Europe and the former Soviet Union. These comparisons include: Population dynamics, growth and mortality rates, ecological tolerances and requirements, dispersal rates and patterns, and ecological impacts. North American studies, mostly on the zebra mussel and a few on a second introduced species, the quagga mussel, Dreissena bugensis, have revealed some similarities and some differences. To date it appears that North American populations of zebra mussels are similar to European populations in their basic biological characteristics, population growth and mortality rates, and dispersal mechanisms and rates. Relative to European populations differences have been demonstrated for: (1) individual growth rates; (2) life spans; (3) calcium and pH tolerances and requirements; (4) potential distribution limits; and (5) population densities of veligers and adults. In addition, studies on the occurrence of the two dreissenid species in the Great Lakes are showing differences in their modes of life, depth distributions, and growth rates. As both species spread throughout North America, comparisons between species and waterbodies will enhance our ability to more effectively control these troublesome species.

  9. Development of a molecular diagnostic system to discriminate Dreissena polymorpha (zebra mussel) and Dreissena bugensis (quagga mussel)

    USGS Publications Warehouse

    Hoy, M.S.; Kelly, K.; Rodriguez, R.J.

    2010-01-01

    A 3-primer PCR system was developed to discriminate invasive zebra (Dreissena polymorpha) and quagga (Dreissena bugensis) mussel. The system is based on: 1) universal primers that amplifies a region of the nuclear 28s rDNA gene from both species and 2) a species-specific primer complementary to either zebra or quagga mussel. The species-specific primers bind to sequences between the binding sites for the universal primers resulting in the amplification of two products from the target species and one product from the nontarget species. Therefore, nontarget products are positive amplification controls. The 3-primer system accurately discriminated zebra and quagga mussels from seven geographically distinct populations.

  10. Evaluation of several chemical disinfectants for removing zebra mussels from unionid mussels

    USGS Publications Warehouse

    Waller, D.L.; Fisher, S.W.

    1998-01-01

    We evaluated the safety and effectiveness of chemical treatments for killing veliger and juvenile stages of the zebra mussel Dreissena polymorpha attached to unionid mussels. Static toxicity tests were conducted on eight unionid mussel species with common aquaculture chemicals (benzalkonium chloride, formalin, hydrogen peroxide, calcium chloride, potassium chloride, and sodium chloride). The concentration and duration of each chemical treatment tested had previously been found to kill zebra mussel veligers and juveniles. Several species (e.g., Elliptio dilatata, Lampsilis cardium, and Lasmigona complanata) incurred less than 10% mortality in chloride salt treatments, while in other species (e.g., Obliquaria reflexa and Leptodea fragilis) mortality varied greatly among treatment regimes. Treatments with benzalkonium chloride, formalin, and hydrogen peroxide were less than 90% effective on juvenile stages of zebra mussels and, therefore, were ruled out after preliminary trials. Limited application of specific chemical treatments may be feasible for more tolerant species; however, effective disinfection of unionid shells will require the use of chemical treatment followed by a quarantine period to completely remove zebra mussel larvae and juveniles.

  11. Zebra mussels invade Lake Erie muds

    USGS Publications Warehouse

    Berkman, Paul Arthur; Haltuch, Melissa A.; Tichich, Emily; Garton, David W.; Kennedy, Gregory W.; Gannon, John E.; Mackey, Scudder D.; Fuller, Jonathan A.; Liebenthal, Dale L.

    1998-01-01

    Zebra mussels (Dreissena polymorpha) originated in western Russia but have now become widespread in Europe and North America. They are widely known for their conspicuous invasion of rocks and other hard substrates in North American and European watersheds. We have found beds of zebra mussels directly colonizing sand and mud sediments each year across hundreds of square kilometres of North America's Lake Erie. This transformation of sedimentary habitats into mussel beds represents an unforeseen change in the invasive capacity of this species.

  12. Crayfish (Orconectes virilis) predation on zebra mussels (Dreissena polymorpha)

    USGS Publications Warehouse

    Love, Joy; Savino, Jacqueline F.

    1993-01-01

    In laboratory studies, we quantified predation rates and handling time of crayfish (Orconectes virilis) on zebra mussels (Dreissena polymorpha) and rainbow trout (Oncorhhynchus mykiss) eggs. In single prey species tests, crayfish ate zebra mussels at similar rates as they ate rainbow trout eggs. When both prey were present, crayfish preferred rainbow trout eggs. Handling time of mussels was about twice that of rainbow trout eggs, and energetic content of mussels was lower. Therefore, net benefit for foraging on rainbow trout eggs was about three times that of foraging on zebra mussels.

  13. How well can fishes prey on zebra mussels in eastern North America?

    USGS Publications Warehouse

    French, John R. P.

    1993-01-01

    Literature on mollusk-eating fishes was reviewed to determine the potential for different species of fish to control zebra mussels in eastern North America. At least six species are potential predators of zebra mussels because they possess (1) both upper and lower pharyngeal teeth or (2) lower pharyngeal teeth and chewing pads located on the dorsal roof for crushing mollusk shells. Freshwater drum (Aplodinotus grunniens) and two centrarchids, redear sunfish (Lepomis microlophus) and pumpkinseed (L. gibbosus), possess both upper and lower pharyngeal teeth and are likely to consume more zebra mussels than fishes with only lower pharyngeal teeth. Only two catostomid species, copper and river redhorses (Moxostoma hubbsi and M. carinatum), have chewing pads that enable them to crush mollusks. The exotic omnivorous common carp (Cyprinus carpio), possessing lower teeth and a chewing pad, may prey on zebra mussels when aquatic insect larvae, its preferred food, become rare. Managing populations of drum, sunfishes and redhorses to reduce exploitation of large individuals and improve their habitats are suggested as means to intensify biological control of zebra mussels in eastern North America. Other Eurasian molluscivores, the roach (Rutilus rutilus) and the black carp (Mylopharyngodon piceus) should not be introduced into North America because research has shown repeatedly that an introduced biological controller usually does not forage for unwanted pests or reside only in preferred habitats of pests. Drum, sunfishes and redhorses should be preferred over these exotics as biological controllers of zebra mussels in North America because these native fishes will likely occupy newly established habitats of zebra mussels.

  14. Quagga and zebra mussels: biology, impacts, and control

    USGS Publications Warehouse

    Nalepa, Thomas F.; Schloesser, Don W.; Nalepa, Thomas F.; Schloesser, Don W.

    2013-01-01

    Quagga and Zebra Mussels: Biology, Impacts, and Control, Second Edition provides a broad view of the zebra/quagga mussel issue, offering a historic perspective and up-to-date information on mussel research. Comprising 48 chapters, this second edition includes reviews of mussel morphology, physiology, and behavior. It details mussel distribution and spread in Europe and across North America, and examines policy and regulatory responses, management strategies, and mitigation efforts. In addition, this book provides extensive coverage of the impact of invasive mussel species on freshwater ecosystems, including effects on water clarity, phytoplankton, water quality, food web changes, and consequences to other aquatic fauna. It also reviews and offers new insights on how zebra and quagga mussels respond and adapt to varying environmental conditions. This new edition includes seven video clips that complement chapter text and, through visual documentation, provide a greater understanding of mussel behavior and distribution.

  15. New Concerns Emerge as Zebra Mussel Spreads.

    ERIC Educational Resources Information Center

    Walter, Martha L., Ed.

    1992-01-01

    Reports on the Zebra Mussel invasion of North American inland waterways. Discusses United States Army Corps of Engineers operations that may facilitate or be affected by the spread of Zebra Mussels, the threat to native clams, chemical and mechanical control methods, natural solutions, and ongoing research. (MCO)

  16. Mortality of zebra mussel, Dreissena polymorpha, veligers during downstream transport

    USGS Publications Warehouse

    Horvath, T.G.; Lamberti, G.A.

    1999-01-01

    1. Streams flowing from lakes which contain zebra mussels, Dreissena polymorpha, provide apparently suitable habitats for mussel colonization and downstream range expansion, yet most such streams contain few adult mussels. We postulated that mussel veligers experience high mortality during dispersal via downstream transport. They tested this hypothesis in Christiana Creek, a lake-outlet stream in south-western Michigan, U.S.A., in which adult mussel density declined exponentially with distance downstream. 2. A staining technique using neutral red was developed and tested to distinguish quickly live and dead veligers. Live and dead veligers were distinguishable after an exposure of fresh samples to 13.3 mg L-1 of neutral red for 3 h. 3. Neutral red was used to determine the proportion of live veligers in samples taken longitudinally along Christiana Creek. The proportion of live veligers (mean ?? SE) declined from 90 ?? 3% at the lake outlet to 40 ?? 8% 18 km downstream. 4. Veligers appear to be highly susceptible to damage by physical forces (e.g. shear), and therefore, mortality in turbulent streams could be an important mechanism limiting zebra mussel dispersal to downstream reaches. Predictions of zebra mussel spread and population growth should consider lake-stream linkages and high mortality in running waters.

  17. Mitigation of unionid mortality caused by zebra mussel infestation: cleaning of unionids

    USGS Publications Warehouse

    Schloesser, Don W.

    1996-01-01

    Exotic zebra mussels Dreissena polymorpha have infested and caused mortality of native unionids in the Great Lakes since 1986; no other such parasitism of native unionids occurs in North America. Survival of unionids threatened by zebra mussel infestation was tested by suspending uncleaned and cleaned unionids in nearshore waters of western Lake Erie. Survival was determined, and newly settled zebra mussels were removed from clean unionids at eight intervals that ranged from 21 d to 77 d between 5 July 1990 and 3 July 1991. After 1 year, survival rates of uncleaned and cleaned unionids were 0% and 42%, respectively. Of the 10 species examined, only indivduals from 3 species (Amblema plicata plicata, Fusconaia flava, and Quadrula quadrula) survived 1 year. These species have relatively thick shells, which may have contributed to their survival. Removal of newly settled zebra mussels may be important to unionid survival because 98% of the zebra mussels removed after the initial cleaning were small mussels (<10 mm long) that could rapidly grow and cover unionids. At present, we do not know how zebra mussels cause mortality of unionids, but the removal of zebra mussels from unionids is the only method known that successfully reduces unionid mortality in waters colonized by zebra mussels.

  18. Chemical regulation of spawning in the zebra mussel (Dreissena polymorpha)

    USGS Publications Warehouse

    Ram, Jeffrey L.; Nichols, S. Jerrine; Nalepa, Thomas F.; Schloesser, Donald W.

    1992-01-01

    Previous literature suggests that spawning in bivalves is chemically regulated, both by environmental chemical cues and by internal chemical mediators. In a model proposed for zebra mussels, chemicals from phytoplankton initially trigger spawning, and chemicals associated with gametes provide further stimulus for spawning. The response to environmental chemicals is internally mediated by a pathway utilizing serotonin (5-hydroxytryptamine, a neurotransmitter), which acts directly on both male and female gonads. The role of serotonin and most other aspects of the model have been tested only on bivalves other than zebra mussels. The effect of serotonin on zebra mussel spawning was tested. Serotonin (10-5 and 10-3 M) injected into ripe males induced spawning, but injection of serotonin into females did not. Gametes were not released by 10-6 serotonin; in most cases, serotonin injection did not release gametes from immature recipients. Serotonin injection provides a reliable means for identifying ripe male zebra mussels and for obtaining zebra mussel sperm without the need for dissection.

  19. Prevention of zebra mussel infestation and dispersal during aquaculture operations

    USGS Publications Warehouse

    Waller, D.L.; Fisher, S.W.; Dabrowska, H.

    1996-01-01

    The zebra mussel Dreissena polymorpha, an exotic invasive species, poses a major threat to North American fish management programs and the aquaculture industry. Fish hatcheries may become infected with zebra mussels from a variety of sources, including the water supply, fish shipments, boats, and equipment. The hatcheries could then serve as agents for the overland dispersal of zebra mussels into stocked waters and to other fish hatcheries. We evaluated the effectiveness and safety of aquaculture chemicals for use in controlling zebra mussels in fish hatcheries and preventing dispersal of veligers during fish transport. Chemicals were evaluated for use in fish transport and as disinfectants for ponds and equipment. Standardized static toxicity tests were conducted with representative species of warmwater, coolwater, and coldwater fishes and with larval (3-d-old veligers), early juvenile (settling larvae), and adult zebra mussels. Chemical concentrations and exposure durations were based on recommended treatment levels for fish, eggs, and ponds. Recommended treatment levels were also exceeded, if necessary, to establish lethal levels for zebra mussels of different developmental stages. Our results indicate that some chemicals currently in use in hatcheries may be effective for controlling zebra mussels in various operations. Chloride salts were the safest and most effective therapeutants tested for use in fish transport. The toxicity of chloride salts to fish varied among species and with temperature; only one treatment regime (sodium chloride at 10,000 mg/L) was safe to all fish species that we tested, but it was only effective on veliger and settler stages of the zebra mussel. Effective disinfectants were benzalkonium chloride for use on equipment and rotenone for use in ponds after fish are harvested. The regulatory status of the identified chemicals is discussed as well as several nonchemical control alternatives.

  20. IMPACT OF WATER PH ON ZEBRA MUSSEL MORTALITY

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Daniel P. Molloy

    2002-10-15

    The experiments conducted this past quarter have suggested that the bacterium Pseudomonas fluorescens strain CL0145A is effective at killing zebra mussels throughout the entire range of pH values tested (7.2 to 8.6). Highest mortality was achieved at pH values characteristic of preferred zebra mussel waterbodies, i.e., hard waters with a range of 7.8 to 8.6. In all water types tested, however, ranging from very soft to very hard, considerable mussel kill was achieved (83 to 99% mean mortality), suggesting that regardless of the pH or hardness of the treated water, significant mussel kill can be achieved upon treatment with P.more » fluorescens strain CL0145A. These results further support the concept that this bacterium has significant potential for use as a zebra mussel control agent in power plant pipes receiving waters with a wide range of physical and chemical characteristics.« less

  1. Occurrence of zebra mussels in near-shore areas of western Lake Erie

    USGS Publications Warehouse

    Custer, Christine M.; Custer, T.W.

    1997-01-01

    Zebra mussels (Dreissena polymorpha) invaded the Great Lakes in the mid-1980s and quickly reached high densities. The objective of this study was to determine current consumption of zebra mussels by waterfowl in the Great Lakes region. Feeding Lesser Scaups (Aythya affinis), Greater Scaups (A. marila), Canvasbacks (A. valisineria), Redheads (A. americana), Buffleheads (Bucephala albeola) and Common Goldeneyes (B. clangula) were collected in western Lake Erie and in Lake St. Clair between fall and spring, 1992-1993 to determine food habits. All 10 Redheads, 97% of Lesser Scaups, 83% of Goldeneyes, 60% of Buffleheads and 9% of Canvasbacks contained one or more zebra mussels in their upper gastrointestinal tracts. The aggregate percent of zebra mussels in the diet of Lesser Scaups was higher in Lake Erie (98.6%) than in Lake St. Clair (54.4%). Zebra mussels, (aggregate percent) dominated the diet of Common Goldeneyes (79.2%) but not in Buffleheads (23.5%), Redheads (21%) or Canvasbacks (9%). Lesser Scaups from Lake Erie fed on larger zebra mussels ( = 10.7 i?? 0.66 mm SE) than did Lesser Scaups from Lake St. Clair ( = 4.4 i?? 0.22 mm). Lesser Scaups, Buffleheads and Common Goldeneyes from Lake Erie consumed zebra mussels of similar size.

  2. Preference of redear sunfish on zebra mussels and rams-horn snails

    USGS Publications Warehouse

    French, John R. P.; Morgan, Michael N.

    1995-01-01

    We tested prey preferences of adult (200- to 222-mm long) redear sunfish (Lepomis microlophus) on two size classes of zebra mussels (Dreissena polymorpha) and two-ridge rams-horns (Helisoma anceps) in experimental aquaria. We also tested physical limitations on consuming these mollusks and determined prey bioenergetic profitability. Redear sunfish strongly preferred rams-horns over zebra mussels, but they displayed no size preference for either prey. Ingestion was not physically limited since both prey species up to 15-mm long fit within the pharyngeal gapes of redear sunfish. Rams-horns were more bioenergetically profitable than zebra mussels and ingestion of rams-horn shell fragments was about three times less than zebra mussels. Rams-horns were somewhat more resistant to shell-crushing, but all size ranges of both prey species tested were crushable by redear sunfish. These studies suggested that the redear sunfish should not be considered a panacea for biological control of zebra mussels.

  3. Lesser scaup forage on zebra mussels at Cook nuclear plant, Michigan

    USGS Publications Warehouse

    Mitchell, C.A.; Carlson, J.

    1993-01-01

    Nineteen of 21 Lesser Scaup (Aythya affinis) entrained while foraging at the water intake structures of Cook Nuclear Plant, Bridgman, Michigan had consumed zebra mussels (Dreissena polymorpha). The average number of zebra mussels in the upper gastrointestinal tract was 260; maximum number was 987. Migrating Lesser Scaup found this new food source during the first winter following settlement of zebra mussels on the water intake structures of the power plant.

  4. A dominance shift from the zebra mussel to the invasive quagga mussel may alter the trophic transfer of metals.

    PubMed

    Matthews, Jonathan; Schipper, Aafke M; Hendriks, A Jan; Yen Le, T T; Bij de Vaate, Abraham; van der Velde, Gerard; Leuven, Rob S E W

    2015-08-01

    Bioinvasions are a major cause of biodiversity and ecosystem changes. The rapid range expansion of the invasive quagga mussel (Dreissena rostriformis bugensis) causing a dominance shift from zebra mussels (Dreissena polymorpha) to quagga mussels, may alter the risk of secondary poisoning to predators. Mussel samples were collected from various water bodies in the Netherlands, divided into size classes, and analysed for metal concentrations. Concentrations of nickel and copper in quagga mussels were significantly lower than in zebra mussels overall. In lakes, quagga mussels contained significantly higher concentrations of aluminium, iron and lead yet significantly lower concentrations of zinc66, cadmium111, copper, nickel, cobalt and molybdenum than zebra mussels. In the river water type quagga mussel soft tissues contained significantly lower concentrations of zinc66. Our results suggest that a dominance shift from zebra to quagga mussels may reduce metal exposure of predator species. Copyright © 2015 Elsevier Ltd. All rights reserved.

  5. The effect of zebra mussel consumption on growth of freshwater drum in Lake Erie

    USGS Publications Warehouse

    French, John R. P.; Bur, Michael T.

    1996-01-01

    We examined food habits and scale annuli of freshwater drum (Aplodinotus grunniens) from western Lake Erie to determine whether increasing predation on zebra mussels (Dreissena polymorpha) had affected growth of freshwater drum. The volume of zebra mussels in drum guts was greater in older fish. Growth of age classes 3–4, which consumed few zebra mussels, was greater in the most productive year for zebra mussels, July 1990–August 1991, than in three prior years. The total lengths of 5-year-old drum changed little. The mean total length of 6-year-old females has declined since the zebra mussel invaded Lake Erie, even through mussels comprised more than two-thirds of gut samples in these fish. These studies suggest that zebra mussels may not benefit freshwater drum when serving as a staple in the diet. PDF

  6. Predation of the zebra mussel (Dreissena polymorpha) by freshwater drum in western Lake Erie

    USGS Publications Warehouse

    French, John R. P.; Bur, Michael T.; Nalepa, Thomas F.; Schloesser, Donald W.

    1992-01-01

    Environmental and economic problems associated with the colonization of zebra mussels (Dreissena polymorpha) in western Lake Erie created a need to investigate control mechanisms. Predation by fishes is one potential means of control, but predation on zebra mussels by native fishes in Lake Erie is unknown. The freshwater drum (Aplodinotus grunniens) is the most likely fish predator since it is the only fish with pharyngeal teeth capable of crushing mollusk shells. In 1990, freshwater drum were collected in western Lake Erie from 9 sites near rocky reefs and 13 sites with silt or sand bottoms, and gut contents were examined. Predation on zebra mussels increased as drum size increased. Small drum (200-249 mm in length) fed mainly on dipterans, amphipods, and small fish; small zebra mussels (375 mm in length) fed almost exclusively on zebra mussels (seasons and locations combined). The smallest drum capable of crushing zebra mussel shells was 265 mm. Since freshwater drum over 375 mm feed heavily on zebra mussels, they may become a possible biological control mechanism for mussels in portions of North America.

  7. Invasion of the Zebra Mussels: A Mock Trial Activity

    ERIC Educational Resources Information Center

    Beck, Judy A.; Czerniak, Charlene M.

    2005-01-01

    In this activity, students learn about the important topic of invasive species, specifically Zebra Mussels. Students role-play different characters in a real-life situation: the trial of the Zebra Mussel for unlawful disruption of the Great Lakes ecosystem. Students will also learn about jurisprudential inquiry by examining the trial process. This…

  8. Predicting the spread of aquatic invaders: insight from 200 years of invasion by zebra mussels.

    PubMed

    Karatayev, Alexander Y; Burlakova, Lyubov E; Mastitsky, Sergey E; Padilla, Dianna K

    2015-03-01

    Understanding factors controlling the introduction and spread of species is crucial to improving the management of both natural populations and introduced species. The zebra mussel, Dreissena polymorpha, is considered the most aggressive freshwater invader in the Northern Hemisphere, and is a convenient model system for invasion biology, offering one of the best aquatic examples for examining the invasion process. We used data on 553 of the 1040 glacial lakes in the Republic of Belarus that were examined for the presence of zebra mussels. We used these data to build, test, and construct modified models to predict the spread of this invader, including selection of important parameters that could limit the spread of this invader. In spite of 200 years of continuous invasion, by 1996, zebra mussels were found in only 16.8% of all lakes studied. Of those lakes without zebra mussels in 1996, 66% were predicted to be susceptible to invasion by zebra mussels in the future, and 33% were predicted to be immune to successful invasion due to their water chemistry. Eighty lakes free of zebra mussels in 1996 were reexamined from 1997 to 2008. Of these, zebra mussels successfully invaded an additional 31 lakes, all of which were classified initially as suitable for zebra mussels; none of the lakes previously classified as unsuitable were invaded. We used the Random Forests classification algorithm with 16 environmental variables to determine the most important factors that differed between invaded lakes and those lakes suitable for invasion that have not yet been invaded. Distance to the nearest infested lakes was found to be the most important variable, followed by the lake area, color, average depth, and concentration of chloride, magnesium, and bicarbonate. This study provides a useful approach for predicting the spread of an invader across a landscape with variable habitat suitability that can be applied to a variety of species and systems.

  9. Spatio-temporal spawning and larval dynamics of a zebra mussel (Dreissena polymorpha) population in a North Texas Reservoir: implications for invasions in the southern United States

    USGS Publications Warehouse

    Churchill, Christopher John

    2013-01-01

    Zebra mussels were first observed in Texas in 2009 in a reservoir (Lake Texoma) on the Texas-Oklahoma border. In 2012, an established population was found in a near-by reservoir, Ray Roberts Lake, and in June 2013, settled mussels were detected in a third north Texas reservoir, Lake Lewisville. An established population was detected in Belton Lake in September 2013. With the exception of Louisiana, these occurrences in Texas mark the current southern extent of the range of this species in the United States. Previous studies indicate that zebra mussel populations could be affected by environmental conditions, especially increased temperatures and extreme droughts, which are characteristic of surface waters of the southern and southwestern United States. Data collected during the first three years (2010–12) of a long-term monitoring program were analyzed to determine if spatio-temporal zebra mussel spawning and larval dynamics were related to physicochemical water properties in Lake Texoma. Reproductive output of the local population was significantly related to water temperature and lake elevation. Estimated mean date of first spawn in Lake Texoma was approximately 1.5 months earlier and peak veliger densities were observed two months earlier than in Lake Erie. Annual maximum veliger density declined significantly during the study period (p < 0.0001). A population crash occurred as a result of thermal stress and variability of lake elevation. In summer 2011, water temperatures peaked at 34.3°C and lake elevation declined to the lowest level recorded during the previous 18 years, which resulted in desiccation of substantial numbers of settled mussels in littoral zones. Veliger spatial distributions were associated with physicochemical stratification characteristics. Veligers were observed in the deepest oxygenated water after lake stratification, which occurred in late spring. Results of this study indicate environmental conditions can influence variability of

  10. Effects of shell morphology on mechanics of zebra and quagga mussel locomotion

    Treesearch

    S. M. Peyer; J. C. Hermanson; C. E. Lee

    2011-01-01

    Although zebra mussels (Dreissena polymorpha) initially colonized shallow habitats within the North American Great Lakes, quagga mussels (Dreissena bugensis) are becoming dominant in both shallow- and deep-water habitats. Shell morphology differs among zebra, shallow quagga and deep quagga mussels but functional consequences of...

  11. Do zebra mussels (Dreissena polymorpha) alter lake water chemistry in a way that favours Microcystis growth?

    PubMed

    Bykova, Olga; Laursen, Andrew; Bostan, Vadim; Bautista, Joseph; McCarthy, Lynda

    2006-12-01

    This study examined possible relationships between the presence of zebra mussels (Dreissena polymorpha) and Microcystis spp. abundance. Experiments were conducted in 12 microcosms designed to mimic shallow lake ecosystems. Fresh, aerated water with phytoplankton (pseudokirchneriella spp. and Microcystis spp.) was pumped into each microcosm daily to ensure zebra mussels were exposed to oxygen and food. Microcosms containing zebra mussels experienced significantly higher fluxes of nitrate (p=0.019) and lower fluxes of ortho-phosphate (p=0.047) into sediments. In a second experiment, water column nutrient concentrations were compared in microcosms with and without live zebra mussels. Consistent with results of the previous experiment, microcosms with zebra mussels had significantly less nitrate (p=0.023) and organic nitrogen (p=0.003) in the water column, while ammonium (p=0.074), phosphate (p=0.491), and dissolved organic carbon (p=0.820) in the water column were not different between microcosms with or without zebra mussels. Microcosms with zebra mussels also experienced a reduction in green algae (pseudokirchneriella) (p<0.001) and an increase in abundance of Microcystis (p<0.001) relative to microcosms without zebra mussels. In an experiment without zebra mussels, nutrient ratios (N/P) were manipulated to determine potential links between N/P and relative abundance of each phytoplankton. Manipulation of N/P was intended to mimic differences observed in microcosms with and without zebra mussels in the previous experiment. Low N/P (mimicking microcosms with zebra mussels) was related to an increase in Microcystis (p<0.001) and Microcystis/Pseudokirchneriella biovolume (p<0.001). It is this shift in N/P, and possibly some level of selective feeding, that is believed to have driven changes in the relative abundance of Microcystis. In lakes invaded by zebra mussels, alterations in the processing of nitrogen and phosphorus could contribute to the re-emergence of

  12. Bioaccumulation of pathogenic bacteria and amoeba by zebra mussels and their presence in watercourses.

    PubMed

    Mosteo, R; Goñi, P; Miguel, N; Abadías, J; Valero, P; Ormad, M P

    2016-01-01

    Dreissena polymorpha (the zebra mussel) has been invading freshwater bodies in Europe since the beginning of the nineteenth century. Filter-feeding organisms can accumulate and concentrate both chemical and biological contaminants in their tissues. Therefore, zebra mussels are recognized as indicators of freshwater quality. In this work, the capacity of the zebra mussel to accumulate human pathogenic bacteria and protozoa has been evaluated and the sanitary risk associated with their presence in surface water has also been assessed. The results show a good correlation between the pathogenic bacteria concentration in zebra mussels and in watercourses. Zebra mussels could therefore be used as an indicator of biological contamination. The bacteria (Escherichia coli, Enterococcus spp., Pseudomonas spp., and Salmonella spp.) and parasites (Cryptosporidium oocysts and free-living amoebae) detected in these mussels reflect a potential sanitary risk in water.

  13. Heterozygosity and fitness: No strong association in Great Lakes populations of the zebra mussel, Dreissena Polymorpha (Pallas)

    USGS Publications Warehouse

    Lewis, K.M.; Feder, J.L.; Horvath, T.G.; Lamberti, G.A.

    2000-01-01

    A number of studies have found positive associations between allozyme heterozygosity and fitness surrogates (e.g., body size and growth rate) for marine molluscs. We investigated whether similar relationships exist for freshwater populations of the zebra mussel, Dreissena polymorpha. Only one significant correlation between multi-locus heterozygosity and shell length was observed for a total of 22 D. polymorpha populations surveyed from midwestern U.S.A. lakes and streams, and the result was not significant on a table-wide basis. Meta-analysis revealed a significant common correlation coefficient (effect magnitude) between multi-locus heterozygosity and shell length across all 22 sites (rc = 0.052, P = 0.019, 1557 df). However, the variance in shell length explained by multi-locus heterozygosity was small (rc2 = 0.0027), implying a weak causal relationship if any. Also, we saw no relationship between heterozygosity and growth rate in a one-year field enclosure experiment. A significant heterozygosity-shell length correlation previously reported for a zebra mussel population at Put-in-Bay, Lake Erie, Ohio, may have been the product of unique population dynamics, rather than natural selection. Similar demographic considerations may contribute to inconsistencies in heterozygosity-fitness correlations seen for other molluscs.

  14. Control Strategies for Zebra Mussel Infestations at Public Facilities

    DTIC Science & Technology

    1992-07-01

    detailed examina- tion of hard -to-reach surfaces or specific components (such as fire protection systems or intake pipes for sensor devices) should...trash racks. Trash racks could become partially clogged with zebra mussels, shells , and other debris. Flow through the openings would be reduced, and... shells to the top of the lock wall. These are now used by Ontario Hydro for removing zebra mussels. At most facilities, the culvert is totally dewatered

  15. Great Lakes clams find refuge from zebra mussels in restored, lake-connected marsh (Ohio)

    USGS Publications Warehouse

    Nichols, S. Jerrine; Wilcox, Douglas A.

    2004-01-01

    Since the early 1990s, more than 95 percent of the freshwater clams once found in Lake Erie have died due to the exotic zebara mussel (Dreissena polymorpha). Zebra mussels attach themselves to native clams in large numbers, impeding the ability of the clams to eat and burrow. However, in 1996, we discovered a population of native clams in Metzger Marsh in western Lake Erie (about 50 miles [80 km] east of Toledo) that were thriving despite the longtime presence of zebra mussel in surrounding waters. At that time, Metzger Marsh was undergoing extensive restoration, including construction of a dike to replace the eroded barrier beach and of a water-control structure to maintain hydrologic connections with the lake (Wilcox and Whillans 1999). The restoration plan called for a drawdown of water levels to promote plant growth from the seedbank -- a process that would also destroy most of the clam population. State and federal resource managers recommended removing as many clams as possible to a site that was isolated from zebra mussels, and then returning them to the marsh after it was restored. We removed about 7,000 native clams in 1996 and moved them back to Metzger Marsh in 1999.

  16. Will the Displacement of Zebra Mussels by Quagga Mussels Increase Water Clarity in Shallow Lakes during Summer? Results from a Mesocosm Experiment.

    PubMed

    Mei, Xueying; Zhang, Xiufeng; Kassam, Sinan-Saleh; Rudstam, Lars G

    2016-01-01

    Zebra mussels (Dreissena polymorpha) are known to increase water clarity and affect ecosystem processes in invaded lakes. During the last decade, the conspecific quagga mussels (D. rostriformis bugensis) have displaced zebra mussels in many ecosystems including shallow lakes such as Oneida Lake, New York. In this study, an eight-week mesocosm experiment was conducted to test the hypothesis that the displacement of zebra mussels by quagga mussels leads to further decreases in phytoplankton and increases in water clarity resulting in increases in benthic algae. We found that the presence of zebra mussels alone (ZM), quagga mussels alone (QM), or an equal number of both species (ZQ) reduced total phosphorus (TP) and phytoplankton Chl a. Total suspended solids (TSS) was reduced in ZM and ZQ treatments. Light intensity at the sediment surface was higher in all three mussel treatments than in the no-mussel controls but there was no difference among the mussel treatments. There was no increase in benthic algae biomass in the mussel treatments compared with the no-mussel controls. Importantly, there was no significant difference in nutrient (TP, soluble reactive phosphorus and NO3-) levels, TSS, phytoplankton Chl a, benthic algal Chl a, or light intensity on the sediment surface between ZM, QM and ZQ treatments. These results confirm the strong effect of both mussel species on water clarity and indicate that the displacement of zebra mussel by an equivalent biomass of quagga mussel is not likely to lead to further increases in water clarity, at least for the limnological conditions, including summer temperature, tested in this experiment.

  17. Will the Displacement of Zebra Mussels by Quagga Mussels Increase Water Clarity in Shallow Lakes during Summer? Results from a Mesocosm Experiment

    PubMed Central

    Kassam, Sinan-Saleh; Rudstam, Lars G.

    2016-01-01

    Zebra mussels (Dreissena polymorpha) are known to increase water clarity and affect ecosystem processes in invaded lakes. During the last decade, the conspecific quagga mussels (D. rostriformis bugensis) have displaced zebra mussels in many ecosystems including shallow lakes such as Oneida Lake, New York. In this study, an eight-week mesocosm experiment was conducted to test the hypothesis that the displacement of zebra mussels by quagga mussels leads to further decreases in phytoplankton and increases in water clarity resulting in increases in benthic algae. We found that the presence of zebra mussels alone (ZM), quagga mussels alone (QM), or an equal number of both species (ZQ) reduced total phosphorus (TP) and phytoplankton Chl a. Total suspended solids (TSS) was reduced in ZM and ZQ treatments. Light intensity at the sediment surface was higher in all three mussel treatments than in the no-mussel controls but there was no difference among the mussel treatments. There was no increase in benthic algae biomass in the mussel treatments compared with the no-mussel controls. Importantly, there was no significant difference in nutrient (TP, soluble reactive phosphorus and NO3-) levels, TSS, phytoplankton Chl a, benthic algal Chl a, or light intensity on the sediment surface between ZM, QM and ZQ treatments. These results confirm the strong effect of both mussel species on water clarity and indicate that the displacement of zebra mussel by an equivalent biomass of quagga mussel is not likely to lead to further increases in water clarity, at least for the limnological conditions, including summer temperature, tested in this experiment. PMID:28005940

  18. Effects of temperature and aerial exposure on the BOD of waste zebra mussels removed from navigational locks.

    PubMed

    Aldridge, D W; Payne, B S

    2001-08-01

    This laboratory study evaluated the effects of temperature and aerial exposure on BOD5 (5-day BOD) of waste zebra mussels of the type generated by maintenance operations on dams and navigational locks. The term waste zebra mussels includes the mussels and their associated debris with the latter including sediment, feces, pseudofeces and other small aquatic organisms. The BOD5 of waste zebra mussel was evaluated after aerial exposure of 3 and 10 days at temperatures of 5, 10, and 20 degrees C. The mean BOD5 values for waste zebra mussels in this study ranged from 18,500 to 30,600 mg O2/l. Factorial ANOVA analysis revealed that both temperature and aerial exposure had a negative effect on waste zebra mussel BOD5 (P<0.05) but there was no significant interaction effect (P = 0.119). Multiple regression analysis predicted that for the range of treatment conditions used in this study each 1 degrees C increase in temperature reduced the waste zebra mussel BOD5 by 284mg O2/l or 0.93% of the maximum mean BOD5. Each I day increase in aerial exposure reduced waste zebra mussel BOD5 by 987 mg O2/l or 3.22% of the maximum mean BOD5. Aerial exposure of waste zebra mussels substantially reduces waste BOD5.

  19. Factorial microarray analysis of zebra mussel (Dreissena polymorpha: Dreissenidae, Bivalvia) adhesion

    PubMed Central

    2010-01-01

    Background The zebra mussel (Dreissena polymorpha) has been well known for its expertise in attaching to substances under the water. Studies in past decades on this underwater adhesion focused on the adhesive protein isolated from the byssogenesis apparatus of the zebra mussel. However, the mechanism of the initiation, maintenance, and determination of the attachment process remains largely unknown. Results In this study, we used a zebra mussel cDNA microarray previously developed in our lab and a factorial analysis to identify the genes that were involved in response to the changes of four factors: temperature (Factor A), current velocity (Factor B), dissolved oxygen (Factor C), and byssogenesis status (Factor D). Twenty probes in the microarray were found to be modified by one of the factors. The transcription products of four selected genes, DPFP-BG20_A01, EGP-BG97/192_B06, EGP-BG13_G05, and NH-BG17_C09 were unique to the zebra mussel foot based on the results of quantitative reverse transcription PCR (qRT-PCR). The expression profiles of these four genes under the attachment and non-attachment were also confirmed by qRT-PCR and the result is accordant to that from microarray assay. The in situ hybridization with the RNA probes of two identified genes DPFP-BG20_A01 and EGP-BG97/192_B06 indicated that both of them were expressed by a type of exocrine gland cell located in the middle part of the zebra mussel foot. Conclusions The results of this study suggested that the changes of D. polymorpha byssogenesis status and the environmental factors can dramatically affect the expression profiles of the genes unique to the foot. It turns out that the factorial design and analysis of the microarray experiment is a reliable method to identify the influence of multiple factors on the expression profiles of the probesets in the microarray; therein it provides a powerful tool to reveal the mechanism of zebra mussel underwater attachment. PMID:20509938

  20. Population dynamics of zebra mussels Dreissena polymorpha (Pallas, 1771) during the initial invasion of the Upper Mississippi River, USA

    USGS Publications Warehouse

    Cope, W.G.; Bartsch, M.R.; Hightower, J.E.

    2006-01-01

    The aim of this study was to document and model the population dynamics of zebra mussels Dreissena polymorpha (Pallas, 1771) in Pool 8 of the Upper Mississippi River (UMR), USA, for five consecutive years (1992-1996) following their initial discovery in September 1991. Artificial substrates (concrete blocks, 0.49 m2 surface area) were deployed on or around the first of May at two sites within each of two habitat types (main channel border and contiguous backwater). Blocks were removed monthly (30 ?? 10 d) from the end of May to the end of October to obtain density and growth information. Some blocks deployed in May 1995 were retrieved in April 1996 to obtain information about overwinter growth and survival. The annual density of zebra mussels in Pool 8 of the UMR increased from 3.5/m2 in 1992 to 14,956/m 2 in 1996. The average May-October growth rate of newly recruited individuals, based on a von Bertalanffy growth model fitted to monthly shell-length composition data, was 0.11 mm/d. Model estimates of the average survival rate varied from 21 to 100% per month. Estimated recruitment varied substantially among months, with highest levels occurring in September-October of 1994 and 1996, and in July of 1995. Recruitment and density in both habitat types increased by two orders of magnitude in 1996. Follow-up studies will be necessary to assess the long-term stability of zebra mussel populations in the UMR; this study provides the critical baseline information needed for those future comparisons. ?? Published by Oxford University Press on behalf of The Malacological Society of London 2006.

  1. Seasonal effects of the zebra mussel (Dreissena polymorpha) on sediment denitrification rates in Pool 8 of the Upper Mississippi River

    USGS Publications Warehouse

    Bruesewitz, Denise A.; Tank, Jennifer L.; Bernot, Melody J.; Richardson, William B.; Strauss, Eric A.

    2006-01-01

    Zebra mussels (Dreissena polymorpha) have altered the structure of invaded ecosystems and exhibit characteristics that suggest they may influence ecosystem processes such as nitrogen (N) cycling. We measured denitrification rates seasonally on sediments underlying zebra mussel beds collected from the impounded zone of Navigation Pool 8 of the Upper Mississippi River. Denitrification assays were amended with nutrients to characterize variation in nutrient limitation of denitrification in the presence or absence of zebra mussels. Denitrification rates at zebra mussel sites were high relative to sites without zebra mussels in February 2004 (repeated measures analysis of variance (RM ANOVA), p = 0.005), potentially because of high NO3-N variability from nitrification of high NH4+ zebra mussel waste. Denitrification rates were highest in June 2003 (RM ANOVA, p 3-N concentrations during the study (linear regression, R2 = 0.72, p p ≤ 0.01). Examining how zebra mussels influence denitrification rates will aid in developing a more complete understanding of the impact of zebra mussels and more effective management strategies of eutrophic waters.

  2. Longitudinal patterns in abundance of the zebra mussel (Dreissena polymorpha) in the upper Mississippi River

    USGS Publications Warehouse

    Cope, W.G.; Bartsch, M.R.; Hayden, R.R.

    1997-01-01

    We assessed the abundance of zebra mussels in the upper Mississippi River during 1995, four years after they were first found in the river. Samplers were deployed from May 30 to October 19, 1995, at 19 lock and dam facilities in the upper Mississippi River from Minneapolis, Minnesota, to Muscatine, Iowa. Zebra mussels were found at every lock and dam except the two sites farthest upstream (Minneapolis). Generally, densities of zebra mussels were greatest at sites 161 km and farther downstream of the Minneapolis area. The greatest mean mussel density was 11,432/m(2) at Fulton, Illinois.

  3. Environmentally Safe Control of Zebra Mussel Fouling

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Daniel Molloy

    2008-02-29

    The two primary objectives of this USDOE-NETL contract were successfully achieved during the project: (1) to accelerate research on the development of the bacterium Pseudomonas fluorescens strain CL145A (Pf-CL145A) as a biocontrol agent for zebra mussels (Dreissena polymorpha) and quagga mussels (Dreissena rostriformis bugensis)--two invasive freshwater bivalve species that are infesting water pipes in power plants; and (2) to identify a private-sector company that would move forward to commercialize Pf-CL145A as a substitute for the current polluting use of biocide chemicals for control of these dreissenid mussels in power plant pipes.

  4. Zebra Mussel Antifouling Activity of the Marine Natural Product Aaptamine and Analogs

    PubMed Central

    Diers, Jeffrey A.; Bowling, John J.; Duke, Stephen O.; Wahyuono, Subagus; Kelly, Michelle; Hamann, Mark T.

    2016-01-01

    Several aaptamine derivatives were selected as potential zebra mussel (Dreissena polymorpha) antifoulants because of the noteworthy absence of fouling observed on Aaptos sponges. Sponges of the genus Aaptos collected in Manado, Indonesia consistently produce aaptamine-type alkaloids. To date, aaptamine and its derivatives have not been carefully evaluated for their antifoulant properties. Structure–activity relationship studies were conducted using several aaptamine derivatives in a zebra mussel antifouling assay. From these data, three analogs have shown significant antifouling activity against zebra mussel attachment. Aaptamine, isoaaptamine, and the demethylated aaptamine compounds used in the zebra mussel assay produced EC50 values of 24.2, 11.6, and 18.6 μM, respectively. In addition, neither aaptamine nor isoaaptamine produced a phytotoxic response (as high as 300 μM) toward a nontarget organism, Lemna pausicostata, in a 7-day exposure. The use of these aaptamine derivatives from Aaptos sp. as potential environmentally benign antifouling alternatives to metal-based paints and preservatives is significant, not only as a possible control of fouling organisms, but also to highlight the ecological importance of these and similar biochemical defenses. PMID:16718618

  5. Efficacy of Pseudomonas fluorescens (Pf-CL145A) spray dried powder for controlling zebra mussels adhering to test substrates

    USGS Publications Warehouse

    Luoma, James A.; Severson, Todd J.; Weber, Kerry L.; Mayer, Denise A.

    2015-01-01

    Approximately 30 days after exposure, zebra mussels were sorted into live and dead, and enumerated. Mean survival of zebra mussels in control treatments exceeded 95 percent. Mean survival of zebra mussels in the Lake Carlos WWC SDP-treated groups ranged from 0.5 to 2.1 percent and when compared at the same exposure duration, no difference was detected in survival between the 50 and 100 milligrams per liter (mg/L) treatment groups. Similarly, mean survival of zebra mussels in the Shawano Lake WWC SDP-treated groups ranged from 2.0 to 12.6 percent and when compared at the same exposure duration, no difference was detected in survival between the 50- and 100-mg/L treatment groups. Mean survival of zebra mussels in the Lake Carlos BI trial SDP-treated groups did not differ (p = 0.93) and was 18.1 and 18.0 percent in the 50- and 100-mg/L treatment groups, respectively. Mean survival of zebra mussels in the Shawano Lake BI trial SDP-treated groups differed (p < 0.01) and was 2.9 and 0.9 percent in the 50- and 100-mg/L treatment groups, respectively. Survival of zebra mussels assigned to the SDP-treated groups in the Lake Carlos WWC trial (12-hour exposure duration) differed from the survival of zebra mussels assigned to the SDP-treated groups in the Lake Carlos BI trial; however, after modification of the BI application technique, no difference (p = 0.22) was detected between the survival of zebra mussel in the Shawano Lake WWC (12-hour exposure duration) and BI trials.

  6. Identification of larvae: The zebra mussel (Dreissena polymorpha), quagga mussel (Dreissena rosteriformis bugensis), and Asian clam (Corbicula fluminea)

    USGS Publications Warehouse

    Nichols, S. Jerrine; Black, M.G.

    1994-01-01

    There are presently four freshwater bivalves in the United States that produce larvae or veligers commonly found in the water column: two forms of Asian clams and two species of dreissenids. Portions of the geographic range of three of these bivalves, one species of Asian clam (Corbicula fluminea), zebra mussels (Dreissena polymorpha), and quagga mussels (Dreissena rosteriformis bugensis), overlap, causing problems with larval identification. To determine which characteristics can be used to separate larval forms, adult Asian clams, quaggas, and zebra mussels were brought into the laboratory and induced to spawn, and the resulting larvae were reared. Hybrids between quaggas and zebra mussels were also produced, but not reared to maturity. Characteristics allowing for the most rapid and accurate separation of larvae were hinge length, shell length/height, shell shape, shell size, and the presence or absence of a foot and velum. These characteristics were observed in laboratory-reared larvae of known parentage and field-caught larvae of unknown parentage. In most cases, larvae of the Asian clam can be readily separated from those produced by either type of dreissenid on the basis of shell size and presence of a foot. Separating the gametes and embryos of the two types of dreissenids is not possible, but after shell formation, most of the larval stages can be distinguished. Hinge length, shell length/height, and the similarity in size of the shell valves can be used to separate straight-hinged, umbonal, pediveliger, and plantigrade larvae. Quagga × zebra mussel hybrids show characteristics of both parents and are difficult to identify.

  7. Factors Affecting Zebra Mussel Kill by the Bacterium Pseudomonas fluorescens

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Daniel P. Molloy

    2004-02-24

    The specific purpose of this research project was to identify factors that affect zebra mussel kill by the bacterium Pseudomonas fluorescens. Test results obtained during this three-year project identified the following key variables as affecting mussel kill: treatment concentration, treatment duration, mussel siphoning activity, dissolved oxygen concentration, water temperature, and naturally suspended particle load. Using this latter information, the project culminated in a series of pipe tests which achieved high mussel kill inside power plants under once-through conditions using service water in artificial pipes.

  8. An assessment of total and leachable contaminants in zebra mussels (Dreissena polymorpha) from Lake Erie

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Doherty, F.G.; Evans, D.W.; Neuhauser, E.F.

    Samples of zebra mussels, Dreissena polymorpha, from populations infesting two power generating stations on Lake Erie were subjected to tests assessing the potential for leaching of metals and other (inorganic and organic) contaminants from mussel waste destined for disposal in conventional landfills. These tests revealed that mussels collected from Ontario Hydro's Nanticoke Thermal Generating Station and Niagara Mohawk Power Corporation's Dunkirk Steam Station did not release hazardous materials in excess of limits set forth in Canadian and U.S. regulations, respectively. A variety of metals and inorganic materials leached from Nanticoke mussels at levels significantly lower than the registration limits formore » those analytes. Detectable levels of chloroform (0.080 mg/liter) and barium (3.3 mg/liter) leached from Dunkirk mussels at > 30-fold lower levels than U.S. regulatory action limits for those materials. Whole body analyses revealed a lack of detectable levels of herbicides and pesticides in either population with a variety of metals and inorganic constituents in all samples from both populations. The physiological condition of Dunkirk mussels appeared to be consistent with that of other Lake Erie populations based on percentage water and total fat content of soft tissues.« less

  9. An assessment of total and leachable contaminants in zebra mussels (Dreissena polymorpha) from Lake Erie.

    PubMed

    Doherty, F G; Evans, D W; Neuhauser, E F

    1993-06-01

    Samples of zebra mussels, Dreissena polymorpha, from populations infesting two power generating stations on Lake Erie were subjected to tests assessing the potential for leaching of metals and other (inorganic and organic) contaminants from mussel waste destined for disposal in conventional landfills. These tests revealed that mussels collected from Ontario Hydro's Nanticoke Thermal Generating Station and Niagara Mohawk Power Corporation's Dunkirk Steam Station did not release hazardous materials in excess of limits set forth in Canadian and U.S. regulations, respectively. A variety of metals and inorganic materials leached from Nanticoke mussels at levels significantly lower than the registration limits for those analytes. Detectable levels of chloroform (0.080 mg/liter) and barium (3.3 mg/liter) leached from Dunkirk mussels at > 30-fold lower levels than U.S. regulatory action limits for those materials. Whole body analyses revealed a lack of detectable levels of herbicides and pesticides in either population with a variety of metals and inorganic constituents in all samples from both populations. The physiological condition of Dunkirk mussels appeared to be consistent with that of other Lake Erie populations based on percentage water and total fat content of soft tissues.

  10. Zebra mussels (Dreissena polymorpha) limit food for larval fish (Pimephales promelas) in turbulent systems: A bioenergetics analysis

    USGS Publications Warehouse

    Bartsch, L.A.; Richardson, W.B.; Sandheinrich, M.B.

    2003-01-01

    We conducted a factorial experiment, in outdoor mesocosms, on the effects of zebra mussels and water column mixing (i.e., turbulence) on the diet, growth, and survival of larval fathead minnows (Pimephales promelas). Significant (P < 0.05) larval mortality occurred by the end of the experiment with the highest mortality (90%) occurring in the presence of both turbulence and zebra mussels, whereas mortality was 37% in treatment with turbulence and 17% and 18% in the zebra mussels treatment, and the control, respectively. The size of individual fish was significantly different among treatments at the end of the experiment and was inversely related to survival. Levels of trophic resources (i.e., phyto and zooplankton) varied among treatments and were treatment specific. Turbulent mixing facilitated removal of phytoplankton by zebra mussels by making the entire water column of the tanks available to these benthic filter feeders. Early in the experiment (Day = 0 to 14) the physical process of turbulent mixing likely caused a reduction in standing stocks of zooplankton. The interactive effect of turbulence and mussels reduced copepod and rotifer stocks, through physical processes and through filtration by zebra mussels, relative to the turbulence treatment. The reductions in the number of total zooplankton in the turbulent mixing mesocosms and the further reduction of rotifer and copepod in the turbulence and mussels treatment coincided with a period of increased reliance of larval fathead minnows on these prey. Estimates of consumption from bioenergetics modeling and measured prey standing stocks indicated caloric resources of suitable prey in turbulence treatments during the early weeks of the experiment were insufficient to prevent starvation. Early mortality in the turbulence and mussels treatment likely released surviving fish from intense intraspecific competition and resulted in higher individual growth rates. A combination of high abundance of zebra mussels in an

  11. Zebra mussels (Dreissena polymorpha) limit food for larval fish (Pimephales promelas) in turbulent systems: a bioenergetics analysis

    USGS Publications Warehouse

    Bartsch, L.A.; Richardson, W.B.; Sandheinrich, M.B.

    2003-01-01

    We conducted a factorial experiment, in outdoor mesocosms, on the effects of zebra mussels and water column mixing (i.e., turbulence) on the diet, growth, and survival of larval fathead minnows (Pimephales promelas). Significant (P < 0.05) larval mortality occurred by the end of the experiment with the highest mortality (90%) occurring in the presence of both turbulence and zebra mussels, whereas mortality was 37% in treatment with turbulence and 17% and 18% in the zebra mussels treatment, and the control, respectively. The size of individual fish was significantly different among treatments at the end of the experiment and was inversely related to survival. Levels of trophic resources (i.e., phyto and zooplankton) varied among treatments and were treatment specific. Turbulent mixing facilitated removal of phytoplankton by zebra mussels by making the entire water column of the tanks available to these benthic filter feeders. Early in the experiment (Day = 0 to 14) the physical process of turbulent mixing likely caused a reduction in standing stocks of zooplankton. The interactive effect of turbulence and mussels reduced copepod and rotifer stocks, through physical processes and through filtration by zebra mussels, relative to the turbulence treatment. The reductions in the number of total zooplankton in the turbulent mixing mesocosms and the further reduction of rotifer and copepod in the turbulence and mussels treatment coincided with a period of increased reliance of larval fathead minnows on these prey. Estimates of consumption from bioenergetics modeling and measured prey standing stocks indicated caloric resources of suitable prey in turbulence treatments during the early weeks of the experiment were insufficient to prevent starvation. Early mortality in the turbulence and mussels treatment likely released surviving fish from intense intraspecific competition and resulted in higher individual growth rates. A combination of high abundance of zebra mussels in an

  12. Copper in indigenous and transplanted zebra mussels in relation to changing water concentrations and body weight

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Mersch, J.; Wagner, P.; Pihan, J.C.

    Zebra mussels, Dreissena polymorpha, were collected monthly from a copper-contaminated reservoir over a period of nearly 3 years. Copper concentrations in the organisms showed marked fluctuations reflecting changes in the water contamination. Bioconcentration patterns were influenced by the specific capacity of this sentinel organism to biologically integrate the continuously evolving water pollution; the sampling pattern, which inevitably introduced a certain subjectivity into monitoring results; and weight changes in the animals within the yearly cycle. Consequently, the successive monthly indications obtained with the zebra mussels provided a current biological assessment of a complex dynamic contamination situation. In a second experiment, cagedmore » mussels from three different populations were transferred for 3 months into the reservoir and sampled on six occasions. Mortality rates, attachment capacity, and a condition index revealed no substantial fitness disturbances in the transplanted organisms. Differences in dry weight throughout the experiment were attributable to the initial characteristics of each population. The influence of body mass on monitoring results was eliminated by replacing copper concentrations ({micro}g/g dry weight) with copper burdens ({micro}g/specimen). In terms of copper burdens, the three transplanted populations exhibited very similar metal patterns. Moderate quantitative differences between introduced and indigenous populations were interpreted as the result of physiological adaptation of the indigenous mussels to their contaminated environment. This study showed that the transfer technique with D. polymorpha is a useful tool for active biomonitoring programs.« less

  13. The Importance of Non-Native Prey, the Zebra Mussel Dreissena polymorpha, for the Declining Greater Scaup Aythya marila: A Case Study at a Key European Staging and Wintering Site.

    PubMed

    Marchowski, Dominik; Neubauer, Grzegorz; Ławicki, Łukasz; Woźniczka, Adam; Wysocki, Dariusz; Guentzel, Sebastian; Jarzemski, Maciej

    2015-01-01

    The European population of Greater Scaup Aythya marila has experienced an alarming, ~60% decline in numbers over the last two decades. The brackish lagoons of the Odra River Estuary (ORE) in the south-western Baltic Sea, represent an important area for the species during the non-breeding season in Europe. The lagoons regularly support over 20 000 Scaup, with peaks exceeding 100 000 (38%-70% of the population wintering in NW Europe and the highest number recorded in April 2011-105 700). In the ORE, Scaup feed almost exclusively on the non-native Zebra Mussel Dreissena polymorpha. This mussel was present in the ORE already in the 19th century and continues to be superabundant. Using the results of 22 Scaup censuses (November to April 2002/2003 to 2013/2014) from the whole ORE (523 km2 of water), we show that Scaup flocks follow areas with the greatest area of occurrence and biomass of the Zebra Mussel, while areas with low mussel densities are ignored. The numbers of Scaup in the ORE are primarily related to the area of Zebra Mussel occurrence on the lagoon's bottom (km2) in a non-linear fashion. Zebra Mussels were absolutely prevalent (97% of biomass) in the digestive tracts of birds unintentionally by-caught in fishing nets (n = 32). We estimate that Scaup alone consume an average of 5 400 tons of Zebra Mussels annually, which represents 5.6% of the total resources of the mussel in the ORE. Our results provide a clear picture of the strong dependence of the declining, migratory duck species on the non-native mussel, its primary food in the ORE. Our findings are particularly important as they can form the basis for the conservation action plan aimed at saving the north-western European populations of Scaup.

  14. The Importance of Non-Native Prey, the Zebra Mussel Dreissena polymorpha, for the Declining Greater Scaup Aythya marila: A Case Study at a Key European Staging and Wintering Site

    PubMed Central

    Marchowski, Dominik; Neubauer, Grzegorz; Ławicki, Łukasz; Woźniczka, Adam; Wysocki, Dariusz; Guentzel, Sebastian; Jarzemski, Maciej

    2015-01-01

    The European population of Greater Scaup Aythya marila has experienced an alarming, ~60% decline in numbers over the last two decades. The brackish lagoons of the Odra River Estuary (ORE) in the south-western Baltic Sea, represent an important area for the species during the non-breeding season in Europe. The lagoons regularly support over 20 000 Scaup, with peaks exceeding 100 000 (38%–70% of the population wintering in NW Europe and the highest number recorded in April 2011–105 700). In the ORE, Scaup feed almost exclusively on the non-native Zebra Mussel Dreissena polymorpha. This mussel was present in the ORE already in the 19th century and continues to be superabundant. Using the results of 22 Scaup censuses (November to April 2002/2003 to 2013/2014) from the whole ORE (523 km2 of water), we show that Scaup flocks follow areas with the greatest area of occurrence and biomass of the Zebra Mussel, while areas with low mussel densities are ignored. The numbers of Scaup in the ORE are primarily related to the area of Zebra Mussel occurrence on the lagoon’s bottom (km2) in a non-linear fashion. Zebra Mussels were absolutely prevalent (97% of biomass) in the digestive tracts of birds unintentionally by-caught in fishing nets (n = 32). We estimate that Scaup alone consume an average of 5 400 tons of Zebra Mussels annually, which represents 5.6% of the total resources of the mussel in the ORE. Our results provide a clear picture of the strong dependence of the declining, migratory duck species on the non-native mussel, its primary food in the ORE. Our findings are particularly important as they can form the basis for the conservation action plan aimed at saving the north-western European populations of Scaup. PMID:26709707

  15. Assessing the potential for fish predation to impact zebra mussels (Dreissena polymorpha): Insight from bioenergetics models

    USGS Publications Warehouse

    Eggleton, M.A.; Miranda, L.E.; Kirk, J.P.

    2004-01-01

    Rates of annual food consumption and biomass were modeled for several fish species across representative rivers and lakes in eastern North America. Results were combined to assess the relative potential of fish predation to impact zebra mussels (Dreissena polymorpha). Predicted annual food consumption by fishes in southern waters was over 100% greater than that in northern systems because of warmer annual water temperatures and presumed increases in metabolic demand. Although generally increasing with latitude, biomasses of several key zebra mussel fish predators did not change significantly across latitudes. Biomasses of some less abundant fish predators did increase significantly with latitude, but increases were not of the magnitude to offset predicted decreases in food consumption. Our results generally support the premise that fishes in rivers and lakes of the southern United States (U.S.) have inherently greater potential to impact zebra mussels by predation. Our simulations may provide a partial explanation of why zebra mussel invasions have not been as rapid and widespread in southern U.S. waters compared to the Great Lakes region. ?? Blackwell Munksgaard, 2004.

  16. Use of alternating and pulsed direct current electrified fields for zebra mussel control

    USGS Publications Warehouse

    Luoma, James A.; Dean, Jan C.; Severson, Todd J.; Wise, Jeremy K.; Barbour, Matthew

    2017-01-01

    Alternatives to chemicals for controlling dreissenid mussels are desirable for environmental compatibility, but few alternatives exist. Previous studies have evaluated the use of electrified fields for stunning and/or killing planktonic life stages of dreissenid mussels, however, the available literature on the use of electrified fields to control adult dreissenid mussels is limited. We evaluated the effects of sinusoidal alternating current (AC) and 20% duty cycle square-wave pulsed direct current (PDC) exposure on the survival of adult zebra mussels at water temperatures of 10, 15, and 22 °C. Peak voltage gradients of ~ 17 and 30 Vp/cm in the AC and PDC exposures, respectively, were continuously applied for 24, 48, or 72 h. Peak power densities ranged from 77,999 to 107,199 µW/cm3 in the AC exposures and 245,320 to 313,945 µW/cm3 in the PDC exposures. The peak dose ranged from 6,739 to 27,298 Joules/cm3 and 21,306 to 80,941 Joules/cm3 in the AC and PDC exposures, respectively. The applied power ranged from 16.6 to 68.9 kWh in the AC exposures and from 22.2 to 86.4 kWh in the PDC exposures. Mortality ranged from 2.7 to 92.7% in the AC exposed groups and from 24.0 to 98.7% in PDC exposed groups. Mortality increased with corresponding increases in water temperature and exposure duration, and we observed more zebra mussel mortality in the PDC exposures. Exposures conducted with AC required less of a peak dose (Joules/cm3) but more applied power (kWh) to achieve the same level of adult zebra mussel mortality as corresponding PDC exposures. The results demonstrate that 20% duty cycle square-wave PDC requires less energy than sinusoidal AC to inducing the same level of adult zebra mussel mortality.

  17. Bioassessment of mercury, cadmium, polychlorinated biphenyls, and pesticides in the upper Mississippi river with Zebra mussels (Dreissena polymorpha)

    USGS Publications Warehouse

    Cope, W. Gregory; Bartsch, Michelle; Rada, Ronald G.; Balogh, Steven J.; Rupprecht, John E.; Young, R. David; Johnson, D. Kent

    1999-01-01

    Zebra mussels (Dreissena polymorpha) were sampled from artificial substrates deployed from May 30 to October 19, 1995, at 19 locks and dams from Minneapolis, MN, to Muscatine, IA. Analyses of composite tissue samples of zebra mussels (10−20-mm length) revealed accumulation of mercury (Hg), cadmium (Cd), and polychlorinated biphenyls (PCBs) during a 143-d exposure period. Concentrations of total Hg ranged from 2.6 to 6.1 ng/g wet weight and methylmercury (CH3Hg) from 1.0 to 3.3 ng/g wet weight. About 50% (range 30−70%) of the mean total Hg in zebra mussels was CH3Hg. Cadmium ranged from 76 to 213 ng/g wet weight. Concentrations of total PCBs (Aroclor 1254) in zebra mussels varied longitudinally (range 1000−7330 ng/g lipid weight), but the composition of PCB congeners (total of 21 measured) was similar throughout the river. Chlordane and dieldrin were the only two pesticides detected of the 15 analyzed. Zebra mussels are sentinels of contaminant bioavailability in the Upper Mississippi River and may be an important link in the trophic transfer of contaminants in the river because of their increasing importance in the diets of certain fish and waterfowl.

  18. Body size-dependent Cd accumulation in the zebra mussel Dreissena polymorpha from different routes.

    PubMed

    Tang, Wen-Li; Evans, Douglas; Kraemer, Lisa; Zhong, Huan

    2017-02-01

    Understanding body size-dependent metal accumulation in aquatic organisms (i.e., metal allometry) is critical in interpreting biomonitoring data. While growth has received the most attention, little is known about controls of metal exposure routes on metal allometry. Here, size-dependent Cd accumulation in zebra mussels (Dreissena polymorpha) from different routes were investigated by exposing mussels to A.( 111 Cd spiked algae+ 113 Cd spiked river water) or B.( 111 Cd spiked sediments+ 113 Cd spiked river water). After exposure, 111 Cd or 113 Cd levels in mussel tissue were found to be negatively correlated with tissue weight, while Cd allometry coefficients (b values) were dependent on Cd exposure routes: -0.664 for algae, -0.241 for sediments and -0.379 for river water, compared to -0.582 in un-exposed mussels. By comparing different Cd exposure routes, we found that size-dependent Cd bioaccumulation from algae or river water could be more responsible for the overall size-dependent Cd accumulation in mussels, and the relative importance of the two sources was dependent on mussel size ranges: Cadmium obtained from algae (algae-Cd) was more important in size-dependent Cd accumulation in smaller mussels (tissue dry weight < 5 mg), while river water-Cd became more important in larger individuals (tissue dry weight > 5 mg). In contrast, sediment-Cd contributed only a small amount to Cd accumulation in zebra mussels and may have little effect on size-dependent Cd bioaccumulation. Our results suggest that size-dependent Cd accumulation in mussels could be largely affected by exposure routes, which should be considered when trying to interpret Cd biomonitoring data of zebra mussels. Copyright © 2016 Elsevier Ltd. All rights reserved.

  19. Zebra Mussel Chemical Control Guide, Version 2.0

    DTIC Science & Technology

    2015-07-01

    delivery systems, including potable water treatment, agriculture, industry, power generation, and fire protection. Since this invasive organism’s...delivery systems, including potable water treatment, agriculture, industry, power generation, and fire protection (Mackie and Claudi 2010). Zebra mussels...generators, pipes, valves, sensing equipment (level, flow, and pressure) and fire protection (Mackie and Claudi 2010; Prescott et al. 2014). Other USACE

  20. Involvement of Apoptosis in Host-Parasite Interactions in the Zebra Mussel

    PubMed Central

    Minguez, Laëtitia; Brulé, Nelly; Sohm, Bénédicte; Devin, Simon; Giambérini, Laure

    2013-01-01

    The question of whether cell death by apoptosis plays a biological function during infection is key to understanding host-parasite interactions. We investigated the involvement of apoptosis in several host-parasite systems, using zebra mussels Dreissena polymorpha as test organisms and their micro- and macroparasites. As a stress response associated with parasitism, heat shock proteins (Hsp) can be induced. In this protein family, Hsp70 are known to be apoptosis inhibitors. Mussels were diagnosed for their respective infections by standard histological methods; apoptosis was detected using the TUNEL methods on paraffin sections and Hsp70 by immunohistochemistry on cryosections. Circulating hemocytes were the main cells observed in apoptosis whereas infected tissues displayed no or few apoptotic cells. Parasitism by intracellular bacteria Rickettsiales-like and the trematode Bucephalus polymorphus were associated with the inhibition of apoptosis whereas ciliates Ophryoglena spp. or the trematode Phyllodistomum folium did not involve significant differences in apoptosis. Even if some parasites were able to modulate apoptosis in zebra mussels, we did not see evidence of any involvement of Hsp70 on this mechanism. PMID:23785455

  1. A food web modeling analysis of a Midwestern, USA eutrophic lake dominated by non-native Common Carp and Zebra Mussels

    USGS Publications Warehouse

    Colvin, Michael E.; Pierce, Clay; Stewart, Timothy W.

    2015-01-01

    Food web modeling is recognized as fundamental to understanding the complexities of aquatic systems. Ecopath is the most common mass-balance model used to represent food webs and quantify trophic interactions among groups. We constructed annual Ecopath models for four consecutive years during the first half-decade of a zebra mussel invasion in shallow, eutrophic Clear Lake, Iowa, USA, to evaluate changes in relative biomass and total system consumption among food web groups, evaluate food web impacts of non-native common carp and zebra mussels on food web groups, and to interpret food web impacts in light of on-going lake restoration. Total living biomass increased each year of the study; the majority of the increase due to a doubling in planktonic blue green algae, but several other taxa also increased including a more than two-order of magnitude increase in zebra mussels. Common carp accounted for the largest percentage of total fish biomass throughout the study even with on-going harvest. Chironomids, common carp, and zebra mussels were the top-three ranking consumer groups. Non-native common carp and zebra mussels accounted for an average of 42% of the total system consumption. Despite the relatively high biomass densities of common carp and zebra mussel, food web impacts was minimal due to excessive benthic and primary production in this eutrophic system. Consumption occurring via benthic pathways dominated system consumption in Clear Lake throughout our study, supporting the argument that benthic food webs are significant in shallow, eutrophic lake ecosystems and must be considered if ecosystem-level understanding is to be obtained.

  2. Making the Best of a Pest: The Potential for Using Invasive Zebra Mussel ( Dreissena Polymorpha) Biomass as a Supplement to Commercial Chicken Feed

    NASA Astrophysics Data System (ADS)

    McLaughlan, Claire; Rose, Paul; Aldridge, David C.

    2014-11-01

    Invasive non-native species frequently occur in very high densities. When such invaders present an economic or ecological nuisance, this biomass is typically removed and landfill is the most common destination, which is undesirable from both an economic and ecological perspective. The zebra mussel, Dreissena polymorpha, has invaded large parts of Europe and North America, and is routinely removed from raw water systems where it creates a biofouling nuisance. We investigated the suitability of dried, whole zebra mussels as a supplement to poultry feed, thus providing a more attractive end-use than disposal to landfill. Measurable outcomes were nutrient and energy composition analyses of the feeds and production parameters of the birds over a 14 day period. Zebra mussels were a palatable feed supplement for chickens. The mussel meal contained high levels of calcium (344.9 g kg-1), essential for egg shell formation, which was absorbed and retained easily by the birds. Compared with standard feed, a mussel-supplemented diet caused no significant effects on production parameters such as egg weight and feed conversion ratio during the study period. However, protein and energy levels in the zebra mussel feed were much lower than expected from the literature. In order for zebra mussels to be a viable long-term feed supplement for poultry, flesh would need to be separated from the shells in an economically viable way. If zebra mussels were to be used with the shells remaining, it seems that the resultant mussel meal would be more suitable as a calcium supplement.

  3. Making the best of a pest: the potential for using invasive zebra mussel (Dreissena polymorpha) biomass as a supplement to commercial chicken feed.

    PubMed

    McLaughlan, Claire; Rose, Paul; Aldridge, David C

    2014-11-01

    Invasive non-native species frequently occur in very high densities. When such invaders present an economic or ecological nuisance, this biomass is typically removed and landfill is the most common destination, which is undesirable from both an economic and ecological perspective. The zebra mussel, Dreissena polymorpha, has invaded large parts of Europe and North America, and is routinely removed from raw water systems where it creates a biofouling nuisance. We investigated the suitability of dried, whole zebra mussels as a supplement to poultry feed, thus providing a more attractive end-use than disposal to landfill. Measurable outcomes were nutrient and energy composition analyses of the feeds and production parameters of the birds over a 14 day period. Zebra mussels were a palatable feed supplement for chickens. The mussel meal contained high levels of calcium (344.9 g kg(-1)), essential for egg shell formation, which was absorbed and retained easily by the birds. Compared with standard feed, a mussel-supplemented diet caused no significant effects on production parameters such as egg weight and feed conversion ratio during the study period. However, protein and energy levels in the zebra mussel feed were much lower than expected from the literature. In order for zebra mussels to be a viable long-term feed supplement for poultry, flesh would need to be separated from the shells in an economically viable way. If zebra mussels were to be used with the shells remaining, it seems that the resultant mussel meal would be more suitable as a calcium supplement.

  4. Efficacy of spray –Dried Pseudomonas fluorescens, strain CL145A (Zequanox®), for controlling Zebra Mussels (Dreissena polymorpha) within Lake Minnetonka, MN enclosures

    USGS Publications Warehouse

    Luoma, James A.; Severson, Todd J.

    2016-01-01

    The efficacy of whole water column and subsurface applications of the biopesticide Zequanox®, a commercially prepared spray-dried powder formulation of Pseudomonas fluorescens (strain CL145A), were evaluated for controlling zebra mussels (Dreissena polymorpha) within 27-m2 enclosures in Lake Minnetonka (Deephaven, Minnesota). Five treatments consisting of (1) two whole water column Zequanox applications, (2) two subsurface Zequanox applications, and (3) an untreated control were completed on each of three independent treatment days during September 2014. The two types of samplers used in the study were (1) type 1 samplers, which were custom built multi-plate samplers (wood, perforated aluminum, and tile substrates) that were placed into Robinson’s Bay in June of 2013 to allow for natural colonization by zebra mussels, and (2) type 2 samplers, which consisted of zebra mussels adhering to perforated aluminum trays that were placed into mesh containment bags. One day prior to treatment, three individual samplers of each type were distributed to test enclosures and exposed to a randomly assigned treatment. Sampling to determine the zebra mussel biomass adhering to type 1 samplers and the survival assessments for zebra mussels contained in type 2 samplers were completed ~40 days after exposure. The zebra mussel biomass adhering to type 1 samplers and the survival of zebra mussels contained in type 2 samplers were significantly less in groups treated with the highest Zequanox concentrations and in groups that received whole water column applications than comparable groups treated with lower Zequanox concentrations and subsurface applications. However, standardization of biomass and survival results to the amount of Zequanox applied showed that the lower concentrations and subsurface applications were more cost efficient, with respect to product used, at reducing zebra mussel biomass and for inducing zebra mussel mortality. Although the subsurface application methods

  5. In situ growth of juvenile zebra mussels in a regulated stream

    USGS Publications Warehouse

    French, John R. P.; Nichols, S. Jerrine; Craig, Jaquelyn M.; Allen, Jeffery D.; Black, M. Glen

    2006-01-01

    We investigated the in situ growth of juvenile zebra mussels (Dreissena polymorpha) in a reach of the Huron River (southeast Michigan) below a dam with a control gate that regulates water levels. Growth was significantly different among sample dates over a five-month-long monitoring season. Mean growth of mussels generally decreased from 0.093 mm/day just above the dam to 0.067 mm/day 4 km downstream, then increased to 0.091 mm/day at end of the 17-km-long study area. Significant differences among sites were most numerous in August during a severe drought when discharges fell substantially. Growth was positively correlated with discharges (R2 = 0.94, p a levels in the study area, however, was weak (R2 = 0.69, p < 0.1). Our study suggests that discharge may be one controlling factor for dreissenid populations in small streams.

  6. Book review: Biology and management of invasive quagga and zebra mussels in the western United States

    USGS Publications Warehouse

    Benson, Amy J.

    2017-01-01

    Water is a precious and limited commodity in the western United States and its conveyance is extremely important. Therefore, it is critical to do as much as possible to prevent the spread of two species of dreissenid mussels, both non-native and highly invasive aquatic species already well-established in the eastern half of the United States. This book addresses the occurrences of the two dreissenid mussels in the West, the quagga mussel and the zebra mussel, that are both known to negatively impact water delivery systems and natural ecosystems. It is edited by two researchers whom have extensive experience working with the mussels in the West and is composed of 34 chapters, or articles, written by a variety of experts.Book information: Biology and Management of Invasive Quagga and Zebra Mussels in the Western United States. Edited by Wai Hing Wong and Shawn L. Gerstenberger. Boca Raton (Florida): CRC Press (Taylor & Francis Group). $149.95. xx + 545 p.; ill.; index. ISBN: 978-1-4665-9561-3. [Compact Disc included.] 2015.

  7. Zebra mussel beds: an effective feeding ground for Ponto-Caspian gobies or suitable shelter for their prey?

    PubMed

    Kobak, Jarosław; Poznańska, Małgorzata; Jermacz, Łukasz; Kakareko, Tomasz; Prądzynski, Daniel; Łodygowska, Małgorzata; Montowska, Karolina; Bącela-Spychalska, Karolina

    2016-01-01

    Aggregations of the Ponto-Caspian invasive zebra mussel ( Dreissena polymorpha ) constitute a suitable habitat for macroinvertebrates, considerably increasing their abundance and providing effective antipredator protection. Thus, the overall effect of a mussel bed on particular predator species may vary from positive to negative, depending on both prey density increase and predator ability to prey in a structurally complex habitat. Alien Ponto-Caspian goby fish are likely to be facilitated when introduced into new areas by zebra mussels, provided that they are capable of utilizing mussel beds as habitat and feeding grounds. We ran laboratory experiments to find which prey (chironomid larvae) densities (from ca. 500 to 2,000 individuals m -2 ) in a mussel bed make it a more beneficial feeding ground for the racer goby Babka gymnotrachelus (RG) and western tubenose goby Proterorhinus semilunaris (WTG) compared to sandy and stone substrata (containing the basic prey density of 500 ind. m -2 ). Moreover, we checked how food availability affects habitat selection by fish. Mussel beds became more suitable for fish than alternative mineral substrata when food abundance was at least two times higher (1,000 vs. 500 ind. m -2 ), regardless of fish size and species. WTG was associated with mussel beds regardless of its size and prey density, whereas RG switched to this habitat when it became a better feeding ground than alternative substrata. Larger RG exhibited a stronger affinity for mussels than small individuals. WTG fed more efficiently from a mussel bed at high food abundances than RG. A literature review has shown that increasing chironomid density, which in our study was sufficient to make a mussel habitat an attractive feeding ground for the gobies, is commonly observed in mussel beds in the field. Therefore, we conclude that zebra mussels may positively affect the alien goby species and are likely to facilitate their establishment in novel areas, contributing to an

  8. Early responses to zebra mussels in the Great Lakes: a journey from information vacuum to policy and regulation

    USGS Publications Warehouse

    Griffiths, Ronald W.; Schloesser, Don W.; Kovalak, William P.

    2013-01-01

    Invasive species such as zebra mussels pose a threat to the economies and environments of coastal and fresh-water habitats around the world. Consequently, it is important that government policies and programs be adequate to protect these waters from invaders. This chapter documents key events that took place in the early years (1988-1991) of zebra mussel colonization of the Laurentian Great Lakes and evaluates government responses (policies and programs) to this disruptive, invasive, freshwater species.

  9. The zebra mussel (Dreissena polymorpha), a new pest in North America: reproductive mechanisms as possible targets of control strategies

    USGS Publications Warehouse

    Ram, Jeffrey L.; Fong, Peter; Croll, Roger P.; Nichols, Susan J.; Wall, Darcie

    1992-01-01

    The zebra mussel (Dreissena polymorpha) has spread rapidly in temperate fresh waters of North America since its introduction into the Great Lakes in 1985 or 1986. It attaches to hard substrates, forming layers, occluding water intakes, encrusting and killing native mussels, filtering algae in competition with other planktivores, and possibly interfering with fish spawning. It reproduces prolifically, suggesting that an approach to its control may be by controlling its reproduction. Previous literature suggests that spawning in bivalves is regulated by both environmental and internal chemical cues. A suggested sequence is that phytoplankton chemicals initially trigger spawning; chemicals associated with gametes provide a species-specific pheromonal positive feedback for spawning; and the response to environmental chemicals is mediated internally by serotonin (5-HT). The role of 5-HT in zebra mussels is under investigation. Both males and females can be induced to spawn by either injection or external application of 5-HT. The response can also be activated by 8-hydroxy-2-(di-n-propylamino)-tetralin, an agonist at 5-HT1A receptors. HPLC analysis has detected 5-HT as the major biogenic amine in both male and female gonads. 5-HT immunocytochemistry demonstrates nerves containing serotonergic fibers innervating gonads of both males and females, with prominent varicosities surrounding the follicles in both sexes. A role of 5-HT in mediating spawning responses in zebra mussels is thus strongly supported. These studies have shown that reproductive behavior of zebra mussels can be modified by outside chemicals, a property that may be exploited for purposes of control.

  10. Comparative morphology of zebra (Dreissena polymorpha) and quagga (Dreissena bugensis) mussel sperm: Light and electron microscopy

    USGS Publications Warehouse

    Walker, G.K.; Black, M.G.; Edwards, C.A.

    1996-01-01

    Adult zebra (Dreissena polymorpha) and quagga (Dreissena bugensis) mussels were induced to release large quantities of live spermatozoa by the administration of 5-hydroxytryptamine (serotonin). Sperm were photographed alive using phase-contrast microscopy and were fixed subsequently with glutaraldehyde followed by osmium tetroxide for eventual examination by transmission or scanning electron microscopy. The sperm of both genera are of the ect-aquasperm type. Their overall dimensions and shape allow for easy discrimination at the light and scanning electron microscopy level. Transmission electron microscopy of the cells reveals a barrel-shaped nucleus in zebra mussel sperm and an elongated nucleus in quagga mussel sperm. In both species, an acrosome is cradled in a nuclear fossa. The ultrastructure of the acrosome and axial body, however, is distinctive for each species. The structures of the midpiece are shown, including a unique mitochondrial "skirt" that includes densely packed parallel cristae and extends in a narrow sheet from the mitochondria.

  11. Preliminary characterization of digestive enzymes in freshwater mussels

    USGS Publications Warehouse

    Sauey, Blake W.; Amberg, Jon J.; Cooper, Scott T.; Grunwald, Sandra K.; Newton, Teresa J.; Haro, Roger J.

    2015-01-01

    Resource managers lack an effective chemical tool to control the invasive zebra mussel Dreissena polymorpha. Zebra mussels clog water intakes for hydroelectric companies, harm unionid mussel species, and are believed to be a reservoir of avian botulism. Little is known about the digestive physiology of zebra mussels and unionid mussels. The enzymatic profile of the digestive glands of zebra mussels and native threeridge (Amblema plicata) and plain pocketbook mussels (Lampsilis cardium) are characterized using a commercial enzyme kit, api ZYM, and validated the kit with reagent-grade enzymes. A linear correlation was shown for only one of nineteen enzymes, tested between the api ZYM kit and a specific enzyme kit. Thus, the api ZYM kit should only be used to make general comparisons of enzyme presence and to observe trends in enzyme activities. Enzymatic trends were seen in the unionid mussel species, but not in zebra mussels sampled 32 days apart from the same location. Enzymatic classes, based on substrate, showed different trends, with proteolytic and phospholytic enzymes having the most change in relative enzyme activity.

  12. The Effects of Zebra Mussels (Dreissena polymorpha) on the Foraging Success of Eurasian Perch (Perca fluviatilis) and Ruffe (Gymnocephalus cernuus)

    NASA Astrophysics Data System (ADS)

    Dieterich, Axel; Mörtl, Martin; Eckmann, Reiner

    2004-07-01

    Complex habitat structures can influence the foraging success of fish. Competition for food between fish species can therefore depend on the competitors' abilities to cope with structural complexity. In laboratory experiments, we comparatively assessed effects of zebra mussels (Dreissena polymorpha Pall.) on the foraging success of Eurasian perch (Perca fluviatilis L.) and ruffe (Gymnocephalus cernuus (L.)). In single-species and mixed-species experiments, the fish were fed caddisfly larvae (Tinodes waeneri (L.)) over complex (mussel-covered stones) and less-complex (bare stones) substrates. With intraspecific competition, food consumption by perch and ruffe decreased significantly when the complex substrate was used. With interspecific competition, food consumption by perch and ruffe did not change with substrate complexity, but perch clearly out-competed ruffe on both substrates. Zebra mussel beds provide a refuge for macrozoobenthos against predation by ruffe and probably also by perch. (

  13. Genotoxic effects induced by the exposure to an environmental mixture of illicit drugs to the zebra mussel.

    PubMed

    Parolini, Marco; Magni, Stefano; Castiglioni, Sara; Binelli, Andrea

    2016-10-01

    Despite the growing interest on the presence of illicit drugs in freshwater ecosystems, just recently the attention has been focused on their potential toxicity towards non-target aquatic species. However, these studies largely neglected the effects induced by exposure to complex mixtures of illicit drugs, which could be different compared to those caused by single psychoactive molecules. This study was aimed at investigating the genetic damage induced by a 14-day exposure to a realistic mixture of the most common illicit drugs found in surface waters worldwide (cocaine, benzoylecgonine, amphetamine, morphine and 3,4-methylenedioxymethamphetamine) on the zebra mussel (Dreissena polymorpha). The mixture caused a significant increase of DNA fragmentation and triggered the apoptotic process and micronuclei formation in zebra mussel hemocytes, pointing out its potential genotoxicity towards this bivalve species. Copyright © 2016 Elsevier Inc. All rights reserved.

  14. Invasive zebra mussels (Driessena polymorpha) and Asian clams (Corbicula fluminea) survive gut passage of migratory fish species: implications for dispersal

    USGS Publications Warehouse

    Gatlin, Michael R.; Shoup, Daniel E.; Long, James M.

    2013-01-01

    The introduction and spread of invasive species is of great concern to natural resource managers in the United States. To effectively control the spread of these species, managers must be aware of the multitude of dispersal methods used by the organisms. We investigated the potential for survival through the gut of a migrating fish (blue catfish, Ictalurus furcatus) as a dispersal mechanism for two invasive bivalves: zebra mussel (Driessena polymorpha) and Asian clam (Corbicula fluminea). Blue catfish (N = 62) were sampled over several months from Sooner Lake, Oklahoma, transported to a laboratory and held in individual tanks for 48 h. All fecal material was collected and inspected for live mussels. Survival was significantly related to water temperature in the lake at the time of collection, with no mussels surviving above 21.1 C°, whereas 12 % of zebra mussels (N = 939) and 39 % of Asian clams (N = 408) consumed in cooler water survived gut passage. This research demonstrates the potential for blue catfish to serve as a dispersal vector for invasive bivalves at low water temperatures.

  15. Spawning of zebra mussels (Dreissena polymorpha) and rearing of veligers under laboratory conditions

    USGS Publications Warehouse

    Nichols, S. Jerrine; Nalepa, Thomas F.; Schloesser, Donald W.

    1992-01-01

    The spawning cycle of the zebra mussel, Dreissena polymorpha, is amenable to laboratory manipulations. Techniques are presented that can be used to initiate spawning and rear veligers from fertilized egg to settlement stage. Spawning can be induced in sexually mature mussels by temperature flucuations or by the addition of ripe gametes. Embryonic survival is excellent until the straight-hinge stage when the first wave of mortality occurs, usually due to improper food. The second critical stage of development occurs just prior to settlement when mortality increases again. Veliger mortality averaged over 90% from egg to settlement. The results indicate that obtaining large numbers of veligers for laboratory experiments to be conducted year-round is difficult.

  16. A cost-benefit analysis of preventative management for zebra and quagga mussels in the Colorado-Big Thompson System

    USGS Publications Warehouse

    Thomas, Catherine M.

    2010-01-01

    Zebra and quagga mussels are fresh water invaders that have the potential to cause severe ecological and economic damage. It is estimated that mussels cause $1 billion dollars per year in damages to water infrastructure and industries in the United States (Pimentel et al., 2004). Following their introduction to the Great Lakes in the late 1980s, mussels spread rapidly throughout the Mississippi River Basin and the Eastern U.S. The mussel invasion in the West is young. Mussels were first identified in Nevada in 2007, and have since been identified in California, Arizona, Colorado, Utah, and Texas. Western water systems are very different from those found in the East. The rapid spread of mussels through the eastern system was facilitated by connected and navigable waterways. Western water systems are less connected and are characterized by man-made reservoirs and canals. The main vector of spread for mussels in the West is overland on recreational boats (Bossenbroek et al., 2001). In response to the invasion, many western water managers have implemented preventative management programs to slow the overland spread of mussels on recreational boats. In Colorado, the Colorado Department of Wildlife (CDOW) has implemented a mandatory boat inspection program that requires all trailered boats to be inspected before launching in any Colorado water body. The objective of this study is to analyze the costs and benefits of the CDOW boat inspection program in Colorado, and to identify variables that affect the net benefits of preventative management. Predicting the potential economic benefits of slowing the spread of mussels requires integrating information about mussel dispersal potential with estimates of control costs (Keller et al., 2009). Uncertainty surrounding the probabilities of establishment, the timing of invasions, and the damage costs associated with an invasion make a simulation model an excellent tool for addressing "what if" scenarios and shedding light on the

  17. Canal construction destroys the barrier between major European invasion lineages of the zebra mussel.

    PubMed Central

    Müller, Jakob C; Hidde, Dennis; Seitz, Alfred

    2002-01-01

    Since the mid-1980s the zebra mussel, Dreissena polymorpha, Pallas 1771, has become the protagonist of a spectacular freshwater invasion in North America due to its large economic and biological impact. Several genetic studies on American populations have failed to detect any large-scale geographical patterns. In western Europe, where D. polymorpha has been a classical invader from the Pontocaspian since the early 19th century, the situation is strikingly different. Here, we show with genetic markers that two major western European invasion lineages with lowered genetic variability within and among populations can be discriminated. These two invasion lineages correspond with two separate navigable waterways to western Europe. We found a rapid and asymmetrical genetic interchange of the two invasion lines after the construction of the Main-Danube canal in 1992, which interconnected the two waterways across the main watershed. PMID:12061957

  18. Nutrient Recycling Impacts by Zebra Mussels in Harper’s Ferry Slough, Upper Mississippi River

    DTIC Science & Technology

    2000-12-01

    ing pro duc tiv ity in the slough (also see Caraco et al. (1997)). In Harper’s Ferry Slough and other aquatic sys tems, the mag ni tude of ze bra mus...the Upper Mississippi River with zebra mussels (Dreissena polymorpha),” Environ. Sci. Technol. 33, 4385-4390. ERDC WQTN-PD-07 December 2000 11 Caraco , N

  19. Pseudomonas fluorescens strain CL145A - a biopesticide for the control of zebra and quagga mussels (Bivalvia: Dreissenidae).

    PubMed

    Molloy, Daniel P; Mayer, Denise A; Gaylo, Michael J; Morse, John T; Presti, Kathleen T; Sawyko, Paul M; Karatayev, Alexander Y; Burlakova, Lyubov E; Laruelle, Franck; Nishikawa, Kimi C; Griffin, Barbara H

    2013-05-01

    Zebra mussels (Dreissena polymorpha) and quagga mussels (Dreissena rostriformis bugensis) are the "poster children" of high-impact aquatic invasive species. In an effort to develop an effective and environmentally acceptable method to control their fouling of raw-water conduits, we have investigated the potential use of bacteria and their natural metabolic products as selective biological control agents. An outcome of this effort was the discovery of Pseudomonas fluorescens strain CL145A - an environmental isolate that kills these dreissenid mussels by intoxication (i.e., not infection). In the present paper, we use molecular methods to reconfirm that CL145A is a strain of the species P. fluorescens, and provide a phylogenetic analysis of the strain in relation to other Pseudomonas spp. We also provide evidence that the natural product lethal to dreissenids is associated with the cell wall of P. fluorescens CL145A, is a heat-labile secondary metabolite, and has degradable toxicity within 24 h when applied to water. CL145A appears to be an unusual strain of P. fluorescens since it was the only one among the ten strains tested to cause high mussel mortality. Pipe trials conducted under once-through conditions indicated: (1) P. fluorescens CL145A cells were efficacious against both zebra and quagga mussels, with high mortalities achieved against both species, and (2) as long as the total quantity of bacterial cells applied during the entire treatment period was the same, similar mussel mortality could be achieved in treatments lasting 1.5-12.0 h, with longer treatment durations achieving lower mortalities. The efficacy data presented herein, in combination with prior demonstration of its low risk of non-target impact, indicate that P. fluorescens CL145A cells have significant promise as an effective and environmentally safe control agent against these invasive mussels. Copyright © 2012 Elsevier Inc. All rights reserved.

  20. Lessons from a transplantation of zebra mussels into a small urban river: An integrated ecotoxicological assessment.

    PubMed

    Bourgeault, A; Gourlay-Francé, C; Vincent-Hubert, F; Palais, F; Geffard, A; Biagianti-Risbourg, S; Pain-Devin, S; Tusseau-Vuillemin, M-H

    2010-10-01

    It is often difficult to evaluate the level of contamination in small urban rivers because pollution is mainly diffuse, with low levels of numerous substances. The use of a coupled approach using both chemical and biological measurements may provide an integrated evaluation of the impact of micro-pollution on the river. Zebra mussels were transplanted along a metal and organic pollution gradient in spring 2008. For two months, mussels and water samples were collected from two sites every two weeks and analyzed for metal and PAH content as well as water physicochemical parameters. Diffusive gradients in thin film (DGT) were also used to assess levels of labile metals. Exposure of mussels to contaminants and potential impact were evaluated using physiological indices and various biomarkers including condition index (CI), defense mechanisms (glutathione-S-transferase: GST), digestive enzymes (amylase and cellulase) and genotoxicity (micronucleus test: MN and comet assay: CA). For most contaminants, the water contamination was significantly higher downstream. Bioaccumulation in zebra mussels was related to water contamination in the framework of the biodynamic model, which allowed us to take into account the biological dilution that was caused by the growth of soft tissue downstream. Thus, metal influxes were on average two times higher downstream than upstream in particular for Zn, Cr, Cu and Cd. Significant differences in condition index were observed (final CI was 0.42 ± 0.03 downstream and 0.31 ± 0.03 upstream) reflecting a better food availability downstream. Moreover a significant decrease of GST activity and digestive enzymes activity in the cristalline style was observed downstream. Interpreting this decrease requires considering not only micro-pollution but also the trophic status related to the water's physicochemistry. The MN test and the CA on gill cells highlighted genotoxicity in mussels transplanted downstream compared to upstream. © 2010 Wiley

  1. Underwater cleaning techniqued used for removal of zebra mussels at the FitzPatrick Nuclear Power Plant

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Hobbs, B.; Kahabka, J.

    1995-06-01

    This paper discusses the use of a mechanical brush cleaning technology recently used to remove biofouling from the Circulating Water (CW) System at New York Power Authority`s James A. FitzPatrick Nuclear Power Plant. The FitzPatrick plant had previously used chemical molluscicide to treat zebra mussels in the CW system. Full system treatment was performed in 1992 with limited forebay/screenwell treatment in 1993. The New York Power Authority (NYPA) decided to conduct a mechanical cleaning of the intake system in 1994. Specific project objectives included: (1) Achieve a level of surface cleaniness greater than 98%; (2) Remove 100% of debris, bothmore » existing sediment and debris generated as a result of cleaning; (3) Inspect all surfaces and components, identifying any problem areas; (4) Complete the task in a time frame within the 1994-95 refueling outage schedule window, and; (5) Determine if underwater mechanical cleaning is a cost-effective zebra mussel control method suitable for future application at FitzPatrick. A pre-cleaning inspection, including underwater video photography, was conducted of each area. Cleaning was accomplished using diver-controlled, multi-brush equipment included the electro-hydraulic powered Submersible Cleaning and Maintenance Platform (SCAMP), and several designs of hand-held machines. The brushes swept all zebra mussels off surfaces, restoring concrete and metal substrates to their original condition. Sensitive areas including pump housings, standpipes, sensor piping and chlorine injection tubing, were cleaned without degradation. Submersible vortex vacuum pumps were used to remove debris from the cavity. More than 46,000 ft{sup 2} of surface area was cleaned and over 460 cubic yards of dewatered debris were removed. As each area was completed, a post-clean inspection with photos and video was performed.« less

  2. Modelling the Risk Posed by the Zebra Mussel Dreissena polymorpha: Italy as a Case Study

    NASA Astrophysics Data System (ADS)

    Bosso, Luciano; De Conno, Carmelina; Russo, Danilo

    2017-08-01

    We generated a risk map to forecast the potential effects of the spreading of zebra mussels Dreissena polymorpha across the Italian territory. We assessed the invader's potential impact on rivers, lakes, watersheds and dams at a fine-grained scale and detected those more at risk that should be targeted with appropriate monitoring. We developed a MaxEnt model and employed weighted overlay analyses to detect the species' potential distribution and generate risk maps for Italy. D. polymorpha has a greater probability of occurring at low to medium altitudes in areas characterised by fluviatile deposits of major streams. Northern and central Italy appear more at risk. Some hydroelectric power dams are at high risk, while most dams for irrigation, drinkable water reservoirs and other dam types are at medium to low risk. The lakes and rivers reaches (representing likely expansion pathways) at medium-high or high risk mostly occur in northern and central Italy. We highlight the importance of modelling potential invasions on a country scale to achieve the sufficient resolution needed to develop appropriate monitoring plans and prevent the invader's harmful effects. Further high-resolution risk maps are needed for other regions partly or not yet colonised by the zebra mussel.

  3. Organochlorine and trace element contamination in wintering and migrating diving ducks in the southern Great Lakes, USA, since the zebra mussel invasion

    USGS Publications Warehouse

    Custer, Christine M.; Custer, T.W.

    2000-01-01

    Because of the potential for increased trophic transfer of contaminants by zebra mussels (Dreissena sp.) to higher trophic levels, we collected four species of waterfowl (n = 65 ducks) from four locations in Lake Erie, Lake St. Clair, and Lake Michigan, USA, between 1991 and 1993 for organochlorine contaminant and trace element analyses. Geometric mean concentrations of total polychlorinated biphenyls (PCBs) and p,pa??-dichlorodiphenyldichloroethylene (DDE) were 1.35 and 0.15 I?g/g wet weight in lesser scaup (Aythya affinis) carcasses and were below known effect levels. Total PCBs in 80% of carcasses, however, were above the U.S. Food and Drug Administration's threshold of 3.0 I?g/g lipid weight for consumption of poultry. With the exception of selenium, trace elements were also at background or no-effect levels. Selenium concentrations in livers of 95% of lesser scaup, 90% of bufflehead (Bucephala albeola), and 72% of common goldeneye (Bucephala clangula) were in the elevated (>10 I?g/g dry wt) or potentially harmful range (>33 I?g/g dry wt). The effects of these high selenium concentrations are unknown but should be investigated further based on reproductive effects observed in field and laboratory studies of dabbling ducks and because lesser scaup populations are declining. Concentrations of total PCBs in dreissenid mussels in western Lake Erie were 10 times higher than in the upper Mississippi River but were similar to concentrations in other industrialized rivers in Europe and the United States. Metal concentrations were similar to other industrialized sites where zebra mussels have been sampled.

  4. Mussel dynamics model: A hydroinformatics tool for analyzing the effects of different stressors on the dynamics of freshwater mussel communities

    USGS Publications Warehouse

    Morales, Y.; Weber, L.J.; Mynett, A.E.; Newton, T.J.

    2006-01-01

    A model for simulating freshwater mussel population dynamics is presented. The model is a hydroinformatics tool that integrates principles from ecology, river hydraulics, fluid mechanics and sediment transport, and applies the individual-based modelling approach for simulating population dynamics. The general model layout, data requirements, and steps of the simulation process are discussed. As an illustration, simulation results from an application in a 10 km reach of the Upper Mississippi River are presented. The model was used to investigate the spatial distribution of mussels and the effects of food competition in native unionid mussel communities, and communities infested by Dreissena polymorpha, the zebra mussel. Simulation results were found to be realistic and coincided with data obtained from the literature. These results indicate that the model can be a useful tool for assessing the potential effects of different stressors on long-term population dynamics, and consequently, may improve the current understanding of cause and effect relationships in freshwater mussel communities. ?? 2006 Elsevier B.V. All rights reserved.

  5. Pharyngeal teeth of the freshwater drum (Aplodinotus grunniens) a predator of the zebra mussel (Dreissena polymorpha)

    USGS Publications Warehouse

    French, John R. P.

    1997-01-01

    The morphology of pharyngeal teeth of freshwater drum (Aplodinotus grunniens) was studied to determine changes that occur during growth of drum that may relate to consumption of zebra mussel (Dreissena polymorpha) by larger fish. Pharyngeal teeth were of three types. Cardiform teeth were replaced by villiform teeth, which were replaced by molariform teeth as the size class of drum increased. Molariform teeth comprised over 85% of total surface area of dentition in fish 265 mm long.

  6. Effects of zebra mussels on food webs: Interactions with juvenile bluegill and water residence time

    USGS Publications Warehouse

    Richardson, W.B.; Bartsch, L.A.

    1997-01-01

    We evaluated how water residence time mediated the impact of zebra mussels Dreissena polymorpha and bluegill sunfish Lepomis macrochirus on experimental food webs established in 1100-1 outdoor mesocosms. Water residence time was manipulated as a surrogate for seston resupply - a critical variable affecting growth and survival of suspension-feeding invertebrates. We used a 2 x 2 x 2 factorial experimental design with eight treatment combinations (3 replicates/treatment) including the presence or absence of Dreissena (2000 per m2), juvenile bluegill (40 per mesocosm), and short (1100 1 per d) or long (220 1 per d) water residence time. Measures of seston concentration (chlorophyll a, turbidity and suspended solids) were greater in the short- compared to long water-residence mesocosms, but intermediate in short water-residence mesocosms containing Dreissena. Abundance of rotifers (Keratella and Polyarthra) was reduced in Dreissena mesocosms and elevated in short residence time mesocosms. Cladocera abundance, in general, was unaffected by the presence of Dreissena; densities were higher in short-residence time mesocosms, and reduced in the presence of Lepomis. The growth of juvenile Lepomis were unaffected by Dreissena because of abundant benthic food. The final total mass of Dreissena was significantly greater in short- than long-residence mesocosms. Impacts of Dreissena on planktonic food webs may not only depend on the density of zebra mussels but also on the residence time of the surrounding water and the resupply of seston. ?? 1997 Kluwer Academic Publishers.

  7. Using Massive Parallel Sequencing for the Development, Validation, and Application of Population Genetics Markers in the Invasive Bivalve Zebra Mussel (Dreissena polymorpha)

    PubMed Central

    Peñarrubia, Luis; Sanz, Nuria; Pla, Carles; Vidal, Oriol; Viñas, Jordi

    2015-01-01

    The zebra mussel (Dreissena polymorpha, Pallas, 1771) is one of the most invasive species of freshwater bivalves, due to a combination of biological and anthropogenic factors. Once this species has been introduced to a new area, individuals form dense aggregations that are very difficult to remove, leading to many adverse socioeconomic and ecological consequences. In this study, we identified, tested, and validated a new set of polymorphic microsatellite loci (also known as SSRs, Single Sequence Repeats) using a Massive Parallel Sequencing (MPS) platform. After several pruning steps, 93 SSRs could potentially be amplified. Out of these SSRs, 14 were polymorphic, producing a polymorphic yield of 15.05%. These 14 polymorphic microsatellites were fully validated in a first approximation of the genetic population structure of D. polymorpha in the Iberian Peninsula. Based on this polymorphic yield, we propose a criterion for establishing the number of SSRs that require validation in similar species, depending on the final use of the markers. These results could be used to optimize MPS approaches in the development of microsatellites as genetic markers, which would reduce the cost of this process. PMID:25780924

  8. Competitive replacement of invasive congeners may relax impact on native species: Interactions among zebra, quagga, and native unionid mussels

    USGS Publications Warehouse

    Burlakova, Lyubov E.; Tulumello, Brianne L.; Karatayev, Alexander Y.; Krebs, Robert A.; Schloesser, Donald W.; Paterson, Wendy L.; Griffith, Traci A.; Scott, Mariah W.; Crail, Todd D.; Zanatta, David T.

    2014-01-01

    Determining when and where the ecological impacts of invasive species will be most detrimental and whether the effects of multiple invaders will be superadditive, or subadditive, is critical for developing global management priorities to protect native species in advance of future invasions. Over the past century, the decline of freshwater bivalves of the family Unionidae has been greatly accelerated by the invasion of Dreissena. The purpose of this study was to evaluate the current infestation rates of unionids by zebra (Dreissena polymorpha) and quagga (D. rostriformis bugensis) mussels in the lower Great Lakes region 25 years after they nearly extirpated native unionids. In 2011–2012, we collected infestation data for over 4000 unionids from 26 species at 198 nearshore sites in lakes Erie, Ontario, and St. Clair, the Detroit River, and inland Michigan lakes and compared those results to studies from the early 1990s. We found that the frequency of unionid infestation by Dreissena recently declined, and the number of dreissenids attached to unionids in the lower Great Lakes has fallen almost ten-fold since the early 1990s. We also found that the rate of infestation depends on the dominant Dreissena species in the lake: zebra mussels infested unionids much more often and in greater numbers. Consequently, the proportion of infested unionids, as well as the number and weight of attached dreissenids were lower in waterbodies dominated by quagga mussels. This is the first large-scale systematic study that revealed how minor differences between two taxonomically and functionally related invaders may have large consequences for native communities they invade.

  9. Competitive Replacement of Invasive Congeners May Relax Impact on Native Species: Interactions among Zebra, Quagga, and Native Unionid Mussels

    PubMed Central

    Burlakova, Lyubov E.; Tulumello, Brianne L.; Karatayev, Alexander Y.; Krebs, Robert A.; Schloesser, Donald W.; Paterson, Wendy L.; Griffith, Traci A.; Scott, Mariah W.; Crail, Todd; Zanatta, David T.

    2014-01-01

    Determining when and where the ecological impacts of invasive species will be most detrimental and whether the effects of multiple invaders will be superadditive, or subadditive, is critical for developing global management priorities to protect native species in advance of future invasions. Over the past century, the decline of freshwater bivalves of the family Unionidae has been greatly accelerated by the invasion of Dreissena. The purpose of this study was to evaluate the current infestation rates of unionids by zebra (Dreissena polymorpha) and quagga (D. rostriformis bugensis) mussels in the lower Great Lakes region 25 years after they nearly extirpated native unionids. In 2011–2012, we collected infestation data for over 4000 unionids from 26 species at 198 nearshore sites in lakes Erie, Ontario, and St. Clair, the Detroit River, and inland Michigan lakes and compared those results to studies from the early 1990s. We found that the frequency of unionid infestation by Dreissena recently declined, and the number of dreissenids attached to unionids in the lower Great Lakes has fallen almost ten-fold since the early 1990s. We also found that the rate of infestation depends on the dominant Dreissena species in the lake: zebra mussels infested unionids much more often and in greater numbers. Consequently, the proportion of infested unionids, as well as the number and weight of attached dreissenids were lower in waterbodies dominated by quagga mussels. This is the first large-scale systematic study that revealed how minor differences between two taxonomically and functionally related invaders may have large consequences for native communities they invade. PMID:25490103

  10. Exposure of zebra mussels to extracorporeal shock waves demonstrates formation of new mineralized tissue inside and outside the focus zone.

    PubMed

    Sternecker, Katharina; Geist, Juergen; Beggel, Sebastian; Dietz-Laursonn, Kristin; de la Fuente, Matias; Frank, Hans-Georg; Furia, John P; Milz, Stefan; Schmitz, Christoph

    2018-04-03

    The success rate of extracorporeal shock wave therapy (ESWT) for fracture nonunions in human medicine (i.e., radiographic union at six months after ESWT) is only approximately 75%. Detailed knowledge regarding the underlying mechanisms that induce bio-calcification after ESWT is limited. We analyzed the biological response within mineralized tissue of a new invertebrate model organism, the zebra mussel Dreissena polymorpha , after exposure with extracorporeal shock waves (ESWs). Mussels were exposed to ESWs with positive energy density of 0.4 mJ/mm 2 (A) or were sham exposed (B). Detection of newly calcified tissue was performed by exposing the mussels to fluorescent markers. Two weeks later, the A-mussels showed a higher mean fluorescence signal intensity within the shell zone than the B-mussels (p<0.05). Acoustic measurements revealed that the increased mean fluorescence signal intensity within the shell of the A-mussels was independent of the size and position of the focal point of the ESWs. These data demonstrate that induction of bio-calcification after ESWT may not be restricted to the region of direct energy transfer of ESWs into calcified tissue. The results of the present study are of relevance for better understanding of the molecular and cellular mechanisms that induce formation of new mineralized tissue after ESWT. © 2018. Published by The Company of Biologists Ltd.

  11. Characteristics of a refuge for native freshwater mussels (Bivalvia: Unionidae) in Lake St. Clair

    USGS Publications Warehouse

    McGoldrick, D.J.; Metcalfe-Smith, J. L.; Arts, M.T.; Schloesser, D.W.; Newton, T.J.; Mackie, G.L.; Monroe, E.M.; Biberhofer, J.; Johnson, K.

    2009-01-01

    The Lake St. Clair delta (??? 100??km2) provides an important refuge for native freshwater mussels (Unionidae) wherein 22 of the ??? 35 historical species co-occur with invasive dreissenids. A total of 1875 live unionids representing 22 species were found during snorkeling surveys of 32 shallow (??? 1??m) sites throughout the delta. Richness and density of unionids and zebra mussel infestation rates varied among sites from 3 to 13 unionid species, 0.02 to 0.12 unionids/m2, and < 1 to 35 zebra mussels/unionid, respectively. Zebra mussel infestation of unionids in the delta appears to be mitigated by dominant offshore currents, which limit densities of zebra mussel veligers in nearshore compared to offshore waters (13,600 vs. 28,000/m3, respectively). Glycogen concentrations in the tissues of a common and widespread species in the delta (Lampsilis siliquoidea) suggest that zebra mussels may be adversely affecting physiological condition of unionids in a portion of the Lake St. Clair delta. Physiological condition and community structure of unionids within the delta may also be influenced by differences in food quantity and quality resulting from the uneven distribution of water flowing from the St. Clair River. The delta likely supports the largest living unionid community in the lower Great Lakes and includes several species that have been listed as Endangered or Threatened in Canada and/or the state of Michigan, making it an important refuge for the conservation of native unionids. Crown Copyright ?? 2009.

  12. Dreissenid mussel research priorities workshop

    USGS Publications Warehouse

    Sytsma, Mark; Phillips, Stephen; Counihan, Timothy D.

    2015-01-01

    Currently, dreissenid mussels have yet to be detected in the northwestern part of the United States and western Canada. Infestation of one of the jurisdictions within the mussel-free Pacific Northwest would likely have significant economic, soci­etal and environmental implications for the entire region. Understanding the biology and environmental tolerances of dreissenid mussels, and effectiveness of various man­agement strategies, is key to prevention.On November 4-5, 2015, the Aquatic Bioinvasion Research and Policy Institute and the Center for Lakes and Reservoirs at Portland State University, the US Geological Survey, and the Pacific States Marine Fisheries Commission, convened a Dreissenid Mussel Research Priorities Workshop funded by the Great Northern Landscape Conservation Cooperative. The purpose of the workshop was to review dreissenid research priorities in the 2010 Quagga-Zebra Mussel Action Plan for Western U.S. Waters, reassess those priorities, incorporate new information and emerging trends, and develop priorities to strategically focus research efforts on zebra and quagga mussels in the Pacific Northwest and ensure that future research is focused on the highest priorities. It is important to note that there is some repetition among dreissenid research priority categories (e.g., prevention, detection, control, monitoring, and biology).Workshop participants with research experience in dreissenid mussel biology and management were identified by a literature review. State and federal agency managers were also invited to the workshop to ensure relevancy and practicality of the work­shop outcomes. A total of 28 experts (see sidebar) in mussel biology, ecology, and management attended the workshop.

  13. Characterization of the multixenobiotic resistance (MXR) mechanism in embryos and larvae of the zebra mussel (Dreissena polymorpha) and studies on its role in tolerance to single and mixture combinations of toxicants.

    PubMed

    Faria, Melissa; Navarro, Ana; Luckenbach, Till; Piña, Benjamin; Barata, Carlos

    2011-01-17

    The study of the cellular mechanisms of tolerance of organisms to pollution is a key issue in aquatic environmental risk assessment. Recent evidence indicates that multixenobiotic resistance (MXR) mechanisms represent a general biological defense of many marine and freshwater organisms against environmental toxicants. In this work, toxicologically relevant xenobiotic efflux transporters were studied in early life stages of zebra mussels (Dreissena polymorpha). Expression of a P-gp1 (ABCB1) transporter gene and its associated efflux activities during development were studied, using qRT-PCR and the fluorescent transporter substrates rhodamine B and calcein-AM combined with specific transporter inhibitors (chemosensitizers). Toxicity bioassays with the model P-gp1 chemotherapeutic drug vinblastine applied singly and in combination with different chemosensitizers were performed to elucidate the tolerance role of the P-gp1 efflux transporter. Results evidenced that the gene expression and associated efflux activities of ABC transporters were low or absent in eggs and increased significantly in 1-3d old trochophora and veliger larvae. Specific inhibitors of Pgp1 and/or MRP transport activities including cyclosporine A, MK571, verapamil and reversin 205 and the musk celestolide resulted in a concentration dependent inhibition of related transport activities in zebra mussel veliger larvae, with IC50 values in the lower micromolar range and similar to those reported for mammals, fish and mussels. Binary mixtures of the tested transporter inhibitors except celestolide with the anticancer drug and P-gp1 substrate vinblastine increased the toxicity of the former compound more than additively. These results indicate that MXR transporter activity is high in early life-stages of the zebra mussel and that may play an important role in the tolerance to environmental contaminants. Copyright © 2010 Elsevier B.V. All rights reserved.

  14. The influence of suspended particles on the acute toxicity of 2-chloro-4-nitro-aniline, cadmium, and pentachlorophenol on the valve movement response of the zebra mussel (Dreissena polymorpha).

    PubMed

    Borcherding, J; Wolf, J

    2001-05-01

    The Dreissena-Monitor is a biological early warning system for the continuous monitoring of river water quality, based on the valve movements of two groups of 42 zebra mussels (Dreissena polymorpha). Laboratory experiments with Cd, PCP, and 2-chloro-4-nitro-aniline were conducted in combination with suspended particles (a mixture of stinging nettle powder, bentonite, and quartz powder). An increase of suspended particles up to a nominal concentration of 540 mg/L within 5 min did not evoke any reactions by the mussels significantly different from normal. The distribution between water and solids was analyzed for Cd and 2-chloro-4-nitroaniline, with the result that the former quickly adsorbed to the particles, whereas the latter did not bind to the particles at all. The behavior of the zebra mussels revealed that the detection of 2-chloro-4-nitro-aniline was not affected by the presence of suspended matter. In the cases of Cd and PCP, D. polymorpha was able to detect these substances when they were particle-associated at least as well or better as when they were dissolved in the water. The results are discussed with respect to the physiology of the organisms and the bioavailability of toxicants, as well as to the consequences these results may have under field conditions.

  15. Temporal and basin-specific population trends of quagga mussels on soft sediment of a multi-basin reservoir

    USGS Publications Warehouse

    Caldwell, Timothy J; Rosen, Michael R.; Chandra, Sudeep; Acharya, Kumud; Caires, Andrea M; Davis, Clinton J.; Thaw, Melissa; Webster, Daniel M.

    2015-01-01

    Invasive quagga (Dreissena bugnesis) and zebra (Dreissena ploymorpha) mussels have rapidly spread throughout North America. Understanding the relationships between environmental variables and quagga mussels during the early stages of invasion will help management strategies and allow researchers to predict patterns of future invasions. Quagga mussels were detected in Lake Mead, NV/AZ in 2007, we monitored early invasion dynamics in 3 basins (Boulder Basin, Las Vegas Bay, Overton Arm) bi-annually from 2008-2011. Mean quagga density increased over time during the first year of monitoring and stabilized for the subsequent two years at the whole-lake scale (8 to 132 individuals·m-2, geometric mean), in Boulder Basin (73 to 875 individuals·m-2), and in Overton Arm(2 to 126 individuals·m-2). In Las Vegas Bay, quagga mussel density was low (9 to 44 individuals·m-2), which was correlated with high sediment metal concentrations and warmer (> 30°C) water temperatures associated with that basin. Carbon content in the sediment increased with depth in Lake Mead and during some sampling periods quagga density was also positively correlated with depth, but more research is required to determine the significance of this interaction. Laboratory growth experiments suggested that food quantity may limit quagga growth in Boulder Basin, indicating an opportunity for population expansion in this basin if primary productivity were to increase, but was not the case in Overton Arm. Overall quagga mussel density in Lake Mead is highly variable and patchy, suggesting that temperature, sediment size, and sediment metal concentrations, and sediment carbon content all contribute to mussel distribution patterns. Quagga mussel density in the soft sediment of Lake Mead expanded during initial colonization, and began to stabilize approximately 3 years after the initial invasion.

  16. Evaluation of freshwater mussel relocation as a conservation and management strategy

    USGS Publications Warehouse

    Cope, W. Gregory; Waller, Diane L.

    1995-01-01

    The relocation of unionacean mussels is commonly used as a conservation and management tool in large rivers and streams. Relocation has been used to recolonize areas where mussel populations have been eliminated by prior pollution events, to remove mussels from construction zones and to re-establish populations of endangered species. More recently, relocation has been used to protect native freshwater mussels from colonization by the exotic zebra mussel Dreissena polymorpha. We conducted a literature review of mussel relocations and evaluated their relative success as a conservation and management strategy. We found that 43% of all relocations were conducted because of construction projects that were forced to comply with the Endangered Species Act 1973 and that only 16% were monitored for five or more consecutive years. Most (43%) relocation projects were conducted from July to September, presumably a period when reproductive stress is relatively low for most species and the metabolic rate is sufficient for reburrowing in the substrate. The mortality of relocated mussels was unreported in 27% of projects; reported mortality varied widely among projects and species and was difficult to assess. The mean mortality of relocated mussels was 49% based on an average recovery rate of 43%. There is little guidance on the methods for relocation or for monitoring the subsequent long-term status of relocated mussels. Based on this evaluation, research is needed to develop criteria for selecting a suitable relocation site and to establish appropriate methods and guidelines for conducting relocation projects.

  17. Bibliography of Dreissena polymorpha (zebra mussels) and Dreissena rostriformis Bugensis (QUAGGA mussels): 1989 to 2011

    USGS Publications Warehouse

    Schloesser, Don W.; Schmuckal, Christine

    2012-01-01

    Dreissenid mussels invaded and colonized waters of the Laurentian Great Lakes during the late 1980s. Their colonization and resulting impact have been characterized as one of the most important ecological changes in freshwater systems in North America. The need for information on dreissenid mussels has grown during the past 2 decades, which has prompted the compilation of this bibliography. Two previous bibliographies of dreissenid mussels indicate average publication rates were 6 publications/year between 1771 and 1964 (1,180 in 194 y) and 30 publications/year between 1964 and 1993 (885 in 30 y). In the current bibliography, the average rate of publication doubled during the past 23 y (1989 to 2011) to 66 publications/year based on a total of 1,502 publications. These rates may be biased by increased numbers of researchers and journals over time but, at a minimum, these rates indicate continued interest and concern by humans about the impact of dreissenid mussels on water availability and the expanding range of dreissenids throughout the world. The current bibliography has a 94% efficiency rate for subject and 100% efficiency for title search criteria when compared with references in published studies of dreissenid mussels in 2011. In addition to publications, we included 206 student theses and 225 chapters in 26 books including 6 books devoted solely to dreissenid mussels. A vast majority of student theses were about dreissenid mussels in North America, especially in the Laurentian Great Lakes. The 6 books devoted to dreissenid mussels contained a variety of chapters that described biology, impact, control, and ecology of dreissenid mussels in both Europe (published in 1992 and 2010) and North America (1993, 1994, 1997, and 2000). In addition, there is a 7th book devoted solely to dreissenid mussels that is near completion.

  18. Contrasting results from molecular and pedigree-based population diversity measures in captive zebra highlight challenges facing genetic management of zoo populations.

    PubMed

    Ito, Hideyuki; Ogden, Rob; Langenhorst, Tanya; Inoue-Murayama, Miho

    2017-01-01

    Zoo conservation breeding programs manage the retention of population genetic diversity through analysis of pedigree records. The range of demographic and genetic indices determined through pedigree analysis programs allows the conservation of diversity to be monitored relative to the particular founder population for a species. Such approaches are based on a number of well-documented founder assumptions, however without knowledge of actual molecular genetic diversity there is a risk that pedigree-based measures will be misinterpreted and population genetic diversity misunderstood. We examined the genetic diversity of the captive populations of Grevy's zebra, Hartmann's mountain zebra and plains zebra in Japan and the United Kingdom through analysis of mitochondrial DNA sequences. Very low nucleotide variability was observed in Grevy's zebra. The results were evaluated with respect to current and historic diversity in the wild, and indicate that low genetic diversity in the captive population is likely a result of low founder diversity, which in turn suggests relatively low wild genetic diversity prior to recent population declines. Comparison of molecular genetic diversity measures with analogous diversity indices generated from the studbook data for Grevy's zebra and Hartmann's mountain zebra show contrasting patterns, with Grevy's zebra displaying markedly less molecular diversity than mountain zebra, despite studbook analysis indicating that the Grevy's zebra population has substantially more founders, greater effective population size, lower mean kinship, and has suffered less loss of gene diversity. These findings emphasize the need to validate theoretical estimates of genetic diversity in captive breeding programs with empirical molecular genetic data. Zoo Biol. 36:87-94, 2017. © 2016 Wiley Periodicals, Inc. © 2016 Wiley Periodicals, Inc.

  19. Activation of AMP-activated protein kinase in response to temperature elevation shows seasonal variation in the zebra mussel, Dreissena polymorpha.

    PubMed

    Jost, Jennifer A; Keshwani, Sarah S; Abou-Hanna, Jacob J

    2015-04-01

    Global climate change is affecting ectothermic species, and a variety of studies are needed on thermal tolerances, especially from cellular and physiological perspectives. This study utilized AMP-activated protein kinase (AMPK), a key regulator of cellular energy levels, to examine the effects of high water temperatures on zebra mussel (Dreissena polymorpha) physiology. During heating, AMPK activity increased as water temperature increased to a point, and maximum AMPK activity was detected at high, but sublethal, water temperatures. This pattern varied with season, suggesting that cellular mechanisms of seasonal thermal acclimatization affect basic metabolic processes during sublethal heat stress. There was a greater seasonal variation in the water temperature at which maximum AMPK activity was measured than in lethal water temperature. Furthermore, baseline AMPK activity varied significantly across seasons, most likely reflecting altered metabolic states during times of growth and reproduction. In addition, when summer-collected mussels were lab-acclimated to winter and spring water temperatures, patterns of heat stress mirrored those of field-collected animals. These data suggest that water temperature is the main driver of the seasonal variation in physiology. This study concluded that AMPK activity, which reflects changes in energy supply and demand during heat stress, can serve as a sensitive and early indicator of temperature stress in mussels. Copyright © 2014 Elsevier Inc. All rights reserved.

  20. Pathogens and diseases of freshwater mussels in the United States: Studies on bacterial transmission and depuration

    USGS Publications Warehouse

    Starliper, Clifford E.; Cipriano, R.C.; Bruckner, A.W.; Shchelkunov, I.S.

    2011-01-01

    Unionid mussels are recognized as important contributors to healthy aquatic ecosystems, as well as bioindicators of environmental perturbations. Because they are sedentary, filter feeding animals and require hosts (i.e., fishes) to transform embryonic glochidia, mussels are susceptible to direct adverse environmental parameters, and indirect parameters that restrict the timely presence of the host(s). Their numbers have declined in recent decades to a point that this fauna is regarded as one of the most imperiled in North America. The most significant threat to populations of native unionids in recent years has been the introduction and spread of zebra mussels Dreissena polymorpha. Many federal and state agencies, and private interests are now engaged in mussel conservation efforts, including collecting selected imperiled species from impacted rivers and lakes and propagating them at refuges for future population augmentations. One essential consideration with mussel propagation and their intensive culture at refugia is the prevention of pathogen introductions and control of diseases. Currently, there are few reports of etiological agents causing diseases among freshwater mussels; however, because of increased observations of mussel die-offs in conjunction with transfers of live animals between natural waters and refugia, disease problems can be anticipated to emerge. This review summarizes research to develop bacterial isolation techniques, study pathogen transmission between fish and mussels, identify causes of seasonal mussel die-offs, and develop non-destructive methods for pathogen detection. These efforts were done to develop disease preventative techniques for use by resource managers to avoid potential large-scale disease problems in restoration and population augmentation efforts among imperiled populations.

  1. Changes in the dreissenid community in the lower Great Lakes with emphasis on southern Lake Ontario

    USGS Publications Warehouse

    Mills, Edward L.; Chrisman, Jana R.; Baldwin, Brad; Owens, Randall W.; O'Gorman, Robert; Howell, Todd; Roseman, Edward F.; Raths, Melinda K.

    1999-01-01

    A field study was conducted in the lower Great Lakes to assess changes in spatial distribution and population structure of dreissenid mussel populations. More specifically, the westward range expansion of quagga mussel into western Lake Erie and toward Lake Huron was investigated and the shell size, density, and biomass of zebra and quagga mussel with depth in southern Lake Ontario in 1992 and 1995 were compared. In Lake Erie, quagga mussel dominated the dreissenid community in the eastern basin and zebra mussel dominated in the western basin. In southern Lake Ontario, an east to west gradient was observed with the quagga mussel dominant at western sites and zebra mussel dominant at eastern locations. Mean shell size of quagga mussel was generally larger than that of zebra mussel except in western Lake Erie and one site in eastern Lake Erie. Although mean shell size and our index of numbers and biomass of both dreissenid species increased sharply in southern Lake Ontario between 1992 and 1995, the increase in density and biomass was much greater for quagga mussels over the 3-year period. In 1995, zebra mussels were most abundant at 15 to 25 m whereas the highest numbers and biomass of quagga mussel were at 35 to 45 m. The quagga mussel is now the most abundant dreissenid in areas of southern Lake Ontario where the zebra mussel was once the most abundant dreissenid; this trend parallels that observed for dreissenid populations in the Dneiper River basin in the Ukraine.

  2. Evaluation of relocation of unionid mussels into artificial ponds

    USGS Publications Warehouse

    Newton, T.J.; Monroe, E.M.; Kenyon, R.; Gutreuter, S.; Welke, K.I.; Thiel, P.A.

    2001-01-01

    Relocation of unionid mussels into refuges (e.g., hatchery ponds) has been suggested as a management tool to protect these animals from the threat of zebra mussel (Dreissena polymorpha) invasion. To evaluate the efficacy of relocation, we experimentally relocated 768 mussels, representing 5 species (Leptodea fragilis, Obliquaria reflexa, Fusconaia flava, Amblema plicata, and Quadrula quadrula) into an earthen pond at a National Fish Hatchery or back into the river. In both locations, mussels were placed into 1 of 4 treatments (mesh bags, corrals, and buried or suspended substrate-filled trays). Mussels were examined annually for survival, growth (shell length and wet mass), and physiological condition (glycogen concentration in foot and mantle and tissue condition index) for 36 mo in the pond or 40 mo in the river. We observed significant differences in mortality rates between locations (mortality was 4 times greater in the pond than in the river), among treatments (lowest mortality in the suspended trays), and among species (lower mortality in the amblemines than lamp-silines). Overall survival in both locations averaged 80% the 1st year; survival in the pond decreased dramatically after that. Although length and weight varied between locations and over time, these changes were small, suggesting that their utility as short-term measures of well being in long-lived unionids is questionable. Mussels relocated to the pond were in poor physiological condition relative to those in the river, but the magnitude of these differences was small compared to the inherent variability in physiological condition of reference mussels. These data suggest that relocation of unionids into artificial ponds is a high-risk conservation strategy; alternatives such as introduction of infected host fish, identification of mussel beds at greatest risk from zebra mussels, and a critical, large-scale assessment of the factors contributing to their decline should be explored.

  3. Validated methodology for quantifying infestation levels of dreissenid mussels in environmental DNA (eDNA) samples.

    PubMed

    Peñarrubia, Luis; Alcaraz, Carles; Vaate, Abraham Bij de; Sanz, Nuria; Pla, Carles; Vidal, Oriol; Viñas, Jordi

    2016-12-14

    The zebra mussel (Dreissena polymorpha Pallas, 1771) and the quagga mussel (D. rostriformis Deshayes, 1838) are successful invasive bivalves with substantial ecological and economic impacts in freshwater systems once they become established. Since their eradication is extremely difficult, their detection at an early stage is crucial to prevent spread. In this study, we optimized and validated a qPCR detection method based on the histone H2B gene to quantify combined infestation levels of zebra and quagga mussels in environmental DNA samples. Our results show specific dreissenid DNA present in filtered water samples for which microscopic diagnostic identification for larvae failed. Monitoring a large number of locations for invasive dreissenid species based on a highly specific environmental DNA qPCR assay may prove to be an essential tool for management and control plans focused on prevention of establishment of dreissenid mussels in new locations.

  4. Validated methodology for quantifying infestation levels of dreissenid mussels in environmental DNA (eDNA) samples

    PubMed Central

    Peñarrubia, Luis; Alcaraz, Carles; Vaate, Abraham bij de; Sanz, Nuria; Pla, Carles; Vidal, Oriol; Viñas, Jordi

    2016-01-01

    The zebra mussel (Dreissena polymorpha Pallas, 1771) and the quagga mussel (D. rostriformis Deshayes, 1838) are successful invasive bivalves with substantial ecological and economic impacts in freshwater systems once they become established. Since their eradication is extremely difficult, their detection at an early stage is crucial to prevent spread. In this study, we optimized and validated a qPCR detection method based on the histone H2B gene to quantify combined infestation levels of zebra and quagga mussels in environmental DNA samples. Our results show specific dreissenid DNA present in filtered water samples for which microscopic diagnostic identification for larvae failed. Monitoring a large number of locations for invasive dreissenid species based on a highly specific environmental DNA qPCR assay may prove to be an essential tool for management and control plans focused on prevention of establishment of dreissenid mussels in new locations. PMID:27966602

  5. Zebra mussel effects on benthic invertebrates: physical or biotic?

    USGS Publications Warehouse

    Botts, P. Silver; Patterson, Benjamin A.; Schloesser, Don W.

    1996-01-01

    In soft sediments, Dreissena spp. create firm substrate in the form of aggregates of living mussels (druses) that roll free on the sediments. Druses provide physical structure which increases habitat heterogeneity, and the mussels increase benthic organic matter through the production of pseudofeces and feces. Descriptive and experimental studies were used to determine: 1) whether the density of benthic invertebrates in soft sediments increased in the presence of druses, and 2) whether the invertebrate assemblage responded to the physical structure provided by a druse or to some biotic effect associated with the presence of living mussels. In core samples collected biweekly during summer in Presque Isle Bay, Erie, Pennsylvania, amphipods, chironomids, oligochaetes, turbellarians, and hydrozoans were significantly more abundant in sand with druses than in bare sand. When mesh bags containing either a living druse, non-living druse, or no druse were incubated in the bay for 33 d, we found that chironomids were significantly more abundant in treatments with living druses than with non-living druses, and in treatments with non-living druses than with no druse; turbellarians, amphipods, and hydrozoans were significantly more abundant in treatments with living or non-living druses than with no druse; oligochaetes showed no significant differences among treatments. This study demonstrates that most taxa of benthic invertebrates in soft substrate respond specifically to the physical structure associated with aggregates of mussel shells, but further study is needed to examine chironomid responses to some biotic effect dependent on the presence of living mussels.

  6. Shell-free biomass and population dynamics of dreissenids in offshore Lake Michigan, 2001-2003

    USGS Publications Warehouse

    French, J. R. P.; Adams, J.V.; Craig, J.; Stickel, R.G.; Nichols, S.J.; Fleischer, G.W.

    2007-01-01

    The USGS-Great Lakes Science Center has collected dreissenid mussels annually from Lake Michigan since zebra mussels (Dreissena polymorpha) became a significant portion of the bottom-trawl catch in 1999. For this study, we investigated dreissenid distribution, body mass, and recruitment at different depths in Lake Michigan during 2001-2003. The highest densities of dreissenid biomass were observed from depths of 27 to 46 m. The biomass of quagga mussels (Dreissena bugensis) increased exponentially during 2001-2003, while that of zebra mussels did not change significantly. Body mass (standardized for a given shell length) of both species was lowest from depths of 27 to 37m, highest from 55 to 64 m, and declined linearly at deeper depths during 2001-2003. Recruitment in 2003, as characterized by the proportion of mussels < 11 mm in the catch, varied with depth and lake region. For quagga mussels, recruitment declined linearly with depth, and was highest in northern Lake Michigan. For zebra mussels, recruitment generally declined non-linearly with depth, although the pattern was different for north, mid, and southern Lake Michigan. Our analyses suggest that quagga mussels could overtake zebra mussels and become the most abundant mollusk in terms of biomass in Lake Michigan.

  7. Zebra Finch Song Phonology and Syntactical Structure across Populations and Continents-A Computational Comparison.

    PubMed

    Lachlan, Robert F; van Heijningen, Caroline A A; Ter Haar, Sita M; Ten Cate, Carel

    2016-01-01

    Learned bird songs are often characterized by a high degree of variation between individuals and sometimes between populations, while at the same time maintaining species specificity. The evolution of such songs depends on the balance between plasticity and constraints. Captive populations provide an opportunity to examine signal variation and differentiation in detail, so we analyzed adult male zebra finch (Taeniopygia guttata) songs recorded from 13 populations across the world, including one sample of songs from wild-caught males in their native Australia. Cluster analysis suggested some, albeit limited, evidence that zebra finch song units belonged to universal, species-wide categories, linked to restrictions in vocal production and non-song parts of the vocal repertoire. Across populations, songs also showed some syntactical structure, although any song unit could be placed anywhere within the song. On the other hand, there was a statistically significant differentiation between populations, but the effect size was very small, and its communicative significance dubious. Our results suggest that variation in zebra finch songs within a population is largely determined by species-wide constraints rather than population-specific features. Although captive zebra finch populations have been sufficiently isolated to allow them to genetically diverge, there does not appear to have been any divergence in the genetically determined constraints that underlie song learning. Perhaps more surprising is the lack of locally diverged cultural traditions. Zebra finches serve as an example of a system where frequent learning errors may rapidly create within-population diversity, within broad phonological and syntactical constraints, and prevent the formation of long-term cultural traditions that allow populations to diverge.

  8. Developmental plasticity of shell morphology of quagga mussels from shallow and deep-water habitats of the Great Lakes

    Treesearch

    Suzanne Peyer; John C. Hermanson; Carol Eunmi Lee

    2010-01-01

    The invasive zebra mussel (Dreissena polymorpha) has quickly colonized shallow-water habitats in the North American Great Lakes since the 1980s but the quagga mussel (Dreissena bugensis) is becoming dominant in both shallow and deep-water habitats. While quagga mussel shell morphology differs between shallow and deep habitats, functional causes and consequences of such...

  9. Estimation of mussel population response to hydrologic alteration in a southeastern U.S. stream

    USGS Publications Warehouse

    Peterson, J.T.; Wisniewski, J.M.; Shea, C.P.; Rhett, Jackson C.

    2011-01-01

    The southeastern United States has experienced severe, recurrent drought, rapid human population growth, and increasing agricultural irrigation during recent decades, resulting in greater demand for the water resources. During the same time period, freshwater mussels (Unioniformes) in the region have experienced substantial population declines. Consequently, there is growing interest in determining how mussel population declines are related to activities associated with water resource development. Determining the causes of mussel population declines requires, in part, an understanding of the factors influencing mussel population dynamics. We developed Pradel reverse-time, tag-recapture models to estimate survival, recruitment, and population growth rates for three federally endangered mussel species in the Apalachicola- Chattahoochee-Flint River Basin, Georgia. The models were parameterized using mussel tag-recapture data collected over five consecutive years from Sawhatchee Creek, located in southwestern Georgia. Model estimates indicated that mussel survival was strongly and negatively related to high flows during the summer, whereas recruitment was strongly and positively related to flows during the spring and summer. Using these models, we simulated mussel population dynamics under historic (1940-1969) and current (1980-2008) flow regimes and under increasing levels of water use to evaluate the relative effectiveness of alternative minimum flow regulations. The simulations indicated that the probability of simulated mussel population extinction was at least 8 times greater under current hydrologic regimes. In addition, simulations of mussel extinction under varying levels of water use indicated that the relative risk of extinction increased with increased water use across a range of minimum flow regulations. The simulation results also indicated that our estimates of the effects of water use on mussel extinction were influenced by the assumptions about the

  10. Differential sensitivity to cadmium of immunomarkers measured in hemocyte subpopulations of zebra mussel Dreissena polymorpha.

    PubMed

    Evariste, Lauris; Rioult, Damien; Brousseau, Pauline; Geffard, Alain; David, Elise; Auffret, Michel; Fournier, Michel; Betoulle, Stéphane

    2017-03-01

    Increasing discharge of industrial wastes into the environment results in pollution transfer towards hydrosystems. These activities release heavy metals such as cadmium, known as persistent pollutant that is accumulated by molluscs and exercise immunotoxicological effects. Among molluscs, the zebra mussel, Dreissena polymorpha constitutes a suitable support for freshwater ecotoxicological studies. In molluscs, homeostasis maintain is ensured in part by hemocytes that are composed of several cell populations involved in multiple physiological processes such as cell-mediated immune response or metal metabolism. Thus, hemocytes constitute a target of concern to study adverse effects of heavy metals. The objectives of this work were to determine whether immune-related endpoints assessed were of different sensitivity to cadmium and whether hemocyte functionalities were differentially affected depending on hemocyte subpopulation considered. Hemocytes were exposed ex vivo to concentrations of cadmium ranging from 10 -6 M to 10 -3 M for 21h prior flow cytometric analysis of cellular markers. Measured parameters (viability, phagocytosis, oxidative activity, lysosomal content) decreased in a dose-dependent manner with sensitivity differences depending on endpoint and cell type considered. Our results indicated that phagocytosis related endpoints were the most sensitive studied mechanisms to cadmium compared to other markers with EC 50 of 3.71±0.53×10 -4 M for phagocytic activity and 2.79±0.19×10 -4 M considering mean number of beads per phagocytic cell. Lysosomal content of granulocytes was less affected compared to other cell types, indicating lower sensitivity to cadmium. This suggests that granulocyte population is greatly involved in metal metabolism. Mitochondrial activity was reduced only in blast-like hemocytes that are considered to be cell precursors. Impairment of these cell functionalities may potentially compromise functions ensured by differentiated cells

  11. ANALYSIS OF MATERIALS IN AN EXPERIMENTAL TESTING PIPE SYSTEM FOR AN INHIBITOR OF MUSSEL KILL

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Daniel P. Molloy

    2003-06-04

    A comprehensive series of 16 laboratory experiments demonstrated that the presence of vinyl tubing within a recirculating pipe system was responsible for lowering zebra mussel kill following treatment with the bacterium Pseudomonas fluorescens. All vinyl tubing was replaced in all testing units with silicone tubing, and high mussel kill (>95%) was then obtained.

  12. Cumulative effects of ibuprofen and air emersion in zebra mussels Dreissena polymorpha.

    PubMed

    André, C; Gagné, F

    2017-10-01

    Municipal effluents are major source of pharmaceutical products in the environment. The purpose of this study was to examine the toxicity of a largely used drug, ibuprofen (Ibu), in Dresseina polymorpha mussels and its impact on air survival time. The mussels were exposed to increasing concentration of Ibu (0, 1, 10 and 100μg/L) for 96 at 15°C and a sub-group of mussels was maintain in air for another 96h. Post-exposure mussels (Ibu and Ibu+Air) were analyzed for weight loss, total triglycerides, neutral lipids, lipid peroxidation (LPO), arachidonate-dependent cyclooxygenase (COX) and glutathione S-transferase activity. Lipid extracts of mussel tissues were also analyzed by 1 H-nuclear resonance spectroscopy. The data revealed that mussels exposed to Ibu had increased signs of lipid oxidation, neutral lipids and decreased triglycerides, LPO and GST activity. COX activity was significantly reduced by Ibu in keeping with mode of action of the drug. Following exposure to air, increased weight loss, neutral lipids (lipid degradation), were observed in mussels exposed to Ibu but no changes in COX activity were observed. Air stress limited the decrease in triglycerides and the increase in GST in mussels exposed to 100μg/L Ibu indicating decreased anti-oxidant response/phase II biotransformation and limited lipid metabolism. In conclusion, exposure to Ibu has some anti-inflammatory effects to mussels based on COX activity but resulted in increased oxidative damage and lipid catabolism. Exposure to air stress could enhance some of these responses and contribute to decreased resistance to air exposures. Crown Copyright © 2017. Published by Elsevier B.V. All rights reserved.

  13. The Quagga mussel invades the Lake Superior basin - journal article

    EPA Science Inventory

    Prior studies recognized the presence of a single dreissenid species in Lake Superior--the zebra mussel Dreissena polymorpha. However, taxonomic keys based on traditional shell morphology are not always able to differentiate dreissenid species with confidence. We thus employed ge...

  14. Application of adaptive cluster sampling to low-density populations of freshwater mussels

    USGS Publications Warehouse

    Smith, D.R.; Villella, R.F.; Lemarie, D.P.

    2003-01-01

    Freshwater mussels appear to be promising candidates for adaptive cluster sampling because they are benthic macroinvertebrates that cluster spatially and are frequently found at low densities. We applied adaptive cluster sampling to estimate density of freshwater mussels at 24 sites along the Cacapon River, WV, where a preliminary timed search indicated that mussels were present at low density. Adaptive cluster sampling increased yield of individual mussels and detection of uncommon species; however, it did not improve precision of density estimates. Because finding uncommon species, collecting individuals of those species, and estimating their densities are important conservation activities, additional research is warranted on application of adaptive cluster sampling to freshwater mussels. However, at this time we do not recommend routine application of adaptive cluster sampling to freshwater mussel populations. The ultimate, and currently unanswered, question is how to tell when adaptive cluster sampling should be used, i.e., when is a population sufficiently rare and clustered for adaptive cluster sampling to be efficient and practical? A cost-effective procedure needs to be developed to identify biological populations for which adaptive cluster sampling is appropriate.

  15. IMPACT OF FIVE TREATMENT FACTORS ON MUSSEL MORTALITY

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Daniel P. Molloy

    2003-12-08

    Under this USDOE-NETL contract, the bacterium Pseudomonas fluorescens is being developed as a biocontrol agent for zebra mussels. The specific purpose of the contract is to identify factors that affect mussel kill. Test results reported herein indicate that mussel kill should not be affected by: (1) air bubbles being carried by currents through power plant pipes; (2) pipe orientation (e.g., vertical or horizontal); (3) whether the bacterial cell concentration during a treatment is constant or slightly varying; (4) whether a treatment is between 3 hr and 12 hr in duration, given that the total quantity of bacteria being applied tomore » the pipe is a constant; and (5) whether the water temperature is between 13 C and 23 C.« less

  16. Concentrations of 17 elements in the zebra mussel (Dreissena polymorpha), in different tissues of perch (Perca fluviatilis), and in perch intestinal parasites (Acanthocephalus lucii) from the subalpine lake Mondsee, Austria

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Sures, B.; Steiner, W.; Rydlo, M.

    1999-11-01

    Concentrations of the elements Al, Ag, Ba, ca, Cd, Co, Cr, cu, Fe, Ga, Mg, Mn, Ni, Pb, Sr, Tl, and Zn were analyzed by inductively coupled plasma mass spectrometry in the acanthocephalan Acanthocephalus lucii (Mueller); in its host, Perca fluviatilis (L.), and in the soft tissue of the zebra mussel, Dreissena polymorpha (Pallas). All animals were collected from the same sampling site in a subalpine lake, Mondsee, in Austria. Most of the elements were found at significantly higher concentrations in the acanthocephalan than in different tissues (muscle, liver, and intestinal wall) of its perch host. Only Co was concentratedmore » in the liver of perch to a level that was significantly higher than that found in the parasite. Most of the analyzed elements were also present at significantly higher concentrations in A. lucii than in D. polymorpha. Barium and Cr were the only elements recorded at higher concentrations in the mussel compared with the acanthocephalan. Thus, when comparing the accumulation of elements, the acanthocephalans appear to be even more suitable than the zebra mussels in terms of their use in the detection of metal contamination within aquatic biotopes. Spearman correlation analysis revealed that the concentrations of several elements within the parasites decreased with increasing infrapopulation. Furthermore, the levels of some elements in the perch liver were negatively correlated with the weight of A. lucii in the intestine. Thus, it emerged that not only is there competition for elements between acanthocephalans inside the gut but there is also competition for these elements between the host and the parasites. The elevated element concentrations demonstrated here in the parasitic worm A. lucii provide support for further investigations of these common helminthes and of their accumulation properties.« less

  17. Divergent induced responses to an invasive predator in marine mussel populations.

    PubMed

    Freeman, Aaren S; Byers, James E

    2006-08-11

    Invasive species may precipitate evolutionary change in invaded communities. In southern New England (USA) the invasive Asian shore crab, Hemigrapsus sanguineus, preys on mussels (Mytlius edulis), but the crab has not yet invaded northern New England. We show that southern New England mussels express inducible shell thickening when exposed to waterborne cues from Hemigrapsus, whereas naïve northern mussel populations do not respond. Yet, both populations thicken their shells in response to a long-established crab, Carcinus maenas. Our findings are consistent with the rapid evolution of an inducible morphological response to Hemigrapsus within 15 years of its introduction.

  18. Altered trophic pathway and parasitism in a native predator (Lepomis gibbosus) feeding on introduced prey (Dreissena polymorpha).

    PubMed

    Locke, Sean A; Bulté, Grégory; Marcogliese, David J; Forbes, Mark R

    2014-05-01

    Populations of invasive species tend to have fewer parasites in their introduced ranges than in their native ranges and are also thought to have fewer parasites than native prey. This 'release' from parasites has unstudied implications for native predators feeding on exotic prey. In particular, shifts from native to exotic prey should reduce levels of trophically transmitted parasites. We tested this hypothesis in native populations of pumpkinseed sunfish (Lepomis gibbosus) in Lake Opinicon, where fish stomach contents were studied intensively in the 1970s, prior to the appearance of exotic zebra mussels (Dreissena polymorpha) in the mid-1990s. Zebra mussels were common in stomachs of present-day pumpkinseeds, and stable isotopes of carbon and nitrogen confirmed their importance in long-term diets. Because historical parasite data were not available in Lake Opinicon, we also surveyed stomach contents and parasites in pumpkinseed in both Lake Opinicon and an ecologically similar, neighboring lake where zebra mussels were absent. Stomach contents of pumpkinseed in the companion lake did not differ from those of pre-invasion fish from Lake Opinicon. The companion lake, therefore, served as a surrogate "pre-invasion" reference to assess effects of zebra mussel consumption on parasites in pumpkinseed. Trophically transmitted parasites were less species-rich and abundant in Lake Opinicon, where fish fed on zebra mussels, although factors other than zebra mussel consumption may contribute to these differences. Predation on zebra mussels has clearly contributed to a novel trophic coupling between littoral and pelagic food webs in Lake Opinicon.

  19. Hydrology and grazing jointly control a large-river food web.

    PubMed

    Strayer, David L; Pace, Michael L; Caraco, Nina F; Cole, Jonathan J; Findlay, Stuart E G

    2008-01-01

    Inputs of fresh water and grazing both can control aquatic food webs, but little is known about the relative strengths of and interactions between these controls. We use long-term data on the food web of the freshwater Hudson River estuary to investigate the importance of, and interactions between, inputs of fresh water and grazing by the invasive zebra mussel (Dreissena polymorpha). Both freshwater inputs and zebra mussel grazing have strong, pervasive effects on the Hudson River food web. High flow tended to reduce population size in most parts of the food web. High grazing also reduced populations in the planktonic food web, but increased populations in the littoral food web, probably as a result of increases in water clarity. The influences of flow and zebra mussel grazing were roughly equal (i.e., within a factor of 2) for many variables over the period of our study. Zebra mussel grazing made phytoplankton less sensitive to freshwater inputs, but water clarity and the littoral food web more sensitive to freshwater inputs, showing that interactions between these two controlling factors can be strong and varied.

  20. Polymethylene-interrupted fatty acids: Biomarkers for native and exotic mussels in the Laurentian Great Lakes

    USGS Publications Warehouse

    Mezek, Tadej; Sverko, Ed; Ruddy, Martina D.; Zaruk, Donna; Capretta, Alfredo; Hebert, Craig E.; Fisk, Aaron T.; McGoldrick, Daryl J.; Newton, Teresa J.; Sutton, Trent M.; Koops, Marten A.; Muir, Andrew M.; Johnson, Timothy B.; Ebener, Mark P.; Arts, Michael T.

    2011-01-01

    Freshwater organisms synthesize a wide variety of fatty acids (FAs); however, the ability to synthesize and/or subsequently modify a particular FA is not universal, making it possible to use certain FAs as biomarkers. Herein we document the occurrence of unusual FAs (polymethylene-interrupted fatty acids; PMI-FAs) in select freshwater organisms in the Laurentian Great Lakes. We did not detect PMI-FAs in: (a) natural seston from Lake Erie and Hamilton Harbor (Lake Ontario), (b) various species of laboratory-cultured algae including a green alga (Scenedesmus obliquus), two cyanobacteria (Aphanizomenon flos-aquae and Synechococystis sp.), two diatoms (Asterionella formosa, Diatoma elongatum) and a chrysophyte (Dinobryon cylindricum) or, (c) zooplankton (Daphnia spp., calanoid or cyclopoid copepods) from Lake Ontario, suggesting that PMI-FAs are not substantively incorporated into consumers at the phytoplankton–zooplankton interface. However, these unusual FAs comprised 4-6% of total fatty acids (on a dry tissue weight basis) of native fat mucket (Lampsilis siliquoidea) and plain pocketbook (L. cardium) mussels and in invasive zebra (Dreissena polymorpha) and quagga (D. bugensis) mussels. We were able to clearly partition Great Lakes' mussels into three separate groups (zebra, quagga, and native mussels) based solely on their PMI-FA profiles. We also provide evidence for the trophic transfer of PMI-FAs from mussels to various fishes in Lakes Ontario and Michigan, further underlining the potential usefulness of PMI-FAs for tracking the dietary contribution of mollusks in food web and contaminant-fate studies.

  1. Dreissenid mussels from the Great Lakes contain elevated thiaminase activity

    USGS Publications Warehouse

    Tillitt, D.E.; Riley, S.C.; Evans, A.N.; Nichols, S.J.; Zajicek, J.L.; Rinchard, J.; Richter, C.A.; Krueger, C.C.

    2009-01-01

    We examined thiaminase activity in dreissenid mussels collected at different depths and seasons, and from various locations in Lakes Michigan, Ontario, and Huron. Here we present evidence that two dreissenid mussel species (Dreissena bugensis and D. polymorpha) contain thiaminase activity that is 5-100 fold greater than observed in Great Lakes fishes. Thiaminase activity in zebra mussels ranged from 10,600 to 47,900??pmol g- 1??min- 1 and activities in quagga mussels ranged from 19,500 to 223,800??pmol g- 1??min- 1. Activity in the mussels was greatest in spring, less in summer, and least in fall. Additionally, we observed greater thiaminase activity in dreissenid mussels collected at shallow depths compared to mussels collected at deeper depths. Dreissenids constitute a significant and previously unknown pool of thiaminase in the Great Lakes food web compared to other known sources of this thiamine (vitamin B1)-degrading enzyme. Thiaminase in forage fish of the Great Lakes has been causally linked to thiamine deficiency in salmonines. We currently do not know whether linkages exist between thiaminase activities observed in dreissenids and the thiaminase activities in higher trophic levels of the Great Lakes food web. However, the extreme thiaminase activities observed in dreissenids from the Great Lakes may represent a serious unanticipated negative effect of these exotic species on Great Lakes ecosystems.

  2. Molecular markers for genetic diversity, gene flow and genetic population structure of freshwater mussel species.

    PubMed

    Choupina, A B; Martins, I M

    2014-08-01

    Freshwater mussel species are in global decline. Anthropogenic changes of river channels and the decrease of autochthonous fish population, the natural hosts of mussels larval stages (glochidia), are the main causes. Therefore, the conservation of mussel species depends not only on habitat conservation, but also on the availability of the fish host. In Portugal, information concerning most of the mussel species is remarkably scarce. One of the most known species, Unio pictorum is also in decline however, in the basins of the rivers Tua and Sabor (Northeast of Portugal), there is some indication of relatively large populations. The aforementioned rivers can be extremely important for this species conservation not only in Portugal, but also in the remaining Iberian Peninsula. Thus, it is important to obtain data concerning Unio pictorum bioecology (distribution, habitat requirements, population structure, genetic variability, reproductive cycle and recruitment rates), as well as the genetic variability and structure of the population. Concomitantly, information concerning fish population structure, the importance of the different fish species as "glochidia" hosts and their appropriate density to allow effective mussel recruitment, will also be assessed. The achieved data is crucial to obtain information to develop effective management measures in order to promote the conservation of this bivalve species, the conservation of autochthonous fish populations, and consequently the integrity of the river habitats.

  3. Efficacy of Pseudomonas fluorescens strain CL145A spray dried powder for controlling zebra mussels adhering to native unionid mussels within field enclosures

    USGS Publications Warehouse

    Luoma, James A.; Weber, Kerry L.; Severson, Todd J.; Mayer, Denise A.

    2015-01-01

    Group 1 mussel survival did not differ between treatment groups (p > 0.05); however, a difference was detected (p < 0.01) in the survival of Group 2 mussels. The survival of Group 2 mussels did not differ (p > 0.23) between control and treated groups. A difference in Group 2 mussel survival was detected (p = 0.03; odds ratio [OR] = 0.290) between the 50- and 100-mg/L treatment groups (that is, the survival was highest in the 50-mg/L treatment group and lowest in the 100-mg/L treatment group), however, the biological significance of the difference is indeterminate.

  4. Extirpation of freshwater mussels (Bivalvia: Unionidae) following the invasion of dreissenid mussels in an interconnecting river of the Laurentian Great Lakes

    USGS Publications Warehouse

    Schloesser, Don W.; Metcalfe-Smith, Janice L.; Kovalak, William P.; Longton, Gary D.; Smithee, Rick D.

    2006-01-01

    Previous (1992-1994) surveys for native freshwater mussels (Unionidae) along main channels of the Detroit River showed that unionids had been extirpated from all but four sites in the upper reaches of the river due to impacts of dreissenid mussels (Dreissena polymorpha and D. bugensis). These four sites were surveyed again in 1998 using the same sampling method (timed-random searches) to determine if they may serve as ''refugia'' where unionids and dreissenids co-exist. Two additional sites were sampled using additional methods (excavated-quadrat and line-transect searches) for comparison with unpublished data collected in 1987 and 1990. A total of four individuals of four species (Actinonaias ligamentina, Cyclonaias tuberculata, Lasmigona complanata and Pleurobema sintoxia) were found by timed-random searches at four sites in 1998 compared to 720 individuals of 24 species in 1992 and 39 individuals of 13 species in 1994. Excavated-quadrat and line-transect searches at the two additional sites yielded only one live specimen of Ptychobranchus fasciolaris compared to 288 individuals of 18 species in 1987 and 1990. Results of this study suggest that remaining densities of unionids in channels of the Detroit River are too low to support viable reproducing populations of any species. Therefore, we conclude that unionids have been extirpated from main channels of the Detroit River due to dreissenid infestation. As the Detroit River was one of the first water bodies in North America to be invaded by dreissenids, it is likely that unionids will also be extirpated from many other rivers and lakes across eastern North America over the next few decades. Resource agencies should be encouraged to implement active management programs to protect remaining unionid populations from zebra mussels.

  5. Integrated use of biomarkers and bioaccumulation data in Zebra mussel (Dreissena polymorpha) for site-specific quality assessment.

    PubMed

    Binelli, A; Ricciardi, F; Riva, C; Provini, A

    2006-01-01

    One of the useful biological tools for environmental management is the measurement of biomarkers whose changes are related to the exposure to chemicals or environmental stress. Since these responses might vary with different contaminants or depending on the pollutant concentration reached in the organism, the support of bioaccumulation data is needed to prevent false conclusions. In this study, several persistent organic pollutants -- 23 polychlorinated biphenyl (PCB) congeners, 11 polycyclic aromatic hydrocarbons (PAHs), six dichlorodiphenyltricholroethane (DDT) relatives, hexachlorobenzene (HCB), chlorpyrifos and its oxidized metabolite -- and some herbicides (lindane and the isomers alpha, beta, delta; terbutilazine; alachlor; metolachlor) were measured in the soft tissues of the freshwater mollusc Zebra mussel (Dreissena polymorpha) from 25 sampling sites in the Italian portions of the sub-alpine great lakes along with the measure of ethoxyresorufin dealkylation (EROD) and acetylcholinesterase (AChE) activity. The linkage between bioaccumulation and biomarker data allowed us to create site-specific environmental quality indexes towards man-made chemicals. This classification highlighted three different degrees of xenobiotic contamination of the Italian sub-alpine great lakes: a high water quality in Lake Lugano with negligible pollutant levels and no effects on enzyme activities, an homogeneous poor quality for Lakes Garda, Iseo and Como, and the presence of some xenobiotic point-sources in Lake Maggiore, whose ecological status could be jeopardized, also due to the heavy DDT contamination revealed since 1996.

  6. Freshwater mussels in an urban watershed: Impacts of anthropogenic inputs and habitat alterations on populations.

    PubMed

    Gillis, Patricia L; McInnis, Rodney; Salerno, Joseph; de Solla, Shane R; Servos, Mark R; Leonard, Erin M

    2017-01-01

    The substantial increase in urbanization worldwide has resulted in higher emissions of wastewater to riverine systems near urban centers, which often impairs aquatic populations and communities. This study examined the effect of urbanization on freshwater mussel populations, including Species at Risk in two rivers receiving wastewater. The influence of anthropogenic activities was assessed in a watershed in the Laurentian Great Lakes basin, one that historically supported one of the most diverse mussel faunas in Canada. In the Grand River (ON), four sites along a 60km reach spanning from an upstream reference site to an urban-impacted downstream area were examined. In the Speed River, mussel populations at six sites along a 10km reach, selected to bracket specific anthropogenic inputs and structures were assessed. A semi-quantitative visual search method revealed that catch per unit effort in the Grand River declined by >60% from the upstream reference site to the area downstream of an urban center. The size (length) frequency distribution of the most abundant species, Lasmigona costata, was significantly (p≤0.008) different upstream of the majority of urban inputs (45-130mm) compared to downstream of the cities (85-115mm). In the Speed River, impoundments and wastewater treatment plants (WWTP) reduced both the diversity and catch per effort. Most striking were 84 and 95% changes in the number of mussels found on either side of two impoundments, and a 98% drop in mussels immediately downstream of a WWTP outfall. These population level effects of decreased abundance and underrepresentation of smaller mussels downstream of the urban area correspond to previously documented impacts at the biochemical and whole organism level of biological organization in wild mussels at this location. Our results demonstrate that poor water quality and physical barriers in urban environments continue to impair susceptible populations and communities of aquatic animals. Crown

  7. Procedures for conducting underwater searches for invasive mussels (Dreissena sp.)

    USGS Publications Warehouse

    Adams, Noah

    2010-01-01

    Zebra mussels (Dreissena polymorpha) were first detected in the Great Lakes in 1988. They were likely transported as larvae or young adults inside the ballast tanks of large ocean-going ships originating from Europe. Since their introduction, they have spread throughout the Eastern, Midwestern, and Southern United States. In 2007, Quagga mussels (Dreissena rostriformis bugensis) were found in the Western United States in Lake Mead, Nevada; part of the Lower Colorado River Basin. State and Federal managers are concerned that the mussels (hereafter referred to as dreissenid mussels or mussels) will continue to spread to the Columbia River Basin and have a major impact on the region?s ecosystem, water delivery infrastructure, hydroelectric projects, and the economy. The transport and use of recreational watercraft throughout the Western United States could easily result in spreading mussels to the Columbia River Basin. The number of recreational watercraft using Lake Mead can range from 350 to 3,500 a day (Bryan Moore, National Park Service, oral commun., June 21, 2008). Because recreational watercrafts are readily moved around and mussels may survive for a period of time when they are out of the water, there is a high potential to spread mussels from Lake Mead to other waterways in the Western United States. Efforts are being made to prevent the spread of mussels; however, there is great concern that these efforts will not be 100 percent successful. When prevention efforts fail, early detection of mussels may provide an opportunity to implement rapid response management actions to minimize the impact. Control and eradication efforts are more likely to be successful if they are implemented when the density of mussels is low and the area of infestation is small. Once the population grows and becomes established, the mussels are extremely difficult, if not impossible, to control. Although chemicals may be used to kill the mussels, the chemicals that are currently

  8. Realistic mixture of illicit drugs impaired the oxidative status of the zebra mussel (Dreissena polymorpha).

    PubMed

    Parolini, Marco; Magni, Stefano; Castiglioni, Sara; Zuccato, Ettore; Binelli, Andrea

    2015-06-01

    Illicit drugs are considered to be emerging aquatic pollutants since they are commonly found in freshwater ecosystems in the high ng L(-1) to low μg L(-1) range concentrations. Although the environmental occurrence of the most common psychoactive compounds is well known, recently some investigations showed their potential toxicity toward non-target aquatic organisms. However, to date, these studies completely neglected that organisms in the real environment are exposed to a complex mixture, which could lead to dissimilar adverse effects. The present study investigated the oxidative alterations of the freshwater bivalve Dreissena polymorpha induced by a 14-d exposure to an environmentally relevant mixture of the most common illicit drugs found in the aquatic environment, namely cocaine (50 ng L(-1)), benzoylecgonine (300 ng L(-1)), amphetamine (300 ng L(-1)), morphine (100 ng L(-1)) and 3,4-methylenedioxymethamphetamine (50 ng L(-1)). The total oxidant status (TOS) was measured to investigate the increase in the reactive oxygen species' levels, while the activity of antioxidant enzymes and glutathione S-transferase were measured to note the eventual imbalances between pro-oxidant and antioxidant molecules. In addition, oxidative damage was assessed by measuring the levels of lipid peroxidation and protein carbonylation. Significant time-dependent increases of all the antioxidant activities were induced by the mixture. Moreover, the illicit drug mixture significantly increased the levels of carbonylated proteins and caused a slight variation in lipid peroxidation. Our results showed that a mixture of illicit drugs at realistic environmental concentrations can impair the oxidative status of the zebra mussel, posing a serious hazard to the health status of this bivalve species. Copyright © 2015 Elsevier Ltd. All rights reserved.

  9. Population assessment and potential functional roles of native mussels in the Upper Mississippi River

    USGS Publications Warehouse

    Newton, Teresa J.; Zigler, Steven J.; Rogala, James T.; Gray, Brian R.; Davis, Mike

    2011-01-01

    1. Despite a heightened global concern for native mussels, fundamental research on mussel ecology in large rivers is lacking. These gaps in knowledge about where mussels occur, and why, are limiting habitat restoration activities. 2. Large-scale systematic surveys for native mussels in three reaches of the Upper Mississippi River documented mussel communities composed of 16–23 species and ranging from 2.9–4.5 live mussels m-2 that were actively recruiting new cohorts into their populations (87–100% of the species were found as juveniles 5 years old). Estimates of mean tissue biomass and production in these reaches ranged from 2.1–3.1 g C m-2 and 0.4–0.6 g C m-2year-1, respectively. 3. Mussels filtered a significant amount of water (range, 0.05–0.07 m3m-2d-1) over a 480 km reach of the Upper Mississippi River — amounting to a filtration rate of 53.1 million m3day-1. The filtration rate of mussels as a percentage of river discharge ranged from 0.5–1.4% at high flows (5% exceedance), from 1.5–4.4% at moderate flows (50% exceedance) and from 4.4–12.2% during low flows (95% exceedance). 4. Collectively, these data suggest that native mussels play an integral role in this ecosystem by sequestering suspended materials that can be used by other benthic organisms.

  10. The threat of climate change to freshwater pearl mussel populations.

    PubMed

    Hastie, Lee C; Cosgrove, Peter J; Ellis, Noranne; Gaywood, Martin J

    2003-02-01

    Changes in climate are occurring around the world and the effects on ecosystems will vary, depending on the extent and nature of these changes. In northern Europe, experts predict that annual rainfall will increase significantly, along with dramatic storm events and flooding in the next 50-100 years. Scotland is a stronghold of the endangered freshwater pearl mussel, Margaritifera margaritifera (L.), and a number of populations may be threatened. For example, large floods have been shown to adversely affect mussels, and although these stochastic events were historically rare, they may now be occurring more often as a result of climate change. Populations may also be affected by a number of other factors, including predicted changes in temperature, sea level, habitat availability, host fish stocks and human activity. In this paper, we explain how climate change may impact M. margaritifera and discuss the general implications for the conservation management of this species.

  11. Behavioural and physiological effects of population density on domesticated Zebra Finches (Taeniopygia guttata) held in aviaries.

    PubMed

    Poot, Hanneke; ter Maat, Andries; Trost, Lisa; Schwabl, Ingrid; Jansen, René F; Gahr, Manfred

    2012-02-01

    Zebra Finches (Taeniopygia guttata) are highly social and monogamous birds that display relatively low levels of aggression and coordinate group life mainly by means of vocal communication. In the wild, small groups may congregate to larger flocks of up to 150-350 birds. Little is known, however, about possible effects of population density on development in captivity. Investigating density effects on physiology and behaviour might be helpful in identifying optimal group size, in order to optimise Zebra Finch wellbeing. A direct effect of population density on development and reproduction was found: birds in lower density conditions produced significantly more and larger (body mass, tarsus length) surviving offspring than birds in high density conditions. Furthermore, offspring in low density aviaries produced slightly longer song motifs and more different syllables than their tutors, whereas offspring in high density aviaries produced shorter motifs and a smaller or similar number of different syllables than their tutors. Aggression levels within the populations were low throughout the experiment, but the number of aggressive interactions was significantly higher in high density aviaries. Baseline corticosterone levels did not differ significantly between high- and low density aviaries for either adult or offspring birds. On day 15 post hatching, brood size and baseline corticosterone levels were positively correlated. On days 60 and 100 post hatching this correlation was no longer present. The results of this study prove that population density affects various aspects of Zebra Finch development, with birds living in low population density conditions having an advantage over those living under higher population density conditions. Copyright © 2011 Elsevier Inc. All rights reserved.

  12. Population ecology of the gulf ribbed mussel across a salinity gradient: recruitment, growth and density

    USGS Publications Warehouse

    Honig, Aaron; Supan, John; LaPeyre, Megan K.

    2015-01-01

    Benthic intertidal bivalves play an essential role in estuarine ecosystems by contributing to habitat provision, water filtration, and promoting productivity. As such, changes that impact population distributions and persistence of local bivalve populations may have large ecosystem level consequences. Recruitment, growth, mortality, population size structure and density of the gulf coast ribbed mussel, Geukensia granosissima, were examined across a salinity gradient in southeastern Louisiana. Data were collected along 100-m transects at interior and edge marsh plots located at duplicate sites in upper (salinity ~4 psu), central (salinity ~8 psu) and lower (salinity ~15 psu) Barataria Bay, Louisiana, U.S.A. Growth, mortality and recruitment were measured in established plots from April through November 2012. Mussel densities were greatest within the middle bay (salinity ~8) regardless of flooding regime, but strongly associated with highest stem densities of Juncus roemerianus vegetation. Mussel recruitment, growth, size and survival were significantly higher at mid and high salinity marsh edge sites as compared to all interior marsh and low salinity sites. The observed patterns of density, growth and mortality in Barataria Bay may reflect detrital food resource availability, host vegetation community distribution along the salinity gradient, salinity tolerance of the mussel, and reduced predation at higher salinity edge sites.

  13. Zebra Stripes through the Eyes of Their Predators, Zebras, and Humans.

    PubMed

    Melin, Amanda D; Kline, Donald W; Hiramatsu, Chihiro; Caro, Tim

    2016-01-01

    The century-old idea that stripes make zebras cryptic to large carnivores has never been examined systematically. We evaluated this hypothesis by passing digital images of zebras through species-specific spatial and colour filters to simulate their appearance for the visual systems of zebras' primary predators and zebras themselves. We also measured stripe widths and luminance contrast to estimate the maximum distances from which lions, spotted hyaenas, and zebras can resolve stripes. We found that beyond ca. 50 m (daylight) and 30 m (twilight) zebra stripes are difficult for the estimated visual systems of large carnivores to resolve, but not humans. On moonless nights, stripes are difficult for all species to resolve beyond ca. 9 m. In open treeless habitats where zebras spend most time, zebras are as clearly identified by the lion visual system as are similar-sized ungulates, suggesting that stripes cannot confer crypsis by disrupting the zebra's outline. Stripes confer a minor advantage over solid pelage in masking body shape in woodlands, but the effect is stronger for humans than for predators. Zebras appear to be less able than humans to resolve stripes although they are better than their chief predators. In conclusion, compared to the uniform pelage of other sympatric herbivores it appears highly unlikely that stripes are a form of anti-predator camouflage.

  14. Strong effects of predation by fishes on an invasive macroinvertebrate in a large floodplain river

    USGS Publications Warehouse

    Bartsch, M.R.; Bartsch, L.A.; Gutreuter, S.

    2005-01-01

    We assessed the effects of fish predation on zebra mussels (Dreissena polymorpha) in Navigation Pool 8 of the Upper Mississippi River from 13 May to 5 October, 1998. Concrete-block samplers were deployed at 18 randomly chosen sites in the main-channel border, with 6 sites in the upper, middle, and lower segments of the pool. Two blocks, 1 of which was enclosed in a cage to exclude large predatory fishes, were deployed at each site. After 145 d, blocks were retrieved from 12 of the 18 sites, and zebra mussels were found on all blocks. Densities of zebra mussels were higher on caged blocks than uncaged blocks, and the magnitudes of the differences varied spatially. Mean mussel densities on uncaged blocks were reduced by 66%, 86%, and 20% compared to caged blocks in the upper, middle, and lower pool segments, respectively, over the 145-d interval. Mean daily instantaneous zebra mussel mortality rates from large predators ranged from 0.0016 to 0.0138. Similarly, biomass of zebra mussels was higher on caged than uncaged blocks. Mean mussel biomass on uncaged blocks was reduced by 64% pool-wide, relative to biomass on caged blocks. Zebra mussels were consumed by at least 6 fish taxa including redhorse stickers (Moxostoma spp.), common carp (Cyprinus carpio), bluegill (Lepomis macrochirus), quillback carpsucker (Carpiodes cyprinus), flathead catfish (Pylodictis olivaris), and freshwater drum (Aplodinotus grunniens). Fish predation had an important moderating effect on zebra mussel demography in Pool 8.

  15. Freshwater mussel population status and habitat quality in the Clinch River, Virginia and Tennessee, USA: a featured collection

    USGS Publications Warehouse

    Zipper, Carl E.; Beaty, Braven; Johnson, Gregory C.; Jones, Jess W.; Krstolic, Jennifer Lynn; Ostby, Brett J.K.; Wolfe, William J.; Donovan, Patricia

    2014-01-01

    The Clinch River of southwestern Virginia and northeastern Tennessee is arguably the most important river for freshwater mussel conservation in the United States. This featured collection presents investigations of mussel population status and habitat quality in the Clinch River. Analyses of historic water- and sediment-quality data suggest that water column ammonia and water column and sediment metals, including Cu and Zn, may have contributed historically to declining densities and extirpations of mussels in the river's Virginia sections. These studies also reveal increasing temporal trends for dissolved solids concentrations throughout much of the river's extent. Current mussel abundance patterns do not correspond spatially with physical habitat quality, but they do correspond with specific conductance, dissolved major ions, and water column metals, suggesting these and/or associated constituents as factors contributing to mussel declines. Mussels are sensitive to metals. Native mussels and hatchery-raised mussels held in cages in situ accumulated metals in their body tissues in river sections where mussels are declining. Organic compound and bed-sediment contaminant analyses did not reveal spatial correspondences with mussel status metrics, although potentially toxic levels were found. Collectively, these studies identify major ions and metals as water- and sediment-quality concerns for mussel conservation in the Clinch River.

  16. In vivo exposure of Dreissena polymorpha mussels to the quinones menadione and lawsone: menadione is more toxic to mussels than lawsone.

    PubMed

    Osman, A M; Rotteveel, S; den Besten, P J; van Noort, P C M

    2004-01-01

    The principal aim of this study was to assess whether the two quinones, menadione (2-methyl-1,4-naphthoquinone) and lawsone (2-hydroxy-1,4-naphthoquinone), elicit differential toxicity in mussels as has been reported for higher organisms. Therefore, the effects of short-term (48 h) and long-term (20 days) exposure of the two quinones at concentrations of 0.56 and 1 mg l(-1) to zebra mussels, Dreissena polymorpha, under laboratory conditions were studied. After the short-term exposure, the specific activities of the two-electron quinone oxidoreductase (DT-diaphorase) and the one-electron catalysing quinone reductases NADPH-cytochrome c reductase and NADH-cytochrome c reductase were determined in the gills and the rest of the soft tissues (soft mussel tissues minus the gills) of both treated and control mussels. At the higher concentrations of menadione and lawsone used, a significant reduction of the activity of NADPH-cytochrome c reductase in the gills and in the rest of the soft mussel tissues (by 33-34% and 31-43%, respectively) was observed. The activities of DT-diaphorase and NADH-cytochrome c reductase were not significantly affected. Interestingly, DT-diaphorase was observed in the gills, an organ requiring protection against antioxidants. Furthermore, a single-cell electrophoretic assay (comet assay) performed with gill cells to assess DNA damage by the quinones did not show any significant difference between the treated and the control organisms. This indicates that the formation of reactive species by the quinone metabolism in vivo in the mussels was possibly suppressed through the concerted action of DT-diaphorase and antioxidant enzymes. The results of in vitro experiments with gill extracts confirmed the protective role of DT-diaphorase. The rate of the two-electron quinone reduction was found to be five times that of the one-electron quinone reduction. The results of the long-term exposure unambiguously demonstrated that in mussels menadione, unlike in

  17. Controlling populations of invasive pygmy mussel (Xenostrobus securis) through citizen science and environmental DNA.

    PubMed

    Miralles, Laura; Dopico, Eduardo; Devlo-Delva, Floriaan; Garcia-Vazquez, Eva

    2016-09-15

    Early detection of dangerous exotic species is crucial for stopping marine invasions. The New Zealand pygmy mussel Xenostrobus securis is a problematic species in coasts of temperate regions in the northern hemisphere. In this study we have controlled a population of this invader that recently expanded in a north Iberian estuary with both a participatory approach involving researchers and citizens, and employing a sensitive eDNA-based tool to monitor the population expansion in the estuary. Results demonstrate successful eradication of pygmy mussels in the outer part of the estuary with citizen science and the practical utility of eDNA for controlling biological invasions. Copyright © 2016 Elsevier Ltd. All rights reserved.

  18. SEASONAL VARIABILTIY LIPIDS, LIPID CLASSES AND PCBS IN INDIGENOUS POPULATIONS OF RIBBED MUSSELS, MODIOLUS DEMISSUS

    EPA Science Inventory

    Two indigenous ribbed mussel (Modiolus demissus) populations were sampled approximately every four weeks during 1997 to investigate the seasonal variability of total lipids, lipid classes, and polychlorinated biphenyl (PCB) concentrations. One population was located in a highly c...

  19. Zebra Stripes through the Eyes of Their Predators, Zebras, and Humans

    PubMed Central

    Melin, Amanda D.; Kline, Donald W.; Hiramatsu, Chihiro; Caro, Tim

    2016-01-01

    The century-old idea that stripes make zebras cryptic to large carnivores has never been examined systematically. We evaluated this hypothesis by passing digital images of zebras through species-specific spatial and colour filters to simulate their appearance for the visual systems of zebras’ primary predators and zebras themselves. We also measured stripe widths and luminance contrast to estimate the maximum distances from which lions, spotted hyaenas, and zebras can resolve stripes. We found that beyond ca. 50 m (daylight) and 30 m (twilight) zebra stripes are difficult for the estimated visual systems of large carnivores to resolve, but not humans. On moonless nights, stripes are difficult for all species to resolve beyond ca. 9 m. In open treeless habitats where zebras spend most time, zebras are as clearly identified by the lion visual system as are similar-sized ungulates, suggesting that stripes cannot confer crypsis by disrupting the zebra’s outline. Stripes confer a minor advantage over solid pelage in masking body shape in woodlands, but the effect is stronger for humans than for predators. Zebras appear to be less able than humans to resolve stripes although they are better than their chief predators. In conclusion, compared to the uniform pelage of other sympatric herbivores it appears highly unlikely that stripes are a form of anti-predator camouflage. PMID:26799935

  20. Comparison of population genetic patterns in two widespread freshwater mussels with contrasting life histories in western North America.

    PubMed

    Mock, K E; Brim Box, J C; Chong, J P; Furnish, J; Howard, J K

    2013-12-01

    We investigate population genetic structuring in Margaritifera falcata, a freshwater mussel native to western North America, across the majority of its geographical range. We find shallow rangewide genetic structure, strong population-level structuring and very low population diversity in this species, using both mitochondrial sequence and nuclear microsatellite data. We contrast these patterns with previous findings in another freshwater mussel species group (Anodonta californiensis/A. nuttalliana) occupying the same continental region and many of the same watersheds. We conclude that differences are likely caused by contrasting life history attributes between genera, particularly host fish requirements and hermaphroditism. Further, we demonstrate the occurrence of a 'hotspot' for genetic diversity in both groups of mussels, occurring in the vicinity of the lower Columbia River drainage. We suggest that stream hierarchy may be responsible for this pattern and may produce similar patterns in other widespread freshwater species. © 2013 John Wiley & Sons Ltd.

  1. Dispersal barriers and isolation among deep-sea mussel populations (Mytilidae: Bathymodiolus) from eastern Pacific hydrothermal vents.

    PubMed

    Won, Y; Young, C R; Lutz, R A; Vrijenhoek, R C

    2003-01-01

    Deep-sea hydrothermal vent species are widely dispersed among habitat islands found along the global mid-ocean ridge system. We examine factors that affect population structure, gene flow and isolation in vent-endemic mussels of the genus Bathymodiolus from the eastern Pacific Ocean. Mussels were sampled from localities including the Galapagos Rift (GAR, 0 degrees 48' N; 86 degrees 10' W) and the East Pacific Rise (EPR, 13 degrees N to 32 degrees S latitude) across a maximum distance of 4900 km. The sampled range crossed a series of topographical features that interrupt linear aspects of the ridge system, and it encompassed regions of strong cross-axis currents that could impede along-axis dispersal of mussel larvae. Examinations of mitochondrial DNA sequences and allozyme variation revealed significant barriers to gene flow along the ridge axis. All populations from the GAR and EPR from 13 degrees N to 11 degrees S were homogeneous genetically and appeared to experience unimpeded high levels of interpopulational gene flow. In contrast, mussels from north and south of the Easter Microplate were highly divergent (4.4%), possibly comprising sister-species that diverged after formation of the microplate approximately 4.5 Ma. Strong cross-axis currents associated with inflated bathymetry of the microplate region may reinforce isolation across this region.

  2. Rapid divergence of mussel populations despite incomplete barriers to dispersal.

    PubMed

    Maas, Diede L; Prost, Stefan; Bi, Ke; Smith, Lydia L; Armstrong, Ellie E; Aji, Ludi P; Toha, Abdul Hamid A; Gillespie, Rosemary G; Becking, Leontine E

    2018-04-01

    Striking genetic structure among marine populations at small spatial scales is becoming evident with extensive molecular studies. Such observations suggest isolation at small scales may play an important role in forming patterns of genetic diversity within species. Isolation-by-distance, isolation-by-environment and historical priority effects are umbrella terms for a suite of processes that underlie genetic structure, but their relative importance at different spatial and temporal scales remains elusive. Here, we use marine lakes in Indonesia to assess genetic structure and assess the relative roles of the processes in shaping genetic differentiation in populations of a bivalve mussel (Brachidontes sp.). Marine lakes are landlocked waterbodies of similar age (6,000-10,000 years), but with heterogeneous environments and varying degrees of connection to the sea. Using a population genomic approach (double-digest restriction-site-associated DNA sequencing), we show strong genetic structuring across populations (range F ST : 0.07-0.24) and find limited gene flow through admixture plots. At large spatial scales (>1,400 km), a clear isolation-by-distance pattern was detected. At smaller spatial scales (<200 km), this pattern is maintained, but accompanied by an association of genetic divergence with degree of connection. We hypothesize that (incomplete) dispersal barriers can cause initial isolation, allowing priority effects to give the numerical advantage necessary to initiate strong genetic structure. Priority effects may be strengthened by local adaptation, which the data may corroborate by showing a high correlation between mussel genotypes and temperature. Our study indicates an often-neglected role of (evolution-mediated) priority effects in shaping population divergence. © 2018 The Authors. Molecular Ecology published by John Wiley & Sons Ltd.

  3. Dreissenid mussels are not a "dead end" in Great Lakes food webs

    USGS Publications Warehouse

    Madenijan, Charles P.; Pothoven, Steven A.; Schneeberger, Philip J.; Ebener, Mark P.; Mohr, Lloyd C.; Nalepa, Thomas F.; Bence, James R.

    2010-01-01

    Dreissenid mussels have been regarded as a “dead end” in Great Lakes food webs because the degree of predation on dreissenid mussels, on a lakewide basis, is believed to be low. Waterfowl predation on dreissenid mussels in the Great Lakes has primarily been confined to bays, and therefore its effects on the dreissenid mussel population have been localized rather than operating on a lakewide level. Based on results from a previous study, annual consumption of dreissenid mussels by the round goby (Neogobius melanostomus) population in central Lake Erie averaged only 6 kilotonnes (kt; 1 kt = one thousand metric tons) during 1995–2002. In contrast, our coupling of lake whitefish (Coregonus clupeaformis) population models with a lake whitefish bioenergetics model revealed that lake whitefish populations in Lakes Michigan and Huron consumed 109 and 820 kt, respectively, of dreissenid mussels each year. Our results indicated that lake whitefish can be an important predator on dreissenid mussels in the Great Lakes, and that dreissenid mussels do not represent a “dead end” in Great Lakes food webs. The Lake Michigan dreissenid mussel population has been estimated to be growing more than three times faster than the Lake Huron dreissenid mussel population during the 2000s. One plausible explanation for the higher population growth rate in Lake Michigan would be the substantially higher predation rate by lake whitefish on dreissenid mussels in Lake Huron.

  4. IUCN classification zones concord with, but underestimate, the population genetic structure of the zebra shark Stegostoma fasciatum in the Indo-West Pacific.

    PubMed

    Dudgeon, C L; Broderick, D; Ovenden, J R

    2009-01-01

    The Indo-West Pacific (IWP), from South Africa in the western Indian Ocean to the western Pacific Ocean, contains some of the most biologically diverse marine habitats on earth, including the greatest biodiversity of chondrichthyan fishes. The region encompasses various densities of human habitation leading to contrasts in the levels of exploitation experienced by chondrichthyans, which are targeted for local consumption and export. The demersal chondrichthyan, the zebra shark, Stegostoma fasciatum, is endemic to the IWP and has two current regional International Union for the Conservation of Nature (IUCN) Red List classifications that reflect differing levels of exploitation: 'Least Concern' and 'Vulnerable'. In this study, we employed mitochondrial ND4 sequence data and 13 microsatellite loci to investigate the population genetic structure of 180 zebra sharks from 13 locations throughout the IWP to test the concordance of IUCN zones with demographic units that have conservation value. Mitochondrial and microsatellite data sets from samples collected throughout northern Australia and Southeast Asia concord with the regional IUCN classifications. However, we found evidence of genetic subdivision within these regions, including subdivision between locations connected by habitat suitable for migration. Furthermore, parametric F(ST) analyses and Bayesian clustering analyses indicated that the primary genetic break within the IWP is not represented by the IUCN classifications but rather is congruent with the Indonesian throughflow current. Our findings indicate that recruitment to areas of high exploitation from nearby healthy populations in zebra sharks is likely to be minimal, and that severe localized depletions are predicted to occur in zebra shark populations throughout the IWP region.

  5. Invasive species research to meet the needs of resource management and planning.

    PubMed

    Papeş, M; Sällström, M; Asplund, T R; Vander Zanden, M J

    2011-10-01

    As zebra mussels (Dreissena polymorpha) continue to spread among inland lakes of the United States and Canada, there is growing interest from professionals, citizens, and other stakeholders to know which lakes are likely to be colonized by zebra mussels. Thus, we developed a classification of lake suitability for zebra mussels on the basis of measured or estimated concentrations of dissolved calcium in lake water and applied the classification to >11,500 lakes in Wisconsin and the Upper Peninsula of Michigan. The majority of lakes (58%) were classified as unsuitable (<10 mg/L Ca) for survival and reproduction of zebra mussels, 27% were identified as suitable (≥21 mg/L Ca), and 15% were classified as borderline suitable (≥10 and <21 mg/L Ca). Of the 77 inland lakes with confirmed zebra mussel records for which data on dissolved calcium were available, our method classified 74 as suitable and 3 as borderline suitable. To communicate this lake-specific suitability information and to help prioritize regional efforts to monitor and prevent the expansion of zebra mussels and other invasive species, we developed a web-based interface (available from http://www.aissmartprevention.wisc.edu/). Although we are still uncertain of how access to suitability information ultimately affects decision making, we believe this is a useful case study of building communication channels among researchers, practitioners, and the public. ©2011 Society for Conservation Biology.

  6. Optimal sampling design for estimating spatial distribution and abundance of a freshwater mussel population

    USGS Publications Warehouse

    Pooler, P.S.; Smith, D.R.

    2005-01-01

    We compared the ability of simple random sampling (SRS) and a variety of systematic sampling (SYS) designs to estimate abundance, quantify spatial clustering, and predict spatial distribution of freshwater mussels. Sampling simulations were conducted using data obtained from a census of freshwater mussels in a 40 X 33 m section of the Cacapon River near Capon Bridge, West Virginia, and from a simulated spatially random population generated to have the same abundance as the real population. Sampling units that were 0.25 m 2 gave more accurate and precise abundance estimates and generally better spatial predictions than 1-m2 sampling units. Systematic sampling with ???2 random starts was more efficient than SRS. Estimates of abundance based on SYS were more accurate when the distance between sampling units across the stream was less than or equal to the distance between sampling units along the stream. Three measures for quantifying spatial clustering were examined: Hopkins Statistic, the Clumping Index, and Morisita's Index. Morisita's Index was the most reliable, and the Hopkins Statistic was prone to false rejection of complete spatial randomness. SYS designs with units spaced equally across and up stream provided the most accurate predictions when estimating the spatial distribution by kriging. Our research indicates that SYS designs with sampling units equally spaced both across and along the stream would be appropriate for sampling freshwater mussels even if no information about the true underlying spatial distribution of the population were available to guide the design choice. ?? 2005 by The North American Benthological Society.

  7. Changing perspectives on pearly mussels, North America's most imperiled animals

    USGS Publications Warehouse

    Strayer, David L.; Downing, John A.; Haag, Wendell R.; King, Timothy L.; Layzer, James B.; Newton, Teresa J.; Nichols, S. Jerrine

    2004-01-01

    Pearly mussels (Unionacea) are widespread, abundant, and important in freshwater ecosystems around the world. Catastrophic declines in pearly mussel populations in North America and other parts of the world have led to a flurry of research on mussel biology, ecology, and conservation. Recent research on mussel feeding, life history, spatial patterning, and declines has augmented, modified, or overturned long-held ideas about the ecology of these animals. Pearly mussel research has begun to benefit from and contribute to current ideas about suspension feeding, life-history theory, metapopulations, flow refuges, spatial patterning and its effects, and management of endangered species. At the same time, significant gaps in understanding and apparent paradoxes in pearly mussel ecology have been exposed. To conserve remaining mussel populations, scientists and managers must simultaneously and aggressively pursue both rigorous research and conservation actions.

  8. Variations in the reproductive cycle of Dreissena polymorpha in Europe, Russia, and North America

    USGS Publications Warehouse

    Nichols, Susan Jerrine

    1996-01-01

    The reproductive cycle of the zebra mussel (Dreissena polymorpha) is highly variable throughout its range in Europe, Russia, and North America. The environmental factors influencing this variation are poorly understood, but successful reproduction is occurring in areas where it was initially believed that adult zebra mussels could not survive (i.e., southern United States). The differences in mussel reproduction occurring from site-to-site make it difficult to predict timing of specific events, such as the start of larval production, that are important in initiating containment or control procedures. For example, the amount of time required for a fertilized egg to develop into a juvenile mussel can be as short as 8 days, or as long as 240 days. Release of gametes by adults can be a highly synchronized event, focused over a 1-2 week period, or it can be completely non-synchronized, occurring throughout the year. Zebra mussels in some localities start spawning at water temperatures of 12-13A?C, but do not start until water temperatures reaches 22A?C at other sites. While some of this variability in reproductive behavior stems from mussel adaptation to local conditions, part is due to difficulties in sampling these events. It is difficult to determine reproductive success of a specific population because of the problems in separating locally produced larvae from larvae drifting in from other areas. Further research is needed not only on the relationship between reproduction and environment at the community level, but also on the variability in response of individual mussels.

  9. Changing perspectives on pearly mussels, North America's most imperiled animals

    Treesearch

    David L. Strayer; John A. Downing; Wendell R. Haag; Timothy L. King; James B. Layzer; Teresa J. Newton; S. Jerrine Nichols

    2004-01-01

    Pearly mussels (Unionacea) are widespread, abundant, and important in freshwater ecosystems around the world. Catastrophic declines in pearly mussel populations in North America and other parts of the world have led to a flurry of research on mussel biology, ecology, and conservation. Recent research on mussel feeding, life history, spatial...

  10. Zebra Crossing Spotter: Automatic Population of Spatial Databases for Increased Safety of Blind Travelers

    PubMed Central

    Ahmetovic, Dragan; Manduchi, Roberto; Coughlan, James M.; Mascetti, Sergio

    2016-01-01

    In this paper we propose a computer vision-based technique that mines existing spatial image databases for discovery of zebra crosswalks in urban settings. Knowing the location of crosswalks is critical for a blind person planning a trip that includes street crossing. By augmenting existing spatial databases (such as Google Maps or OpenStreetMap) with this information, a blind traveler may make more informed routing decisions, resulting in greater safety during independent travel. Our algorithm first searches for zebra crosswalks in satellite images; all candidates thus found are validated against spatially registered Google Street View images. This cascaded approach enables fast and reliable discovery and localization of zebra crosswalks in large image datasets. While fully automatic, our algorithm could also be complemented by a final crowdsourcing validation stage for increased accuracy. PMID:26824080

  11. Toxicity of potassium chloride to veliger and byssal stage dreissenid mussels related to water quality

    USGS Publications Warehouse

    Moffitt, Christine M.; Stockton-Fiti, Kelly A.; Claudi, Renata

    2016-01-01

    Natural resource managers are seeking appropriate chemical eradication and control protocols for infestations of zebra mussels, Dreissena polymorpha (Pallas, 1769), and quagga mussels. D. rostiformis bugensis (Andrusov, 1897) that have limited effect on non-target species. Applications of low concentrations of potassium salt (as potash) have shown promise for use where the infestation and treatment can be contained or isolated. To further our understanding of such applications and obtain data that could support a pesticide registration, we conducted studies of the acute and chronic toxicity of potassium chloride to dreissenid mussels in four different water sources from infested and non-infested locations (ground water from northern Idaho, surface water from the Snake River, Idaho, USA, surface water from Lake Ontario, Ontario, Canada, and surface water from the Colorado River, Arizona, USA). We found short term exposure of veligers (< 24 h) to concentrations of 960 mg/L KCl produced rapid mortality in water from three locations, but veligers tested in Colorado River water were resistant. We used probit models to compare the mortality responses, predicted median lethal times and 95% confidence intervals. In separate experiments, we explored the sensitivity of byssal stage mussels in chronic exposures (>29 d) at concentrations of 100 and 200 mg/L KCl. Rapid mortality occurred within 10 d of exposure to concentrations of 200 mg/L KCl, regardless of water source. Kaplan-Meier estimates of mean survival of byssal mussels in 100 mg/L KCl prepared in surface water from Idaho and Lake Ontario were 4.9 or 6.9 d, respectively; however, mean survival of mussels tested in the Colorado River water was > 23 d. The sodium content of the Colorado River water was nearly three times that measured in waters from the other locations, and we hypothesized sodium concentrations may affect mussel survival. To test our hypothesis, we supplemented Snake River and Lake Ontario water with Na

  12. The role of host abundance in regulating populations of freshwater mussels with parasitic larvae

    Treesearch

    Wendell R. Haag; James A. Stoeckel

    2015-01-01

    Host–parasite theory makes predictions about the influence of host abundance, competition for hosts, and parasite transmission on parasite population size, but many of these predictions are not well tested empirically. We experimentally examined these factors in ponds using two species of freshwater mussels with parasitic larvae that infect host fishes via different...

  13. Relations of Environmental Factors with Mussel-Species Richness in the Neversink River, New York

    USGS Publications Warehouse

    Baldigo, Barry P.; Ernst, Anne G.; Schuler, George E.; Apse, Colin D.

    2007-01-01

    INTRODUCTION Declines in the distribution, abundance, and diversity of freshwater-mussel species (family Unionidae1) have been reported worldwide (Bogan, 1993; Strayer and Jirka, 1997). The principal causes of the observed declines are difficult to confirm, however, because only a few of the many factors that affect mussel-species populations have been identified (Strayer and Ralley, 1993; Strayer, 1999; Baldigo and others, 2003; Strayer and others, 2006). The Neversink River, which drains the Catskill Mountains in southeastern New York (fig. 1), contains seven species of mussels (Strayer and Ralley, 1991; Strayer and Jirka, 1997). Populations of the endangered dwarf wedgemussel (Alasmidonta heterodon) and the threatened swollen wedgemussel (Alasmidonta varicosa) coexist with other unionid mussels in the Neversink River (Strayer and Ralley, 1991, 1993; Baldigo and others, 2003). Dwarf wedgemussel populations had previously been found only downstream from the site of an abandoned dam in the lower part of the river at Cuddebackville (fig. 1), and swollen wedgemussels were only found in the lower and middle reaches of the river. The limited distribution of these two species suggests that they may be susceptible to local extinctions. The distribution of mussel populations can be limited by impoundments. Mussel larvae develop in species-specific host fish; thus, impoundments that restrict passage of these host fish also restrict the extent of mussels. The Neversink River is impounded by the Neversink Reservoir [241 square kilometers (km2)], a major source of drinking water for the City of New York, and was also impounded 50 km downstream by the Cuddebackville Dam until 2004, when the latter was removed by The Nature Conservancy (TNC) and the U.S. Army Corps of Engineers to improve fish passage. The removal of this dam has provided previously unavailable habitat for diadromous and other fish species that act as hosts for rare mussel species. In addition, releases from

  14. Influences of water and sediment quality and hydrologic processes on mussels in the Clinch River

    USGS Publications Warehouse

    Johnson, Gregory C.; Krstolic, Jennifer L.; Ostby, Brett J.K.

    2014-01-01

    Segments of the Clinch River in Virginia have experienced declining freshwater mussel populations during the past 40 years, while other segments of the river continue to support some of the richest mussel communities in the country. The close proximity of these contrasting reaches provides a study area where differences in climate, hydrology, and historic mussel distribution are minimal. The USGS conducted a study between 2009 and 2011 to evaluate possible causes of the mussel declines. Evaluation of mussel habitat showed no differences in physical habitat quality, leaving water and sediment quality as possible causes for declines. Three years of continuous water-quality data showed higher turbidity and specific conductance in the reaches with low-quality mussel assemblages compared to reaches with high-quality mussel assemblages. Discrete water-quality samples showed higher major ions and metals concentrations in the low-quality reach. Base-flow samples contained high major ion and metal concentrations coincident to low-quality mussel populations. These results support a conceptual model of dilution and augmentation where increased concentrations of major ions and other dissolved constituents from mined tributaries result in reaches with declining mussel populations. Tributaries from unmined basins provide water with low concentrations of dissolved constituents, diluting reaches of the Clinch River where high-quality mussel populations occur.

  15. Experimental evidence that stripes do not cool zebras.

    PubMed

    Horváth, Gábor; Pereszlényi, Ádám; Száz, Dénes; Barta, András; Jánosi, Imre M; Gerics, Balázs; Åkesson, Susanne

    2018-06-19

    There are as many as 18 theories for the possible functions of the stripes of zebras, one of which is to cool the animal. We performed field experiments and thermographic measurements to investigate whether thermoregulation might work for zebra-striped bodies. A zebra body was modelled by water-filled metal barrels covered with horse, cattle and zebra hides and with various black, white, grey and striped patterns. The barrels were installed in the open air for four months while their core temperature was measured continuously. Using thermography, the temperature distributions of the barrel surfaces were compared to those of living zebras. The sunlit zebra-striped barrels reproduced well the surface temperature characteristics of sunlit zebras. We found that there were no significant core temperature differences between the striped and grey barrels, even on many hot days, independent of the air temperature and wind speed. The average core temperature of the barrels increased as follows: white cattle, grey cattle, real zebra, artificial zebra, grey horse, black cattle. Consequently, we demonstrate that zebra-striped coats do not keep the body cooler than grey coats challenging the hypothesis of a thermoregulatory role of zebra stripes.

  16. Sediment, land use, and freshwater mussels: Prospects and problems

    USGS Publications Warehouse

    Brim-Box, J.; Mossa, J.

    1999-01-01

    The decline in freshwater mussel populations in many river basins throughout North America has been attributed, in part, to land-use modifications that cause changes in sediment regimes. However, the specific associations that mussels have with stream sediments are poorly understood, making it difficult to assess the impacts of changes in sedimentation rates on unionid mussels. Both bed and suspended materials, and concomitant changes in channel form associated with changes in sediment supply, may affect mussels in numerous ways at various stages in their life cycle. Considerable debate and uncertainty remains regarding the strength of associations between sediments and mussels, including whether increased sedimentation is a cause of recent mussel declines. It is important to be aware of appropriate procedures for sampling and analyzing fluvial sediments, and the nature of sediment sources, to adequately assess relationships between unionid mussels and fluvial sediments.

  17. Distribution and ecology of Dreissena polymorpha (pallas) and Dreissena bugensis (andrusov) in the upper Volga basin

    USGS Publications Warehouse

    Shcherbina, G. Kh; Buckler, D.R.

    2006-01-01

    This paper presents data on contemporary distribution patterns of two species of Dreissenidae, the zebra mussel (Dreissena polymorpha) and the Quagga mussel (Dreissena bugensis), and their role in ecosystem processes in the Ivan'kovo, Uglich, Rybinsk, and Gorky Reservoirs of the Upper Volga River basin. The role of zebra mussel was also studied in experimental mesocosms of 15 m3. Maximum abundance and species diversity of macroinvertebrates, especially of leeches, polychaetes, crustaceans, and heterotopic insects, were attained in the portions of reservoirs where Dreissenidae were present and in experimental mesocosms where zebra mussel biomass was the highest. In the mesocosm studies, the presence of zebra mussel druses (colonies) provided shelter for macroinvertebrates, reducing their vulnerability to predation by perch (Perca fluviatills) larvae and yearlings, thereby increasing macroinvertebrate species diversity. It was shown that in addition to its role in aquatic biocenosis (ecological community) formation and water purification, Dreissenidae are important food objects for benthophagous fishes, especially roach (Rutilus rutilus). Examination of intestines of benthophagous fishes showed that the length of Dreissenidae ranged from 5 to 20 mm in roach; from 4 to 14 mm in silver bream (Blicca bjoerkna), and from 2 to 10 mm in bream (Abramis brama). The largest mussels consumed were Quagga mussels up to 30 mm, noted in the predatory cyprinid, ide (Leuciscus idus). Copyright ?? 2006 by ASTM International.

  18. Ecosystem transformations of the Laurentian Great Lake Michigan by nonindigenous biological invaders.

    PubMed

    Cuhel, Russell L; Aguilar, Carmen

    2013-01-01

    Lake Michigan, a 58,000-km(2) freshwater inland sea, is large enough to have persistent basin-scale circulation yet small enough to enable development of approximately balanced budgets for water, energy, and elements including carbon and silicon. Introduction of nonindigenous species-whether through invasion, intentional stocking, or accidental transplantation-has transformed the lake's ecosystem function and habitat structure. Of the 79 nonindigenous species known to have established reproductive populations in the lake, only a few have brought considerable ecological pressure to bear. Four of these were chosen for this review to exemplify top-down (sea lamprey, Petromyzon marinus), middle-out (alewife, Alosa pseudoharengus), and bottom-up (the dreissenid zebra and quagga mussels, Dreissena polymorpha and Dreissena rostriformis bugensis, respectively) transformations of Lake Michigan ecology, habitability, and ultimately physical environment. Lampreys attacked and extirpated indigenous lake trout, the top predator. Alewives outcompeted native planktivorous fish and curtailed invertebrate populations. Dreissenid mussels-especially quagga mussels, which have had a much greater impact than the preceding zebra mussels-moved ecosystem metabolism basin-wide from water column to bottom dominance and engineered structures throughout the lake. Each of these non indigenous species exerted devastating effects on commercial and sport fisheries through ecosystem structure modification.

  19. PIT tags increase effectiveness of freshwater mussel recaptures

    USGS Publications Warehouse

    Kurth, J.; Loftin, C.; Zydlewski, Joseph D.; Rhymer, Judith

    2007-01-01

    Translocations are used increasingly to conserve populations of rare freshwater mussels. Recovery of translocated mussels is essential to accurate assessment of translocation success. We designed an experiment to evaluate the use of passive integrated transponder (PIT) tags to mark and track individual freshwater mussels. We used eastern lampmussels (Lampsilis radiata radiata) as a surrogate for 2 rare mussel species. We assessed internal and external PIT-tag retention in the laboratory and field. Internal tag retention was high (75-100%), and tag rejection occurred primarily during the first 3 wk after tagging. A thin layer of nacre coated internal tags 3 to 4 mo after insertion, suggesting that long-term retention is likely. We released mussels with external PIT tags at 3 field study sites and recaptured them with a PIT pack (mobile interrogation unit) 8 to 10 mo and 21 to 23 mo after release. Numbers of recaptured mussels differed among study sites; however, we found more tagged mussels with the PIT-pack searches with visual confirmation (72-80%) than with visual searches alone (30-47%) at all sites. PIT tags offer improved recapture of translocated mussels and increased accuracy of posttranslocation monitoring. ?? 2007 by The North American Benthological Society.

  20. Genetic management guidelines for captive propagation of freshwater mussels (unionoidea)

    USGS Publications Warehouse

    Jones, J.W.; Hallerman, E.M.; Neves, R.J.

    2006-01-01

    Although the greatest global diversity of freshwater mussels (???300 species) resides in the United States, the superfamily Unionoidea is also the most imperiled taxon of animals in the nation. Thirty-five species are considered extinct, 70 species are listed as endangered or threatened, and approximately 100 more are species of conservation concern. To prevent additional species losses, biologists have developed methods for propagating juvenile mussels for release into the wild to restore or augment populations. Since 1997, mussel propagation facilities in the United States have released over 1 million juveniles of more than a dozen imperiled species, and survival of these juveniles in the wild has been documented. With the expectation of continued growth of these programs, agencies and facilities involved with mussel propagation must seriously consider the genetic implications of releasing captive-reared progeny. We propose 10 guidelines to help maintain the genetic resources of cultured and wild populations. Preservation of genetic diversity will require robust genetic analysis of source populations to define conservation units for valid species, subspecies, and unique populations. Hatchery protocols must be implemented that minimize risks of artificial selection and other genetic hazards affecting adaptive traits of progeny subsequently released to the wild. We advocate a pragmatic, adaptive approach to species recovery that incorporates the principles of conservation genetics into breeding programs, and prioritizes the immediate demographic needs of critically endangered mussel species.

  1. Rapid molecular detection of invasive species in ballast and harbor water by integrating environmental DNA and light transmission spectroscopy.

    PubMed

    Egan, Scott P; Grey, Erin; Olds, Brett; Feder, Jeffery L; Ruggiero, Steven T; Tanner, Carol E; Lodge, David M

    2015-04-07

    Invasive species introduced via the ballast water of commercial ships cause enormous environmental and economic damage worldwide. Accurate monitoring for these often microscopic and morphologically indistinguishable species is challenging but critical for mitigating damages. We apply eDNA sampling, which involves the filtering and subsequent DNA extraction of microscopic bits of tissue suspended in water, to ballast and harbor water sampled during a commercial ship's 1400 km voyage through the North American Great Lakes. Using a lab-based gel electrophoresis assay and a rapid, field-ready light transmission spectroscopy (LTS) assay, we test for the presence of two invasive species: quagga (Dreissena bugensis) and zebra (D. polymorpha) mussels. Furthermore, we spiked a set of uninfested ballast and harbor samples with zebra mussel tissue to further test each assay's detection capabilities. In unmanipulated samples, zebra mussel was not detected, while quagga mussel was detected in all samples at a rate of 85% for the gel assay and 100% for the LTS assay. In the spiked experimental samples, both assays detected zebra mussel in 94% of spiked samples and 0% of negative controls. Overall, these results demonstrate that eDNA sampling is effective for monitoring ballast-mediated invasions and that LTS has the potential for rapid, field-based detection.

  2. Variability in biochemical components of the mussel (Mytilus galloprovincialis) cultured after Prestige oil spill.

    PubMed

    Peteiro, Laura G; Labarta, Uxío; Fernández-Reiriz, María José

    2007-05-01

    The biochemical composition (proteins, carbohydrates, glycogen, total lipids and lipid classes) of the mussel Mytilus galloprovincialis was investigated during an experimental culture using mussel seed from areas with different degree of exposure to the Prestige oil spill. The aim of the study was to identify alterations in the biochemical composition of mussel seed from natural populations commonly used in Galicia for mussel raft culture that might be linked to previous oil exposure. We have selected three mussel seed populations from Pindo, Miranda and Redes, that were characterised in a previous study according to the oil exposure three months after the spill. These populations were transplanted to a raft culture system in the Ría de Ares-Betanzos where our experimental culture followed standard commercial techniques from March 2003 to February 2004. Mussels from Pindo (characterised as the most affected area by the oil spill) showed marked differences in lipid composition with regard to other populations in the content of triacylglycerols, (P<0.001), free fatty acids (P<0.001) and phospholipids (P<0.05) at the onset of the culture. Although these differences in lipid composition might reflect their previous exposition to hydrocarbons, this pattern did not last longer most likely due to depuration of hydrocarbons stored in the tissues or by the development of certain tolerance to PAHs. These significant differences were not detected between Miranda (designed as hardly affected area) and Redes (designed as reference area) which may reflect that Miranda mussels were not affected or only hardly affected by the spill. With the exception of the onset of the culture, biochemical composition showed similar patterns in all mussel populations. Then, the fact of being cultured in a common environment seemed to be more responsible for the long-term variability in the energetic reserve than the origin of the populations or their previous biochemical status.

  3. Single nucleotide polymorphisms in native South American Atlantic coast populations of smooth shelled mussels: hybridization with invasive European Mytilus galloprovincialis.

    PubMed

    Zbawicka, Małgorzata; Trucco, María I; Wenne, Roman

    2018-02-22

    Throughout the world, harvesting of mussels Mytilus spp. is based on the exploitation of natural populations and aquaculture. Aquaculture activities include transfers of spat and live adult mussels between various geographic locations, which may result in large-scale changes in the world distribution of Mytilus taxa. Mytilus taxa are morphologically similar and difficult to distinguish. In spite of much research on taxonomy, evolution and geographic distribution, the native Mytilus taxa of the Southern Hemisphere are poorly understood. Recently, single nucleotide polymorphisms (SNPs) have been used to clarify the taxonomic status of populations of smooth shelled mussels from the Pacific coast of South America. In this paper, we used a set of SNPs to characterize, for the first time, populations of smooth shelled mussels Mytilus from the Atlantic coast of South America. Mytilus spp. samples were collected from eastern South America. Six reference samples from the Northern Hemisphere were used: Mytilus edulis from USA and Northern Ireland, Mytilus trossulus from Canada, and Mytilus galloprovincialis from Spain and Italy. Two other reference samples from the Southern Hemisphere were included: M. galloprovincialis from New Zealand and Mytilus chilensis from Chile. Fifty-five SNPs were successfully genotyped, of which 51 were polymorphic. Population genetic analyses using the STRUCTURE program revealed the clustering of eight populations from Argentina (Mytilus platensis) and the clustering of the sample from Ushuaia with M. chilensis from Chile. All individuals in the Puerto Madryn (Argentina) sample were identified as M. platensis × M. galloprovincialis F2 (88.89%) hybrids, except one that was classified as Mediterranean M. galloprovincialis. No F1 hybrids were observed. We demonstrate that M. platensis (or Mytilus edulis platensis) and M. chilensis are distinct native taxa in South America, which indicates that the evolutionary histories of Mytilus taxa along the

  4. Full genome sequences of zebra-borne equine herpesvirus type 1 isolated from zebra, onager and Thomson's gazelle.

    PubMed

    Guo, Xiaoqin; Izume, Satoko; Okada, Ayaka; Ohya, Kenji; Kimura, Takashi; Fukushi, Hideto

    2014-09-01

    A strain of equine herpesvirus type 1 (EHV-1) was isolated from zebra. This strain, called "zebra-borne EHV-1", was also isolated from an onager and a gazelle in zoological gardens in U.S.A. The full genome sequences of the 3 strains were determined. They shared 99% identities with each other, while they shared 98% and 95% identities with the horse derived EHV-1 and equine herpesvirus type 9, respectively. Sequence data indicated that the EHV-1 isolated from a polar bear in Germany is one of the zebra-borne EHV-1 and not a recombinant virus. These results indicated that zebra-borne EHV-1 is a subtype of EHV-1.

  5. Influence of parasitism in controlling the health, reproduction and PAH body burden of petroleum seep mussels

    NASA Astrophysics Data System (ADS)

    Powell, Eric N.; Barber, Robert D.; Kennicutt, Mahlon C., II; Ford, Susan E.

    1999-12-01

    Petroleum seep mussels are often exposed to high hydrocarbon concentrations in their natural habitat and, thus, offer the opportunity to examine the relationship between parasitism, disease and contaminant exposure under natural conditions. This is the first report on the histopathology of cold-seep mussels. Seep mussels were collected by submersible from four primary sites in the Gulf of Mexico, lease blocks Green Canyon (GC) 184, GC-234, GC-233, and Garden Banks 425 in 550-650 m water depth. Five types of parasites were identified in section: (1) gill "rosettes" of unknown affinity associated with the gill bacteriocytes, (2) gill "inclusions" similar to chlamydia/rickettsia inclusions, (3) extracellular gill ciliates, (4) body "inclusions" that also resemble chlamydial/rickettsial inclusions, and (5) Bucephalus-like trematodes. Comparison to shallow-water mytilids demonstrates that: (1) both have similar parasite faunas; (2) seep mytilids are relatively heavily parasitized; and (3) infection intensities are extremely high in comparison to shallow-water mytilids for Bucephalus and chlamydia/rickettsia. In this study, the lowest prevalence for chlamydia/rickettsia was 67%. Prevalences of 100% were recorded from three populations. Bucephalus prevalence was ⩾70% in three of 10 populations. The parasite fauna was highly variable between populations. Some important parasites were not observed in some primary sites. Even within primary sites, some important parasites were not observed in some populations. Bucephalus may exert a significant influence on seep mussel population dynamics. Forty percent of the populations in this study are severely reproductively compromised by Bucephalus infection. Only a fraction of petroleum seep mussel populations are maintaining the entire beta-level population structure of this species. Variation in two parasites, gill ciliates and Bucephalus, explained most of the variation in PAH body burden between mussel populations. PAHs are

  6. Laterality of suckling behaviour in three zebra species.

    PubMed

    Pluháček, Jan; Olléová, Michaela; Bartošová, Jitka; Pluháčková, Jana; Bartoš, Luděk

    2013-01-01

    Although side preference while suckling is an easily characterised lateralised behaviour, few studies have been conducted. We observed laterality in suckling behaviour in three captive zebra species to test two hypotheses: laterality affected by the foal (motor laterality) and laterality affected by the mother. In total we observed 35 foals of Grevy's, plains, and mountain zebra in two zoos and recorded 5128 successful suckling bouts and 9095 unsuccessful suckling attempts. At the population level the only factor affecting side preference of suckling bouts and attempts was the identity of the individual foal. Ten foals showed individual preferences: seven foals preferred suckling from the left side of the mother, three preferred suckling from the right side of the mother. The individual preferences increased with increasing age of the foal. Only one foal was refused more often from the opposite side than the preferred side used for suckling whereas three other foals were refused from the preferred side. Foals that preferred suckling either from left or right side were refused by the mare more often than foals which showed non-preference. Thus lateral preferences in suckling behaviour of zebra foals seem to be in line with the motor laterality hypotheses.

  7. Fitness consequences of polymorphic inversions in the zebra finch genome.

    PubMed

    Knief, Ulrich; Hemmrich-Stanisak, Georg; Wittig, Michael; Franke, Andre; Griffith, Simon C; Kempenaers, Bart; Forstmeier, Wolfgang

    2016-09-29

    Inversion polymorphisms constitute an evolutionary puzzle: they should increase embryo mortality in heterokaryotypic individuals but still they are widespread in some taxa. Some insect species have evolved mechanisms to reduce the cost of embryo mortality but humans have not. In birds, a detailed analysis is missing although intraspecific inversion polymorphisms are regarded as common. In Australian zebra finches (Taeniopygia guttata), two polymorphic inversions are known cytogenetically and we set out to detect these two and potentially additional inversions using genomic tools and study their effects on embryo mortality and other fitness-related and morphological traits. Using whole-genome SNP data, we screened 948 wild zebra finches for polymorphic inversions and describe four large (12-63 Mb) intraspecific inversion polymorphisms with allele frequencies close to 50 %. Using additional data from 5229 birds and 9764 eggs from wild and three captive zebra finch populations, we show that only the largest inversions increase embryo mortality in heterokaryotypic males, with surprisingly small effect sizes. We test for a heterozygote advantage on other fitness components but find no evidence for heterosis for any of the inversions. Yet, we find strong additive effects on several morphological traits. The mechanism that has carried the derived inversion haplotypes to such high allele frequencies remains elusive. It appears that selection has effectively minimized the costs associated with inversions in zebra finches. The highly skewed distribution of recombination events towards the chromosome ends in zebra finches and other estrildid species may function to minimize crossovers in the inverted regions.

  8. Effects of the pharmaceuticals gemfibrozil and diclofenac on biomarker expression in the zebra mussel (Dreissena polymorpha) and their comparison with standardised toxicity tests.

    PubMed

    Quinn, Brian; Schmidt, Wiebke; O'Rourke, Kathleen; Hernan, Robert

    2011-07-01

    Pharmaceuticals, including the lipid regulator gemfibrozil and the non-steroidal anti-inflammatory drug diclofenac have been identified in waste water treatment plant effluents and receiving waters throughout the western world. The acute and chronic toxicity of these compounds was assessed for three freshwater species (Daphnia magna, Pseudokirchneriella subcapitata, Lemna minor) using standardised toxicity tests with toxicity found in the non-environmentally relevant mid mg L(-1) concentration range. For the acute endpoints (IC(50) and EC(50)) gemfibrozil showed higher toxicity ranging from 29 to 59 mg L(-1) (diclofenac 47-67 mg L(-1)), while diclofenac was more toxic for the chronic D. magna 21 d endpoints ranging from 10 to 56 mg L(-1) (gemfibrozil 32-100 mg L(-1)). These results were compared with the expression of several biomarkers in the zebra mussel (Dreissena polymorpha) 24 and 96 h after exposure by injection to concentrations of 21 and 21,000 μg L(-1) corresponding to nominal concentrations of 1 and 1000 μg L(-1). Exposure to gemfibrozil and diclofenac at both concentrations significantly increased the level of lipid peroxidation, a biomarker of damage. At the elevated nominal concentration of 1000 μg L(-1) the biomarkers of defence glutathione transferase and metallothionein were significantly elevated for gemfibrozil and diclofenac respectively, as was DNA damage after 96 h exposure to gemfibrozil. No evidence of endocrine disruption was observed using the alkali-labile phosphate technique. Results from this suite of biomarkers indicate these compounds can cause significant stress at environmentally relevant concentrations acting primarily through oxidation pathways with significant destabilization of the lysosomal membrane and that biomarker expression is a more sensitive endpoint than standardised toxicity tests. Copyright © 2011 Elsevier Ltd. All rights reserved.

  9. Global Climate Change Interaction Web.

    ERIC Educational Resources Information Center

    Fortner, Rosanne W.

    1998-01-01

    Students investigate the effects of global climate change on life in the Great Lakes region in this activity. Teams working together construct as many links as possible for such factors as rainfall, lake water, evaporation, skiing, zebra mussels, wetlands, shipping, walleye, toxic chemicals, coastal homes, and population. (PVD)

  10. Polychlorinated naphthalenes and polychlorinated biphenyls in benthic organisms of a Great Lakes food chain.

    PubMed

    Hanari, N; Kannan, K; Horii, Y; Taniyasu, S; Yamashita, N; Jude, D J; Berg, M B

    2004-07-01

    Invasion of zebra mussels, Dreissena polymorpha, and round gobies, Neogobius melanostomus, into the Great Lakes has altered the food web structure and thereby the pathways of toxic contaminants such as polychlorinated biphenyls (PCBs) and polychlorinated naphthalenes (PCNs). In this study, concentrations of PCNs and PCBs were measured in organisms of a Great Lakes benthic food chain encompassing zebra mussels. PCNs were found in all of the benthic organisms, including phytoplankton, algae, amphipods, zebra mussels, round goby, and smallmouth bass, Micropterus dolomieui. Concentrations of PCNs were greater in samples collected from the Raisin River than in samples from the St. Clair River. Biomagnification factors (BMF) for tetra- through octa-CN congeners in going from algae to zebra mussels from the St. Clair River ranged from 3 to 10. No major biomagnification of PCNs was found in round gobies, when concentrations were related to those in their prey species, zebra mussels. The biomagnification potential of PCNs appears to be similar to that of PCBs in the benthic food chain investigated in this study, despite the fact that PCNs may be metabolized by organisms higher in the food chain. Among several congeners, the BMFs of PCN congeners 35, 42, 43/45, 52/60, 58, and 66/67 were highest in round gobies. PCNs accounted for 1-22% of the total TEQs (toxic equivalents) of PCBs and PCNs in benthic organisms analyzed in this study. PCB congener 126 was the major contributor to TEQs, accounting for 72-99% of the PCB-TEQs in the food chain organisms analyzed.

  11. Environmental Habitat Conditions Associated with Freshwater Dreissenids

    DTIC Science & Technology

    2010-12-01

    Figure 1. Important biological effects of temperature on dreissenids. Temperature effects . Ambient temperature regulates metabolic rate in...is often reported separately because of its effect on osmoregulation and shell formation in zebra mussels (Vinogradov et al. 1993; McMahon 1996...Ramcharan et al. 1992; Mellina and Rasmussen 1994). As with pH, zebra mussels demonstrate less effective osmoregulation at moderate or low pH levels than

  12. RELATIONSHIPS AMONG TOTAL LIPID, LIPID CLASSES AND POLYCHLORINATED BIPHENYL CONCENTRATIONS IN TWO INDIGENOUS POPULATIONS OF RIBBED MUSSELS (GUKENSIA DEMISSA) OVER AN ANNUAL CYCLE

    EPA Science Inventory

    Two indigenous ribbed mussel (Geukensia demissa) populations were sampled approximately every four weeks during 1997 to investigate the relationships among concentrations of total lipid, lipid classes, and polychlorinated biphenyls (PCBs). One population was located in a highly c...

  13. Zebra: A striped network file system

    NASA Technical Reports Server (NTRS)

    Hartman, John H.; Ousterhout, John K.

    1992-01-01

    The design of Zebra, a striped network file system, is presented. Zebra applies ideas from log-structured file system (LFS) and RAID research to network file systems, resulting in a network file system that has scalable performance, uses its servers efficiently even when its applications are using small files, and provides high availability. Zebra stripes file data across multiple servers, so that the file transfer rate is not limited by the performance of a single server. High availability is achieved by maintaining parity information for the file system. If a server fails its contents can be reconstructed using the contents of the remaining servers and the parity information. Zebra differs from existing striped file systems in the way it stripes file data: Zebra does not stripe on a per-file basis; instead it stripes the stream of bytes written by each client. Clients write to the servers in units called stripe fragments, which are analogous to segments in an LFS. Stripe fragments contain file blocks that were written recently, without regard to which file they belong. This method of striping has numerous advantages over per-file striping, including increased server efficiency, efficient parity computation, and elimination of parity update.

  14. Ecotoxicological impact of Zequanox®, a novel biocide, on selected non-target Irish aquatic species.

    PubMed

    Meehan, Sara; Shannon, Adam; Gruber, Bridget; Rackl, Sarahann M; Lucy, Frances E

    2014-09-01

    Effective, species-specific zebra mussel control is needed urgently for Ireland׳s freshwater bodies, which became infested with non-native zebra mussels in the 1990s. Zequanox®, a newly commercialized product for zebra and quagga mussel control, is composed of dead Pseudomonas fluorescens CL 145A cells. This paper describes ecotoxicology tests on three representative native Irish freshwater species: Anodonta (duck mussel), Chironomus plumosus (non-biting midge), and Austropotamobius pallipes (white-clawed crayfish). The species were exposed to Zequanox in a 72-h static renewal toxicity test at concentrations of 100-750mg active ingredient per liter (mga.i./L). Water quality parameters were measured every 12-24h before and after water and product renewal. After 72h, endpoints were reported as LC10, LC50, and LC100. The LC50 values derived were (1) Anodonta: ≥500mga.i./L (2) C. plumosus: 1075mga.i./L, and (3) A. pallipes: ≥750mga.i./L. These results demonstrate that Zequanox does not negatively affect these organisms at the concentration required for >80percent zebra mussel mortality (150mg a.i/L) and the maximum allowable treatment concentration in the United Sates (200mga.i./L). They also show the overall species-specificity of Zequanox, and support its use in commercial facilities and open waters. Copyright © 2014 Elsevier Inc. All rights reserved.

  15. Lake whitefish diet, condition, and energy density in Lake Champlain and the lower four Great Lakes following dreissenid invasions

    USGS Publications Warehouse

    Herbst, Seth J.; Marsden, J. Ellen; Lantry, Brian F.

    2013-01-01

    Lake Whitefish Coregonus clupeaformis support some of the most valuable commercial freshwater fisheries in North America. Recent growth and condition decreases in Lake Whitefish populations in the Great Lakes have been attributed to the invasion of the dreissenid mussels, zebra mussels Dreissena polymorpha and quagga mussels D. bugensis, and the subsequent collapse of the amphipod, Diporeia, a once-abundant high energy prey source. Since 1993, Lake Champlain has also experienced the invasion and proliferation of zebra mussels, but in contrast to the Great Lakes, Diporeia were not historically abundant. We compared the diet, condition, and energy density of Lake Whitefish from Lake Champlain after the dreissenid mussel invasion to values for those of Lake Whitefish from Lakes Michigan, Huron, Erie, and Ontario. Lake Whitefish were collected using gill nets and bottom trawls, and their diets were quantified seasonally. Condition was estimated using Fulton's condition factor (K) and by determining energy density. In contrast to Lake Whitefish from some of the Great Lakes, those from Lake Champlain Lake Whitefish did not show a dietary shift towards dreissenid mussels, but instead fed primarily on fish eggs in spring, Mysis diluviana in summer, and gastropods and sphaeriids in fall and winter. Along with these dietary differences, the condition and energy density of Lake Whitefish from Lake Champlain were high compared with those of Lake Whitefish from Lakes Michigan, Huron, and Ontario after the dreissenid invasion, and were similar to Lake Whitefish from Lake Erie; fish from Lakes Michigan, Huron, and Ontario consumed dreissenids, whereas fish from Lake Erie did not. Our comparisons of Lake Whitefish populations in Lake Champlain to those in the Great Lakes indicate that diet and condition of Lake Champlain Lake Whitefish were not negatively affected by the dreissenid mussel invasion.

  16. A Probability Co-Kriging Model to Account for Reporting Bias and Recognize Areas at High Risk for Zebra Mussels and Eurasian Watermilfoil Invasions in Minnesota

    PubMed Central

    Kanankege, Kaushi S. T.; Alkhamis, Moh A.; Phelps, Nicholas B. D.; Perez, Andres M.

    2018-01-01

    Zebra mussels (ZMs) (Dreissena polymorpha) and Eurasian watermilfoil (EWM) (Myriophyllum spicatum) are aggressive aquatic invasive species posing a conservation burden on Minnesota. Recognizing areas at high risk for invasion is a prerequisite for the implementation of risk-based prevention and mitigation management strategies. The early detection of invasion has been challenging, due in part to the imperfect observation process of invasions including the absence of a surveillance program, reliance on public reporting, and limited resource availability, which results in reporting bias. To predict the areas at high risk for invasions, while accounting for underreporting, we combined network analysis and probability co-kriging to estimate the risk of ZM and EWM invasions. We used network analysis to generate a waterbody-specific variable representing boater traffic, a known high risk activity for human-mediated transportation of invasive species. In addition, co-kriging was used to estimate the probability of species introduction, using waterbody-specific variables. A co-kriging model containing distance to the nearest ZM infested location, boater traffic, and road access was used to recognize the areas at high risk for ZM invasions (AUC = 0.78). The EWM co-kriging model included distance to the nearest EWM infested location, boater traffic, and connectivity to infested waterbodies (AUC = 0.76). Results suggested that, by 2015, nearly 20% of the waterbodies in Minnesota were at high risk of ZM (12.45%) or EWM (12.43%) invasions, whereas only 125/18,411 (0.67%) and 304/18,411 (1.65%) are currently infested, respectively. Prediction methods presented here can support decisions related to solving the problems of imperfect detection, which subsequently improve the early detection of biological invasions. PMID:29354638

  17. Zebra Alphaherpesviruses (EHV-1 and EHV-9): Genetic Diversity, Latency and Co-Infections.

    PubMed

    Abdelgawad, Azza; Damiani, Armando; Ho, Simon Y W; Strauss, Günter; Szentiks, Claudia A; East, Marion L; Osterrieder, Nikolaus; Greenwood, Alex D

    2016-09-20

    Alphaherpesviruses are highly prevalent in equine populations and co-infections with more than one of these viruses' strains frequently diagnosed. Lytic replication and latency with subsequent reactivation, along with new episodes of disease, can be influenced by genetic diversity generated by spontaneous mutation and recombination. Latency enhances virus survival by providing an epidemiological strategy for long-term maintenance of divergent strains in animal populations. The alphaherpesviruses equine herpesvirus 1 (EHV-1) and 9 (EHV-9) have recently been shown to cross species barriers, including a recombinant EHV-1 observed in fatal infections of a polar bear and Asian rhinoceros. Little is known about the latency and genetic diversity of EHV-1 and EHV-9, especially among zoo and wild equids. Here, we report evidence of limited genetic diversity in EHV-9 in zebras, whereas there is substantial genetic variability in EHV-1. We demonstrate that zebras can be lytically and latently infected with both viruses concurrently. Such a co-occurrence of infection in zebras suggests that even relatively slow-evolving viruses such as equine herpesviruses have the potential to diversify rapidly by recombination. This has potential consequences for the diagnosis of these viruses and their management in wild and captive equid populations.

  18. An individual-based population dynamic model for estimating biomass yield and nutrient fluxes through an off-shore mussel ( Mytilus galloprovincialis) farm

    NASA Astrophysics Data System (ADS)

    Brigolin, Daniele; Maschio, Gabriele Dal; Rampazzo, Federico; Giani, Michele; Pastres, Roberto

    2009-04-01

    The fluxes of carbon, nitrogen and phosphorus through an off-shore long-line Mytilus galloprovincialis farm during a typical rearing cycle were estimated by combining a simple population dynamic model, based on a new individual model, and a set of field data, concerning the composition of the seston, as well as that of mussel meat and faeces. The individual model, based on an energy budget, was validated against a set of original field data, which were purposely collected from July 2006 to May 2007 in the North-Western Adriatic Sea (Italy) and was further tested using historical data. The model was upscaled to the population level by means of a set of Monte Carlo simulations, which were used for estimating the size structure of the population. The daily fluxes of C, N and P associated with mussel filtration, excretion and faeces and pseudo-faeces production were integrated over the 10-month-long rearing cycle and compared with the total amount of C, N and P removed by harvesting. The results indicate that the individual model compares well with an existing literature model and provides reliable estimations of the growth of mussel specimen over a range of trophic conditions which are typical of the Northern Adriatic Sea coastal area. The results of the budget calculation indicate that, even though the harvest represents a net removal of phosphorus and nitrogen from the ecosystem, the mussel farm increases the retention time of both nutrients in the coastal area, via the deposition of faeces and pseudo-faeces on the sea-bed. In fact, the amount of nitrogen associated with deposition is approximately twice the harvested one and the amount of phosphorus is approximately five times higher. These findings are in qualitative agreement with the results of literature budget and model calculations carried out in a temperate coastal embayment. This agreement suggests that the proper assessment of the overall effect of long-line mussel farming on both the benthic and pelagic

  19. Water quality, sediment characteristics, aquatic habitat, geomorphology, and mussel population status of the Clinch River, Virginia and Tennessee, 2009-2011

    USGS Publications Warehouse

    Krstolic, Jennifer L.; Johnson, Gregory C.; Ostby, Brett J.K.

    2013-01-01

    Chemical, physical, and biological data were collected during 2009-2011 as part of a study of the Clinch River in Virginia and Tennessee. The data from this study, data-collection methods, and laboratory analytical methods used in the study are documented in this report. The study was conducted to describe the conditions of the Clinch River and to determine if there are measurable differences in chemical, physical, or biological characteristics in a segment of the river where freshwater mussel populations are in decline, have low density, richness, little to no recruitment, and lack endangered species (low-quality reach) compared to a segment of the river where mussel assemblages have relatively high density, richness, evidence of recruitment, and support endangered species (high-quality reach). Five continuous water-quality monitors were installed and operated on the mainstem of the Clinch River and two tributaries. Discrete water-quality sample sets were collected during base-flow and stormflow conditions two sites on the Clinch River and on the Guest River, a tributary to the Clinch River predominantly in the Appalachian Plateaus Physiographic Province. Base-flow water-quality samples were collected in July and August 2011 at 15 sites along the mainstem of the Clinch River. Other analyses included longitudinal sampling along the mainstem of the Clinch River at 10 sites to evaluate bed-sediment chemistry, habitat condition, and mollusk community status. In situ freshwater mussel growth and mortality experiments were conducted with hatchery propogated Villosa iris (rainbow mussels). Tissue from the V. iris as well as tissue from 16 Actinonaias pectorosa mussels were analyzed for trace metals, and V. iris mussel tissue was analyzed for organic compounds. Data collected during this investigation were analyzed by various U.S. Geological Survey or U.S. Fish and Wildlife Service laboratories.

  20. The role of habitat-selection in restricting invasive blue mussel advancement to protect native populations in San Francisco Bay

    NASA Astrophysics Data System (ADS)

    Mittal, N.; Saarman, N. P.; Pogson, G.

    2013-12-01

    Introduced species contribute to decline of biodiversity and ecosystem services. Introduced species threaten native species by increasing competition for space and resources, changing their habitat, and disrupting species interactions. Protecting native species is crucial to preserving ecosystem services (i.e. medicinal, agricultural, ecological, and cultural benefits) for future generations. In marine communities, the number of invasive species is dramatically increasing every year, further magnifying the negative impact on native species. This research determines if habitat-specific selection can protect native species from their invasive relatives, and could allow targeted habitat restoration for native species to maintain high levels of biodiversity. Blue mussels provide an ideal system for studying the impact of an invasive species (Mytilus galloprovincialis) on native mussels (M. trossulus), because M. galloprovincialis is marked as one of the world's 100 worst invasive species. Hybridization between M. galloprovincialis and M. trossulus occurs wherever their distributions overlap (i.e. Japan, Puget Sound, and central California). In central California, hybrids form in a broad variety of habitats ever since M. galloprovincialis was introduced about 100 years ago. The current level of threat posed to native mussels in central California is unknown. When population growth rate of an invasive species is higher than the native within a hybrid zone, the invader's genes become more prominent in the hybrids than the native species' genes. This uneven mix of genes and decrease of pure native mussels threatens to drive M. trossulus to extinction. Therefore, it is important to research which environment fosters highest success of pure native species. We conducted a field experiment in San Francisco Bay where mussels were reared in different habitats. We then collected samples and extracted DNA from each treatment, and genotyped them by a next-generation sequencing

  1. Exposure of unionid mussels to electric current: Assessing risks associated with electrofishing

    USGS Publications Warehouse

    Holliman, F.M.; Kwak, T.J.; Cope, W.G.; Levine, Jay F.

    2007-01-01

    Electric current is routinely applied in freshwater for scientific sampling of fish populations (i.e., electrofishing). Freshwater mussels (families Margaritiferidae and Unionidae) are distributed worldwide, but their recent declines in diversity and abundance constitute an imperilment of global significance. Freshwater mussels are not targeted for capture by electrofishing, and any exposure to electric current is unintentional. The effects of electric shock are not fully understood for mussels but could disrupt vital physiological processes and represent an additional threat to their survival. In a controlled laboratory environment, we examined the consequences of exposure to two typical electrofishing currents, 60-Hz pulsed DC and 60-Hz AC, for the survival of adult and early life stages of three unionid species; we included fish as a quality control measure. The outcomes suggest that electrical exposure associated with typical electrofishing poses little direct risk to freshwater mussels. That is, adult mussel survival and righting behaviors (indicators of sublethal stress) were not adversely affected by electrical exposure. Glochidia (larvae that attach to and become parasites on fish gills or fins) showed minimal immediate reduction in viability after exposure. Metamorphosis from glochidia to free-living juvenile mussels was not impaired after electric current simulated capture-prone behaviors (stunning) in infested host fish. In addition, the short-term survival of juvenile mussels was not adversely influenced by exposure to electric current. Any minimal risk to imperiled mussels must be weighed at the population level against the benefits gained by using the gear for scientific sampling of fish in the same waters. However, scientists sampling fish by electrofishing should be aware of mussel reproductive periods and processes in order to minimize the harmful effects to host fish, especially in areas where mussel conservation is a concern. ?? Copyright by the

  2. Simulated mussel mortality thresholds as a function of mussel biomass and nutrient loading

    USGS Publications Warehouse

    Bril, Jeremy S.; Langenfeld, Kathryn; Just, Craig L.; Spak, Scott N.; Newton, Teresa

    2017-01-01

    A freshwater “mussel mortality threshold” was explored as a function of porewater ammonium (NH4+) concentration, mussel biomass, and total nitrogen (N) utilizing a numerical model calibrated with data from mesocosms with and without mussels. A mortality threshold of 2 mg-N L−1 porewater NH4+ was selected based on a study that estimated 100% mortality of juvenile Lampsilis mussels exposed to 1.9 mg-N L−1NH4+ in equilibrium with 0.18 mg-N L−1 NH3. At the highest simulated mussel biomass (560 g m−2) and the lowest simulated influent water “food” concentration (0.1 mg-N L−1), the porewater NH4+ concentration after a 2,160 h timespan without mussels was 0.5 mg-N L−1 compared to 2.25 mg-N L−1 with mussels. Continuing these simulations while varying mussel biomass and N content yielded a mortality threshold contour that was essentially linear which contradicted the non-linear and non-monotonic relationship suggested by Strayer (2014). Our model suggests that mussels spatially focus nutrients from the overlying water to the sediments as evidenced by elevated porewater NH4+ in mesocosms with mussels. However, our previous work and the model utilized here show elevated concentrations of nitrite and nitrate in overlying waters as an indirect consequence of mussel activity. Even when the simulated overlying water food availability was quite low, the mortality threshold was reached at a mussel biomass of about 480 g m−2. At a food concentration of 10 mg-N L−1, the mortality threshold was reached at a biomass of about 250 g m−2. Our model suggests the mortality threshold for juvenile Lampsilis species could be exceeded at low mussel biomass if exposed for even a short time to the highly elevated total N loadings endemic to the agricultural Midwest.

  3. Zebras and Biting Flies: Quantitative Analysis of Reflected Light from Zebra Coats in Their Natural Habitat

    PubMed Central

    Britten, Kenneth H.; Thatcher, Timothy D.; Caro, Tim

    2016-01-01

    Experimental and comparative evidence suggests that the striped coats of zebras deter biting fly attack, but the mechanisms by which flies fail to target black-and-white mammals are still opaque. Two hypotheses have been proposed: stripes might serve either to defeat polarotaxis or to obscure the form of the animal. To test these hypotheses, we systematically photographed free-living plains zebras in Africa. We found that black and white stripes both have moderate polarization signatures with a similar angle, though the degree (magnitude) of polarization in white stripes is lower. When we modeled the visibility of these signals from different distances, we found that polarization differences between stripes are invisible to flies more than 10 m away because they are averaged out by the flies’ low visual resolution. At any distance, however, a positively polarotactic insect would have a distinct signal to guide its visual approach to a zebra because we found that polarization of light reflecting from zebras is higher than from surrounding dry grasses. We also found that the stripes themselves are visible to flies at somewhat greater distances (up to 20 m) than the polarization contrast between stripes. Together, these observations support hypotheses in which zebra stripes defeat visually guided orienting behavior in flies by a mechanism independent of polarotaxis. PMID:27223616

  4. Macrofouling control in nuclear power plants

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Ekis, E.W. Jr.; Keoplin-Gall, S.M.; McCarthy, R.E.

    1991-11-01

    Macrofouling of cooling-water systems is one of the more significant and costly problems encountered in the nuclear power industry. Both marine and freshwater macroinvertebrates can be responsible for losses in plant availability because of plugged intakes and heat transfer equipment. There is a greater diversity of macrofouling organisms in marine waters than in fresh waters. Marine macrofouling organisms include barnacles, mollusks, bryozoans, and hydroids. Barnacles are crustaceans with feathery appendages, which allow them to attach to a variety of surfaces. They are a major cause of severe macrofouling because they can remain attached even after death. The major freshwater macrofoulingmore » organisms include the Asiatic Clam (Corbicula fluminea) and the newest freshwater macrofouler, the Zebra Mussel (Dreissena polymorpha). The introduction of the Zebra Mussel into the Great Lakes has created economic and ecological problems that will not easily be solved. The threat of intercontinental dispersal of the Zebra Mussel in America is serious. Research programs have been initiated around the country to develop control methods for this macrofouling problem. The various control methodologies can be classified in the following categories: biological, chemical, physical, and mechanical. Laboratory experiments were performed to evaluate the efficacy of Actibrom against mature Zebra Mussels.« less

  5. Early invasion population structure of quagga mussel and associated benthic invertebrate community composition on soft sediment in a large reservoir

    USGS Publications Warehouse

    Wittmann, Marion E.; Chandra, Sudeep; Caires, Andrea; Denton, Marianne; Rosen, Michael R.; Wong, Wai Hing; Teitjen, Todd; Turner, Kent; Roefer, Peggy; Holdren, G. Chris

    2010-01-01

    In 2007 an invasive dreissenid mussel species, Dreissena bugensis (quagga mussel), was discovered in Lake Mead reservoir (AZ–NV). Within 2 years, adult populations have spread throughout the lake and are not only colonizing hard substrates, but also establishing in soft sediments at depths ranging from 1 to >100 m. Dreissena bugensis size class and population density distribution differs between basins; cluster analysis revealed 5 adult cohorts within Boulder Basin and Overton Arm but low densities and low cohort survival in the Las Vegas Basin. Regression analysis suggests depth and temperature are not primary controllers of D. bugensis density in Lake Mead, indicating other factors such as sediment type, food availability or other resource competition may be important. Monthly veliger tows showed at least 2 major spawning events per year, with continuous presence of veligers in the water column. Adult mussels have been found in spawn or post-spawn condition in soft sediments in shallow to deep waters (>80 m) indicating the potential for reproduction at multiple depths. Comparisons to a 1986 benthic survey suggest there have been shifts in nondreissenid macroinvertebrate composition; however, it is unclear if this is due to D. bugensis presence. Current distribution of nondreissenid macroinvertebrates is heterogeneous in all 3 basins, and their biodiversity decreased when D. bugensis density was 2500/m2 or greater.

  6. Uncovering the Complex Transcriptome Response of Mytilus chilensis against Saxitoxin: Implications of Harmful Algal Blooms on Mussel Populations.

    PubMed

    Detree, Camille; Núñez-Acuña, Gustavo; Roberts, Steven; Gallardo-Escárate, Cristian

    2016-01-01

    Saxitoxin (STX), a principal phycotoxin contributing to paralytic shellfish poisoning, is largely produced by marine microalgae of the genus Alexandrium. This toxin affects a wide range of species, inducing massive deaths in fish and other marine species. However, marine bivalves can resist and accumulate paralytic shellfish poisons. Despite numerous studies on the impact of STX in marine bivalves, knowledge regarding STX recognition at molecular level by benthic species remains scarce. Therefore, the aim of this study was to identify novel genes that interact with STX in the Chilean mussel Mytilus chilensis. For this, RNA-seq and RT-qPCR approaches were used to evaluate the transcriptomic response of M. chilensis to a purified STX as well as in vivo Alexandrium catenella exposure. Approximately 800 million reads were assembled, generating 138,883 contigs that were blasted against the UniProt Mollusca database. Pattern Recognition Receptors (PRRs) involved in mussel immunity, such as Toll-like receptors, tumor necrosis factor receptors, and scavenger-like receptors were found to be strongly upregulated at 8 and 16 h post-STX injection. These results suggest an involvement of PRRs in the response to STX, as well as identifying potential, novel STX-interacting receptors in this Chilean mussel. This study is the first transcriptomic overview of the STX-response in the edible species M. chilensis. However, the most significant contribution of this work is the identification of immune receptors and pathways potentially involved in the recognition and defense against STX's toxicity and its impact of harmful algae blooms on wild and cultivated mussel populations.

  7. Uncovering the Complex Transcriptome Response of Mytilus chilensis against Saxitoxin: Implications of Harmful Algal Blooms on Mussel Populations

    PubMed Central

    Detree, Camille; Núñez-Acuña, Gustavo; Roberts, Steven; Gallardo-Escárate, Cristian

    2016-01-01

    Saxitoxin (STX), a principal phycotoxin contributing to paralytic shellfish poisoning, is largely produced by marine microalgae of the genus Alexandrium. This toxin affects a wide range of species, inducing massive deaths in fish and other marine species. However, marine bivalves can resist and accumulate paralytic shellfish poisons. Despite numerous studies on the impact of STX in marine bivalves, knowledge regarding STX recognition at molecular level by benthic species remains scarce. Therefore, the aim of this study was to identify novel genes that interact with STX in the Chilean mussel Mytilus chilensis. For this, RNA-seq and RT-qPCR approaches were used to evaluate the transcriptomic response of M. chilensis to a purified STX as well as in vivo Alexandrium catenella exposure. Approximately 800 million reads were assembled, generating 138,883 contigs that were blasted against the UniProt Mollusca database. Pattern Recognition Receptors (PRRs) involved in mussel immunity, such as Toll-like receptors, tumor necrosis factor receptors, and scavenger-like receptors were found to be strongly upregulated at 8 and 16 h post-STX injection. These results suggest an involvement of PRRs in the response to STX, as well as identifying potential, novel STX-interacting receptors in this Chilean mussel. This study is the first transcriptomic overview of the STX-response in the edible species M. chilensis. However, the most significant contribution of this work is the identification of immune receptors and pathways potentially involved in the recognition and defense against STX’s toxicity and its impact of harmful algae blooms on wild and cultivated mussel populations. PMID:27764234

  8. DOE Office of Scientific and Technical Information (OSTI.GOV)

    Daniel Molloy

    Under this USDOE-NETL contract, the bacterium Pseudomonas fluorescens is being developed as a biocontrol agent for zebra mussels. The specific purpose of the contract is to identify biotic and abiotic factors that affect mussel kill. Ingestion of these bacteria by zebra mussels is required to achieve kill, and tests evaluating factors that relate to mussel feeding are contained in this report. Specifically the impact of the following two factors were investigated: (1) Mussel siphoning behavior--In nature, zebra mussels typically have their two shells spread apart and their inhalant siphon tube extended from between their shells for taking food particles intomore » their mantle cavities (Fig. 1). Our tests indicated that there is a direct correlation between mussel siphoning activity and mussel mortality achieved by a bacterial treatment. Therefore, to encourage mussel feeding on bacteria, future pipe treatments within power plants should be carried out using procedures which minimize disturbance to mussel siphoning. 2. Naturally suspended particle loads--Since bacterial cells are lethal only if ingested by mussels, waters containing very high levels of naturally suspended particles might reduce the mortality that can be achieved by a bacterial treatment. If true, this inhibition might occur as a result of particle exclusion, i.e., there could be reduced ingestion of bacterial cells since they represent a reduced percentage of all particles ingested. Our tests indicated that a range of particle concentrations that might naturally exist in a turbid river did not inhibit mussel kill by the bacterial cells, but that an artificially high load of natural particles was capable of causing a reduction in kill. To be conservative, therefore, future pipe treatments should be timed to occur when intake waters have relatively low quantities of naturally suspended particulate matter.« less

  9. Micro-scale environmental variation amplifies physiological variation among individual mussels.

    PubMed

    Jimenez, Ana Gabriela; Jayawardene, Sarah; Alves, Shaina; Dallmer, Jeremiah; Dowd, W Wesley

    2015-12-07

    The contributions of temporal and spatial environmental variation to physiological variation remain poorly resolved. Rocky intertidal zone populations are subjected to thermal variation over the tidal cycle, superimposed with micro-scale variation in individuals' body temperatures. Using the sea mussel (Mytilus californianus), we assessed the consequences of this micro-scale environmental variation for physiological variation among individuals, first by examining the latter in field-acclimatized animals, second by abolishing micro-scale environmental variation via common garden acclimation, and third by restoring this variation using a reciprocal outplant approach. Common garden acclimation reduced the magnitude of variation in tissue-level antioxidant capacities by approximately 30% among mussels from a wave-protected (warm) site, but it had no effect on antioxidant variation among mussels from a wave-exposed (cool) site. The field-acclimatized level of antioxidant variation was restored only when protected-site mussels were outplanted to a high, thermally stressful site. Variation in organismal oxygen consumption rates reflected antioxidant patterns, decreasing dramatically among protected-site mussels after common gardening. These results suggest a highly plastic relationship between individuals' genotypes and their physiological phenotypes that depends on recent environmental experience. Corresponding context-dependent changes in the physiological mean-variance relationships within populations complicate prediction of responses to shifts in environmental variability that are anticipated with global change. © 2015 The Author(s).

  10. Fluvial processes and local lithology controlling abundance, structure, and composition of mussel beds.

    PubMed

    Vannote, R L; Minshall, G W

    1982-07-01

    In the Salmon River Canyon, Idaho, the fresh-water pearl mussel, Margaritifera falcata, attains maximum density and age in river reaches where large block-boulders structurally stabilize cobbles and interstitial gravels. We hypothesize that block-boulders prevent significant bed scour during major floods, and these boulder-sheltered mussel beds, although rare, may be critical for population recruitment elsewhere within the river, especially after periodic flood scour of less protected mussel habitat. Mussel shells in Indian middens adjacent to these boulder-stabilized areas suggest that prehistoric tribes selectively exploited the high-density old-aged mussel beds. Locally, canyon reaches are aggrading with sand and gravel, and M. falcata is being replaced by Gonidea angulata.

  11. Species traits and catchment-scale habitat factors influence the occurrence of freshwater mussel populations and assemblages

    USGS Publications Warehouse

    Pandolfo, Tamara J.; Kwak, Thomas J.; Cope, W. Gregory; Heise, Ryan J.; Nichols, Robert B.; Pacifici, Krishna

    2016-01-01

    Conservation of freshwater unionid mussels presents unique challenges due to their distinctive life cycle, cryptic occurrence and imperilled status. Relevant ecological information is urgently needed to guide their management and conservation.We adopted a modelling approach, which is a novel application to freshwater mussels to enhance inference on rare species, by borrowing data among species in a hierarchical framework to conduct the most comprehensive occurrence analysis for freshwater mussels to date. We incorporated imperfect detection to more accurately examine effects of biotic and abiotic factors at multiple scales on the occurrence of 14 mussel species and the entire assemblage of the Tar River Basin of North Carolina, U.S.A.The single assemblage estimate of detection probability for all species was 0.42 (95% CI, 0.36–0.47) with no species- or site-specific detection effects identified. We empirically observed 15 mussel species in the basin but estimated total species richness at 21 (95% CI, 16–24) when accounting for imperfect detection.Mean occurrence probability among species ranged from 0.04 (95% CI, 0.01–0.16) for Alasmidonta undulata, an undescribed Lampsilis sp., and Strophitus undulatus to 0.67 (95% CI, 0.42–0.86) for Elliptio icterina. Median occurrence probability among sites was <0.30 for all species with the exception of E. icterina. Site occurrence probability generally related to mussel conservation status, with reduced occurrence for endangered and threatened species.Catchment-scale abiotic variables (stream power, agricultural land use) and species traits (brood time, host specificity, tribe) influenced the occurrence of mussel assemblages more than reach- or microhabitat-scale features.Our findings reflect the complexity of mussel ecology and indicate that habitat restoration alone may not be adequate for mussel conservation. Catchment-scale management can benefit an entire assemblage, but species-specific strategies may be

  12. Detection of Cryptosporidium oocysts in green mussels (Perna viridis) from shell-fish markets of Thailand.

    PubMed

    Srisuphanunt, M; Wiwanitkit, Viroj; Saksirisampant, W; Karanis, P

    2009-09-01

    Mussels filter large volumes of water and can concentrate pathogenic organisms, which may act as potential vehicles of transmission to the consumer. A survey study was carried out to investigate the presence of Cryptosporidium protozoan parasites in green mussels (Perna viridis), the smussles pecies most destined for consumption in Thailand. In total, 56 samples were examined from Bangkok (n = 24) and Samut Prakan (n = 32) a wholesale shell-fish markets located at the mouth of the Chao Phraya River. The market for green mussels was closed to the mussel culture placed along the coastal line and this localization may have significant economical impact if the mussels' cultures are found contaminated. Cryptosporidium spp. oocysts were detected by the immunofluorescence antibody method (IFA) in 12.5% of the samples examined. The detection of Cryptosporidium oocysts in green mussels' population of Samut Prakan was higher (15.6%) than in Bangkok market (8.3%). These differences in positive samples from the two locations may be caused by physical, ecological and anthropogenic conditions. This could relay to different contamination levels of marine water by Cryptosporidium oocysts and consequently to contamination of harvested shellfish populations. The results demonstrate that the Cryptosporidium spp. oocysts were found indigenous in mussels from the coastal line of Thailand, indicating that mussels may act as a reservoir of Cryptosporidium foodborne infections for humans.

  13. Understanding Marine Mussel Adhesion

    PubMed Central

    Roberto, Francisco F.

    2007-01-01

    In addition to identifying the proteins that have a role in underwater adhesion by marine mussels, research efforts have focused on identifying the genes responsible for the adhesive proteins, environmental factors that may influence protein production, and strategies for producing natural adhesives similar to the native mussel adhesive proteins. The production-scale availability of recombinant mussel adhesive proteins will enable researchers to formulate adhesives that are water-impervious and ecologically safe and can bind materials ranging from glass, plastics, metals, and wood to materials, such as bone or teeth, biological organisms, and other chemicals or molecules. Unfortunately, as of yet scientists have been unable to duplicate the processes that marine mussels use to create adhesive structures. This study provides a background on adhesive proteins identified in the blue mussel, Mytilus edulis, and introduces our research interests and discusses the future for continued research related to mussel adhesion. PMID:17990038

  14. Threats of habitat and water-quality degradation to mussel diversity in the Meramec River Basin, Missouri, USA

    USGS Publications Warehouse

    Hinck, Jo Ellen; Ingersoll, Christopher G.; Wang, Ning; Augspurger, Tom; Barnhart, M. Christopher; McMurray, Stephen E.; Roberts, Andrew D.; Schrader, Lynn

    2011-01-01

    The Meramec River Basin in east-central Missouri is an important stronghold for native freshwater mussels (Order: Unionoida) in the United States. Whereas the basin supports more than 40 mussel species, previous studies indicate that the abundance and distribution of most species are declining. Therefore, resource managers have identified the need to prioritize threats to native mussel populations in the basin and to design a mussel monitoring program. The objective of this study was to identify threats of habitat and water-quality degradation to mussel diversity in the basin. Affected habitat parameters considered as the main threats to mussel conservation included excess sedimentation, altered stream geomorphology and flow, effects on riparian vegetation and condition, impoundments, and invasive non-native species. Evaluating water-quality parameters for conserving mussels was a main focus of this study. Mussel toxicity data for chemical contaminants were compared to national water quality criteria (NWQC) and Missouri water quality standards (MWQS). However, NWQC and MWQS have not been developed for many chemical contaminants and some MWQS may not be protective of native mussel populations. Toxicity data indicated that mussels are sensitive to ammonia, copper, temperature, certain pesticides, pharmaceuticals, and personal care products; these compounds were identified as the priority water-quality parameters for mussel conservation in the basin. Measures to conserve mussel diversity in the basin include expanding the species and life stages of mussels and the list of chemical contaminants that have been assessed, establishing a long term mussel monitoring program that measures physical and chemical parameters of high priority, conducting landscape scale modeling to predict mussel distributions, determining sublethal effects of primary contaminants of concern, deriving risk-based guidance values for mussel conservation, and assessing the effects of wastewater

  15. Dynamics of the Lake Michigan food web, 1970-2000

    USGS Publications Warehouse

    Madenjian, Charles P.; Fahnenstiel, Gary L.; Johengen, Thomas H.; Nalepa, Thomas F.; Vanderploeg, Henry A.; Fleischer, Guy W.; Schneeberger, Philip J.; Benjamin, Darren M.; Smith, Emily B.; Bence, James R.; Rutherford, Edward S.; Lavis, Dennis S.; Robertson, Dale M.; Jude, David J.; Ebener, Mark P.

    2002-01-01

    Herein, we document changes in the Lake Michigan food web between 1970 and 2000 and identify the factors responsible for these changes. Control of sea lamprey (Petromyzon marinus) and alewife (Alosa pseudoharengus) populations in Lake Michigan, beginning in the 1950s and 1960s, had profound effects on the food web. Recoveries of lake whitefish (Coregonus clupeaformis) and burbot (Lota lota) populations, as well as the buildup of salmonine populations, were attributable, at least in part, to sea lamprey control. Based on our analyses, predation by salmonines was primarily responsible for the reduction in alewife abundance during the 1970s and early 1980s. In turn, the decrease in alewife abundance likely contributed to recoveries of deepwater sculpin (Myoxocephalus thompsoni), yellow perch (Perca flavescens), and burbot populations during the 1970s and 1980s. Decrease in the abundance of all three dominant benthic macroinvertebrate groups, including Diporeia, oligochaetes, and sphaeriids, during the 1980s in nearshore waters (50 m deep) of Lake Michigan, was attributable to a decrease in primary production linked to a decline in phosphorus loadings. Continued decrease in Diporeia abundance during the 1990s was associated with the zebra mussel (Dreissena polymorpha) invasion, but specific mechanisms for zebra mussels affecting Diporeia abundance remain unidentified.

  16. Seasonal monitoring of blue mussel (Mytilus spp.) populations in a harbor area: A focus on responses to environmental factors and chronic contamination.

    PubMed

    Lacroix, C; Duvieilbourg, E; Guillou, N; Guyomarch, J; Bassoulet, C; Moraga, D; Chapalain, G; Auffret, M

    2017-08-01

    Coastal waters corresponding to macrotidal systems are among the most variable marine biotopes. Sessile animals as bivalve mollusks may however be found forming intertidal beds at high densities, as allowed by full adaptation to local conditions. A better knowledge of adaptive responses to environmental factors is required to foresee possible adverse effects of global change. At the sub-cellular level, transcriptional responses are among the earliest signals of environmental disturbances and they can reveal subtle and meaningful changes in organism exposed to stress. Three blue mussel (Mytilus spp.) populations inhabiting the Bay of Brest (France) in sites exposed to different levels of chronic pollution, from low to moderate, were surveyed upon a seasonal schedule, with special attention to the reproductive cycle. Major seawater parameters were monitored over a full-year in the framework of the S!RANO project, based on an automatic high frequency acquisition system installed aboard a ship of opportunity. The health status of mussels has been assessed by measuring a condition index and gametogenesis has been followed by histology. Selected biological responses to environmental stress were detected using a multimarker approach including expression of genes involved in chemical stress response and energetic metabolism, and cellular immune parameters. Environmental parameters showed deep seasonal variations which differed among sites. Most biological responses followed a seasonal pattern. Late winter and spring corresponded to an active reproduction period in the Bay of Brest. Earlier spawning was observed in harbor areas compared to the oceanic site and an altered physiological state was assumed in commercial harbor mussels during the reproductive period, suggesting that their health is compromised at this time of year. However, no signs of severe chemical stress were detected in both harbor mussel populations, which could reflect adaptive responses to adverse

  17. Restoration and colonization of freshwater mussels and fish in a southeastern United States tailwater

    USGS Publications Warehouse

    Layzer, J.B.; Scott, E.M.

    2006-01-01

    The French Broad River originates in North Carolina, flows west into Tennessee and at its confluence with the Holston River forms the Tennessee River. Douglas Dam, located on the French Broad River 52 km above its mouth, is operated primarily for peaking hydroelectric power and flood control. Prior to completion of the dam in 1943, the lower French Broad River contained about 53 species of freshwater mussels and 100 species of fish. By 1977, the fauna in the 52-km-long tailwater was reduced to 12 species of mussels and 42 native species of fish. Improvements in tailwater conditions occurred following initiation of minimum flows in 1987, and consistent reaeration of discharge in 1993. From 1988 to 2002, we sampled three sites (4, 28, and 39 km downstream of the dam) to monitor the fish assemblage. Each year since 1988, we have collected one or more additional species, indicating continued immigration. We collected 82 native and 9 exotic species of fish overall, but the maximum of 67 species in 1 year suggests that some species reside in the tailwater at low densities or all immigrants may not successfully colonize the tailwater. There is limited potential for most extirpated species of mussels to naturally recolonize the tailwater because source populations are isolated. Consequently, 19 754 adult mussels of 19 species were introduced between 1997 and 2000. Survival of translocated mussels has been high, and successful reproduction of at least one translocated species has occurred. Additionally, four mussel species are naturally colonizing the tailwater. Colonization and recruitment of additional mussel species is expected as populations of their host fishes increase. We believe that the improved conditions of the tailwater may allow for the re-establishment of sustaining populations of 30 mussel species of historic occurrence, but the continued operation of Douglas Dam as a peaking hydroelectric project will reduce the probability of successfully reintroducing some

  18. Dynamics of zebra finch and mockingbird vocalizations

    NASA Astrophysics Data System (ADS)

    Cimenser, Aylin

    Along with humans, whales, and bats, three groups of birds which include songbirds (oscines) such as the Zebra Finch (Taeniopygia guttata) and Mockingbird (Mimus polyglottos) are the only creatures known to learn sounds by imitation. Numerous similarities between human and songbird vocalizations exist and, recently, it has been shown that Zebra Finch in particular possesses a gene, FoxP2, known to be involved in human language. This thesis investigates song development in Zebra Finches, as well as the temporal dynamics of song in Mockingbirds. Zebra Finches have long been the system of choice for studying vocal development, ontogeny, and complexity in birdsong. Physicists find them intriguing because the spectrally complex vocalizations of the Zebra Finch can exhibit sudden transitions to chaotic dynamics, period doubling & mode-locking phenomena. Mockingbirds, by contrast, provide an ideal system to examine the richness of an avian repertoire, since these musically versatile songbirds typically know upwards of 200 songs. To analyse birdsong data, we have developed a novel clustering algorithm that can be applied to the bird's syllables, tracing their dynamics back to the earliest stages of vocal development. To characterize birdsong we have used Fourier techniques, based upon multitaper spectral analysis, to optimally work around the constraints imposed by (Heisenberg's) time-frequency uncertainty principle. Furthermore, estimates that provide optimal compromise between frequency and temporal resolution have beautiful connections with solutions to the Helmholtz wave equation in prolate spheroidal coordinates. We have used this connection to provide firm foundation for certain heuristics used in the literature to compute associated spectral derivatives and supply a pedagogical account here in this thesis. They are of interest because spectral derivatives emphasize sudden changes in the dynamics of the underlying phenomenon, and often provide a nice way to visualize

  19. FindZebra: a search engine for rare diseases.

    PubMed

    Dragusin, Radu; Petcu, Paula; Lioma, Christina; Larsen, Birger; Jørgensen, Henrik L; Cox, Ingemar J; Hansen, Lars Kai; Ingwersen, Peter; Winther, Ole

    2013-06-01

    The web has become a primary information resource about illnesses and treatments for both medical and non-medical users. Standard web search is by far the most common interface to this information. It is therefore of interest to find out how well web search engines work for diagnostic queries and what factors contribute to successes and failures. Among diseases, rare (or orphan) diseases represent an especially challenging and thus interesting class to diagnose as each is rare, diverse in symptoms and usually has scattered resources associated with it. We design an evaluation approach for web search engines for rare disease diagnosis which includes 56 real life diagnostic cases, performance measures, information resources and guidelines for customising Google Search to this task. In addition, we introduce FindZebra, a specialized (vertical) rare disease search engine. FindZebra is powered by open source search technology and uses curated freely available online medical information. FindZebra outperforms Google Search in both default set-up and customised to the resources used by FindZebra. We extend FindZebra with specialized functionalities exploiting medical ontological information and UMLS medical concepts to demonstrate different ways of displaying the retrieved results to medical experts. Our results indicate that a specialized search engine can improve the diagnostic quality without compromising the ease of use of the currently widely popular standard web search. The proposed evaluation approach can be valuable for future development and benchmarking. The FindZebra search engine is available at http://www.findzebra.com/. Copyright © 2013 Elsevier Ireland Ltd. All rights reserved.

  20. Widespread introgression in deep-sea hydrothermal vent mussels.

    PubMed

    Breusing, Corinna; Vrijenhoek, Robert C; Reusch, Thorsten B H

    2017-01-13

    The analysis of hybrid zones is crucial for gaining a mechanistic understanding of the process of speciation and the maintenance of species boundaries. Hybrid zones have been studied intensively in terrestrial and shallow-water ecosystems, but very little is known about their occurrence in deep-sea environments. Here we used diagnostic, single nucleotide polymorphisms in combination with one mitochondrial gene to re-examine prior hypotheses about a contact zone involving deep-sea hydrothermal vent mussels, Bathymodiolus azoricus and B. puteoserpentis, living along the Mid-Atlantic Ridge. Admixture was found to be asymmetric with respect to the parental species, while introgression was more widespread geographically than previously recognized. Admixed individuals with a majority of alleles from one of the parental species were most frequent in habitats corresponding to that species. Mussels found at a geographically intermediate vent field constituted a genetically mixed population that showed no evidence for hybrid incompatibilities, a finding that does not support a previously inferred tension zone model. Our analyses indicate that B. azoricus and B. puteoserpentis hybridize introgressively across a large geographic area without evidence for general hybrid incompatibilities. While these findings shed new light onto the genetic structure of this hybrid zone, many aspects about its nature still remain obscure. Our study sets a baseline for further research that should primarily focus on the acquisition of additional mussel samples and environmental data, a detailed exploration of vent areas and hidden populations as well as genomic analyses in both mussel hosts and their bacterial symbionts.

  1. A bibliography of "Dreissena polymorpha in European and Russian waters: 1964-1993"

    USGS Publications Warehouse

    Schloesser, Don W.; bij de Vaate, Abraham; Zimmerman, Ann

    1994-01-01

    A bibliography of over 1000 papers on the biology, impacts, and control of the zebra mussel (Dreissena polymorpha) in European and Russian waters is compiled to aid scientists and managers in addressing this species of economic and ecological importance. The bibliography primarily includes publications between the early 1960s and early 1990s but does contain some earlier references not found in another extensive bibliography published in 1964. This bibliography will be a valuable tool, especially to water users and environmental scientists in North America where zebra mussels have recently invaded and become established.

  2. Working towards developing potato tolerance of zebra chip disease: a food science perspective

    USDA-ARS?s Scientific Manuscript database

    Potato zebra chip is a major threat to worldwide potato production and is caused by ‘Candidatus Liberibacter solanacearum’ (Lso), which is vectored by potato psyllids. Albeit control can be achieved by use of insecticides to limit psyllid populations and therefore Lso spread, the recent development ...

  3. Intra-population variability of ocean acidification impacts on the physiology of Baltic blue mussels (Mytilus edulis): integrating tissue and organism response.

    PubMed

    Stapp, L S; Thomsen, J; Schade, H; Bock, C; Melzner, F; Pörtner, H O; Lannig, G

    2017-05-01

    Increased maintenance costs at cellular, and consequently organism level, are thought to be involved in shaping the sensitivity of marine calcifiers to ocean acidification (OA). Yet, knowledge of the capacity of marine calcifiers to undergo metabolic adaptation is sparse. In Kiel Fjord, blue mussels thrive despite periodically high seawater PCO 2 , making this population interesting for studying metabolic adaptation under OA. Consequently, we conducted a multi-generation experiment and compared physiological responses of F1 mussels from 'tolerant' and 'sensitive' families exposed to OA for 1 year. Family classifications were based on larval survival; tolerant families settled at all PCO 2 levels (700, 1120, 2400 µatm) while sensitive families did not settle at the highest PCO 2 (≥99.8% mortality). We found similar filtration rates between family types at the control and intermediate PCO 2 level. However, at 2400 µatm, filtration and metabolic scope of gill tissue decreased in tolerant families, indicating functional limitations at the tissue level. Routine metabolic rates (RMR) and summed tissue respiration (gill and outer mantle tissue) of tolerant families were increased at intermediate PCO 2 , indicating elevated cellular homeostatic costs in various tissues. By contrast, OA did not affect tissue and routine metabolism of sensitive families. However, tolerant mussels were characterised by lower RMR at control PCO 2 than sensitive families, which had variable RMR. This might provide the energetic scope to cover increased energetic demands under OA, highlighting the importance of analysing intra-population variability. The mechanisms shaping such difference in RMR and scope, and thus species' adaptation potential, remain to be identified.

  4. Toxicity of sediments from lead-zinc mining areas to juvenile freshwater mussels (Lampsilis siliquoidea) compared to standard test organisms

    USGS Publications Warehouse

    Besser, John M.; Ingersoll, Christopher G.; Brumbaugh, William G.; Kemble, Nile E.; May, Thomas W.; Wang, Ning; MacDonald, Donald D.; Roberts, Andrew D.

    2015-01-01

    Sediment toxicity tests compared chronic effects on survival, growth, and biomass of juvenile freshwater mussels (28-d exposures with Lampsilis siliquoidea) to the responses of standard test organisms—amphipods (28-d exposures with Hyalella azteca) and midges (10-d exposures with Chironomus dilutus)—in sediments from 2 lead–zinc mining areas: the Tri-State Mining District and Southeast Missouri Mining District. Mussel tests were conducted in sediments sieved to <0.25 mm to facilitate recovery of juvenile mussels (2–4 mo old). Sediments were contaminated primarily with lead, zinc, and cadmium, with greater zinc and cadmium concentrations in Tri-State sediments and greater lead concentrations in southeast Missouri sediments. The frequency of highly toxic responses (reduced 10% or more relative to reference sites) in Tri-State sediments was greatest for amphipod survival (25% of samples), midge biomass (20%), and mussel survival (14%). In southeast Missouri sediments, the frequency of highly toxic samples was greatest for mussel biomass (25%) and amphipod biomass (13%). Thresholds for metal toxicity to mussels, expressed as hazard quotients based on probable effect concentrations, were lower for southeast Missouri sediments than for Tri-State sediments. Southeast Missouri sites with toxic sediments had 2 or fewer live mussel taxa in a concurrent mussel population survey, compared with 7 to 26 taxa at reference sites. These results demonstrate that sediment toxicity tests with juvenile mussels can be conducted reliably by modifying existing standard methods; that the sensitivity of mussels to metals can be similar to or greater than standard test organisms; and that responses of mussels in laboratory toxicity tests are consistent with effects on wild mussel populations.

  5. High Pressure Inactivation of HAV within Mussels

    USDA-ARS?s Scientific Manuscript database

    The potential of hepatitis A virus (HAV) to be inactivated within Mediterranean mussels (Mytilus galloprovincialis) and blue mussels (Mytilus edulis) by high pressure processing was evaluated. HAV was bioaccumulated within mussels to approximately 6-log10 PFU by exposure of mussels to HAV-contamina...

  6. Physical and chemical constraints limit the habitat window for an endangered mussel

    USGS Publications Warehouse

    Campbell, Cara; Prestegaard, Karen L.

    2016-01-01

    Development of effective conservation and restoration strategies for freshwater pearly mussels requires identification of environmental constraints on the distributions of individual mussel species. We examined whether the spatial distribution of the endangered Alasmidonta heterodon in Flat Brook, a tributary of the upper Delaware River, was constrained by water chemistry (i.e., calcium availability), bed mobility, or both. Alasmidonta heterodon populations were bracketed between upstream reaches that were under-saturated with respect to aragonite and downstream reaches that were saturated for aragonite during summer baseflow but had steep channels with high bed mobility. Variability in bed mobility and water chemistry along the length of Flat Brook create a “habitat window” for A. heterodon defined by bed stability (mobility index ≤1) and aragonite saturation (saturation index ≥1). We suggest the species may exist in a narrow biogeochemical window that is seasonally near saturation. Alasmidonta heterodon populations may be susceptible to climate change or anthropogenic disturbances that increase discharge, decrease groundwater inflow or chemistry, and thus affect either bed mobility or aragonite saturation. Identifying the biogeochemical microhabitats and requirements of individual mussel species and incorporating this knowledge into management decisions should enhance the conservation and restoration of endangered mussel species.

  7. Freshwater mussels of Florida

    USGS Publications Warehouse

    Williams, James D.; Butler, Robert S.; Warren, Gary L.; Johnson, Nathan A.

    2014-01-01

    An exhaustive guide to all aspects of the freshwater mussel fauna in Florida,Freshwater Mussels of Florida covers the ecology, biology, distribution, and conservation of the many species of bivalve mollusks in the Sunshine State. In the past three decades, researchers, the public, businesses that depend on wildlife, and policy makers have given more attention to the threatened natural diversity of the Southeast, including freshwater mussels. This compendium meets the increasingly urgent need to catalog this imperiled group of aquatic organisms in the United States.

  8. Comparative analysis of riverscape genetic structure in rare, threatened and common freshwater mussels

    USGS Publications Warehouse

    Galbraith, Heather S.; Zanatta, David T.; Wilson, Chris C.

    2015-01-01

    Freshwater mussels (Bivalvia: Unionoida) are highly imperiled with many species on the verge of local extirpation or global extinction. This study investigates patterns of genetic structure and diversity in six species of freshwater mussels in the central Great Lakes region of Ontario, Canada. These species vary in their conservation status (endangered to not considered at risk), life history strategy, and dispersal capabilities. Evidence of historical genetic connectivity within rivers was ubiquitous across species and may reflect dispersal abilities of host fish. There was little to no signature of recent disturbance events or bottlenecks, even in endangered species, likely as a function of mussel longevity and historical population sizes (i.e., insufficient time for genetic drift to be detectable). Genetic structure was largely at the watershed scale suggesting that population augmentation via translocation within rivers may be a useful conservation tool if needed, while minimizing genetic risks to recipient sites. Recent interest in population augmentation via translocation and propagation may rely on these results to inform management of unionids in the Great Lakes region.

  9. Early detection monitoring for larval dreissenid mussels: How much plankton sampling is enough?

    USGS Publications Warehouse

    Counihan, Timothy D.; Bollens, Stephen M.

    2017-01-01

    The development of quagga and zebra mussel (dreissenids) monitoring programs in the Pacific Northwest provides a unique opportunity to evaluate a regional invasive species detection effort early in its development. Recent studies suggest that the ecological and economic costs of a dreissenid infestation in the Pacific Northwest of the USA would be significant. Consequently, efforts are underway to monitor for the presence of dreissenids. However, assessments of whether these efforts provide for early detection are lacking. We use information collected from 2012 to 2014 to characterize the development of larval dreissenid monitoring programs in the states of Idaho, Montana, Oregon, and Washington in the context of introduction and establishment risk. We also estimate the effort needed for high-probability detection of rare planktonic taxa in four Columbia and Snake River reservoirs and assess whether the current level of effort provides for early detection. We found that the effort expended to monitor for dreissenid mussels increased substantially from 2012 to 2014, that efforts were distributed across risk categories ranging from high to very low, and that substantial gaps in our knowledge of both introduction and establishment risk exist. The estimated volume of filtered water required to fully census planktonic taxa or to provide high-probability detection of rare taxa was high for the four reservoirs examined. We conclude that the current level of effort expended does not provide for high-probability detection of larval dreissenids or other planktonic taxa when they are rare in these reservoirs. We discuss options to improve early detection capabilities.

  10. The use of positive reinforcement in training zebra sharks (Stegostoma fasciatum).

    PubMed

    Marranzino, Ashley

    2013-01-01

    Positive reinforcement training (PRT) was used on 4 adult zebra sharks, Stegostoma fasciatum, housed at the Downtown Aquarium, Denver, to determine the ability of zebra sharks to become desensitized to various stimuli associated with veterinary procedures. One male and 3 female sharks were trained for 12 weeks. As a result of PRT, all 4 zebra sharks were desensitized to staying within a closed holding tank off of the main exhibit, the presence of multiple trainers in the closed holding tank, and tactile stimulation. One of the 4 zebra sharks was also successfully desensitized to the presence of a stretcher being brought into the holding tank. All of these procedures are common in veterinary examinations, and it is hoped that desensitization to these stimuli will reduce the stress associated with examinations. The training accomplished has allowed for easier maintenance of the zebra sharks by the aquarium staff and an improvement in the care of the sharks.

  11. High-density genetic map of Miscanthus sinensis reveals inheritance of zebra stripe

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Liu, Siyao; Clark, Lindsay V.; Swaminathan, Kankshita

    Miscanthus is a perennial C4 grass that has recently become an important bioenergy crop. The efficiency of breeding improved Miscanthus biomass cultivars could be greatly increased by marker-assisted selection. Thus, a high-density genetic map is critical to Miscanthus improvement. In this study, a mapping population of 261 F1 progeny was developed from a cross between two diploid M. sinensis cultivars, ‘Strictus’ and ‘Kaskade’. High-density genetic maps for the two parents were produced with 3044 newly developed single nucleotide polymorphisms (SNPs) obtained from restriction site-associated DNA sequencing, and 138 previously mapped GoldenGate SNPs. The female parent (‘Strictus’) map spanned 1599 cM,more » with 1989 SNPs on 19 linkage groups, and an average intermarker spacing of 0.8 cM. The length of the male parent (‘Kaskade’) map was 1612 cM, with 1821 SNPs, and an average intermarker spacing of 0.9 cM. The utility of the map was confirmed by locating quantitative trait loci (QTL) for the zebra-striped trait, which was segregating in this population. Three QTL for zebra-striped presence/absence (zb1, zb2 on LG 7, and zb3 on LG 10) and three for zebra-striped intensity (zbi1, zbi2, zbi3 on LGs 7, 10, 3) were identified. Each allele that caused striping was recessive. Incomplete penetrance was observed for each zb QTL, but penetrance was greatest when two or more zb QTL were homozygous for the causative alleles. Similarly, the intensity of striping was greatest when two or more zbi QTL were homozygous for alleles that conferred the trait. Comparative mapping indicated putative correspondence between zb3 and/or zbi2 on LG 10 to previously sequenced genes conferring zebra stripe in maize and rice. These results demonstrate that the new map is useful for identifying marker–trait associations. The mapped markers will become a valuable community resource, facilitating comparisons among studies and the breeding of Miscanthus.« less

  12. High-density genetic map of Miscanthus sinensis reveals inheritance of zebra stripe

    DOE PAGES

    Liu, Siyao; Clark, Lindsay V.; Swaminathan, Kankshita; ...

    2015-05-06

    Miscanthus is a perennial C4 grass that has recently become an important bioenergy crop. The efficiency of breeding improved Miscanthus biomass cultivars could be greatly increased by marker-assisted selection. Thus, a high-density genetic map is critical to Miscanthus improvement. In this study, a mapping population of 261 F1 progeny was developed from a cross between two diploid M. sinensis cultivars, ‘Strictus’ and ‘Kaskade’. High-density genetic maps for the two parents were produced with 3044 newly developed single nucleotide polymorphisms (SNPs) obtained from restriction site-associated DNA sequencing, and 138 previously mapped GoldenGate SNPs. The female parent (‘Strictus’) map spanned 1599 cM,more » with 1989 SNPs on 19 linkage groups, and an average intermarker spacing of 0.8 cM. The length of the male parent (‘Kaskade’) map was 1612 cM, with 1821 SNPs, and an average intermarker spacing of 0.9 cM. The utility of the map was confirmed by locating quantitative trait loci (QTL) for the zebra-striped trait, which was segregating in this population. Three QTL for zebra-striped presence/absence (zb1, zb2 on LG 7, and zb3 on LG 10) and three for zebra-striped intensity (zbi1, zbi2, zbi3 on LGs 7, 10, 3) were identified. Each allele that caused striping was recessive. Incomplete penetrance was observed for each zb QTL, but penetrance was greatest when two or more zb QTL were homozygous for the causative alleles. Similarly, the intensity of striping was greatest when two or more zbi QTL were homozygous for alleles that conferred the trait. Comparative mapping indicated putative correspondence between zb3 and/or zbi2 on LG 10 to previously sequenced genes conferring zebra stripe in maize and rice. These results demonstrate that the new map is useful for identifying marker–trait associations. The mapped markers will become a valuable community resource, facilitating comparisons among studies and the breeding of Miscanthus.« less

  13. DOE Office of Scientific and Technical Information (OSTI.GOV)

    Giamberini, Laure; Cajaraville, Miren P.

    In order to examine the possible use of lysosomal response as a biomarker of freshwater quality, structural changes of lysosomes were measured by image analysis in the digestive gland of the zebra mussel, Dreissena polymorpha, exposed in laboratory conditions to cadmium. Mussels were exposed to the metal (10 and 200 {mu}g/L) for 3 weeks and randomly collected after 7 and 21 days. At each treatment day, digestive tissues were excised and {beta}-glucuronidase activity was revealed in cryotome sections. Four stereological parameters were calculated: lysosomal volume density, lysosomal surface density, lysosomal surface to volume ratio, and lysosomal numerical density. The changesmore » observed in this study reflected a general activation of the lysosomal system, including an increase in both the number and the size of lysosomes in the digestive gland cells of mussels exposed to cadmium. The digestive lysosomal response in zebra mussels was related to exposure time and to metal concentration, demonstrating the potential of this biomarker in freshwater biomonitoring.« less

  14. Changes in the bottom fauna of western Lake Erie

    USGS Publications Warehouse

    Manny, Bruce A.; Schloesser, D.W.; Munawar, M.; Edsall, T.; Munawar, I.F.

    1999-01-01

    The bottom fauna of western Lake Erie has changed dramatically over the past 50 years in response to environmental degradation and biological invasions. In 1953, low dissolved oxygen reduced the biodiversity of that fauna, especially burrowing mayflies and freshwater mussels (Unionidae). Canada and the United States signed the Great Lakes Water Quality Agreement in 1972. By 1982, over 7 billion dollars were spent to improve wastewater treatment plants in the Great Lakes Basin. To assess how the bottom fauna responded to pollution abatement measures, we studied the distribution, abundance, and diversity of bottom fauna in western Lake Erie in 1982 and compared our findings to those of Carr and Hiltunen (1965). Zebra mussels (Dreissena polymorpha) invaded Lake Erie in 1986 and greatly altered these waters. For perspective, we also compared our results to bottom fauna present at the same stations in 1930 (by reference to data in Carr and Hiltunen, 1965) and reviewed the responses of burrowing mayflies and freshwater mussels to the zebra mussel invasion.

  15. Zebra stripes in the Atacama Desert: Fossil evidence of overland flow

    NASA Astrophysics Data System (ADS)

    Owen, Justine J.; Dietrich, William E.; Nishiizumi, Kuni; Chong, Guillermo; Amundson, Ronald

    2013-01-01

    Some hillslopes in the hyperarid region of the Atacama Desert in northern Chile have surface clasts organized into distinct, contour-parallel bands separated by bare soil. We call the bands "zebra stripes" due to the contrast between the darkly varnished clasts and the light-colored, salt-rich soil. Gravel that comprises the zebra stripes is sorted such that the coarsest clasts are at the downslope front and fine progressively upslope. How and when the zebra stripes formed are perplexing questions, particularly in a region experiencing prolonged hyperaridity. Using GoogleEarth, satellite imagery, and field observations, we report the first quantitative and qualitative observations of zebra stripes in order to test hypotheses of the mechanisms and timing of their formation. We consider soil shrink-swell, seismic shaking, and overland flow as possible formation mechanisms, and find that overland flow is the most likely. Based on cosmogenic 10Be concentrations in surface clasts, salt deposition rates from the atmosphere, and content in the soils, we propose that the salt-rich soils began accumulating ~ 106 y ago and the zebra stripes formed 103-104 y at the latest. The zebra stripe pattern has been preserved due to the self-stabilization of the clasts within the stripes and the continued absence of life (which would disturb the surface, as seen at a wetter site to the south). We conclude that the occurrence of zebra stripes is diagnostic of a set of distinct characteristics of local and/or regional precipitation, soil, hillslope form, and bedrock type.

  16. A zebra-band phenotype in maize can be suppressed in constant light, and results from mutation of a PPOXlike gene (protophorphyrinogen oxidase IX-like) for porphyrin biosynthesis

    USDA-ARS?s Scientific Manuscript database

    A zebra-band phenotype was identified in a maize population of transposon-tagged mutants (UniformMu, searchable by sequence at MaizeGDB.org). Genotype-phenotype analysis of an F2 family showed that the zebra stripes co-segregated with a single Mu insertion in the second exon of a Protoporphyrinogen ...

  17. Chronic environmental stress enhances tolerance to seasonal gradual warming in marine mussels

    PubMed Central

    Múgica, Maria; Izagirre, Urtzi; Sokolova, Inna M.

    2017-01-01

    In global climate change scenarios, seawater warming acts in concert with multiple stress sources, which may enhance the susceptibility of marine biota to thermal stress. Here, the responsiveness to seasonal gradual warming was investigated in temperate mussels from a chronically stressed population in comparison with a healthy one. Stressed and healthy mussels were subjected to gradual temperature elevation for 8 days (1°C per day; fall: 16–24°C, winter: 12–20°C, summer: 20–28°C) and kept at elevated temperature for 3 weeks. Healthy mussels experienced thermal stress and entered the time-limited survival period in the fall, became acclimated in winter and exhibited sublethal damage in summer. In stressed mussels, thermal stress and subsequent health deterioration were elicited in the fall but no transition into the critical period of time-limited survival was observed. Stressed mussels did not become acclimated to 20°C in winter, when they experienced low-to-moderate thermal stress, and did not experience sublethal damage at 28°C in summer, showing instead signs of metabolic rate depression. Overall, although the thermal threshold was lowered in chronically stressed mussels, they exhibited enhanced tolerance to seasonal gradual warming, especially in summer. These results challenge current assumptions on the susceptibility of marine biota to the interactive effects of seawater warming and pollution. PMID:28333994

  18. Mussel adhesion is dictated by time-regulated secretion and molecular conformation of mussel adhesive proteins

    NASA Astrophysics Data System (ADS)

    Petrone, Luigi; Kumar, Akshita; Sutanto, Clarinda N.; Patil, Navinkumar J.; Kannan, Srinivasaraghavan; Palaniappan, Alagappan; Amini, Shahrouz; Zappone, Bruno; Verma, Chandra; Miserez, Ali

    2015-10-01

    Interfacial water constitutes a formidable barrier to strong surface bonding, hampering the development of water-resistant synthetic adhesives. Notwithstanding this obstacle, the Asian green mussel Perna viridis attaches firmly to underwater surfaces via a proteinaceous secretion (byssus). Extending beyond the currently known design principles of mussel adhesion, here we elucidate the precise time-regulated secretion of P. viridis mussel adhesive proteins. The vanguard 3,4-dihydroxy-L-phenylalanine (Dopa)-rich protein Pvfp-5 acts as an adhesive primer, overcoming repulsive hydration forces by displacing surface-bound water and generating strong surface adhesion. Using homology modelling and molecular dynamics simulations, we find that all mussel adhesive proteins are largely unordered, with Pvfp-5 adopting a disordered structure and elongated conformation whereby all Dopa residues reside on the protein surface. Time-regulated secretion and structural disorder of mussel adhesive proteins appear essential for optimizing extended nonspecific surface interactions and byssus' assembly. Our findings reveal molecular-scale principles to help the development of wet-resistant adhesives.

  19. Song Recognition in Zebra Finches: Are There Sensitive Periods for Song Memorization?

    ERIC Educational Resources Information Center

    Braaten, Richard F.

    2010-01-01

    Male zebra finches learn to sing songs that they hear between 25 and 65 days of age, the sensitive period for song learning. In this experiment, male and female zebra finches were exposed to zebra finch songs either before (n = 9) or during (n = 4) the sensitive period. Following song exposure, recognition memory for the songs was assessed with an…

  20. Spatial variation in biofouling of a unionid mussel (Lampsilis siliquoidea) across the western basin of Lake Erie

    USGS Publications Warehouse

    Larson, James H.; Evans, Mary; Richardson, William B.; Schaeffer, Jeff; Nelson, John

    2016-01-01

    Invasion of North American waters by nonnative Dreissena polymorpha and D. rostriformis bugensishas resulted in declines of the Unionidae family of native North American mussels. Dreissenid mussels biofoul unionid mussels in large numbers and interfere with unionid movement, their acquisition of food, and the native mussels' ability to open and close their shells. Initial expectations for the Great Lakes included extirpation of unionids where they co-occurred with dreissenids, but recently adult and juvenile unionids have been found alive in several apparent refugia. These unionid populations may persist due to reduced dreissenid biofouling in these areas, and/or due to processes that remove biofoulers. For example locations inaccessible to dreissenid veligers may reduce biofouling and habitats with soft substrates may allow unionids to burrow and thus remove dreissenids. We deployed caged unionid mussels (Lampsilis siliquoidea) at 36 sites across the western basin of Lake Erie to assess spatial variation in biofouling and to identify other areas that might promote the persistence or recovery of native unionid mussels. Biofouling ranged from 0.03 – 26.33 g per mussel, reached a maximum in the immediate vicinity of the mouth of the Maumee River, and appeared to primarily consist of dreissenid mussels. A known mussel refugium in the vicinity of a power plant near the mouth of the Maumee actually exhibited very high biofouling rates, suggesting that low dreissenid colonization did not adequately explain unionid survival in this refugium. In contrast, the southern nearshore area of Lake Erie, near another refugium, had very low biofouling. A large stretch of the western basin appeared to have low biofouling rates and muddy substrates, raising the possibility that these open water areas could support remnant and returning populations of unionid mussels. Previous observations of unionid refugia and the occurrence of low biofouling rates in large areas of the western

  1. Evaluation of methods for assessing physiological biomarkers of stress in freshwater mussels

    USGS Publications Warehouse

    Fritts, Andrea K.; Peterson, James T.; Hazelton, Peter D.; Bringolf, Robert B.

    2015-01-01

    Freshwater mussel populations are highly susceptible to environmental alterations because of their diminished numbers and primarily sessile behaviors; nonlethal biomonitoring programs are needed to evaluate the health of populations prior to mass mortality events. Our objectives were to determine (i) which biochemical parameters in freshwater mussel hemolymph could be consistently quantified, (ii) how hemolymph parameters and tissue glycogen respond to a thermal stress gradient (25, 30, and 35 °C), and (iii) the effects of tissue and hemolymph extraction on long-term growth and survival of smaller- and larger-bodied mussel species. Glucose exhibited elevated expression in both species with increasing water temperature. Two transaminase enzymes had elevated expression in the 30 °C treatment. The effects of hemolymph extraction and tissue biopsies were evaluated with a large-bodied species, Elliptio crassidens, and a smaller species, Villosa vibex. Individuals were monitored for 820 to 945 days after one of four treatments: hemolymph extraction, tissue biopsy, tissue and hemolymph extraction, and control. Hemolymph extraction and tissue biopsy adversely affected survival of V. vibex, suggesting that these extraction methods may add some risk of reduced survival to smaller-bodied species. Survival of E. crassidens was not impaired by any of the treatments, supporting the use of these techniques in nonlethal biomonitoring programs for larger-bodied mussel species.

  2. Humoral response of captive zebra sharks Stegostoma fasciatum to salivary gland proteins of the leech Branchellion torpedinis.

    PubMed

    Marancik, David P; Leary, John H; Fast, Mark M; Flajnik, Martin F; Camus, Alvin C

    2012-10-01

    Parasitism by the marine leech Branchellion torpedinis is known to cause disease and mortality in captive elasmobranchs and is difficult to control when inadvertently introduced into public aquaria. Preliminary characterization of the salivary gland transcriptome of B. torpedinis has identified anticoagulants, proteases, and immunomodulators that may be secreted into host tissues to aid leech feeding. This retrospective study examined antigen-specific serum IgM responses in captive zebra sharks Stegostoma fasciatum to leech salivary gland extract. Antibody response was examined by ELISA and Western blot assays in 20 serum samples from six zebra sharks, with a 5 year history of leech infection, and 18 serum samples from 8 captive bred zebra sharks, with no history of leech exposure. ELISA demonstrated significantly higher serum IgM titers to salivary gland extract in exposed zebra sharks compared to the non-exposed population. No obvious trends in antibody titers were appreciated in exposed zebra sharks over a four-year period. One-dimensional and two-dimensional Western blot assays revealed IgM targeted specific salivary gland proteins within the 40, 55, 70 and 90 kD range. Antigenic proteins identified by liquid chromatography-tandem mass spectrometry and de novo peptide sequencing include a secreted disintegrin, metalloproteinase and thrombospondin motif containing protein (ADAMTS), tubulin, aldehyde dehydrogenase and two unknown proteins. Humoral immune responses to leech salivary gland proteins warrants further investigation as there may be options to exploit immune mechanisms to reduce parasite burdens in aquaria. Copyright © 2012 Elsevier Ltd. All rights reserved.

  3. Misidentification of freshwater mussel species (Bivalvia:Unionidae): contributing factors, management implications, and potential solutions

    USGS Publications Warehouse

    Shea, Colin P.; Peterson, James T.; Wisniewski, Jason M.; Johnson, Nathan A.

    2011-01-01

    Surveys of freshwater mussel populations are used frequently to inform conservation decisions by providing information about the status and distribution of species. It is generally accepted that not all mussels or species are collected during surveys, and incomplete detection of individuals and species can bias data and can affect inferences. However, considerably less attention has been given to the potential effects of species misidentification. To evaluate the prevalence of and potential reasons for species misidentification, we conducted a laboratory-based identification exercise and quantified the relationships between mussel species characteristics, observer experience, and misidentification rate. We estimated that misidentification was fairly common, with rates averaging 27% across all species and ranging from 0 to 56%, and was related to mussel shell characteristics and observer experience. Most notably, species with shell texturing were 6.09× less likely than smooth-shelled species to be misidentified. Misidentification rates declined with observer experience, but for many species the risk of misidentification averaged >10% even for observers with moderate levels of experience (5–6 y). In addition, misidentification rates among observers showed substantial variability after controlling for experience. Our results suggest that species misidentification may be common in field surveys of freshwater mussels and could potentially bias estimates of population status and trends. Misidentification rates possibly could be reduced through use of regional workshops, testing and certification programs, and the availability of archived specimens and tissue samples in museum collections.

  4. How the zebra got its stripes: a problem with too many solutions

    PubMed Central

    Larison, Brenda; Harrigan, Ryan J.; Thomassen, Henri A.; Rubenstein, Daniel I.; Chan-Golston, Alec M.; Li, Elizabeth; Smith, Thomas B.

    2015-01-01

    The adaptive significance of zebra stripes has thus far eluded understanding. Many explanations have been suggested, including social cohesion, thermoregulation, predation evasion and avoidance of biting flies. Identifying the associations between phenotypic and environmental factors is essential for testing these hypotheses and substantiating existing experimental evidence. Plains zebra striping pattern varies regionally, from heavy black and white striping over the entire body in some areas to reduced stripe coverage with thinner and lighter stripes in others. We examined how well 29 environmental variables predict the variation in stripe characteristics of plains zebra across their range in Africa. In contrast to recent findings, we found no evidence that striping may have evolved to escape predators or avoid biting flies. Instead, we found that temperature successfully predicts a substantial amount of the stripe pattern variation observed in plains zebra. As this association between striping and temperature may be indicative of multiple biological processes, we suggest that the selective agents driving zebra striping are probably multifarious and complex. PMID:26064590

  5. Spatial and temporal impacts of the Skjervøy harbour diesel spill on native population of blue mussels: A sub-Arctic case study.

    PubMed

    Breitwieser, Marine; Thomas-Guyon, Hélène; Huet, Valérie; Sagerup, Kjetil; Geraudie, Perrine

    2018-05-30

    This work was designed to investigate biological impacts on blue mussels (Mytilus edulis spp) after being exposed to diesel spill. On December 2013, an 180,000-litre accidental acute diesel spill was reported in a small harbour of northern Norway (Skjervøy). In order to assess the biological effects on the wild population of blue mussels, bivalves were collected at three different locations: at the oil-spill spot, at the other side of the harbour (opposite the oil-spill area), and in an uncontaminated site. Body burden and seawater samples were collected from a few days up to five months after the diesel spill. Biomarkers of oxidative stress and immunological effects were assessed in the blue mussels digestive glands. Our findings reported significant modulation of GST (detoxification), SOD (antioxidant response) and MDA (lipid peroxidation) in bivalves exposed to diesel with a similar response at two and five months after the spill. Laccase-type enzyme also highlighted an important aspect in terms of biomarker response of the immune function. Overall, our study demonstrated that some biomarkers returned to basal levels a few months after the diesel spill. Consequently, it highlighted the usefulness of normalised tools and guidelines for biomonitoring strategies after a diesel spill. Copyright © 2018 Elsevier Inc. All rights reserved.

  6. Mussel adhesion – essential footwork

    PubMed Central

    2017-01-01

    ABSTRACT Robust adhesion to wet, salt-encrusted, corroded and slimy surfaces has been an essential adaptation in the life histories of sessile marine organisms for hundreds of millions of years, but it remains a major impasse for technology. Mussel adhesion has served as one of many model systems providing a fundamental understanding of what is required for attachment to wet surfaces. Most polymer engineers have focused on the use of 3,4-dihydroxyphenyl-l-alanine (Dopa), a peculiar but abundant catecholic amino acid in mussel adhesive proteins. The premise of this Review is that although Dopa does have the potential for diverse cohesive and adhesive interactions, these will be difficult to achieve in synthetic homologs without a deeper knowledge of mussel biology; that is, how, at different length and time scales, mussels regulate the reactivity of their adhesive proteins. To deposit adhesive proteins onto target surfaces, the mussel foot creates an insulated reaction chamber with extreme reaction conditions such as low pH, low ionic strength and high reducing poise. These conditions enable adhesive proteins to undergo controlled fluid–fluid phase separation, surface adsorption and spreading, microstructure formation and, finally, solidification. PMID:28202646

  7. Sewage treatment plant associated genetic differentiation in the blue mussel from the Baltic Sea and Swedish west coast

    PubMed Central

    Lönn, Mikael; Lind, Emma E.; Świeżak, Justyna; Smolarz, Katarzyna; Grahn, Mats

    2016-01-01

    Human-derived environmental pollutants and nutrients that reach the aquatic environment through sewage effluents, agricultural and industrial processes are constantly contributing to environmental changes that serve as drivers for adaptive responses and evolutionary changes in many taxa. In this study, we examined how two types of point sources of aquatic environmental pollution, harbors and sewage treatment plants, affect gene diversity and genetic differentiation in the blue mussel in the Baltic Sea area and off the Swedish west coast (Skagerrak). Reference sites (REF) were geographically paired with sites from sewage treatments plant (STP) and harbors (HAR) with a nested sampling scheme, and genetic differentiation was evaluated using a high-resolution marker amplified fragment length polymorphism (AFLP). This study showed that genetic composition in the Baltic Sea blue mussel was associated with exposure to sewage treatment plant effluents. In addition, mussel populations from harbors were genetically divergent, in contrast to the sewage treatment plant populations, suggesting that there is an effect of pollution from harbors but that the direction is divergent and site specific, while the pollution effect from sewage treatment plants on the genetic composition of blue mussel populations acts in the same direction in the investigated sites. PMID:27812424

  8. Species Profiles: Life Histories and Environmental Requirements of Coastal Fishes and Invertebrates (Pacific Southwest) California Sea Mussel and Bay Mussel

    DTIC Science & Technology

    1988-09-01

    FishesS and Invertebrates (Pacific Southwest) CALIFORNIA SEA MUSSEL AND BAY MUSSEL Cn Coastal Ecology Group *Fish and Wildlife Service Waterways...September 1988 Species Profiles: Life Histories and Environmental Requirements of Coastal Fishes and Invertebrates (Pacific Southwest) CALIFORNIA SEA MUSSEL...AND BAY MUSSEL by William N. Shaw Fred Telonicher Marine Laboratory Humboldt State University Trinidad, CA 95570 Thomas J. Hassler U.S. Fish anu

  9. Intrinsic Variability in Shell and Soft Tissue Growth of the Freshwater Mussel Lampsilis siliquoidea

    PubMed Central

    Larson, James H.; Eckert, Nathan L.; Bartsch, Michelle R.

    2014-01-01

    Freshwater mussels are ecologically and economically important members of many aquatic ecosystems, but are globally among the most imperiled taxa. Propagation techniques for mussels have been developed and used to boost declining and restore extirpated populations. Here we use a cohort of propagated mussels to estimate the intrinsic variability in size and growth rate of Lampsilis siliquoidea (a commonly propagated species). Understanding the magnitude and pattern of variation in data is critical to determining whether effects observed in nature or experimental treatments are likely to be important. The coefficient of variation (CV) of L. siliquoidea soft tissues (6.0%) was less than the CV of linear shell dimensions (25.1–66.9%). Size-weight relationships were best when mussel width (the maximum left-right dimension with both valves appressed) was used as a predictor, but 95% credible intervals on these predictions for soft tissues were ∼145 mg wide (about 50% of the mean soft tissue mass). Mussels in this study were treated identically, raised from a single cohort and yet variation in soft tissue mass at a particular size class (as determined by shell dimensions) was still high. High variability in mussel size is often acknowledged, but seldom discussed in the context of mussel conservation. High variability will influence the survival of stocked juvenile cohorts, may affect the ability to experimentally detect sublethal stressors and may lead to incongruities between the effects that mussels have on structure (via hard shells) and biogeochemical cycles (via soft tissue metabolism). Given their imperiled status and longevity, there is often reluctance to destructively sample unionid mussel soft tissues even in metabolic studies (e.g., studies of nutrient cycling). High intrinsic variability suggests that using shell dimensions (particularly shell length) as a response variable in studies of sublethal stressors or metabolic processes will make confident

  10. Intrinsic variability in shell and soft tissue growth of the freshwater mussel Lampsilis siliquoidea

    USGS Publications Warehouse

    Larson, James H.; Eckert, Nathan L.; Bartsch, Michelle

    2014-01-01

    Freshwater mussels are ecologically and economically important members of many aquatic ecosystems, but are globally among the most imperiled taxa. Propagation techniques for mussels have been developed and used to boost declining and restore extirpated populations. Here we use a cohort of propagated mussels to estimate the intrinsic variability in size and growth rate of Lampsilis siliquoidea (a commonly propagated species). Understanding the magnitude and pattern of variation in data is critical to determining whether effects observed in nature or experimental treatments are likely to be important. The coefficient of variation (CV) of L. siliquoidea soft tissues (6.0%) was less than the CV of linear shell dimensions (25.1-66.9%). Size-weight relationships were best when mussel width (the maximum left-right dimension with both valves appressed) was used as a predictor, but 95% credible intervals on these predictions for soft tissues were ~145 mg wide (about 50% of the mean soft tissue mass). Mussels in this study were treated identically, raised from a single cohort and yet variation in soft tissue mass at a particular size class (as determined by shell dimensions) was still high. High variability in mussel size is often acknowledged, but seldom discussed in the context of mussel conservation. High variability will influence the survival of stocked juvenile cohorts, may affect the ability to experimentally detect sublethal stressors and may lead to incongruities between the effects that mussels have on structure (via hard shells) and biogeochemical cycles (via soft tissue metabolism). Given their imperiled status and longevity, there is often reluctance to destructively sample unionid mussel soft tissues even in metabolic studies (e.g., studies of nutrient cycling). High intrinsic variability suggests that using shell dimensions (particularly shell length) as a response variable in studies of sublethal stressors or metabolic processes will make confident

  11. Effects of flow restoration on mussel growth in a Wild and Scenic North American River

    PubMed Central

    2013-01-01

    Background Freshwater mussels remain among the most imperiled species in North America due primarily to habitat loss or degradation. Understanding how mussels respond to habitat changes can improve conservation efforts. Mussels deposit rings in their shell in which age and growth information can be read, and thus used to evaluate how mussels respond to changes in habitat. However, discrepancies between methodological approaches to obtain life history information from growth rings has led to considerable uncertainty regarding the life history characteristics of many mussel species. In this study we compared two processing methods, internal and external ring examination, to obtain age and growth information of two populations of mussels in the St. Croix River, MN, and evaluated how mussel growth responded to changes in the operation of a hydroelectric dam. Results External ring counts consistently underestimated internal ring counts by 4 years. Despite this difference, internal and external growth patterns were consistent. In 2000, the hydroelectric dam switched from operating on a peaking schedule to run-of-the-river/partial peaking. Growth patterns between an upstream and downstream site of the dam were similar both before and after the change in operation. At the downstream site, however, older mussels had higher growth rates after the change in operation than the same sized mussels collected before the change. Conclusions Because growth patterns between internal and external processing methods were consistent, we suggest that external processing is an effective method to obtain growth information despite providing inaccurate age information. External processing is advantageous over internal processing due to its non-destructive nature. Applying this information to analyze the influence of the operation change in the hydroelectric dam, we suggest that changing to run-of-the-river/partial peaking operation has benefited the growth of older mussels below the dam

  12. How landscape scale changes affect ecological processes in conservation areas: external factors influence land use by zebra (Equus burchelli) in the Okavango Delta.

    PubMed

    Bartlam-Brooks, Hattie L A; Bonyongo, Mpaphi C; Harris, Stephen

    2013-09-01

    Most large-bodied wildlife populations in sub-Saharan Africa only survive in conservation areas, but are continuing to decline because external changes influence ecological processes within reserves, leading to a lack of functionality. However, failure to understand how landscape scale changes influence ecological processes limits our ability to manage protected areas. We used GPS movement data to calculate dry season home ranges for 14 zebra mares in the Okavango Delta and investigated the effects of a range of landscape characteristics (number of habitat patches, mean patch shape, mean index of juxtaposition, and interspersion) on home range size. Resource utilization functions (RUF) were calculated to investigate how specific landscape characteristics affected space use. Space use by all zebra was clustered. In the wetter (Central) parts of the Delta home range size was negatively correlated with the density of habitat patches, more complex patch shapes, low juxtaposition of habitats and an increased availability of floodplain and grassland habitats. In the drier (Peripheral) parts of the Delta, higher use by zebra was also associated with a greater availability of floodplain and grassland habitats, but a lower density of patches and simpler patch shapes. The most important landscape characteristic was not consistent between zebra within the same area of the Delta, suggesting that no single foraging strategy is substantially superior to others, and so animals using different foraging strategies may all thrive. The distribution and complexity of habitat patches are crucial in determining space use by zebra. The extent and duration of seasonal flooding is the principal process affecting habitat patch characteristics in the Okavango Delta, particularly the availability of floodplains, which are the habitat at greatest risk from climate change and anthropogenic disturbance to the Okavango's catchment basin. Understanding how the factors that determine habitat

  13. Hydraulic modeling of mussel habitat at a bridge-replacement site, Allegheny River, Pennsylvania, USA

    USGS Publications Warehouse

    Fulton, John W.; Wagner, Chad R.; Rogers, Megan E.; Zimmerman, Gregory F.

    2010-01-01

    Based on the statistical targets established, the hydraulic model results suggest that an additional 2428 m2 or a 30-percent increase in suitable mussel habitat could be generated at the replacement-bridge site when compared to the baseline condition associated with the existing bridge at that same location. The study did not address the influences of substrate, acid mine drainage, sediment loads from tributaries, and surface-water/ground-water exchange on mussel habitat. Future studies could include methods for quantifying (1) channel–substrate composition and distribution using tools such as hydroacoustic echosounders specifically designed and calibrated to identify bed composition and mussel populations, (2) surface-water and ground-water interactions, and (3) a high-streamflow event.

  14. Cyanobacteria reduce quagga mussel (Dreissena rostriformis bugensis) spawning and fertilization success

    USGS Publications Warehouse

    Boegehold, Anna G.; Johnson, Nicholas; Ran, Jeffrey L.; Kashian, Donna R.

    2018-01-01

    Quagga mussels (Dreissena rostriformis bugensis) are highly fecund broadcast spawners invasive to freshwaters of North America and western Europe. We hypothesized that environmental cues from phytoplankton can trigger gamete release in quagga mussels. Nutritious algae may stimulate dreissenid spawning, but less palatable food, such as bloom-forming cyanobacteria, could be a hindrance. The objective of our study was to test whether exposure to cyanobacteria can inhibit quagga mussel spawning and fertilization. We assessed spawning in the presence of serotonin, a known spawning inducer, where adult quagga mussels placed in individual vials were exposed to 13 cyanobacteria cultures and purified algal toxin (microcystin-LR) with artificial lake water as the control. Fertilization success was evaluated by combining eggs with sperm in conjunction with cyanobacteria, and enumerating zygote formation marked by cellular cleavage. Several cyanobacterial strains reduced spawning and fertilization success, but microcystin-LR had no effect. Fertilization was more sensitive to cyanobacteria than gamete release. Only 1 culture, Aphanizomenon flos-aquae, inhibited spawning, whereas 6 cultures consisting of Anabaena flos-aquae, Dolichospermum lemmermanii, Gloeotrichia echinulata, Lyngbya wollei, and 2 Microcystis aeruginosa isolates reduced fertilization rates by up to 44%. The effects of cyanobacteria on reproduction in invasive freshwater mussels in the wild have not yet been identified. However, our laboratory studies show that concentrations of cyanobacteria that are possible during bloom conditions probably limit reproduction. Reproductive consequences on wild populations may become more prevalent as cyanobacteria blooms occur earlier in the year, making overlap between blooms and mussel spawning more common. Describing the mechanism by which cyanobacteria inhibit spawning and fertilization could reveal novel control methods to limit reproduction of this invasive

  15. MC1R Genotype and Plumage Colouration in the Zebra Finch (Taeniopygia guttata): Population Structure Generates Artefactual Associations

    PubMed Central

    Hoffman, Joseph I.; Krause, E. Tobias; Lehmann, Katrin; Krüger, Oliver

    2014-01-01

    Polymorphisms at the melanocortin-1 receptor (MC1R) gene have been linked to coloration in many vertebrate species. However, the potentially confounding influence of population structure has rarely been controlled for. We explored the role of the MC1R in a model avian system by sequencing the coding region in 162 zebra finches comprising 79 wild type and 83 white individuals from five stocks. Allelic counts differed significantly between the two plumage morphs at multiple segregating sites, but these were mostly synonymous. To provide a control, the birds were genotyped at eight microsatellites and subjected to Bayesian cluster analysis, revealing two distinct groups. We therefore crossed wild type with white individuals and backcrossed the F1s with white birds. No significant associations were detected in the resulting offspring, suggesting that our original findings were a byproduct of genome-wide divergence. Our results are consistent with a previous study that found no association between MC1R polymorphism and plumage coloration in leaf warblers. They also contribute towards a growing body of evidence suggesting that care should be taken to quantify, and where necessary control for, population structure in association studies. PMID:24489736

  16. Egg fertilisation in a freshwater mussel: effects of distance, flow and male density

    Treesearch

    Tyler L. Mosley; Wendell R. Haag; James A. Stoeckel

    2014-01-01

    1. Small or sparse populations can experience Allee effects if egg fertilisation is reduced because of a shortage of sperm. 2. Freshwater mussels are spermcasters that often occur as sparse, patchy populations. Previous studies suggested that sperm shortage limits these populations unless facultative hermaphroditism and selffertilisation occur at low density...

  17. Changes in the Lake Michigan food web following dreissenid mussel invasions: A synthesis

    USGS Publications Warehouse

    Madenjian, Charles P.; Bunnell, David B.; Warner, David M.; Pothoven, Steven A.; Fahnenstiel, Gary L.; Nalepa, Thomas F.; Vanderploeg, Henry A.; Tsehaye, Iyob; Claramunt, Randall M.; Clark, Richard D

    2015-01-01

    Using various available time series for Lake Michigan, we examined changes in the Lake Michigan food web following the dreissenid mussel invasions and identified those changes most likely attributable to these invasions, thereby providing a synthesis. Expansion of the quagga mussel (Dreissena rostriformis bugensis) population into deeper waters, which began around 2004, appeared to have a substantial predatory effect on both phytoplankton abundance and primary production, with annual primary production in offshore (> 50 m deep) waters being reduced by about 35% by 2007. Primary production likely decreased in nearshore waters as well, primarily due to predatory effects exerted by the quagga mussel expansion. The drastic decline inDiporeia abundance in Lake Michigan during the 1990s and 2000s has been attributed to dreissenid mussel effects, but the exact mechanism by which the mussels were negatively affecting Diporeia abundance remains unknown. In turn, decreased Diporeiaabundance was associated with reduced condition, growth, and/or energy density in alewife (Alosa pseudoharengus), lake whitefish (Coregonus clupeaformis), deepwater sculpin (Myoxocephalus thompsonii), and bloater (Coregonus hoyi). However, lake-wide biomass of salmonines, top predators in the food web, remained high during the 2000s, and consumption of alewives by salmonines actually increased between the 1980–1995 and 1996–2011 time periods. Moreover, abundance of the lake whitefish population, which supports Lake Michigan's most valuable commercial fishery, remained at historically high levels during the 2000s. Apparently, counterbalancing mechanisms operating within the complex Lake Michigan food web have enabled salmonines and lake whitefish to retain relatively high abundances despite reduced primary production.

  18. Toxicity decrease in urban wastewaters treated by a new biofiltration process.

    PubMed

    Binelli, A; Magni, S; Della Torre, C; Parolini, M

    2015-12-15

    We carried out a project aimed to evaluate the possible role played by the freshwater zebra mussel (Dreissena polymorpha) in the possible decrease of some environmental pollutants recalcitrant to tradition wastewater treatments. By the help of a pilot-plant built in the largest wastewater treatment plant of Milan (Italy), we tested several waste mixtures in order to measure the chemicals' abatement made by mussels' biofiltration. This study represents the last step of the wider project and it aimed to evaluate if the decrease in the concentration of some urban pollutants measured in wastewaters was followed by a corresponding toxicity reduction. Thus, we performed 7-day exposures under laboratory conditions to test the toxicity of the raw wastewaters and those preliminary filtered by zebra mussels, through the measurement of different end-points of acute and chronic toxicity. Results showed a clear positive effect of mussels' biofiltration mainly to decrease the acute toxicity made by the two tested wastewater mixtures, while the biomarkers' suite used to evaluate the chronic toxicity showed contradictory results. Copyright © 2015 Elsevier B.V. All rights reserved.

  19. Flow cytometric monitoring of bacterioplankton phenotypic diversity predicts high population-specific feeding rates by invasive dreissenid mussels.

    PubMed

    Props, Ruben; Schmidt, Marian L; Heyse, Jasmine; Vanderploeg, Henry A; Boon, Nico; Denef, Vincent J

    2018-02-01

    Species invasion is an important disturbance to ecosystems worldwide, yet knowledge about the impacts of invasive species on bacterial communities remains sparse. Using a novel approach, we simultaneously detected phenotypic and derived taxonomic change in a natural bacterioplankton community when subjected to feeding pressure by quagga mussels, a widespread aquatic invasive species. We detected a significant decrease in diversity within 1 h of feeding and a total diversity loss of 11.6 ± 4.1% after 3 h. This loss of microbial diversity was caused by the selective removal of high nucleic acid populations (29 ± 5% after 3 h). We were able to track the community diversity at high temporal resolution by calculating phenotypic diversity estimates from flow cytometry (FCM) data of minute amounts of sample. Through parallel FCM and 16S rRNA gene amplicon sequencing analysis of environments spanning a broad diversity range, we showed that the two approaches resulted in highly correlated diversity measures and captured the same seasonal and lake-specific patterns in community composition. Based on our results, we predict that selective feeding by invasive dreissenid mussels directly impacts the microbial component of the carbon cycle, as it may drive bacterioplankton communities toward less diverse and potentially less productive states. © 2017 Society for Applied Microbiology and John Wiley & Sons Ltd.

  20. Thiaminase activity in native freshwater mussels

    USGS Publications Warehouse

    Blakeslee, Carrie J.; Sweet, Stephanie; Galbraith, Heather S.; Honeyfield, Dale C.

    2015-01-01

    Thiamine (vitamin B1) deficiency in the Great Lakes has been attributed to elevated levels of thiaminase I enzyme activity in invasive prey species; however, few studies have investigated thiaminase activity in native prey species. Some of the highest levels of thiaminase activity have been measured in invasive dreissenid mussels with little understanding of background levels contributed by native freshwater mussels (Bivalvia: Unionidae). In this study, thiaminase activity was measured in two freshwater mussel species, Elliptio complanata and Strophitus undulatus, from the Delaware and Susquehanna River drainage basins located in north eastern United States. Thiaminase activity was also measured in gravid and non-gravid S. undulatus. Average thiaminase activity differed significantly between species (7.2 and 42.4 μmol/g/min, for E. complanata and S. undulatus respectively) with no differences observed between drainage basins. Gravid S. undulatus had significantly lower thiaminase activity (28.0 μmol/g/min) than non-gravid mussels (42.4 μmol/g/min). Our results suggest that a suite of factors may regulate thiaminase activity in freshwater mussels and that native freshwater mussel thiaminase activity is within the range observed for invasive dreissenids. These results add to our understanding of the complexities in identifying the ecological conditions that set the stage for thiamine deficiency.

  1. Effectiveness of lemon juice in the elimination of Salmonella Typhimurium in stuffed mussels.

    PubMed

    Kişla, Duygu

    2007-12-01

    Street foods are becoming more and more prominent in countries all over the world. There are many reports of disease due to consumption of street foods contaminated by pathogens. With the modern trend toward more natural preservatives, the use of organic acids can achieve a good microbiological safety in food. In the present study, stuffed mussels were inoculated with Salmonella Typhimurium suspension to provide initial populations of approximately 6 and 3 log CFU/g. After inoculation, samples were treated with fresh lemon juice and lemon dressing for 0, 5, and 15 min, and pathogens were enumerated by using direct plating on brilliant green agar. Treatment of stuffed mussels inoculated at high inoculum level, with lemon juice and lemon dressing for different exposure times caused reduction ranging between 0.25 and 0.56 log CFU/g and 0.5 and 0.69 log CFU/g, respectively, whereas in stuffed-mussel samples inoculated at low level, lemon juice and lemon dressing caused 0.08 to 0.25 log CFU/g and 0.22 to 0.78 log CFU/g reductions, respectively. Results of the study showed that both lemon juice and lemon dressing used as flavoring and acidifying agents for stuffed mussels caused slight decrease in Salmonella Typhimurium as an immediate inhibitor, but this effect increased by time. However, treatment of stuffed mussels with the inhibitors until 15 min is not enough to prevent Salmonella Typhimurium outbreaks related to stuffed mussels.

  2. Freshwater mussel response to bedform movement: experimental stream studies

    NASA Astrophysics Data System (ADS)

    Kozarek, J. L.; MacGregor, K. R.; Hornbach, D.; Hove, M.

    2017-12-01

    Freshwater mussels are intrinsically linked to near-bed sediment dynamics, but it remains unclear how mussels respond to changing sediment loads across spatial and temporal scales. The interactions between mussels and sediment transport are complex and often involve feedback loops. Mussels are filter feeders removing suspended particles from the water column and the physical presence of mussels can have significant impacts on the structure of riverbed habitat. We investigated the feedbacks between mussels, flow, and migrating bedforms during flood experiments in the St. Anthony Falls Laboratory Outdoor StreamLab (OSL) at the University of Minnesota. The OSL is a field-scale sand-bed meandering stream channel with independent control over sediment feed (recirculated) and water flow (diverted from the Mississippi River). Mussel location, orientation to flow, and protrusion from sediment was surveyed immediately before, after, and one and two days after each flood event. Flow fields, bed shear stress, bedform migration, and bar topography were measured during each flooding event with and without mussels present (density = 4/m2 and 8/m2) to quantify the influence of mussels on channel morphology and bedform migration. Mobile bedforms (up to 14 cm high) were present for all flood events with quasi-equilibrium, aggrading, and degrading bed conditions. Mussels moved little horizontally during all flood events, but were shown to move quickly to deeper water after the flood receded. However, mussels moved vertically, burrowing or being buried under mobile bedforms, during each flood event. The research presented here will focus on feedbacks between three mussel species with different shell sculptures, flow conditions, and migrating bedforms during flooding events. These results reveal how freshwater mussels respond to and affect flow and sediment transport during flood events that are difficult to observe in the field.

  3. Assessment of the fitness of the mussel Mytilus galloprovincialis two years after the Hebei Spirit oil spill.

    PubMed

    Donaghy, Ludovic; Hong, Hyun-Ki; Kim, Moonkoo; Park, Heung-Sik; Choi, Kwang-Sik

    2016-12-15

    In December 2007, >150km of the West coast of Korea were heavily polluted by crude oil leaked from the oil tanker Hebei Spirit, leading to mass mortality of bivalve mollusks on the intertidal areas. Two years after, mussels Mytilus galloprovincialis were collected from two impacted sites to investigate sub-lethal effects of the oil spill. Tissue content in polycyclic aromatic hydrocarbons (PAHs), hemocyte parameters, reproductive status and energetic reserves were analyzed. PAHs in tissues of mussels as well as hemocyte parameters were not different between impacted and control sites. Energetic reserves were altered in mussels from the impacted sites. Glycogen content remained low at polluted sites, whatever the season. Two years after the Hebei Spirit oil spill, mussels then presented altered energetic metabolism. Further investigations are thus warranted to monitor the sustainability of mussel populations on the oil spilled West coast of Korea. Copyright © 2016 Elsevier Ltd. All rights reserved.

  4. Drought-induced changes in flow regimes lead to long-term losses in mussel-provided ecosystem services

    PubMed Central

    Vaughn, Caryn C; Atkinson, Carla L; Julian, Jason P

    2015-01-01

    Extreme hydro-meteorological events such as droughts are becoming more frequent, intense, and persistent. This is particularly true in the south central USA, where rapidly growing urban areas are running out of water and human-engineered water storage and management are leading to broad-scale changes in flow regimes. The Kiamichi River in southeastern Oklahoma, USA, has high fish and freshwater mussel biodiversity. However, water from this rural river is desired by multiple urban areas and other entities. Freshwater mussels are large, long-lived filter feeders that provide important ecosystem services. We ask how observed changes in mussel biomass and community composition resulting from drought-induced changes in flow regimes might lead to changes in river ecosystem services. We sampled mussel communities in this river over a 20-year period that included two severe droughts. We then used laboratory-derived physiological rates and river-wide estimates of species-specific mussel biomass to estimate three aggregate ecosystem services provided by mussels over this time period: biofiltration, nutrient recycling (nitrogen and phosphorus), and nutrient storage (nitrogen, phosphorus, and carbon). Mussel populations declined over 60%, and declines were directly linked to drought-induced changes in flow regimes. All ecosystem services declined over time and mirrored biomass losses. Mussel declines were exacerbated by human water management, which has increased the magnitude and frequency of hydrologic drought in downstream reaches of the river. Freshwater mussels are globally imperiled and declining around the world. Summed across multiple streams and rivers, mussel losses similar to those we document here could have considerable consequences for downstream water quality although lost biofiltration and nutrient retention. While we cannot control the frequency and severity of climatological droughts, water releases from reservoirs could be used to augment stream flows and

  5. Spatial patterns of native freshwater mussels in the Upper Mississippi River

    USGS Publications Warehouse

    Ries, Patricia R.; DeJager, Nathan R.; Zigler, Steven J.; Newton, Teresa

    2016-01-01

    Multiple physical and biological factors structure freshwater mussel communities in large rivers, and their distributions have been described as clumped or patchy. However, few surveys of mussel populations have been conducted over areas large enough and at resolutions fine enough to quantify spatial patterns in their distribution. We used global and local indicators of spatial autocorrelation (i.e., Moran’s I) to quantify spatial patterns of adult and juvenile (≤5 y of age) freshwater mussels across multiple scales based on survey data from 4 reaches (navigation pools 3, 5, 6, and 18) of the Upper Mississippi River, USA. Native mussel densities were sampled at a resolution of ∼300 m and across distances ranging from 21 to 37 km, making these some of the most spatially extensive surveys conducted in a large river. Patch density and the degree and scale of patchiness varied by river reach, age group, and the scale of analysis. In all 4 pools, some patches of adults overlapped patches of juveniles, suggesting spatial and temporal persistence of adequate habitat. In pools 3 and 5, patches of juveniles were found where there were few adults, suggesting recent emergence of positive structuring mechanisms. Last, in pools 3, 5, and 6, some patches of adults were found where there were few juveniles, suggesting that negative structuring mechanisms may have replaced positive ones, leading to a lack of localized recruitment. Our results suggest that: 1) the detection of patches of freshwater mussels requires a multiscaled approach, 2) insights into the spatial and temporal dynamics of structuring mechanisms can be gained by conducting independent analyses of adults and juveniles, and 3) maps of patch distributions can be used to guide restoration and management actions and identify areas where mussels are most likely to influence ecosystem function.

  6. Cyanobacteria reduce quagga mussel (Dreissena rostriformis bugensis) spawning and fertilization success

    USGS Publications Warehouse

    Boegehold, Anna G; Johnson, Nicholas; Ran, Jeffrey L; Kashian, Donna R

    2018-01-01

    exposure to cyanobacteria can inhibit quagga mussel spawning and fertilization. We assessed spawning in the presence of serotonin, a known spawning inducer, where adult quagga mussels placed in individual vials were exposed to 13 cyanobacteria cultures and purified algal toxin (microcystin-LR) with artificial lake water as the control. Fertilization success was evaluated by combining eggs with sperm in conjunction with cyanobacteria, and enumerating zygote formation marked by cellular cleavage. Several cyanobacterial strains reduced spawning and fertilization success, but microcystin-LR had no effect. Fertilization was more sensitive to cyanobacteria than gamete release. Only 1 culture, Aphanizomenon flos-aquae, inhibited spawning, whereas 6 cultures consisting of Anabaena flos-aquae, Dolichospermum lemmermanii, Gloeotrichia echinulata, Lyngbya wollei, and 2 Microcystis aeruginosa isolates reduced fertilization rates by up to 44%. The effects of cyanobacteria on reproduction in invasive freshwater mussels in the wild have not yet been identified. However, our laboratory studies show that concentrations of cyanobacteria that are possible during bloom conditions probably limit reproduction. Reproductive consequences on wild populations may become more prevalent as cyanobacteria blooms occur earlier in the year, making overlap between blooms and mussel spawning more common. Describing the mechanism by which cyanobacteria inhibit spawning and fertilization could reveal novel control methods to limit reproduction of this invasive species.

  7. A holistic approach to taxonomic evaluation of two closely related endangered freshwater mussel species, the oyster mussel Epioblasma capsaeformis and tan riffleshell Epioblasma florentina walkeri (Bivalvia: Unionidae)

    USGS Publications Warehouse

    Jones, J.W.; Neves, R.J.; Ahlstedt, S.A.; Hallerman, E.M.

    2006-01-01

    Species in the genus Epioblasma have specialized life history requirements and represent the most endangered genus of freshwater mussels (Unionidae) in the world. A genetic characterization of extant populations of the oyster mussel E. capsaeformis and tan riffleshell E. florentina walkeri sensu late was conducted to assess taxonomic validity and to resolve conservation issues for recovery planning. These mussel species exhibit pronounced phenotypic variation, but were difficult to characterize phylogenetically using DNA sequences. Monophyletic lineages, congruent with phenotypic variation among species, were obtained only after extensive analysis of combined mitochondrial (1396 bp of 16S, cytochrome-b, and ND1) and nuclear (515 bp of ITS-1) DNA sequences. In contrast, analysis of variation at 10 hypervariable DNA microsatellite loci showed moderately to highly diverged populations based on FST and R ST values, which ranged from 0.12 to 0.39 and 0.15 to 0.71, respectively. Quantitative variation between species was observed in fish-host specificity, with transformation success of glochidia of E. capsaeformis significantly greater (P<0.05) on greenside darter Etheostoma blennioides, and that of E. f. walkeri significantly greater (P<0.05) on fantail darter Etheostoma flabellare. Lengths of glochidia differed significantly (P<0.001) among species and populations, with mean sizes ranging from 241 to 272 ??m. The texture and colour of the mantle-pad of E. capsaeformis sensu stricto is smooth and bluish-white, whereas that of E. f. walkeri is pustuled and brown, with tan mottling. Based on extensive molecular, morphological and life history data, the population of E. capsaeformis from the Duck River, Tennessee, USA is proposed as a separate species, and the population of E. f. walkeri from Indian Creek, upper Clinch River, Virginia, USA is proposed as a distinct subspecies.

  8. A Survey of the Freshwater Mussel Fauna of the Little Kanawha River Basin,

    DTIC Science & Technology

    Mussels, * Aquatic biology, Surveys, Rivers, Basins(Geographic), Natural resources, Population, Distribution, Sampling, Environmental impact...Chemical analysis, Pesticides, Metals, Water quality, Waste water , Waste management, Decision making, West Virginia, Fresh water , Workshops

  9. Establishment of the green mussel, Perna viridis (Linnaeus 1758) (Mollusca: Mytilidae) on the West Coast of Florida

    USGS Publications Warehouse

    Benson, A.J.; Marelli, D.C.; Frischer, M.E.; Danforth, J.M.; Williams, J.D.

    2001-01-01

    In 1999, the green mussel, Perna viridis, was first observed in Tampa Bay, Florida. This was the first reported occurrence of this Indo-Pacific marine bivalve in North America. The mussels found in Tampa Bay were confirmed to be P. viridis based on both morphological and genetic characteristics. Since the initial discovery, surveys in Tampa Bay and on the west coast of Florida have documented the growth, recruitment, and range expansion of P. viridis. From November 1999 to July 2000, the mean shell length of a Tampa Bay population increased from 49.0 mm to 94.1 mm, an increase of 97%. Populations of P. viridis are successfully reproducing in Tampa Bay. Recruitment was observed on sampling plates in May and continued through July 2000. The full extent of mussel colonization is not clear, but mussels were found outside Tampa Bay in St. Petersburg, Florida, south to Venice. Based on these studies it is evident that P. viridis has successfully invaded Tampa Bay and the west coast of Florida. The long-term impact of P. viridis on native communities off the west coast of Florida cannot be predicted at this time.

  10. Growth potential of blue mussels (M. edulis) exposed to different salinities evaluated by a Dynamic Energy Budget model

    NASA Astrophysics Data System (ADS)

    Maar, Marie; Saurel, Camille; Landes, Anja; Dolmer, Per; Petersen, Jens Kjerulf

    2015-08-01

    For blue mussels, Mytilus edulis, one major constrain in the Baltic Sea is the low salinities that reduce the efficiency of mussel production. However, the effects of living in low and variable salinity regimes are rarely considered in models describing mussel growth. The aim of the present study was to incorporate the effects of low salinity into an eco-physiological model of blue mussels and to identify areas suitable for mussel production. A Dynamic Energy Budget (DEB) model was modified with respect to i) the morphological parameters (DW/WW-ratio, shape factor), ii) change in ingestion rate and iii) metabolic costs due to osmoregulation in different salinity environments. The modified DEB model was validated with experimental data from different locations in the Western Baltic Sea (including the Limfjorden) with salinities varying from 8.5 to 29.9 psu. The identified areas suitable for mussel production in the Baltic Sea are located in the Little Belt area, the Great Belt, the southern Kattegat and the Limfjorden according to the prevailing salinity regimes. The new model can be used for supporting site selection of new mussel nutrient extraction cultures in the Baltic Sea that suffers from high eutrophication symptoms or as part of integrated multi-trophic aquaculture production. The model can also be used to predict the effects of salinity changes on mussel populations e.g. in climate change studies.

  11. A mineralogical record of ocean change: Decadal and centennial patterns in the California mussel.

    PubMed

    McCoy, Sophie J; Kamenos, Nicholas A; Chung, Peter; Wootton, Timothy J; Pfister, Catherine A

    2018-06-01

    Ocean acidification, a product of increasing atmospheric carbon dioxide, may already have affected calcified organisms in the coastal zone, such as bivalves and other shellfish. Understanding species' responses to climate change requires the context of long-term dynamics. This can be particularly difficult given the longevity of many important species in contrast with the relatively rapid onset of environmental changes. Here, we present a unique archival dataset of mussel shells from a locale with recent environmental monitoring and historical climate reconstructions. We compare shell structure and composition in modern mussels, mussels from the 1970s, and mussel shells dating back to 1000-2420 years BP. Shell mineralogy has changed dramatically over the past 15 years, despite evidence for consistent mineral structure in the California mussel, Mytilus californianus, over the prior 2500 years. We present evidence for increased disorder in the calcium carbonate shells of mussels and greater variability between individuals. These changes in the last decade contrast markedly from a background of consistent shell mineralogy for centuries. Our results use an archival record of natural specimens to provide centennial-scale context for altered minerology and variability in shell features as a response to acidification stress and illustrate the utility of long-term studies and archival records in global change ecology. Increased variability between individuals is an emerging pattern in climate change responses, which may equally expose the vulnerability of organisms and the potential of populations for resilience. © 2017 John Wiley & Sons Ltd.

  12. Expansion of Dreissena into offshore waters of Lake Michigan and potential impacts on fish populations

    USGS Publications Warehouse

    Bunnell, D.B.; Madenjian, C.P.; Holuszko, J.D.; Adams, J.V.; French, J. R. P.

    2009-01-01

    Lake Michigan was invaded by zebra mussels (Dreissena polymorpha) in the late 1980s and then followed by quagga mussels (D. bugensis) around 1997. Through 2000, both species (herein Dreissena) were largely restricted to depths less than 50??m. Herein, we provide results of an annual lake-wide bottom trawl survey in Lake Michigan that reveal the relative biomass and depth distribution of Dreissena between 1999 and 2007 (although biomass estimates from a bottom trawl are biased low). Lake-wide mean biomass density (g/m2) and mean depth of collection revealed no trend between 1999 and 2003 (mean = 0.7??g/m2 and 37??m, respectively). Between 2004 and 2007, however, mean lake-wide biomass density increased from 0.8??g/m2 to 7.0??g/m2, because of increased density at depths between 30 and 110??m, and mean depth of collection increased from 42 to 77??m. This pattern was confirmed by a generalized additive model. Coincident with the Dreissena expansion that occurred beginning in 2004, fish biomass density (generally planktivores) declined 71% between 2003 and 2007. Current understanding of fish population dynamics, however, indicates that Dreissena expansion is not the primary explanation for the decline of fish, and we provide a species-specific account for more likely underlying factors. Nonetheless, future sampling and research may reveal a better understanding of the potential negative interactions between Dreissena and fish in Lake Michigan and elsewhere.

  13. Evolutionary process of deep-sea bathymodiolus mussels.

    PubMed

    Miyazaki, Jun-Ichi; de Oliveira Martins, Leonardo; Fujita, Yuko; Matsumoto, Hiroto; Fujiwara, Yoshihiro

    2010-04-27

    Since the discovery of deep-sea chemosynthesis-based communities, much work has been done to clarify their organismal and environmental aspects. However, major topics remain to be resolved, including when and how organisms invade and adapt to deep-sea environments; whether strategies for invasion and adaptation are shared by different taxa or unique to each taxon; how organisms extend their distribution and diversity; and how they become isolated to speciate in continuous waters. Deep-sea mussels are one of the dominant organisms in chemosynthesis-based communities, thus investigations of their origin and evolution contribute to resolving questions about life in those communities. We investigated worldwide phylogenetic relationships of deep-sea Bathymodiolus mussels and their mytilid relatives by analyzing nucleotide sequences of the mitochondrial cytochrome c oxidase subunit I (COI) and NADH dehydrogenase subunit 4 (ND4) genes. Phylogenetic analysis of the concatenated sequence data showed that mussels of the subfamily Bathymodiolinae from vents and seeps were divided into four groups, and that mussels of the subfamily Modiolinae from sunken wood and whale carcasses assumed the outgroup position and shallow-water modioline mussels were positioned more distantly to the bathymodioline mussels. We provisionally hypothesized the evolutionary history of Bathymodilolus mussels by estimating evolutionary time under a relaxed molecular clock model. Diversification of bathymodioline mussels was initiated in the early Miocene, and subsequently diversification of the groups occurred in the early to middle Miocene. The phylogenetic relationships support the "Evolutionary stepping stone hypothesis," in which mytilid ancestors exploited sunken wood and whale carcasses in their progressive adaptation to deep-sea environments. This hypothesis is also supported by the evolutionary transition of symbiosis in that nutritional adaptation to the deep sea proceeded from extracellular

  14. Automatic detection of zebra crossings from mobile LiDAR data

    NASA Astrophysics Data System (ADS)

    Riveiro, B.; González-Jorge, H.; Martínez-Sánchez, J.; Díaz-Vilariño, L.; Arias, P.

    2015-07-01

    An algorithm for the automatic detection of zebra crossings from mobile LiDAR data is developed and tested to be applied for road management purposes. The algorithm consists of several subsequent processes starting with road segmentation by performing a curvature analysis for each laser cycle. Then, intensity images are created from the point cloud using rasterization techniques, in order to detect zebra crossing using the Standard Hough Transform and logical constrains. To optimize the results, image processing algorithms are applied to the intensity images from the point cloud. These algorithms include binarization to separate the painting area from the rest of the pavement, median filtering to avoid noisy points, and mathematical morphology to fill the gaps between the pixels in the border of white marks. Once the road marking is detected, its position is calculated. This information is valuable for inventorying purposes of road managers that use Geographic Information Systems. The performance of the algorithm has been evaluated over several mobile LiDAR strips accounting for a total of 30 zebra crossings. That test showed a completeness of 83%. Non-detected marks mainly come from painting deterioration of the zebra crossing or by occlusions in the point cloud produced by other vehicles on the road.

  15. Prevalence of Theileria equi and Babesia caballi as well as the identification of associated ticks in sympatric Grevy's zebras (Equus grevyi) and donkeys (Equus africanus asinus) in northern Kenya.

    PubMed

    Hawkins, Elaine; Kock, Richard; McKeever, Declan; Gakuya, Francis; Musyoki, Charles; Chege, Stephen M; Mutinda, Mathew; Kariuki, Edward; Davidson, Zeke; Low, Belinda; Skilton, Robert A; Njahira, Moses N; Wamalwa, Mark; Maina, Elsie

    2015-01-01

    The role of equine piroplasmosis as a factor in the population decline of the Grevy's zebra is not known. We determined the prevalence of Babesia caballi and Theileria equi in cograzing Grevy's zebras (Equus grevyi) and donkeys (Equus africanus asinus) in northern Kenya and identified the associated tick vectors. Blood samples were taken from 71 donkeys and 16 Grevy's zebras from March to May 2011. A nested PCR reaction using 18s ribosomal (r)RNA primers on 87 blood spots showed 72% (51/71; 95% confidence interval [CI] 60.4-81.0%) of donkeys and 100% (16/16; 95% CI, 77.3-100%) of Grevy's zebras were T. equi positive. No samples were positive for B. caballi. Sequence comparison using the National Center for Biotechnology Information's basic local alignment search tool identified homologous 18s rRNA sequences with a global geographic spread. The T. equi-derived sequences were evaluated using Bayesian approaches with independent Metropolis-coupled Markov chain Monte Carlo runs. The sequences clustered with those found in Sudan, Croatia, Mongolia, and the US, with statistical support greater than 80% for the two main clades. Hyalomma tick species were found on both donkeys and Grevy's zebras, whereas Rhipicephalus pulchellus was found exclusively on Grevy's zebras and Hyalomma marginatum rupfipes on donkeys. The prevalence of T. equi was 100% in Grevy's zebras and 72% in donkeys with common tick vectors identified. Our results suggest that donkeys and Grevy's zebras can be asymptomatic carriers and that piroplasmosis is endemic in the study area.

  16. LC-MS Analysis of Phenolic Compounds in Tubers Showing Zebra Chip Symptoms

    USDA-ARS?s Scientific Manuscript database

    A new potato disorder called zebra chip (ZC) has been identified in the United States and has been especially problematic in Texas where substantial economic losses have been incurred. Upon frying, ZC tubers develop a dark “zebra chip” pattern of discoloration. LC-MS analysis of symptomatic tubers...

  17. Large-scale synchronization of annual recruitment success and stock size in Wadden Sea populations of the mussel Mytilus edulis L.

    NASA Astrophysics Data System (ADS)

    Beukema, J. J.; Dekker, R.; van Stralen, M. R.; de Vlas, J.

    2015-12-01

    Simultaneous abundance or shortage of mussels over vast areas may seriously affect fishery as well as shellfish-eating birds. We studied synchrony in annual recruit numbers and stock sizes (biomass) of mussels on the base of long-term observations in various parts of the Dutch (and German) Wadden Sea, including regular monitoring on Balgzand (a 50-km2 tidal flat area) and published or unpublished records for other parts of the Wadden Sea. Annual records for 37 years of mussel seed abundance in the eastern and western half of the Dutch Wadden Sea proved to be mutually well correlated and were also significantly correlated with annually assessed numerical densities of mussel recruits on Balgzand. The scarce long-term series available on mussel biomass pointed to significantly positive correlations between stock sizes on Balgzand and those in the northern German Wadden Sea, at about 300 km distance. The incidence of severe winters, which occurrence is synchronized over areas in the order of thousands of km, is identified as the dominant causative factor behind Wadden Sea-wide recruitment synchrony. Severe winters are known to reduce abundance of predators on tiny bivalve spat, and this process may overrule local processes causing abundance variation in bivalves. As such extreme winters are infrequent (usually only one or two per decade), sensible studies on the phenomenon of synchronization in abundance of Wadden Sea bivalves should be based on data series of sufficient length, covering decades.

  18. ZebraZoom: an automated program for high-throughput behavioral analysis and categorization

    PubMed Central

    Mirat, Olivier; Sternberg, Jenna R.; Severi, Kristen E.; Wyart, Claire

    2013-01-01

    The zebrafish larva stands out as an emergent model organism for translational studies involving gene or drug screening thanks to its size, genetics, and permeability. At the larval stage, locomotion occurs in short episodes punctuated by periods of rest. Although phenotyping behavior is a key component of large-scale screens, it has not yet been automated in this model system. We developed ZebraZoom, a program to automatically track larvae and identify maneuvers for many animals performing discrete movements. Our program detects each episodic movement and extracts large-scale statistics on motor patterns to produce a quantification of the locomotor repertoire. We used ZebraZoom to identify motor defects induced by a glycinergic receptor antagonist. The analysis of the blind mutant atoh7 revealed small locomotor defects associated with the mutation. Using multiclass supervised machine learning, ZebraZoom categorized all episodes of movement for each larva into one of three possible maneuvers: slow forward swim, routine turn, and escape. ZebraZoom reached 91% accuracy for categorization of stereotypical maneuvers that four independent experimenters unanimously identified. For all maneuvers in the data set, ZebraZoom agreed with four experimenters in 73.2–82.5% of cases. We modeled the series of maneuvers performed by larvae as Markov chains and observed that larvae often repeated the same maneuvers within a group. When analyzing subsequent maneuvers performed by different larvae, we found that larva–larva interactions occurred as series of escapes. Overall, ZebraZoom reached the level of precision found in manual analysis but accomplished tasks in a high-throughput format necessary for large screens. PMID:23781175

  19. Mussel-Inspired Adhesives and Coatings

    PubMed Central

    Lee, Bruce P.; Messersmith, P.B.; Israelachvili, J.N.; Waite, J.H.

    2011-01-01

    Mussels attach to solid surfaces in the sea. Their adhesion must be rapid, strong, and tough, or else they will be dislodged and dashed to pieces by the next incoming wave. Given the dearth of synthetic adhesives for wet polar surfaces, much effort has been directed to characterizing and mimicking essential features of the adhesive chemistry practiced by mussels. Studies of these organisms have uncovered important adaptive strategies that help to circumvent the high dielectric and solvation properties of water that typically frustrate adhesion. In a chemical vein, the adhesive proteins of mussels are heavily decorated with Dopa, a catecholic functionality. Various synthetic polymers have been functionalized with catechols to provide diverse adhesive, sealant, coating, and anchoring properties, particularly for critical biomedical applications. PMID:22058660

  20. Transformation of temporal sequences in the zebra finch auditory system

    PubMed Central

    Lim, Yoonseob; Lagoy, Ryan; Shinn-Cunningham, Barbara G; Gardner, Timothy J

    2016-01-01

    This study examines how temporally patterned stimuli are transformed as they propagate from primary to secondary zones in the thalamorecipient auditory pallium in zebra finches. Using a new class of synthetic click stimuli, we find a robust mapping from temporal sequences in the primary zone to distinct population vectors in secondary auditory areas. We tested whether songbirds could discriminate synthetic click sequences in an operant setup and found that a robust behavioral discrimination is present for click sequences composed of intervals ranging from 11 ms to 40 ms, but breaks down for stimuli composed of longer inter-click intervals. This work suggests that the analog of the songbird auditory cortex transforms temporal patterns to sequence-selective population responses or ‘spatial codes', and that these distinct population responses contribute to behavioral discrimination of temporally complex sounds. DOI: http://dx.doi.org/10.7554/eLife.18205.001 PMID:27897971

  1. Effects of low and high salinity regimes on seasonal gametogenesis of the ribbed mussel Geukensia granosissima in coastal Louisiana, USA

    USGS Publications Warehouse

    Honig, Aaron; LaPeyre, Megan K.; Supan, John

    2014-01-01

    Benthic intertidal bivalves play an essential role in estuarine ecosystems by contributing to habitat provision, water filtration, and host vegetation productivity. As such, ecosystem level changes that impact population distributions and persistence of local bivalve populations may have large ecosystem level consequences, making it important to better understand the population ecology of native bivalves. In order to determine potential impacts of shifting salinity and temperature regimes along the northern Gulf of Mexico, the seasonal timing of gametogenesis in the Gulf estuarine ribbed mussel, Geukensia granossisima, was examined across a salinity gradient in southeastern Louisiana, from July 2011 through October 2012. Ten mussels were randomly sampled monthly from low (~ 5) and high (~25) salinity marsh sites in southeastern Louisiana, and histologically processed to determine the seasonal progression of gametogenesis. Peak ripeness occurred at both sites between April and September, was positively correlated with temperature, and coincided with seasonal shifts in salinity. Mussels located in lower salinity waters demonstrated a shorter period of gametogenesis, and lower rates of ripeness indicating that changes in salinity regimes may impact long-term population dynamics.

  2. Selective auditory grouping by zebra finches: testing the iambic-trochaic law.

    PubMed

    Spierings, Michelle; Hubert, Jeroen; Ten Cate, Carel

    2017-07-01

    Humans have a strong tendency to spontaneously group visual or auditory stimuli together in larger patterns. One of these perceptual grouping biases is formulated as the iambic/trochaic law, where humans group successive tones alternating in pitch and intensity as trochees (high-low and loud-soft) and alternating in duration as iambs (short-long). The grouping of alternations in pitch and intensity into trochees is a human universal and is also present in one non-human animal species, rats. The perceptual grouping of sounds alternating in duration seems to be affected by native language in humans and has so far not been found among animals. In the current study, we explore to which extent these perceptual biases are present in a songbird, the zebra finch. Zebra finches were trained to discriminate between short strings of pure tones organized as iambs and as trochees. One group received tones that alternated in pitch, a second group heard tones alternating in duration, and for a third group, tones alternated in intensity. Those zebra finches that showed sustained correct discrimination were next tested with longer, ambiguous strings of alternating sounds. The zebra finches in the pitch condition categorized ambiguous strings of alternating tones as trochees, similar to humans. However, most of the zebra finches in the duration and intensity condition did not learn to discriminate between training stimuli organized as iambs and trochees. This study shows that the perceptual bias to group tones alternating in pitch as trochees is not specific to humans and rats, but may be more widespread among animals.

  3. New environmentally friendly MSPD solid support based on golden mussel shell: characterization and application for extraction of organic contaminants from mussel tissue.

    PubMed

    Rombaldi, Caroline; de Oliveira Arias, Jean Lucas; Hertzog, Gabriel Ianzer; Caldas, Sergiane Souza; Vieira, João P; Primel, Ednei Gilberto

    2015-06-01

    The use of golden mussel shells as a solid support in vortex-assisted matrix solid-phase dispersion (MSPD) was evaluated for the first time for extraction of residues of 11 pesticides and nine pharmaceutical and personal care products from mussel tissue samples. After they had been washed, dried, and milled, the mussel shells were characterized by scanning electron microscopy, energy-dispersive X-ray spectroscopy, infrared spectroscopy, and Brunauer-Emmett-Teller analysis. The MSPD procedure with analysis by liquid chromatography-tandem mass spectrometry allowed the determination of target analytes at trace concentrations (nanograms per gram), with mean recoveries ranging from 61 to 107 % and relative standard deviations lower than 18 %. The optimized method consisted of dispersion of 0.5 g of mussel tissue, 0.5 g of NaSO4, and 0.5 g of golden mussel shell for 5 min, and subsequent extraction with 5 mL of ethyl acetate. The matrix effect was evaluated, and a low effect was found for all compounds. The results showed that mussel shell is an effective material and a less expensive material than materials that have traditionally been used, i.e., it may be used in the MSPD dispersion step during the extraction of pesticides and pharmaceutical and personal care products from golden mussel tissues. Graphical Abstract Vortex-assited matrix solid-phase dispersion for extraction of 11 pesticides and 9 PPCPs care products from mussel tissue samples.

  4. The Effect on Selenium Concentrations of a Randomized Intervention with Fish and Mussels in a Population with Relatively Low Habitual Dietary Selenium Intake

    PubMed Central

    Outzen, Malene; Tjønneland, Anne; Larsen, Erik H.; Andersen, Klaus K.; Christensen, Jane; Overvad, Kim; Olsen, Anja

    2015-01-01

    Selenium status of the Danish population is below that assumed optimal for the suggested protective effects against chronic diseases, including certain cancers. Fish and shellfish are important dietary sources of selenium in Denmark. We investigated the effect of increased fish and mussel intake on selenium blood concentrations in a population with relatively low habitual dietary selenium intake. We randomly assigned 102 healthy men and women (all non-smokers) aged 48–76 years to an intervention group (n = 51) or a control group (n = 51). Intervention participants received 1000 g fish and mussels/week for 26 weeks (~50 μg selenium/day). Controls received no intervention. Non-fasting blood samples were taken and whole blood selenium was determined using inductively coupled plasma-mass spectrometry (ICP-MS), and plasma selenoprotein P (SelP) was determined by high performance liquid chromatography coupled to ICP-MS. All available observations were included in linear multiple regression analysis to evaluate the effect of the intervention. The difference in mean change for intervention compared with control persons was 14.9 ng/mL (95% CI: 10.2, 19.7) for whole blood selenium, and 7.0 ng/mL (95% CI: 3.1, 10.9) for plasma SelP (Weeks 0–26). Selenium concentrations were significantly increased after 26 weeks of intervention, albeit to a lower degree than expected. PMID:25599275

  5. Dissection and Downstream Analysis of Zebra Finch Embryos at Early Stages of Development

    PubMed Central

    Murray, Jessica R.; Stanciauskas, Monika E.; Aralere, Tejas S.; Saha, Margaret S.

    2014-01-01

    The zebra finch (Taeniopygiaguttata) has become an increasingly important model organism in many areas of research including toxicology1,2, behavior3, and memory and learning4,5,6. As the only songbird with a sequenced genome, the zebra finch has great potential for use in developmental studies; however, the early stages of zebra finch development have not been well studied. Lack of research in zebra finch development can be attributed to the difficulty of dissecting the small egg and embryo. The following dissection method minimizes embryonic tissue damage, which allows for investigation of morphology and gene expression at all stages of embryonic development. This permits both bright field and fluorescence quality imaging of embryos, use in molecular procedures such as in situ hybridization (ISH), cell proliferation assays, and RNA extraction for quantitative assays such as quantitative real-time PCR (qtRT-PCR). This technique allows investigators to study early stages of development that were previously difficult to access. PMID:24999108

  6. Acute sensitivity of a broad range of freshwater mussels to chemicals with different modes of toxic action

    USGS Publications Warehouse

    Wang, Ning; Ivey, Chris D.; Ingersoll, Christopher G.; Brumbaugh, William G.; Alvarez, David; Hammer, Edward J.; Bauer, Candice R.; Augspurger, Tom; Raimondo, Sandy; Barnhart, M.Christopher

    2017-01-01

    Freshwater mussels, one of the most imperiled groups of animals in the world, are generally underrepresented in toxicity databases used for the development of ambient water quality criteria and other environmental guidance values. Acute 96-h toxicity tests were conducted to evaluate the sensitivity of 5 species of juvenile mussels from 2 families and 4 tribes to 10 chemicals (ammonia, metals, major ions, and organic compounds) and to screen 10 additional chemicals (mainly organic compounds) with a commonly tested mussel species, fatmucket (Lampsilis siliquoidea). In the multi-species study, median effect concentrations (EC50s) among the 5 species differed by a factor of ≤2 for chloride, potassium, sulfate, and zinc; a factor of ≤5 for ammonia, chromium, copper, and nickel; and factors of 6 and 12 for metolachlor and alachlor, respectively, indicating that mussels representing different families or tribes had similar sensitivity to most of the tested chemicals, regardless of modes of action. There was a strong linear relationship between EC50s for fatmucket and the other 4 mussel species across the 10 chemicals (r2 = 0.97, slope close to 1.0), indicating that fatmucket was similar to other mussel species; thus, this commonly tested species can be a good surrogate for protecting other mussels in acute exposures. The sensitivity of juvenile fatmucket among different populations or cultured from larvae of wild adults and captive-cultured adults was also similar in acute exposures to copper or chloride, indicating captive-cultured adult mussels can reliably be used to reproduce juveniles for toxicity testing. In compiled databases for all freshwater species, 1 or more mussel species were among the 4 most sensitive species for alachlor, ammonia, chloride, potassium, sulfate, copper, nickel, and zinc; therefore, the development of water quality criteria and other environmental guidance values for these chemicals should reflect the sensitivity of mussels. In

  7. Native Mussels Alter Nutrient Availability and Reduce Blue ...

    EPA Pesticide Factsheets

    Nutrient cycling is a key process that ties all organisms together. This is especially apparent in stream environments in which nutrients are taken up readily and cycled through the system in a downstream trajectory. Ecological stoichiometry predicts that biogeochemical cycles of different elements are interdependent because the organisms that drive these cycles require fixed ratios of nutrients. There is growing recognition that animals play an important role in biogeochemical cycling across ecosystems. In particular, dense aggregations of consumers can create biogeochemical hotspots in aquatic ecosystems via nutrient translocation. We predicted that filter-feeding freshwater mussels, which occur as speciose, high biomass aggregates, would create biogeochemical hotspots in streams by altering nutrient limitation and algal dynamics. In a field study, we manipulated nitrogen and phosphorus using nutrient-diffusing substrates in areas with high and low mussel abundance, recorded algal growth and community composition, and determined in situ mussel excretion stoichiometry at 18 sites in 3 rivers (Kiamichi, Little, and Mt. Fork rivers, southcentral U.S.). Our results indicate that mussels greatly influence ecosystem processes by modifying the nutrients that limit primary productivity. Sites without mussels were N-limited with ~26% higher abundances of N-fixing blue-green algae, while sites with high mussel densities were co-limited (N and P) and dominated by diatoms

  8. Assessment of the Particulate Food Supply Available for Mussel ( Mytilus spp.) Farming in a Semi-enclosed, Northern Inlet

    NASA Astrophysics Data System (ADS)

    Penney, R. W.; McKenzie, C. H.; Mills, T. J.

    2001-07-01

    Temporal variability in the quantity, organic content, and phytoplankton composition of the particulate food supply available to a cultured mussel population was assessed for a 3-year period in a small inlet of Notre Dame Bay, Newfoundland, Canada. The study site had a restricted flushing rate estimated at 1-2·75 times wk -1for a complete water exchange. The quantity of both total (TPM) and organic (POM) seston varied temporally from 0·7-23·7 mg l -1and 0·05-1·97 mg l -1respectively during the 3-year sampling period. TPM typically remained relatively high (>10 mg l -1) through the winter and spring period. Most of the seasonal variation in total seston was due to seasonal variability in the PIM component. Both PIM and POM concentrations were seasonally lowest during summer. The organic fraction of the seston (POM/TPM ratio) was seasonally low in winter and increased steadily through spring and summer to reach its maximum in the autumn. The living phytoplankton component of the seston was typically dominated, both numerically and in biomass, by a variety of diatom and autotrophic nanoflagellate species in the 2- 20-μm diameter size range. Discrete diatom population blooms occurred in the autumn of all three years and largely consisted of a single species, Skeletonema costatum. Phytoplankton:detritus ratios were significantly lower during winter. Total phytoplankton biomass levels were seasonally low during winter and summer and were associated with seasonal variation in diatom biomass. We conducted modelling simulations of relationships among seston organic food levels, their temporal variability, tidal flushing rates, cultured mussel biomass and production indices, and estimates of mussel maintenance ration requirements to predict the adequacy of northern inlets to sustain commercial-scale mussel farm development. We conclude from these simulations that small, semi-enclosed, northern inlets likely frequently experience periods when naturally occurring organic

  9. Development and evaluation of a boat-mounted RFID antenna for monitoring freshwater mussels

    USGS Publications Warehouse

    Fischer, Jesse R.; Neebling, Travis E.; Quist, Michael C.

    2012-01-01

    Development of radio frequency identification (RFID) technology and passive integrated transponder (PIT) tags has substantially increased the ability of researchers and managers to monitor populations of aquatic organisms. However, use of transportable RFID antenna systems (i.e., backpack-mounted) is currently limited to wadeable aquatic environments (<1.4 m water depth). We describe the design, construction, and evaluation of a boat-mounted RFID antenna to detect individually PIT-tagged benthic aquatic organisms (mussels). We evaluated the effects of tag orientation on detection distances in water with a 32-mm half-duplex PIT tag. Detection distances up to 50 cm from the antenna coils were obtained, but detection distance was dependent on tag orientation. We also evaluated detection distance of PIT tags beneath the sediment to simulate detection of burrowing mussels with 23- and 32-mm tags. In sand substrate, the maximum detection distance varied from 3.5 cm and 4.5 cm (vertical tag orientation) to 24.7 cm and 39.4 cm (45° tag orientation) for the 23- and 32-mm PIT tags, respectively. Our results suggest a 1.4-m total detection width for tagged mussels on the substrate surface by the boat-mounted antenna system regardless of tag orientation. However, burrowed mussels may require multiple passes to increase detection that would be influenced by depth, tag orientation, and tag size. Construction of the boat-mounted antenna was relatively low in cost (<500 USD) and had several advantages (less labor and time intensive, increased safety) over traditional mussel sampling techniques (diving, snorkeling) in nonwadeable habitats.

  10. Zebra Mussel Chemical Control Guide.

    DTIC Science & Technology

    2000-01-01

    References 80 Aromatic Hydrocarbons 82 BULAB6009 82 Chemical Name and Formulations 82 Mode of Action 82 Application Strategies 82 Timing of Application...organisms once they are bound to anionic substances (Dobbs et al. 1995). b. Aromatic hydrocarbons . Compounds such as BULAB® 6009 and MEXEL 432™ also...Pallas): A new mollusc in the Great Lakes," Can. J. FishAquat. Sei. 46, 1587-1591. Heitanen, E. (1997). "Toxicity testing of Endod, a natural

  11. Recovery of a fish pathogenic bacterium, Aeromonas salmonicida, from ebonyshell mussels Fusconaia ebena using nondestructive sample collection procedures

    USGS Publications Warehouse

    Starliper, C.E.

    2008-01-01

    Refugia are increasingly being used to maintain and propagate imperiled freshwater mussels for future population augmentations. Success for this endeavor is dependent on good husbandry, including a holistic program of resource health management. A significant aspect to optimal health is the prevention or control of infectious diseases. Describing and monitoring pathogens and diseases in mussels involves examination of tissues or samples collected from an appropriate number of individuals that satisfies a certain confidence level for expected prevalences of infections. In the present study, ebonyshell mussels Fusconaia ebena were infected with a fish pathogenic bacterium, Aeromonas salmonicida, through their cohabitation with diseased brook trout Salvelinus fontinalis. At a 100% prevalence of infection, the F. ebena were removed from the cohabitation tank to clean tanks that were supplied with pathogen-free water, which initiated their depuration of A. salmonicida. Three samples (nondestructive fluid, mantle, hemolymph) collected using nondestructive procedures were compared with fluids and soft tissue homogenates collected after sacrificing the mussels for recovery of the bacterium during this period of depuration. Nondestructive sample collections, especially ND fluid, provide a comparable alternative to sacrificing mussels to determine pathogen status.

  12. Impact of the Sea Empress oil spill on lysosomal stability in mussel blood cells.

    PubMed

    Fernley, P W; Moore, M N; Lowe, D M; Donkin, P; Evans, S

    2000-01-01

    Coastal zones are among the most productive and vulnerable areas on the planet. An example of impact on these fragile environments was shown in the case of the "Sea Empress" oil tanker, which ran aground in the Bristol Channel in 1996, spilling 72,000 tons of "Forties" crude oil. The objective was to investigate the sub-lethal cellular pathology and tissue hydrocarbon contamination in marine mussel populations, 4 months after the initial spill, using the neutral red retention (NRR) assay for lysosomal stability in blood cells. NRR was reduced in mussels, and indicative of cell injury, from the two sites closest to the spill in comparison with more distant and reference sites. Lysosomal stability was inversely correlated with polycyclic aromatic hydrocarbon concentrations in mussel tissues. Reduced lysosomal stability has previously been shown to contribute to impaired immunocompetence and to autophagic loss of body tissues. The use of this type of technique is discussed in the context of cost-effective, ecotoxicological tools for Integrated Coastal Zone Management.

  13. Mussel watch

    NASA Astrophysics Data System (ADS)

    Contamination of U.S. coastal areas may be decreasing as a result of environmental regulations that have banned or curtailed toxic chemicals, concludes a report by the National Oceanic and Atmospheric Administration. The report, “Recent Trends in Coastal Environmental Quality: Results from the Mussel Watch Project,” presents results of analyzing chemical concentrations found in mussel and oyster tissues collected every year since 1986.These mollusks are collected once a year at more than 240 sites nationwide and analyzed for over 70 polycyclic aromatic hydrocarbons, polychlorinated biphenyls, chlorinated pesticides, butyltins, and toxic trace elements such as copper, cadmium, and lead. The report states that from 1986 to 1993 there were many more decreases than increases in chemical concentrations in coastal regions. These decreasing trends were not unexpected; all of the monitored chlorinated hydrocarbons have been banned for use in the United States, and tributyltin has been banned as a biocide on recreational boats.

  14. Naturally acidified habitat selects for ocean acidification–tolerant mussels

    PubMed Central

    Thomsen, Jörn; Stapp, Laura S.; Haynert, Kristin; Schade, Hanna; Danelli, Maria; Lannig, Gisela; Wegner, K. Mathias; Melzner, Frank

    2017-01-01

    Ocean acidification severely affects bivalves, especially their larval stages. Consequently, the fate of this ecologically and economically important group depends on the capacity and rate of evolutionary adaptation to altered ocean carbonate chemistry. We document successful settlement of wild mussel larvae (Mytilus edulis) in a periodically CO2-enriched habitat. The larval fitness of the population originating from the CO2-enriched habitat was compared to the response of a population from a nonenriched habitat in a common garden experiment. The high CO2–adapted population showed higher fitness under elevated Pco2 (partial pressure of CO2) than the non-adapted cohort, demonstrating, for the first time, an evolutionary response of a natural mussel population to ocean acidification. To assess the rate of adaptation, we performed a selection experiment over three generations. CO2 tolerance differed substantially between the families within the F1 generation, and survival was drastically decreased in the highest, yet realistic, Pco2 treatment. Selection of CO2-tolerant F1 animals resulted in higher calcification performance of F2 larvae during early shell formation but did not improve overall survival. Our results thus reveal significant short-term selective responses of traits directly affected by ocean acidification and long-term adaptation potential in a key bivalve species. Because immediate response to selection did not directly translate into increased fitness, multigenerational studies need to take into consideration the multivariate nature of selection acting in natural habitats. Combinations of short-term selection with long-term adaptation in populations from CO2-enriched versus nonenriched natural habitats represent promising approaches for estimating adaptive potential of organisms facing global change. PMID:28508039

  15. Naturally acidified habitat selects for ocean acidification-tolerant mussels.

    PubMed

    Thomsen, Jörn; Stapp, Laura S; Haynert, Kristin; Schade, Hanna; Danelli, Maria; Lannig, Gisela; Wegner, K Mathias; Melzner, Frank

    2017-04-01

    Ocean acidification severely affects bivalves, especially their larval stages. Consequently, the fate of this ecologically and economically important group depends on the capacity and rate of evolutionary adaptation to altered ocean carbonate chemistry. We document successful settlement of wild mussel larvae ( Mytilus edulis ) in a periodically CO 2 -enriched habitat. The larval fitness of the population originating from the CO 2 -enriched habitat was compared to the response of a population from a nonenriched habitat in a common garden experiment. The high CO 2 -adapted population showed higher fitness under elevated P co 2 (partial pressure of CO 2 ) than the non-adapted cohort, demonstrating, for the first time, an evolutionary response of a natural mussel population to ocean acidification. To assess the rate of adaptation, we performed a selection experiment over three generations. CO 2 tolerance differed substantially between the families within the F 1 generation, and survival was drastically decreased in the highest, yet realistic, P co 2 treatment. Selection of CO 2 -tolerant F 1 animals resulted in higher calcification performance of F 2 larvae during early shell formation but did not improve overall survival. Our results thus reveal significant short-term selective responses of traits directly affected by ocean acidification and long-term adaptation potential in a key bivalve species. Because immediate response to selection did not directly translate into increased fitness, multigenerational studies need to take into consideration the multivariate nature of selection acting in natural habitats. Combinations of short-term selection with long-term adaptation in populations from CO 2 -enriched versus nonenriched natural habitats represent promising approaches for estimating adaptive potential of organisms facing global change.

  16. The existence of microplastic in Asian green mussels

    NASA Astrophysics Data System (ADS)

    Khoironi, A.; Anggoro, S.; Sudarno

    2018-03-01

    Due to resistance of polymer as basic properties of plastic, several studies have been conducted to understand the fate of plastic debris in the marine environment. Degradation is the most important process to control distribution of plastic debris a long the marine environment until the existence of plastic in the food chain. The physical and chemical changes of plastic because of degradation process will lead to the release of polluted substances which eventually more toxic for the environment. Furthermore, when plastic degraded become a microplastic will lead to easy ingested by biotic such as mussell which commonly consumed by humans. The aim of this research was to investigate the concentration of microplastic adsorbed and ingested by mussels considering characteristic of sea water. About 30 samples have been collected from 3 different locations that is brackish water (31 ppb), high salinity (36 ppb) and low salinity (33 ppb) for measuring a number of microplastic in mussels on three different salinity. The result of microstructure analysis by microscope showed that mussel evaluated from the marine environment contaminated by microplastic with average size of 211.163 μm. In high salinity sea water, microplastic found in mussel was greater than low salinity and brackish water. The SEM/EDX analysis showed the presence of SIO2 0.14 % (w/w), Na2O 24.27 %(w/w) and Al2O3 0.27 % (w/w) in the microplastic obtained in the mussel indicating the components which are mostly found in the plastic industries. The amount of microplastic in mussell could be used as pollution indicator in the marine environmental by plastic waste.

  17. Prehistoric decline in freshwater mussels coincident with the advent of maize agriculture

    Treesearch

    Evan Peacock; Wendell Haag; Melvin Warren

    2005-01-01

    During late prehistory, high population densities and intensive agricultural practices of Native American societies had profound effects on the pre-Columbian landscape. The degree to which Native American land use affected aquatic ecosystems is unknown. Freshwater mussels are particularly sensitive harbingers of modern-day ecosystem deterioration.We used data from...

  18. Heart Rate Sensor for Freshwater Mussels

    NASA Astrophysics Data System (ADS)

    Just, C. L.; Vial, D. P.; Kruger, A.; Niemeier, J. J.; Lee, H. W.; Schroer, H. W.

    2014-12-01

    Researchers have long been interested the cardiac activity of mollusks. First, it is important as a basic measure of the animal's metabolism. Further, activities such as feeding and burrowing affect heart rate, as do environmental factors such as water salinity, water temperature, exposure, and predation. We have developed a small, noninvasive sensor for measuring freshwater mussel heart rate. Its working principle is as follows. An infrared (IR) light-emitting diode is placed in contact with the mussel shell. Some of the IR penetrates through the shell, reflects off internal organs, and traverses back. A photodetector detects this IR, and electronics condition the signal. The heartbeat of the animal modulates the IR, allowing one to measure the heart rate. The technique is widely-used in finger heart-rate monitors in humans. The sensors do not have to be positioned above the heart and several locations on the mussel shell work well. The sensor is small (8 mm × 10 mm) and consumes less than 1 mA, and has a simple one-wire interface that allows for easy integration into data acquisition hardware. We present heart rate measurements for the common pocketbook (lampsilis cardium) freshwater mussel.

  19. Effects of metal pollution on genetics of freshwater mussels in a southeastern Missouri mining district

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Young, M.Y.

    Lead mining has historically been in operation in Missouri since the 1700`s, and an extensively mineralized region known as the ``Old Lead Belt`` in the southeastern portion of the state contained some of the most substantial deposits in the district. Although mining is currently inactive in this region, intensive past mining resulted in accumulation of large tailings piles placed adjacent to aquatic resources. Erosion and accidental releases of mine tailings rich in lead, zinc, cadmium and copper have resulted in contamination in the Big River drainage, one of two principal tributaries in the Meramec River Basin. Substantial bioaccumulation of metalsmore » has previously been documented for freshwater mussels collected from the Big River, as well as for other aquatic biota. This research project investigated the effects of metal pollution on biochemical genetic variability among three populations of the freshwater mussel Lampsilis ventricosa in the Meramec River Basin. Specimens were collected from metal-contaminated reaches of the Big River, and two reference populations in Meramec and Bourbeuse Rivers. Using techniques of starch gel electrophoresis, significant differences were found in allozyme frequencies at the phosphoglucomutase locus between mussels collected from the metal-contaminated Big River versus reference populations, suggesting that certain allozyme genotypes may be more sensitive than others to metal pollutants. The genetic response to geographic variation in environmental contamination between the L. ventricosa populations examined in the Meramec River Basin suggests that differential pollution-induced selection of allozyme genotypes has occurred in the Big River.« less

  20. Ninespine Stickleback Abundance in Lake Michigan Increases After Dreissenid Mussel Invasion

    USGS Publications Warehouse

    Madenjian, Charles P.; Bunnell, David B.; Gorman, Owen T.

    2010-01-01

    Based on data from our annual lakewide bottom trawl survey of Lake Michigan, we determined that density of ninespine sticklebacks Pungitius pungitius increased from an average of 0.234 kg/ha during 1973–1995 to an average of 1.318 kg/ha during 1996–2007. This greater-than-fivefold increase in density coincided with the dreissenid mussel invasion of Lake Michigan. Intervention analysis revealed that ninespine stickleback density in Lake Michigan significantly increased between the two time periods. In contrast, based on data from our annual bottom trawl survey of U.S. waters of Lake Superior, ninespine stickleback density decreased from an average of 0.133 kg/ha during 1978–1999 to an average of only 0.026 kg/ha during 2000–2007. This greater-than-fivefold density decrease, which was found to be significant via intervention analysis, coincided with population recovery for both lean and fat morphotypes of lake trout Salvelinus namaycush in Lake Superior. In contrast to Lake Michigan, dreissenid mussels have not invaded Lake Superior on a lakewide basis. Thus, a comparison of these two lakes indicated that the increase in ninespine stickleback abundance in Lake Michigan was most likely attributable to the dreissenid mussel invasion. In addition, based on our correlation analysis, alewives Alosa pseudoharengus did not have an adverse effect on ninespine stickleback abundance in Lake Michigan. Perhaps the recent increase in biomass of green algae Cladophora spp. associated with the dreissenid mussel invasion improved spawning habitat quality for ninespine sticklebacks and led to their stepwise abundance increase in Lake Michigan beginning in 1996

  1. Potential environmental drivers of a regional blue mussel mass mortality event (winter of 2014, Breton Sound, France)

    NASA Astrophysics Data System (ADS)

    Polsenaere, Pierre; Soletchnik, Patrick; Le Moine, Olivier; Gohin, Francis; Robert, Stéphane; Pépin, Jean-François; Stanisière, Jean-Yves; Dumas, Franck; Béchemin, Christian; Goulletquer, Philippe

    2017-05-01

    In the context of global change, increasing mariculture production has raised particular concerns regarding its environmental impact and sustainability. Molluscs and particularly blue mussel account for a significant part of this total production. Although blue mussels are considered to be pretty resilient to environmental disturbances, we report in this study an unprecedented mussel mortality event that occurred during the winter of 2014 in the Breton Sound. 9000 metric tonnes of mussels were lost and mortality rates up to 100% were recorded at some farming areas. Through a coupling approach, the present work aims to better understand the potential environmental drivers associated with those mortalities. Firstly, we analysed long-term in situ and satellite data from environmental monitoring networks (available since 1998) to characterize the variability of seawater masses of the sound during the winter of 2014. Secondly, we used modelling simulations to study the possible relationship between seawater hydrodynamics and observed spatio-temporal patterns of mussel mortalities. From January to April 2014 at the long-line culture site where mortalities started, seawater temperatures ranged from 8.3 to 13.3 °C (10.2 ± 0.8 °C). Salinity and turbidity values showed successive and short drops (below 16; 29.3 ± 2.3) and numerous peaks (above 70 NTU; 17.4 ± 13.4 NTU) respectively. Winter conditions of 2014 were encountered along the entire French Atlantic coastline and linked to the sixth highest positive North Atlantic Oscillation (NAO +) index recorded since 1865. These particular environmental variations characterized the winter of 2014 but also others whereas no comparable mussel mortality rates were reported. Exact causes of the 2014 mortality event are still unknown but we showed these environmental variations could not alone be responsible. These have likely affected the sensitivity of the blue mussel populations that were already weakened by early spawning

  2. The disassociation of visual and acoustic conspecific cues decreases discrimination by female zebra finches (Taeniopygia guttata).

    PubMed

    Campbell, Dana L M; Hauber, Mark E

    2009-08-01

    Female zebra finches (Taeniopygia guttata) use visual and acoustic traits for accurate recognition of male conspecifics. Evidence from video playbacks confirms that both sensory modalities are important for conspecific and species discrimination, but experimental evidence of the individual roles of these cue types affecting live conspecific recognition is limited. In a spatial paradigm to test discrimination, the authors used live male zebra finch stimuli of 2 color morphs, wild-type (conspecific) and white with a painted black beak (foreign), producing 1 of 2 vocalization types: songs and calls learned from zebra finch parents (conspecific) or cross-fostered songs and calls learned from Bengalese finch (Lonchura striata vars. domestica) foster parents (foreign). The authors found that female zebra finches consistently preferred males with conspecific visual and acoustic cues over males with foreign cues, but did not discriminate when the conspecific and foreign visual and acoustic cues were mismatched. These results indicate the importance of both visual and acoustic features for female zebra finches when discriminating between live conspecific males. Copyright 2009 APA, all rights reserved.

  3. Acoustic fine structure may encode biologically relevant information for zebra finches.

    PubMed

    Prior, Nora H; Smith, Edward; Lawson, Shelby; Ball, Gregory F; Dooling, Robert J

    2018-04-18

    The ability to discriminate changes in the fine structure of complex sounds is well developed in birds. However, the precise limit of this discrimination ability and how it is used in the context of natural communication remains unclear. Here we describe natural variability in acoustic fine structure of male and female zebra finch calls. Results from psychoacoustic experiments demonstrate that zebra finches are able to discriminate extremely small differences in fine structure, which are on the order of the variation in acoustic fine structure that is present in their vocal signals. Results from signal analysis methods also suggest that acoustic fine structure may carry information that distinguishes between biologically relevant categories including sex, call type and individual identity. Combined, our results are consistent with the hypothesis that zebra finches can encode biologically relevant information within the fine structure of their calls. This study provides a foundation for our understanding of how acoustic fine structure may be involved in animal communication.

  4. Susceptibility and antibody response of the laboratory model zebra finch (Taeniopygia guttata) to West Nile Virus

    USGS Publications Warehouse

    Hofmeister, Erik K.; Lund, Melissa; Shearn-Bochsler, Valerie I.; Balakrishnan, Christopher N.

    2017-01-01

    Since the introduction of West Nile virus (WNV) into North America in 1999 a number of passerine bird species have been found to play a role in the amplification of the virus. Arbovirus surveillance, observational studies and experimental studies have implicated passerine birds (songbirds, e.g., crows, American robins, house sparrows, and house finches) as significant reservoirs of WNV in North America, yet we lack a tractable passerine animal model for controlled studies of the virus. The zebra finch (Taeniopygia guttata) serves as a model system across a diversity of fields, and here we develop the zebra finch a songbird model for WNV. Like many natural hosts of WNV, we found that zebra finches developed sufficient viremia to serve as a competent host, yet in general resisted mortality from infection. In the Australian zebra finch (AZF) T. g. castanotis, we detected WNV in the majority of sampled tissues by 4 days post injection (dpi). However, WNV was not detected in tissues of sacrificed birds at 14 dpi, shortly after the development of detectable anti-WNV antibodies in the majority of birds indicating successful viral clearance. We compared susceptibility between the two zebra finch subspecies AZF and Timor zebra finch (TZF) T. g. guttata. Compared to AZF, WNV RNA was detected in a larger proportion of challenged TZF and molecular detection of virus in the serum of TZF was significantly higher than in AZF. Given the observed moderate host competence and disease susceptibility, we suggest that zebra finches are appropriate as models for the study of WNV and although underutilized in this respect, may be ideal models for the study of the many diseases carried and transmitted by songbirds.

  5. Plastic Responses of a Sessile Prey to Multiple Predators: A Field and Experimental Study

    PubMed Central

    Hirsch, Philipp Emanuel; Cayon, David; Svanbäck, Richard

    2014-01-01

    Background Theory predicts that prey facing a combination of predators with different feeding modes have two options: to express a response against the feeding mode of the most dangerous predator, or to express an intermediate response. Intermediate phenotypes protect equally well against several feeding modes, rather than providing specific protection against a single predator. Anti-predator traits that protect against a common feeding mode displayed by all predators should be expressed regardless of predator combination, as there is no need for trade-offs. Principal Findings We studied phenotypic anti-predator responses of zebra mussels to predation threat from a handling-time-limited (crayfish) and a gape-size-limited (roach) predator. Both predators dislodge mussels from the substrate but diverge in their further feeding modes. Mussels increased expression of a non-specific defense trait (attachment strength) against all combinations of predators relative to a control. In response to roach alone, mussels showed a tendency to develop a weaker and more elongated shell. In response to crayfish, mussels developed a harder and rounder shell. When exposed to either a combination of predators or no predator, mussels developed an intermediate phenotype. Mussel growth rate was positively correlated with an elongated weaker shell and negatively correlated with a round strong shell, indicating a trade-off between anti-predator responses. Field observations of prey phenotypes revealed the presence of both anti-predator phenotypes and the trade-off with growth, but intra-specific population density and bottom substrate had a greater influence than predator density. Conclusions Our results show that two different predators can exert both functionally equivalent and inverse selection pressures on a single prey. Our field study suggests that abiotic factors and prey population density should be considered when attempting to explain phenotypic diversity in the wild. PMID

  6. Host Fish Identification and Early Life Thermal Requirements for the Federal Endangered Winged Mapleleaf Mussel

    USGS Publications Warehouse

    Steingraeber, Mark; Newton, Teresa J.

    2005-01-01

    The winged mapleleaf mussel (Quadrula fragosa, WML) is a Federal endangered species historically inhabiting at least 34 river systems in 12 Midwestern states. Only four populations are currently known to exist, including one confirmed reproducing population in the St. Croix National Scenic Riverway (NSR) bordering Minnesota and Wisconsin. Recovery efforts are limited by a lack of life history information, particularly which species of fish serve as host to the mussel's parasitic larvae (glochidia). Since 1997, biologists at the University of Minnesota have tried to identify host fish for the WML. Department of the Interior colleagues working in western Wisconsin at the U.S. Fish and Wildlife Service's La Crosse Fishery Resources Office and Genoa National Fish Hatchery, the National Park Service's St. Croix NSR, and the U.S. Geological Survey's Upper Midwest Environmental Sciences Center (UMESC) in La Crosse joined the team in 2001 to expand and accelerate the laboratory host fish identification program by making use of the well-equipped aquatic research facilities at UMESC. We report on several WML early life history investigations conducted at UMESC since autumn 2003 to identify suitable host fish species and evaluate thermal requisites for the development of glochidia into free-living juvenile mussels.

  7. Magnetic resonance imaging of live freshwater mussels (Unionidae)

    USGS Publications Warehouse

    Michael, Holliman F.; Davis, Denise; Bogan, Arthur E.; Kwak, Thomas J.; Cope, W. Gregory; Levine, Jay F.

    2008-01-01

    We examined the soft tissues of live freshwater mussels, Eastern elliptio Elliptio complanata, via magnetic resonance imaging (MRI), acquiring data with a widely available human whole-body MRI system. Anatomical features depicted in the profile images included the foot, stomach, intestine, anterior and posterior adductor muscles, and pericardial cavity. Noteworthy observations on soft tissue morphology included a concentration of lipids at the most posterior aspect of the foot, the presence of hemolymph-filled fissures in the posterior adductor muscle, the presence of a relatively large hemolymph-filled sinus adjacent to the posterior adductor muscle (at the ventral-anterior aspect), and segmentation of the intestine (a diagnostic description not reported previously in Unionidae). Relatively little is known about the basic biology and ecological physiology of freshwater mussels. Traditional approaches for studying anatomy and tissue processes, and for measuring sub-lethal physiological stress, are destructive or invasive. Our study, the first to evaluate freshwater mussel soft tissues by MRI, clarifies the body plan of unionid mussels and demonstrates the efficacy of this technology for in vivoevaluation of the structure, function, and integrity of mussel soft tissues.

  8. Evaluation of the mussel fishery in Wheeler Reservoir, Tennessee River

    USGS Publications Warehouse

    Bowen, Zack H.; Malvestuto, S. P.; Davies, W. D.; Crance, J. H.

    1994-01-01

    We evaluated the freshwater mussel fishery on Wheeler Reservoir, a 27,155-hectare mainstream impoundment of the Tennessee River in Alabama. During July 1991 through June 1992, we used a roving creel survey to conduct 285 interviews over 57 weekdays and 12 weekend days. Total harvest during the 12-month survey period was estimated to be 570 metric tons, and included 15 mussel species. The most frequently harvested species were the washboard Megalonaias nervosa. Ohio pigtoe Pleurobema cordatum, and butterfly Ellipsaria lineolata. Harvest peaked in June at 290,414 mussels. Among collection techniques, total estimated effort was highest for divers (71,160 musseler-hours). The total estimated value of the 12-month mussel harvest (in terms of money paid to harvesters) from Wheeler Reservoir was US$2,119,921.

  9. Facile preparation of mussel-inspired polyurethane hydrogel and its rapid curing behavior.

    PubMed

    Sun, Peiyu; Wang, Jing; Yao, Xiong; Peng, Ying; Tu, Xiaoxiong; Du, Pengfei; Zheng, Zhen; Wang, Xinling

    2014-08-13

    A facile method was found to incorporate a mussel-inspired adhesive moiety into synthetic polymers, and mussel mimetic polyurethanes were developed as adhesive hydrogels. In these polymers, a urethane backbone was substituted for the polyamide chain of mussel adhesive proteins, and dopamine was appended to mimic the adhesive moiety of adhesive proteins. A series of mussel mimetic polyurethanes were created through a step-growth polymerization based on hexamethylene diisocyanate as a hard segment, PEG having different molecular weights as a soft segment, and lysine-dopamine as a chain extender. Upon a treatment with Fe(3+), the aqueous mussel mimetic polyurethane solutions can be triggered by pH adjustment to form adhesive hydrogels instantaneously; these materials can be used as injectable adhesive hydrogels. Upon a treatment with NaIO4, the mussel mimetic polyurethane solutions can be cured in a controllable period of time. The successful combination of the unique mussel-inspired adhesive moiety with a tunable polyurethane structure can result in a new kind of mussel-inspired adhesive polymers.

  10. Colour preferences in nest-building zebra finches.

    PubMed

    Muth, Felicity; Steele, Matthew; Healy, Susan D

    2013-10-01

    Some bird species are selective in the materials they choose for nest building, preferring, for example, materials of one colour to others. However, in many cases the cause of these preferences is not clear. One of those species is the zebra finch, which exhibits strong preferences for particular colours of nest material. In an attempt to determine why these birds strongly prefer one colour of material over another, we compared the preferences of paired male zebra finches for nest material colour with their preferences for food of the same colours. We found that birds did indeed prefer particular colours of nest material (in most cases blue) but that they did not generally prefer food of one colour over the other colours. It appears, then, that a preference for one colour or another of nest material is specific to the nest-building context. This article is part of a Special Issue entitled: insert SI title. Copyright © 2013 Elsevier B.V. All rights reserved.

  11. California mussels (Mytilus californianus) as sentinels for marine contamination with Sarcocystis neurona.

    PubMed

    Michaels, Lauren; Rejmanek, Daniel; Aguilar, Beatriz; Conrad, Patricia; Shapiro, Karen

    2016-05-01

    Sarcocystis neurona is a terrestrial parasite that can cause fatal encephalitis in the endangered Southern sea otter (Enhydra lutris nereis). To date, neither risk factors associated with marine contamination nor the route of S. neurona infection to marine mammals has been described. This study evaluated coastal S. neurona contamination using California mussels (Mytilus californianus) as sentinels for pathogen pollution. A field investigation was designed to test the hypotheses that (1) mussels can serve as sentinels for S. neurona contamination, and (2) S. neurona contamination in mussels would be highest during the rainy season and in mussels collected near freshwater. Initial validation of molecular assays through sporocyst spiking experiments revealed the ITS-1500 assay to be most sensitive for detection of S. neurona, consistently yielding parasite amplification at concentrations ⩾5 sporocysts/1 mL mussel haemolymph. Assays were then applied on 959 wild-caught mussels, with detection of S. neurona confirmed using sequence analysis in three mussels. Validated molecular assays for S. neurona detection in mussels provide a novel toolset for investigating marine contamination with this parasite, while confirmation of S. neurona in wild mussels suggests that uptake by invertebrates may serve as a route of transmission to susceptible marine animals.

  12. Evaluation of single and two-stage adaptive sampling designs for estimation of density and abundance of freshwater mussels in a large river

    USGS Publications Warehouse

    Smith, D.R.; Rogala, J.T.; Gray, B.R.; Zigler, S.J.; Newton, T.J.

    2011-01-01

    Reliable estimates of abundance are needed to assess consequences of proposed habitat restoration and enhancement projects on freshwater mussels in the Upper Mississippi River (UMR). Although there is general guidance on sampling techniques for population assessment of freshwater mussels, the actual performance of sampling designs can depend critically on the population density and spatial distribution at the project site. To evaluate various sampling designs, we simulated sampling of populations, which varied in density and degree of spatial clustering. Because of logistics and costs of large river sampling and spatial clustering of freshwater mussels, we focused on adaptive and non-adaptive versions of single and two-stage sampling. The candidate designs performed similarly in terms of precision (CV) and probability of species detection for fixed sample size. Both CV and species detection were determined largely by density, spatial distribution and sample size. However, designs did differ in the rate that occupied quadrats were encountered. Occupied units had a higher probability of selection using adaptive designs than conventional designs. We used two measures of cost: sample size (i.e. number of quadrats) and distance travelled between the quadrats. Adaptive and two-stage designs tended to reduce distance between sampling units, and thus performed better when distance travelled was considered. Based on the comparisons, we provide general recommendations on the sampling designs for the freshwater mussels in the UMR, and presumably other large rivers.

  13. Zebra: a web server for bioinformatic analysis of diverse protein families.

    PubMed

    Suplatov, Dmitry; Kirilin, Evgeny; Takhaveev, Vakil; Svedas, Vytas

    2014-01-01

    During evolution of proteins from a common ancestor, one functional property can be preserved while others can vary leading to functional diversity. A systematic study of the corresponding adaptive mutations provides a key to one of the most challenging problems of modern structural biology - understanding the impact of amino acid substitutions on protein function. The subfamily-specific positions (SSPs) are conserved within functional subfamilies but are different between them and, therefore, seem to be responsible for functional diversity in protein superfamilies. Consequently, a corresponding method to perform the bioinformatic analysis of sequence and structural data has to be implemented in the common laboratory practice to study the structure-function relationship in proteins and develop novel protein engineering strategies. This paper describes Zebra web server - a powerful remote platform that implements a novel bioinformatic analysis algorithm to study diverse protein families. It is the first application that provides specificity determinants at different levels of functional classification, therefore addressing complex functional diversity of large superfamilies. Statistical analysis is implemented to automatically select a set of highly significant SSPs to be used as hotspots for directed evolution or rational design experiments and analyzed studying the structure-function relationship. Zebra results are provided in two ways - (1) as a single all-in-one parsable text file and (2) as PyMol sessions with structural representation of SSPs. Zebra web server is available at http://biokinet.belozersky.msu.ru/zebra .

  14. NMR Profiling of Metabolites in Larval and Juvenile Blue Mussels (Mytilus edulis) under Ambient and Low Salinity Conditions

    PubMed Central

    Bishop, Karl D.; Rawson, Paul D.

    2017-01-01

    Blue mussels (Mytilus edulis) are ecologically and economically important marine invertebrates whose populations are at risk from climate change-associated variation in their environment, such as decreased coastal salinity. Blue mussels are osmoconfomers and use components of the metabolome (free amino acids) to help maintain osmotic balance and cellular function during low salinity exposure. However, little is known about the capacity of blue mussels during the planktonic larval stages to regulate metabolites during osmotic stress. Metabolite studies in species such as blue mussels can help improve our understanding of the species’ physiology, as well as their capacity to respond to environmental stress. We used 1D 1H nuclear magnetic resonance (NMR) and 2D total correlation spectroscopy (TOCSY) experiments to describe baseline metabolite pools in larval (veliger and pediveliger stages) and juvenile blue mussels (gill, mantle, and adductor tissues) under ambient conditions and to quantify changes in the abundance of common osmolytes in these stages during low salinity exposure. We found evidence for stage- and tissue-specific differences in the baseline metabolic profiles of blue mussels, which reflect variation in the function and morphology of each larval stage or tissue type of juveniles. These differences impacted the utilization of osmolytes during low salinity exposure, likely stemming from innate physiological variation. This study highlights the importance of foundational metabolomic studies that include multiple tissue types and developmental stages to adequately evaluate organismal responses to stress and better place these findings in a broader physiological context. PMID:28684716

  15. Seasonal variations of arsenic in mussels Mytilus galloprovincialis

    NASA Astrophysics Data System (ADS)

    Klarić, Sanja; Pavičić-Hamer, Dijana; Lucu, Čedomil

    2004-10-01

    Total arsenic concentration in the edible part of mussels Mytilus galloprovincialis was evaluated seasonally in the coastal area of Rijeka Bay (North Adriatic Sea, Croatia). Sampling stations were located close to the City of Bakar with no industrial facilities (site 1), in the vicinity of the oil refinery and oil thermoelectric power plant (Urinj, site 2), and 4 miles away from the Plomin coal thermoelectric power plant (Brseč village, site 3). Additionally, the concentration of arsenic in the tail muscle of the lobster Nephrops norvegicus, collected in Rijeka Bay, was studied. During winter at sites 2 and 3, the total arsenic in the edible part of the mussels was 16.4 mg As/kg FW (FW=fresh weight) and 4.38 mg As/kg FW, respectively, and increased during springtime at site 2 (6.5 mg As/kg FW) compared to the rest of the year, when individual total arsenic concentration at all sites ranged from 1.7 to 3.7 mg As/kg FW. In the winter (sites 2 and 3) and springtime (site 2) there was no correlation between the length of the mussel shell and the arsenic concentration in the edible part of the mussels. In the other seasons, at sites 1, 2 and 3, there was a correlation between arsenic in the edible part of mussels and shell length in most cases (correlation coefficients r varied from 0.64 to 0.85; P <0.05 to P <0.01). Correlation between shell length (in the narrow range of shell lengths from 3.4 to 5.0 cm) and arsenic in the edible part of the mussels shows linearity with a high regression coefficient (r =0.914; P <0.001). The increase of arsenic in the mussels during winter and spring was suggested at least partially as a result of a low nutritional status, i.e. reduced weight of the mussels' edible part during winter. In addition, a linear relationship was found between body length and arsenic concentration in the tail muscle (mean 17.11±4.48 mg As/kg FW) of the Norway lobster.

  16. Heavy metal contamination along the China coastline: A comprehensive study using Artificial Mussels and native mussels.

    PubMed

    Degger, Natalie; Chiu, Jill M Y; Po, Beverly H K; Tse, Anna C K; Zheng, Gene J; Zhao, Dong-Mei; Xu, Di; Cheng, Yu-Shan; Wang, Xin-Hong; Liu, Wen-Hua; Lau, T C; Wu, Rudolf S S

    2016-09-15

    A comprehensive study was carried out to assess metal contamination in five cities spanning from temperate to tropical environment along the coastal line of China with different hydrographical conditions. At each of the five cities, Artificial Mussels (AM) were deployed together with a native species of mussel at a control site and a polluted site. High levels of Cr, Cu and Hg were found in Qingdao, high level of Cd, Hg and Pb was found in Shanghai, and high level of Zn was found in Dalian. Furthermore, level of Cu contamination in all the five cities was consistently much higher than those reported in similar studies in other countries (e.g., Australia, Portugal, Scotland, Iceland, Korea, South Africa and Bangladesh). Levels of individual metal species in the AM showed a highly significant correlation with that in the native mussels (except for Zn in Mytilus edulis and Cd in Perna viridis), while no significant difference can be found between the regression relationships of metal in the AM and each of the two native mussel species. The results demonstrated that AM can provide a reliable time-integrated estimate of metal concentration in contrasting environments over large biogeographic areas and different hydrographic conditions, and overcome the shortcomings of monitoring metals in water, sediment and the use of biomonitors. Copyright © 2016 Elsevier Ltd. All rights reserved.

  17. Transcriptional Response of the Mussel Mytilus galloprovincialis (Lam.) following Exposure to Heat Stress and Copper

    PubMed Central

    Negri, Alessandro; Oliveri, Catherina; Sforzini, Susanna; Mignione, Flavio; Viarengo, Aldo; Banni, Mohamed

    2013-01-01

    Global warming is a major factor that may affect biological organization, especially in marine ecosystems and in coastal areas that are particularly subject to anthropogenic pollution. We evaluated the effects of simultaneous changes in temperature and copper concentrations on lysosomal membrane stability (N-acetyl-hexosaminidase activity) and malondialdehyde accumulation (MDA) in the gill of the blue mussel Mytilus galloprovincialis (Lam.). Temperature and copper exerted additive effects on lysosomal membrane stability, exacerbating the toxic effects of metal cations present in non-physiological concentrations. Mussel lysosomal membrane stability is known to be positively related to scope for growth, indicating possible effects of increasing temperature on mussel populations in metal-polluted areas. To clarify the molecular response to environmental stressors, we used a cDNA microarray with 1,673 sequences to measure the relative transcript abundances in the gills of mussels exposed to copper (40 µg/L) and a temperature gradient (16°C, 20°C, and 24°C). In animals exposed only to heat stress, hierarchical clustering of the microarray data revealed three main clusters, which were largely dominated by down-regulation of translation-related differentially expressed genes, drastic up-regulation of protein folding related genes, and genes involved in chitin metabolism. The response of mussels exposed to copper at 24°C was characterized by an opposite pattern of the genes involved in translation, most of which were up-regulated, as well as the down-regulation of genes encoding heat shock proteins and “microtubule-based movement” proteins. Our data provide novel information on the transcriptomic modulations in mussels facing temperature increases and high copper concentrations; these data highlight the risk of marine life exposed to toxic chemicals in the presence of temperature increases due to climate change. PMID:23825565

  18. Connectivity clues from short-term variability in settlement and geochemical tags of mytilid mussels

    NASA Astrophysics Data System (ADS)

    Fodrie, F. Joel; Becker, Bonnie J.; Levin, Lisa A.; Gruenthal, Kristen; McMillan, Pat A.

    2011-01-01

    The use of geochemical tags in calcified structures of fish and invertebrates is an exciting tool for investigating larval population connectivity. Tag evaluation over relatively short intervals (weeks) may detect environmental and ecological variability at a temporal scale highly relevant to larval transport and settlement. We collected newly settled mussels ( Mytilus californianus and M. galloprovincialis) weekly during winter/spring of 2002 along the coast of San Diego, CA, USA, at sites on the exposed coast (SIO) and in a protected coastal bay (HI), to investigate temporal patterns of geochemical tags in mussel shells. Analyses of post-settlement shell via LA-ICP-MS revealed statistically significant temporal variability for all elements we examined (Mg, Mn, Cu, Sr, Cd, Ba, Pb and U). Despite this, our ability to distinguish multielemental signatures between sites was largely conserved. Throughout our 13-week study, SIO and HI mussels could be chemically distinguished from one another in 78-87% of all cases. Settlement varied between 2 and 27 settlers gram-byssus -1 week -1 at SIO and HI, and both sites were characterized by 2-3 weeks with "high" settlement. Geochemical tags recorded in early larval shell of newly settled mussels differed between "high" and "low" settlement weeks at both sites (MANOVA), driven by Mg and Sr at SIO (p = 0.013) and Sr, Cd, Ba and Pb at HI (p < 0.001). These data imply that shifts in larval sources or transport corridors were responsible for observed settlement variation, rather than increased larval production. In particular, increased settlement at HI was observed concurrent with the appearance of geochemical tags (e.g., elevated Cd), suggesting that those larvae were retained in upwelled water near the mouth of the bay. Such shifts may reflect short-term changes in connectivity among sites due to altered transport corridors, and influence the demography of local populations.

  19. SPATIALLY AND SPECTRALLY RESOLVED OBSERVATIONS OF A ZEBRA PATTERN IN A SOLAR DECIMETRIC RADIO BURST

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Chen Bin; Bastian, T. S.; Gary, D. E.

    2011-07-20

    We present the first interferometric observation of a zebra-pattern radio burst with simultaneous high spectral ({approx}1 MHz) and high time (20 ms) resolution. The Frequency-Agile Solar Radiotelescope Subsystem Testbed (FST) and the Owens Valley Solar Array (OVSA) were used in parallel to observe the X1.5 flare on 2006 December 14. By using OVSA to calibrate the FST, the source position of the zebra pattern can be located on the solar disk. With the help of multi-wavelength observations and a nonlinear force-free field extrapolation, the zebra source is explored in relation to the magnetic field configuration. New constraints are placed onmore » the source size and position as a function of frequency and time. We conclude that the zebra burst is consistent with a double-plasma resonance model in which the radio emission occurs in resonance layers where the upper-hybrid frequency is harmonically related to the electron cyclotron frequency in a coronal magnetic loop.« less

  20. Gene duplication and fragmentation in the zebra finch major histocompatibility complex

    PubMed Central

    2010-01-01

    Background Due to its high polymorphism and importance for disease resistance, the major histocompatibility complex (MHC) has been an important focus of many vertebrate genome projects. Avian MHC organization is of particular interest because the chicken Gallus gallus, the avian species with the best characterized MHC, possesses a highly streamlined minimal essential MHC, which is linked to resistance against specific pathogens. It remains unclear the extent to which this organization describes the situation in other birds and whether it represents a derived or ancestral condition. The sequencing of the zebra finch Taeniopygia guttata genome, in combination with targeted bacterial artificial chromosome (BAC) sequencing, has allowed us to characterize an MHC from a highly divergent and diverse avian lineage, the passerines. Results The zebra finch MHC exhibits a complex structure and history involving gene duplication and fragmentation. The zebra finch MHC includes multiple Class I and Class II genes, some of which appear to be pseudogenes, and spans a much more extensive genomic region than the chicken MHC, as evidenced by the presence of MHC genes on each of seven BACs spanning 739 kb. Cytogenetic (FISH) evidence and the genome assembly itself place core MHC genes on as many as four chromosomes with TAP and Class I genes mapping to different chromosomes. MHC Class II regions are further characterized by high endogenous retroviral content. Lastly, we find strong evidence of selection acting on sites within passerine MHC Class I and Class II genes. Conclusion The zebra finch MHC differs markedly from that of the chicken, the only other bird species with a complete genome sequence. The apparent lack of synteny between TAP and the expressed MHC Class I locus is in fact reminiscent of a pattern seen in some mammalian lineages and may represent convergent evolution. Our analyses of the zebra finch MHC suggest a complex history involving chromosomal fission, gene

  1. Gene duplication and fragmentation in the zebra finch major histocompatibility complex.

    PubMed

    Balakrishnan, Christopher N; Ekblom, Robert; Völker, Martin; Westerdahl, Helena; Godinez, Ricardo; Kotkiewicz, Holly; Burt, David W; Graves, Tina; Griffin, Darren K; Warren, Wesley C; Edwards, Scott V

    2010-04-01

    Due to its high polymorphism and importance for disease resistance, the major histocompatibility complex (MHC) has been an important focus of many vertebrate genome projects. Avian MHC organization is of particular interest because the chicken Gallus gallus, the avian species with the best characterized MHC, possesses a highly streamlined minimal essential MHC, which is linked to resistance against specific pathogens. It remains unclear the extent to which this organization describes the situation in other birds and whether it represents a derived or ancestral condition. The sequencing of the zebra finch Taeniopygia guttata genome, in combination with targeted bacterial artificial chromosome (BAC) sequencing, has allowed us to characterize an MHC from a highly divergent and diverse avian lineage, the passerines. The zebra finch MHC exhibits a complex structure and history involving gene duplication and fragmentation. The zebra finch MHC includes multiple Class I and Class II genes, some of which appear to be pseudogenes, and spans a much more extensive genomic region than the chicken MHC, as evidenced by the presence of MHC genes on each of seven BACs spanning 739 kb. Cytogenetic (FISH) evidence and the genome assembly itself place core MHC genes on as many as four chromosomes with TAP and Class I genes mapping to different chromosomes. MHC Class II regions are further characterized by high endogenous retroviral content. Lastly, we find strong evidence of selection acting on sites within passerine MHC Class I and Class II genes. The zebra finch MHC differs markedly from that of the chicken, the only other bird species with a complete genome sequence. The apparent lack of synteny between TAP and the expressed MHC Class I locus is in fact reminiscent of a pattern seen in some mammalian lineages and may represent convergent evolution. Our analyses of the zebra finch MHC suggest a complex history involving chromosomal fission, gene duplication and translocation in the

  2. Conservation status of freshwater mussels in Europe: state of the art and future challenges.

    PubMed

    Lopes-Lima, Manuel; Sousa, Ronaldo; Geist, Juergen; Aldridge, David C; Araujo, Rafael; Bergengren, Jakob; Bespalaya, Yulia; Bódis, Erika; Burlakova, Lyubov; Van Damme, Dirk; Douda, Karel; Froufe, Elsa; Georgiev, Dilian; Gumpinger, Clemens; Karatayev, Alexander; Kebapçi, Ümit; Killeen, Ian; Lajtner, Jasna; Larsen, Bjørn M; Lauceri, Rosaria; Legakis, Anastasios; Lois, Sabela; Lundberg, Stefan; Moorkens, Evelyn; Motte, Gregory; Nagel, Karl-Otto; Ondina, Paz; Outeiro, Adolfo; Paunovic, Momir; Prié, Vincent; von Proschwitz, Ted; Riccardi, Nicoletta; Rudzīte, Mudīte; Rudzītis, Māris; Scheder, Christian; Seddon, Mary; Şereflişan, Hülya; Simić, Vladica; Sokolova, Svetlana; Stoeckl, Katharina; Taskinen, Jouni; Teixeira, Amílcar; Thielen, Frankie; Trichkova, Teodora; Varandas, Simone; Vicentini, Heinrich; Zajac, Katarzyna; Zajac, Tadeusz; Zogaris, Stamatis

    2017-02-01

    Freshwater mussels of the Order Unionida provide important ecosystem functions and services, yet many of their populations are in decline. We comprehensively review the status of the 16 currently recognized species in Europe, collating for the first time their life-history traits, distribution, conservation status, habitat preferences, and main threats in order to suggest future management actions. In northern, central, and eastern Europe, a relatively homogeneous species composition is found in most basins. In southern Europe, despite the lower species richness, spatially restricted species make these basins a high conservation priority. Information on freshwater mussels in Europe is unevenly distributed with considerable differences in data quality and quantity among countries and species. To make conservation more effective in the future, we suggest greater international cooperation using standardized protocols and methods to monitor and manage European freshwater mussel diversity. Such an approach will not only help conserve this vulnerable group but also, through the protection of these important organisms, will offer wider benefits to freshwater ecosystems. © 2016 Cambridge Philosophical Society.

  3. Control of predacious flatworms Macrostomum sp. in culturing juvenile freshwater mussels

    USGS Publications Warehouse

    Zimmerman, L.L.; Neves, R.J.; Smith, D.G.

    2003-01-01

    Flatworms of the genus Macrostomum are voracious predators on newly metamorphosed juvenile freshwater mussels (Unionidae), which require a fish host to transform mussel larvae into free-living juveniles. Toxicity tests were performed with formalin (paracide-F, 37% formaldehyde) to determine the appropriate levels of treatment for eradicating these flatworms from host fish tanks without adversely affecting the culture of juvenile mussels. Results indicate that a 1-h shock treatment of 250 mg/L formalin or a 3-d continuous exposure to 20 mg/L of formalin kills adult Macrostomum but not fish. Observations indicate that a single treatment is insufficient to kill Macrostomum eggs, so a second treatment after 3 d is necessary to kill newly hatched flatworms. Newly metamorphosed freshwater mussels exposed to similar shock and continuous treatments of formalin were also killed. Thus, all host fish introduced for the purpose of mussel production should be quarantined and treated prophylactically to avoid the infestation of mussel culture systems with predacious flatworms.

  4. Alternative mechanisms alter the emergent properties of self-organization in mussel beds

    PubMed Central

    Liu, Quan-Xing; Weerman, Ellen J.; Herman, Peter M. J.; Olff, Han; van de Koppel, Johan

    2012-01-01

    Theoretical models predict that spatial self-organization can have important, unexpected implications by affecting the functioning of ecosystems in terms of resilience and productivity. Whether and how these emergent effects depend on specific formulations of the underlying mechanisms are questions that are often ignored. Here, we compare two alternative models of regular spatial pattern formation in mussel beds that have different mechanistic descriptions of the facilitative interactions between mussels. The first mechanism involves a reduced mussel loss rate at high density owing to mutual protection between the mussels, which is the basis of prior studies on the pattern formation in mussels. The second mechanism assumes, based on novel experimental evidence, that mussels feed more efficiently on top of mussel-generated hummocks. Model simulations point out that the second mechanism produces very similar types of spatial patterns in mussel beds. Yet the mechanisms predict a strikingly contrasting effect of these spatial patterns on ecosystem functioning, in terms of productivity and resilience. In the first model, where high mussel densities reduce mussel loss rates, patterns are predicted to strongly increase productivity and decrease the recovery time of the bed following a disturbance. When pattern formation is generated by increased feeding efficiency on hummocks, only minor emergent effects of pattern formation on ecosystem functioning are predicted. Our results provide a warning against predictions of the implications and emergent properties of spatial self-organization, when the mechanisms that underlie self-organization are incompletely understood and not based on the experimental study. PMID:22418256

  5. Proximate and fatty acid composition of zebra (Equus quagga burchellii) muscle and subcutaneous fat.

    PubMed

    Hoffman, Louwrens C; Geldenhuys, Greta; Cawthorn, Donna-Mareè

    2016-08-01

    The meat from African game species is healthy, naturally produced and increasingly popular with consumers. Among these species, zebra (Equus quagga burchellii) are growing in number in South Africa, with the meat from surplus animals holding potential to contribute to food security and economic stability. Despite being consumed locally and globally, little information exists on the composition of zebra meat. This study aimed to determine the proximate composition of zebra meat as well as the fatty acid composition of the intramuscular (IMF) and subcutaneous (SCF) fat. Zebra longissimus lumborum muscle was shown to have a high mean protein content (22.29 g per 100 g) and low mean fat content (1.47 g per 100 g). High proportions of polyunsaturated fatty acids (PUFAs) were found in the IMF (41.15%) and SCF (37.71%), mainly comprising α-linolenic (C18:3n-3) and linoleic (C18:2n-6) acids. Furthermore, the IMF and SCF had favourable PUFA/saturated fatty acid ratios (>0.4) and omega-6/omega-3 ratios (<4), indicating that both components are healthy lipid food sources. This study has shed new light on the nutritional value of zebra meat, which will not only be important for food product labelling, nutritional education and incorporation into food composition databases, but will also be indispensable for marketing and export purposes. © 2016 Society of Chemical Industry. © 2016 Society of Chemical Industry.

  6. Habitat degradation correlates with tolerance to climate-change related stressors in the green mussel Perna viridis from West Java, Indonesia.

    PubMed

    Wendling, Carolin Charlotte; Huhn, Mareike; Ayu, Nurina; Bachtiar, Ramadian; von Juterzenka, Karen; Lenz, Mark

    2013-06-15

    It is unclear whether habitat degradation correlates with tolerance of marine invertebrates to abiotic stress. We therefore tested whether resistance to climate change-related stressors differs between populations of the green mussel Perna viridis from a heavily impacted and a mostly pristine site in West Java, Indonesia. In laboratory experiments, we compared their oxygen consumption and mortality under lowered salinity (-13 and -18 units, both responses), hypoxia (0.5 mg/l, mortality only) and thermal stress (+7 °C, mortality only). Mussels from the eutrophied and polluted Jakarta Bay showed a significantly smaller deviation from their normal oxygen consumption and higher survival rates when stressed than their conspecifics from the unaffected Lada Bay. This shows that human induced habitat degradation correlates with mussel tolerance to environmental stress. We discuss possible mechanisms - e.g. the selection of tolerant genotypes or habitat-specific differences in the nutritional status of the mussels - that could explain our observation. Copyright © 2013 Elsevier Ltd. All rights reserved.

  7. Geographical structure of endosymbiotic bacteria hosted by Bathymodiolus mussels at eastern Pacific hydrothermal vents.

    PubMed

    Ho, Phuong-Thao; Park, Eunji; Hong, Soon Gyu; Kim, Eun-Hye; Kim, Kangchon; Jang, Sook-Jin; Vrijenhoek, Robert C; Won, Yong-Jin

    2017-05-30

    Chemolithoautotrophic primary production sustains dense invertebrate communities at deep-sea hydrothermal vents and hydrocarbon seeps. Symbiotic bacteria that oxidize dissolved sulfur, methane, and hydrogen gases nourish bathymodiolin mussels that thrive in these environments worldwide. The mussel symbionts are newly acquired in each generation via infection by free-living forms. This study examined geographical subdivision of the thiotrophic endosymbionts hosted by Bathymodiolus mussels living along the eastern Pacific hydrothermal vents. High-throughput sequencing data of 16S ribosomal RNA encoding gene and fragments of six protein-coding genes of symbionts were examined in the samples collected from nine vent localities at the East Pacific Rise, Galápagos Rift, and Pacific-Antarctic Ridge. Both of the parapatric sister-species, B. thermophilus and B. antarcticus, hosted the same numerically dominant phylotype of thiotrophic Gammaproteobacteria. However, sequences from six protein-coding genes revealed highly divergent symbiont lineages living north and south of the Easter Microplate and hosted by these two Bathymodiolus mussel species. High heterogeneity of symbiont haplotypes among host individuals sampled from the same location suggested that stochasticity associated with initial infections was amplified as symbionts proliferated within the host individuals. The mussel species presently contact one another and hybridize along the Easter Microplate, but the northern and southern symbionts appear to be completely isolated. Vicariance associated with orogeny of the Easter Microplate region, 2.5-5.3 million years ago, may have initiated isolation of the symbiont and host populations. Estimates of synonymous substitution rates for the protein-coding bacterial genes examined in this study were 0.77-1.62%/nucleotide/million years. Our present study reports the most comprehensive population genetic analyses of the chemosynthetic endosymbiotic bacteria based on high

  8. Acute sensitivity of a broad range of freshwater mussels to chemicals with different modes of toxic action.

    PubMed

    Wang, Ning; Ivey, Christopher D; Ingersoll, Christopher G; Brumbaugh, William G; Alvarez, David; Hammer, Edward J; Bauer, Candice R; Augspurger, Tom; Raimondo, Sandy; Barnhart, M Christopher

    2017-03-01

    Freshwater mussels, one of the most imperiled groups of animals in the world, are generally underrepresented in toxicity databases used for the development of ambient water quality criteria and other environmental guidance values. Acute 96-h toxicity tests were conducted to evaluate the sensitivity of 5 species of juvenile mussels from 2 families and 4 tribes to 10 chemicals (ammonia, metals, major ions, and organic compounds) and to screen 10 additional chemicals (mainly organic compounds) with a commonly tested mussel species, fatmucket (Lampsilis siliquoidea). In the multi-species study, median effect concentrations (EC50s) among the 5 species differed by a factor of ≤2 for chloride, potassium, sulfate, and zinc; a factor of ≤5 for ammonia, chromium, copper, and nickel; and factors of 6 and 12 for metolachlor and alachlor, respectively, indicating that mussels representing different families or tribes had similar sensitivity to most of the tested chemicals, regardless of modes of action. There was a strong linear relationship between EC50s for fatmucket and the other 4 mussel species across the 10 chemicals (r 2  = 0.97, slope close to 1.0), indicating that fatmucket was similar to other mussel species; thus, this commonly tested species can be a good surrogate for protecting other mussels in acute exposures. The sensitivity of juvenile fatmucket among different populations or cultured from larvae of wild adults and captive-cultured adults was also similar in acute exposures to copper or chloride, indicating captive-cultured adult mussels can reliably be used to reproduce juveniles for toxicity testing. In compiled databases for all freshwater species, 1 or more mussel species were among the 4 most sensitive species for alachlor, ammonia, chloride, potassium, sulfate, copper, nickel, and zinc; therefore, the development of water quality criteria and other environmental guidance values for these chemicals should reflect the sensitivity of mussels. In

  9. Effect of sediment settling on controlling golden mussel invasion in water transfer project

    NASA Astrophysics Data System (ADS)

    Xu, Mengzhen; Wang, Zhaoyin; Bogen, Jim; Pan, Baozhu

    2013-04-01

    Inter-basin water transfer projects have been widely used to solve uneven distribution of water resources and water shortage in China. Along with the transferring of water resources, golden mussel (Limnoperna fortunei), the filter-collector macro-invertebrate species originating from southern China has also been inadvertently transferred to new aquatic environment, resulting in quick and uncontrolled spread of the species. The golden mussels are invasive by nature and endowed with a strong byssus for attaching onto their habitat, allowing them to easily invade natural and artificial aquatic systems, which was resulted in high-density golden mussel attachment that causes serious bio-fouling. Invasion and bio-fouling by golden mussels in water transfer systems has drawn attention widely because it has resulted in high resistance to water flow, corrosion of pipe walls and even clogging of tunnels, as well as causing water pollution and ecological imbalance in the regions that receive water infested with golden mussels. Field investigation was conducted along the East River, which is the main drinking water resource for Cantong province and Hongkong, China, to study the natural habitats of golden mussels. Surveys of water transfer tunnels which carry water from the East River to several big cities in Cantong province were done to study golden mussel invasion and attachment in tunnels. It is found that in the natural habitat, golden mussels mainly attach to bedrock and bank stones and solid surfaces facing upstream, while no golden mussels are attached on the surfaces facing downstream and suffering sediment deposition. In the water transfer tunnels, golden mussel attachment densities of 40,000 individuals/m2 mainly occurred on the portion of tunnel walls which face downwards and thus avoid sedimentation. An experiment was designed to study the effect of sediment settling on golden mussel attachment. The results showed that settling of fine sediment particles affects

  10. Are Horses Like Zebras, or Vice Versa? Children's Sensitivity to the Asymmetries of Directional Comparisons

    ERIC Educational Resources Information Center

    Chestnut, Eleanor K.; Markman, Ellen M.

    2016-01-01

    Adults exhibit strong preferences when framing symmetrical relations. Adults prefer, for example, "A zebra is like a horse" to "A horse is like a zebra," and "The bicycle is near the building" to "The building is near the bicycle." This is because directional syntax requires more typical or prominent items…

  11. Toxicity of sediments potentially contaminated by coal mining and natural gas extraction to unionid mussels and commonly tested benthic invertebrates

    USGS Publications Warehouse

    Wang, Ning; Ingersoll, Christopher G.; Kunz, James L.; Brumbaugh, William G.; Kane, Cindy M.; Evans, R. Brian; Alexander, Steven; Walker, Craig; Bakaletz, Steve

    2013-01-01

    consistent with the field observations of impacts on mussel populations; (2) total recoverable metals, PAHs, or major ions, or all three in sediments might have contributed to the sediment toxicity; (3) the mussels were more sensitive to the contaminants in sediments than the commonly tested amphipod and midge; and (4) a sediment toxicity benchmark of 1.0 based on PECs may not be protective of mussels.

  12. Biochemical composition of three species of unionid mussels after emersion

    USGS Publications Warehouse

    Greseth, Shari L.; Cope, W.G.; Rada, R.G.; Waller, D.L.; Bartsch, M.R.

    2003-01-01

    Freshwater mussels are emersed (exposed to air) during conservation activities such as surveys and relocations. Success of these activities depends upon the ability of mussels to survive emersion and to re-burrow in the substratum. We evaluated the acute sublethal effects of emersion on three species of unionid mussels [pocketbook, Lampsilis cardium (Rafinesque, 1820); pimpleback, Quadrula pustulosa pustulosa (I. Lea, 1831); spike, Elliptio dilatata (Rafinesque, 1820)] by measuring three biochemicals (carbohydrate, lipid, protein) indicative of biochemical function and energy storage. Mussels were acclimated in water at 25??C and exposed to five air temperatures (15, 20, 25, 35 and 45??C) for 15, 30 and 60 min. After emersion, mussels were returned to water at 25??C and observed for 14 days. Samples of mantle tissue were taken after the 14-day postexposure period and analysed for carbohydrate, lipid and protein. Three-way analysis of variance (ANOVA) did not reveal consistent trends in carbohydrate, lipid or protein concentrations due to sex of mussels, duration of emersion, air temperature or their interaction terms that indicated biological compensation to stress. Overall mean carbohydrate concentrations were greatest (range 447-615 mg/g dry wt) among the species, followed by protein (179-289 mg/g dry wt) and lipids (26.7-38.1 mg/g dry wt). These results have positive implications for conducting conservation activities, because emersion over the range of temperatures (15-35??C) and durations (15-60 min) examined did not appear acutely harmful to mussels.

  13. Same-sex partner preference in zebra finches: pairing flexibility and choice.

    PubMed

    Tomaszycki, Michelle L; Zatirka, Brendon P

    2014-11-01

    This study examined flexibility and choice in same-sex pair-bonding behavior in adult zebra finches (Taeniopygia guttata). Zebra finches form life-long monogamous relationships and extra pair behavior is very low, making them an ideal species in which to study same-sex pairing. We examined same-sex behaviors using both semi-naturalistic choice paradigms and skewed sex ratios. In the first experiment, we allowed zebra finches to pair in aviaries with equal sex ratios as part of multiple experiments. On average, 6.4% (N = 78) of unmanipulated pairs were same-sex: all but one was female-female. In a second experiment, we identified pairs from same-sex cages and selected 20 total same-sex pairs (10 of each sex). We then gave pairs a chance to court and pair with members of the opposite sex and observed their behavior for three days. Females did not retain their partner, but most paired with males. In contrast, some males did retain their partner. Similarly, females were more likely to engage in pairing behaviors with males than with their partners or other females whereas males were equally likely to engage in same-sex and opposite-sex pairing behaviors. These findings suggest that same-sex partnerships in zebra finches can be facultative, based on the sex ratio of the group in which they live, but can also be a choice, when opportunities to pair with opposite-sex individuals are possible. Furthermore, it is possible that females are more flexible in this choice of same-sex partnerships than are males.

  14. Past climate change drives current genetic structure of an endangered freshwater mussel species.

    PubMed

    Inoue, Kentaro; Lang, Brian K; Berg, David J

    2015-04-01

    Historical-to-recent climate change and anthropogenic disturbance affect species distributions and genetic structure. The Rio Grande watershed of the United States and Mexico encompasses ecosystems that are intensively exploited, resulting in substantial degradation of aquatic habitats. While significant anthropogenic disturbances in the Rio Grande are recent, inhospitable conditions for freshwater organisms likely existed prior to such disturbances. A combination of anthropogenic and past climate factors may contribute to current distributions of aquatic fauna in the Rio Grande basin. We used mitochondrial DNA and 18 microsatellite loci to infer evolutionary history and genetic structure of an endangered freshwater mussel, Popenaias popeii, throughout the Rio Grande drainage. We estimated spatial connectivity and gene flow across extant populations of P. popeii and used ecological niche models (ENMs) and approximate Bayesian computation (ABC) to infer its evolutionary history during the Pleistocene. structure results recovered regional and local population clusters in the Rio Grande. ENMs predicted drastic reductions in suitable habitat during the last glacial maximum. ABC analyses suggested that regional population structure likely arose in this species during the mid-to-late Pleistocene and was followed by a late Pleistocene population bottleneck in New Mexico populations. The local population structure arose relatively recently, perhaps due to anthropogenic factors. Popenaias popeii, one of the few freshwater mussel species native to the Rio Grande basin, is a case study for understanding how both geological and anthropogenic factors shape current population genetic structure. Conservation strategies for this species should account for the fragmented nature of contemporary populations. © 2015 John Wiley & Sons Ltd.

  15. ZEBRA battery meets USABC goals

    NASA Astrophysics Data System (ADS)

    Dustmann, Cord-H.

    In 1990, the California Air Resources Board has established a mandate to introduce electric vehicles in order to improve air quality in Los Angeles and other capitals. The United States Advanced Battery Consortium has been formed by the big car companies, Electric Power Research Institute (EPRI) and the Department of Energy in order to establish the requirements on EV-batteries and to support battery development. The ZEBRA battery system is a candidate to power future electric vehicles. Not only because its energy density is three-fold that of lead acid batteries (50% more than NiMH) but also because of all the other EV requirements such as power density, no maintenance, summer and winter operation, safety, failure tolerance and low cost potential are fulfilled. The electrode material is plain salt and nickel in combination with a ceramic electrolyte. The cell voltage is 2.58 V and the capacity of a standard cell is 32 Ah. Some hundred cells are connected in series and parallel to form a battery with about 300 V OCV. The battery system including battery controller, main circuit-breaker and cooling system is engineered for vehicle integration and ready to be mounted in a vehicle [J. Gaub, A. van Zyl, Mercedes-Benz Electric Vehicles with ZEBRA Batteries, EVS-14, Orlando, FL, Dec. 1997]. The background of these features are described.

  16. Transcriptional response to West Nile virus infection in the zebra finch (Taeniopygia guttata)

    USGS Publications Warehouse

    Newhouse, Daniel J.; Hofmeister, Erik K.; Balakrishnan, Christopher N.

    2017-01-01

    West Nile virus (WNV) is a widespread arbovirus that imposes a significant cost to both human and wildlife health. WNV exists in a bird-mosquito transmission cycle in which passerine birds act as the primary reservoir host. As a public health concern, the mammalian immune response to WNV has been studied in detail. Little, however, is known about the avian immune response to WNV. Avian taxa show variable susceptibility to WNV and what drives this variation is unknown. Thus, to study the immune response to WNV in birds, we experimentally infected captive zebra finches (Taeniopygia guttata). Zebra finches provide a useful model, as like many natural avian hosts they are moderately susceptible to WNV and thus provide sufficient viremia to infect mosquitoes. We performed RNAseq in spleen tissue during peak viremia to provide an overview of the transcriptional response. In general, we find strong parallels with the mammalian immune response to WNV, including upregulation of five genes in the Rig-I-like receptor signalling pathway, and offer insights into avian-specific responses. Together with complementary immunological assays, we provide a model of the avian immune response to WNV and set the stage for future comparative studies among variably susceptible populations and species.

  17. How effective is intermittent chlorination to control adult mussel fouling in cooling water systems?

    PubMed

    Rajagopal, Sanjeevi; Van der Velde, Gerard; Van der Gaag, Marinus; Jenner, Henk A

    2003-01-01

    Mussel control in cooling water systems is generally achieved by means of chlorination. Chlorine is applied continuously or intermittently, depending on cost and discharge criteria. In this paper, we examined whether mussels will be able to survive intermittent chlorination because of their ability to close their valves during periods of chlorination. Experiments were carried out using three common species of mussels: a freshwater mussel, Dreissena polymorpha, a brackish water mussel, Mytilopsis leucophaeata and a marine mussel, Mytilus edulis. The mussels were subjected to continuous or intermittent (4 h chlorination followed by 4 h no chlorination) chlorination at concentrations varying from 1 to 3 mg l(-1) and their responses (lethal and sublethal) were compared to those of control mussels. In addition, shell valve activity of mussels was monitored using a Mussel-monitor. Data clearly indicate that mussels shut their valves as soon as chlorine is detected in the environment and open only after chlorine dosing is stopped. However, under continuous chlorination mussels are constrained to keep the shell valves shut continuously. The mussels subjected to continuous chlorination at 1 mg l(-1) showed 100% mortality after 588 h (D. polymorpha), 966 h (Mytilus edulis) and 1104 h (Mytilopsis leucophaeata), while those subjected to intermittent chlorination at 1 mg l(-1) showed very little or no mortality during the same periods. Filtration rate, foot activity index and shell valve movement of D. polymorpha, Mytilopsis leucophaeata and Mytilus edulis decreased more than 90% at 1 mg l(-1) chlorine residual when compared to control. However, mussels subjected to intermittent chlorination showed a similar reduction (about 90%) in filtration rate, foot activity index and shell valve movement during chlorination and 3% during breaks in chlorination. The data indicate that intermittent chlorination between 1 and 3 mg l(-1) applied at 4 h on and 4 h off cycle is unlikely to

  18. Predator Diversity Effects in an Exotic Freshwater Food Web

    PubMed Central

    Naddafi, Rahmat; Rudstam, Lars G.

    2013-01-01

    Cascading trophic interactions are often defined as the indirect effects of a predator on primary producers through the effect of the predator on herbivores. These effects can be both direct through removal of herbivores [density-mediated indirect interactions (DMIIs)] or indirect through changes in the behavior of the herbivores [trait-mediated indirect interactions (TMIIs)]. How the relative importance of these two indirect interactions varies with predator diversity remains poorly understood. We tested the effect of predator diversity on both TMIIs and DMIIs on phytoplankton using two competitive invasive dreissenid mussel species (zebra mussel and quagga mussel) as the herbivores and combinations of one, two or all three species of the predators pumpkinseed sunfish, round goby, and rusty crayfish. Predators had either direct access to mussels and induced both TMII and DMII, or no direct access and induced only TMII through the presence of risk cues. In both sets of treatments, the predators induced a trophic cascade which resulted in more phytoplankton remaining with predators present than with only mussels present. The trophic cascade was weaker in three-predator and two-predator treatments than in one-predator treatments when predators had direct access to dreissenids (DMIIs and TMIIs). Crayfish had higher cascading effects on phytoplankton than both pumpkinseed and round goby. Increased predator diversity decreased the strength of DMIIs but had no effect on the strength of TMIIs. The strength of TMIIs was higher with zebra than quagga mussels. Our study suggests that inter-specific interference among predators in multi-species treatments weakens the consumptive cascading effects of predation on lower trophic levels whereas the importance of predator diversity on trait mediated effects depends on predator identity. PMID:23991126

  19. Switch from sexual to parthenogenetic reproduction in a zebra shark

    PubMed Central

    Dudgeon, Christine L.; Coulton, Laura; Bone, Ren; Ovenden, Jennifer R.; Thomas, Severine

    2017-01-01

    Parthenogenesis is a natural form of asexual reproduction in which embryos develop in the absence of fertilisation. Most commonly found in plants and invertebrate organisms, an increasing number of vertebrate species have recently been reported employing this reproductive strategy. Here we use DNA genotyping to report the first demonstration of an intra-individual switch from sexual to parthenogenetic reproduction in a shark species, the zebra shark Stegostoma fasciatum. A co-housed, sexually produced daughter zebra shark also commenced parthenogenetic reproduction at the onset of maturity without any prior mating. The demonstration of parthenogenesis in these two conspecific individuals with different sexual histories provides further support that elasmobranch fishes may flexibly adapt their reproductive strategy to environmental circumstances. PMID:28091617

  20. Switch from sexual to parthenogenetic reproduction in a zebra shark.

    PubMed

    Dudgeon, Christine L; Coulton, Laura; Bone, Ren; Ovenden, Jennifer R; Thomas, Severine

    2017-01-16

    Parthenogenesis is a natural form of asexual reproduction in which embryos develop in the absence of fertilisation. Most commonly found in plants and invertebrate organisms, an increasing number of vertebrate species have recently been reported employing this reproductive strategy. Here we use DNA genotyping to report the first demonstration of an intra-individual switch from sexual to parthenogenetic reproduction in a shark species, the zebra shark Stegostoma fasciatum. A co-housed, sexually produced daughter zebra shark also commenced parthenogenetic reproduction at the onset of maturity without any prior mating. The demonstration of parthenogenesis in these two conspecific individuals with different sexual histories provides further support that elasmobranch fishes may flexibly adapt their reproductive strategy to environmental circumstances.

  1. Zebra chip development during storage: cause for concern?

    USDA-ARS?s Scientific Manuscript database

    Zebra chip disease is associated with infections by ‘Candidatus Liberibacter solanacearum’ (Lso), a bacterium spread by the potato psyllid Bactericera cockerelli. A major concern of the potato industry is the likelihood that Lso could cause asymptomatic infections prior to placement of tubers in col...

  2. What makes a healthy environment for native freshwater mussels?

    USGS Publications Warehouse

    ,

    2000-01-01

    Freshwater mussels are sensitive to contamination of sediment that they inhabit and to the water that they filter, making the presence of live, adult mussels an excellent indicator of ecosystem health and stability. Freshwater mussels are relatively immobile, imbedded in the streambed with part of the shell sticking up into the water so that they can filter water to obtain oxygen and food. This lack of mobility makes them particularly vulnerable to water and sediment contamination, changes in sedimentation, or prolonged drought. Thus, ecosystem health and stability are critical for their reproduction and survival.

  3. Tributyltin Effects on Juvenile Mussel Growth.

    DTIC Science & Technology

    1987-12-01

    of tributyltin ( TBT ) in two site~sjecific, flow- through bioassays with unfiltered seawater. Mean TBT concentrations were 70, 80 and 200 ng/l in Test...lave studied the PETS was evaluated over a 7-month period in effects of tributyltin ( TBT ) on mussel (Mtilus San Diego Bay using TBT leachates. A more...ME38 Z0B38 DN888 -749 11. TITILE (hkcAd S@=tyCnifibibol Tributyltin Effects on Juvenile Mussel Growth 12. PERSONAL AUTHOR(S) M.H. Salazar, S.M. Salazar

  4. Biochemical composition of three species of unionid mussels after emersion

    USGS Publications Warehouse

    Greseth, Shari L.; Cope, W.G.; Rada, R.G.; Waller, D.L.; Bartsch, M.R.

    2003-01-01

    Freshwater mussels are emersed (exposed to air) during conservation activities such as surveys and relocations. Success of these activities depends upon the ability of mussels to survive emersion and to re-burrow in the substratum. We evaluated the acute sublethal effects of emersion on three species of unionid mussels [pocketbook, Lampsilis cardium (Rafinesque, 1820); pimpleback, Quadrula pustulosa pustulosa (I. Lea, 1831); spike, Elliptio dilatata (Rafinesque, 1820)] by measuring three biochemicals (carbohydrate, lipid, protein) indicative of biochemical function and energy storage. Mussels were acclimated in water at 25A?C and exposed to five air temperatures (15, 20, 25, 35 and 45A?C) for 15, 30 and 60 min. After emersion, mussels were returned to water at 25A?C and observed for 14 days. Samples of mantle tissue were taken after the 14-day postexposure period and analysed for carbohydrate, lipid and protein. Three-way analysis of variance (ANOVA) did not reveal consistent trends in carbohydrate, lipid or protein concentrations due to sex of mussels, duration of emersion, air temperature or their interaction terms that indicated biological compensation to stress. Overall mean carbohydrate concentrations were greatest (range 447a??615 mg/g dry wt) among the species, followed by protein (179a??289 mg/g dry wt) and lipids (26.7a??38.1 mg/g dry wt). These results have positive implications for conducting conservation activities, because emersion over the range of temperatures (15a??35A?C) and durations (15a??60 min) examined did not appear acutely harmful to mussels.

  5. Recruitment in a sea anemone population: juvenile substrate becomes adult prey.

    PubMed

    Sebens, K P

    1981-08-14

    Populations of the sea anemone Anthopleura xanthogrammica (Brandt) occur in tide pools and surge channels below intertidal mussel beds where they capture mussels dislodged by wave action and by sea star foraging. Dense concentrations of small juvenile anemones occur only within mussel beds and are probably the result of larval settlement or differential survival in that habitat. Areas experimentally cleared of anemones showed that recruitment was primarily by migrating juveniles and that the rate of immigration over a 2-year period was much higher in experimental removal areas near mussel beds than in those further away. Mussel beds thus function as an important juvenile habitat (refuge and nursery); juveniles later migrate downward and are then in a position to capture dislodged mussels and grow to adult size.

  6. Effects of handling and aerial exposure on the survival of unionid mussels

    USGS Publications Warehouse

    Waller, D.L.; Rach, J.J.; Cope, W.G.; Miller, G.A.

    1995-01-01

    We conducted a relocation study of unionid mussels in Navigation Pool 7 of the upper Mississippi River (river mile 713.2) to evaluate survival after handling and aerial exposure. Two separate studies were conducted to compare seasonal differences in mussel survival; the first was initiated in June and the second in October. Amblema plicata plicata (subfamily Ambleminae) and Obliquaria reflexa (subfamily Lampsilinae) were studied. Mussels were marked, held out of water for either 0, 1, 4, or 8 h, and then placed into a 3 x 3 m grid (divided into nine 1-m super(2) units). The mussels were re-examined after four-five months to measure mortality in the control and treatment groups. Mussels of both species had >90% survival after aerial exposure up to 4 h in both studies. However, survival (number recaptured live / number recaptured live and dead) of mussels showed a decreasing trend with duration of exposure in the first study, but not in the second study. The overall recovery of marked mussels (number recaptured/number marked) was 91% in the first study and 87% in the second study. However, only 37% of O. reflexa mussels in the 8-h treatment were recovered in the first study; the adjusted survival (number live recaptured/number marked) of this treatment group was significantly (p < 0.05) lower (35%) than all other treatments.

  7. Acetylcholinesterase inhibition in the threeridge mussel (Amblema plicata) by chlorpyrifos: implications for biomonitoring

    USGS Publications Warehouse

    Doran, W.J.; Cope, W.G.; Rada, R.G.; Sandheinrich, M.B.

    2001-01-01

    The effects of chlorpyrifos, an organophosphorus insecticide, were examined on the activity of the nervous system enzyme acetylcholinesterase (AChE) in the threeridge mussel Amblema plicata in a 24-day laboratory test. Thirty-six mussels in each of seven treatments (18 mussels per duplicate) were exposed to chlorpyrifos (0.1, 0.2, 0.3, 0.6, and 1.2 mg/L), a solvent (acetone), and a solvent-free (well water) control for 12, 24, or 96 h. The activity of AChE was measured in the anterior adductor muscle of eight mussels from each treatment after exposure. To assess potential latent effects, six mussels from each treatment were removed after 24 h of exposure and transferred to untreated water for a 21-day holding period; AChE activity was measured on three mussels from each treatment at 7 and 21 days of the holding period. The activity of AChE in chlorpyrifos-exposed mussels did not differ from controls after 12 or 24 h of exposure (t- test, P>0.05), but was significantly less than controls after 96 h (t- test, P=0.01). AChE activity did not vary among mussels at 24 h of exposure (i.e., Day 0 of holding period) and those at Day 7 and Day 21 of the holding period. Overall changes in AChE activity of mussels during the test were unrelated to individual chlorpyrifos concentrations and exposure times (repeated measure ANOVA; (P=0.06). A power analysis revealed that the sample size must be increased from 2 to 5 replicates (8 to 20 mussels per time interval and test concentration) to increase the probability of detecting significant differences in AChE activity. This calculated increase in sample size has potential implications for future biomonitoring studies with chlorpyrifos and unionid mussels.

  8. Ruinous resident: the hydroid Ectopleura crocea negatively affects suspended culture of the mussel Mytilus galloprovincialis.

    PubMed

    Fitridge, Isla; Keough, Michael J

    2013-01-01

    Hydroids are major biofouling organisms in global aquaculture. Colonies of the hydroid Ectopleura crocea have recently established in Australian commercial mussel leases culturing Mytilus galloprovincialis. This study examined the impacts of E. crocea on mussel culture at two stages of the production cycle: spatfall and grow-out. Hydroids most commonly fouled the body, edge and dorsal regions of the mussel shell and cause a reduction in the length (4%) and weight (23%) of juvenile mussels. They also consumed mussel larvae in the field and in the laboratory. Prey numbers of many taxa, including mussel larvae, were consistent in natural hydroid diets regardless of the temporal variation in prey availability, implying some selectivity in hydroid feeding. In the laboratory, E. crocea consumed settling plantigrade mussel larvae more readily than trochophore or veliger larvae. Fouling by E. crocea is detrimental to mussel condition, and may affect the availability of wild mussel larvae in the commercial culture of M. galloprovincialis.

  9. Biodiversity on the brink: an assessment of conservation strategies for North American freshwater mussels

    Treesearch

    Wendell R. Haag; James D. Williams

    2014-01-01

    The North America freshwater mussel fauna has suffered an inordinately high recent extinction rate, and the small size and isolation of many remaining populations portends a continued diminishment of this fauna. Causes of extinction and imperilment are varied but revolve around massive habitat loss, deterioration, and fragmentation. The National Strategy for the...

  10. Transcription-dependent induction of G1 phase during the zebra fish midblastula transition.

    PubMed

    Zamir, E; Kam, Z; Yarden, A

    1997-02-01

    The early development of the zebra fish (Danio rerio) embryo is characterized by a series of rapid and synchronous cell cycles with no detectable transcription. This period is followed by the midblastula transition (MBT), during which the cell cycle gradually lengthens, cell synchrony is lost, and zygotic transcription is initially detected. In this work, we examined the changes in the pattern of the cell cycle during MBT in zebra fish and whether these changes are dependent on the initiation of zygotic transcription. To characterize the pattern of the early zebra fish cell cycles, the embryonic DNA content was determined by flow cytometric analysis. We found that G1 phase is below detection levels during the first 10 cleavages and can be initially detected at the onset of MBT. Inhibition of zygotic transcription, by microinjection of actinomycin D, abolished the appearance of G1 phase at MBT. Premature activation of zygotic transcription, by microinjection of nonspecific DNA, induced G1 phase before the onset of MBT, while coinjection of actinomycin D and nonspecific DNA abolished this early appearance of G1 phase. We therefore suggest that during the early development of the zebra fish embryo, G1 phase appears at the onset of MBT and that the activation of transcription at MBT is essential and sufficient for the G1-phase induction.

  11. Genetic structure of the benthic amphipod Diporeia (Amphipoda: Pontoporeiidae) and its relationship to abundance in Lake Superior

    EPA Science Inventory

    The freshwater amphipod Diporeia is a crucial part of the food web in the Laurentian Great Lakes, but has faced serious declines correlated with the invasion of zebra mussels (Dreissena polymorpha), except in Lake Superior, which has seen an increase in Diporeia abundance. Specul...

  12. Equid herpesvirus 9 (EHV-9) isolates from zebras in Ontario, Canada, 1989 to 2007.

    PubMed

    Rebelo, Ana Rita; Carman, Susy; Shapiro, Jan; van Dreumel, Tony; Hazlett, Murray; Nagy, Éva

    2015-04-01

    The objective of this study was to identify and partially characterize 3 equid herpesviruses that were isolated postmortem from zebras in Ontario, Canada in 1989, 2002, and 2007. These 3 virus isolates were characterized by plaque morphology, restriction fragment length polymorphism (RFLP) of their genomic deoxyribonucleic acid (DNA), real-time polymerase chain reaction (PCR) assay, and sequence analyses of the full length of the glycoprotein G (gG) gene (ORF70) and a portion of the DNA polymerase gene (ORF30). The isolates were also compared to 3 reference strains of equid herpesvirus 1 (EHV-1). Using rabbit kidney cells, the plaques for the isolates from the zebras were found to be much larger in size than the EHV-1 reference strains. The RFLP patterns of the zebra viruses differed among each other and from those of the EHV-1 reference strains. Real-time PCR and sequence analysis of a portion of the DNA polymerase gene determined that the herpesvirus isolates from the zebras contained a G at nucleotide 2254 and a corresponding N at amino acid position 752, which suggested that they could be neuropathogenic EHV-1 strains. However, subsequent phylogenetic analysis of the gG gene suggested that they were EHV-9 and not EHV-1.

  13. Chronic toxicity of copper and ammonia to juvenile freshwater mussels (Unionidae)

    USGS Publications Warehouse

    Wang, N.; Ingersoll, C.G.; Greer, I.E.; Hardesty, D.K.; Ivey, C.D.; Kunz, J.L.; Brumbaugh, W.G.; Dwyer, F.J.; Roberts, A.D.; Augspurger, T.; Kane, C.M.; Neves, R.J.; Barnhart, M.C.

    2007-01-01

    The objectives of the present study were to develop methods for conducting chronic toxicity tests with juvenile mussels under flow-through conditions and to determine the chronic toxicity of copper and ammonia to juvenile mussels using these methods. In two feeding tests, two-month-old fatmucket (Lampsilis siliquoidea) and rainbow mussel (Villosa iris) were fed various live algae or nonviable algal mixture for 28 d. The algal mixture was the best food resulting in high survival (???90%) and growth. Multiple copper and ammonia toxicity tests were conducted for 28 d starting with two-month-old mussels. Six toxicity tests using the algal mixture were successfully completed with a control survival of 88 to 100%. Among copper tests with rainbow mussel, fatmucket, and oyster mussel (Epioblasma capsaeformis), chronic value ([ChV], geometric mean of the no-observed-effect concentration and the lowest-observed-effect concentration) ranged from 8.5 to 9.8 ??g Cu/L for survival and from 4.6 to 8.5 ??g Cu/L for growth. Among ammonia tests with rainbow mussel, fatmucket, and wavy-rayed lampmussel (L. fasciola), the ChV ranged from 0.37 to 1.2 mg total ammonia N/L for survival and from 0.37 to 0.67 mg N/L for growth. These ChVs were below the U.S. Environmental Protection Agency 1996 chronic water quality criterion (WQC) for copper (15 ??g/L; hardness 170 mg/L) and 1999 WQC for total ammonia (1.26 mg N/L; pH 8.2 and 20??C). Results indicate that toxicity tests with two-month-old mussels can be conducted for 28 d with >80% control survival; growth was frequently a more sensitive endpoint compared to survival; and the 1996 chronic WQC for copper and the 1999 chronic WQC for total ammonia might not be adequately protective of the mussel species tested. However, a recently revised 2007 chronic WQC for copper based on the biotic ligand model may be more protective in the water tested. ?? 2007 SETAC.

  14. Water and sediment temperatures at mussel beds in the upper Mississippi River basin

    USGS Publications Warehouse

    Newton, Teresa J.; Sauer, Jennifer; Karns, Byron

    2013-01-01

    Native freshwater mussels are in global decline and urgently need protection and conservation. Declines in the abundance and diversity of North American mussels have been attributed to human activities that cause pollution, waterquality degradation, and habitat destruction. Recent studies suggest that effects of climate change may also endanger native mussel assemblages, as many mussel species are living close to their upper thermal tolerances. Adult and juvenile mussels spend a large fraction of their lives burrowed into sediments of rivers and lakes. Our objective was to measure surface water and sediment temperatures at known mussel beds in the Upper Mississippi (UMR) and St. Croix (SCR) rivers to estimate the potential for sediments to serve as thermal refugia. Across four mussel beds in the UMR and SCR, surface waters were generally warmer than sediments in summer, and were cooler than sediments in winter. This suggests that sediments may act as a thermal buffer for mussels in these large rivers. Although the magnitude of this effect was usually <3.0°C, sediments were up to 7.5°C cooler at one site in May, suggesting site-specific variation in the ability of sediments to act as thermal buffers. Sediment temperatures in the UMR exceeded those shown to cause mortality in laboratory studies. These data suggest that elevated water temperatures resulting from global warming, thermal discharges, water extraction, and/or droughts have the potential to adversely affect native mussel assemblages.

  15. Migratory herds of wildebeests and zebras indirectly affect calf survival of giraffes.

    PubMed

    Lee, Derek E; Kissui, Bernard M; Kiwango, Yustina A; Bond, Monica L

    2016-12-01

    In long-distance migratory systems, local fluctuations in the predator-prey ratio can exhibit extreme variability within a single year depending upon the seasonal location of migratory species. Such systems offer an opportunity to empirically investigate cyclic population density effects on short-term food web interactions by taking advantage of the large seasonal shifts in migratory prey biomass.We utilized a large-mammal predator-prey savanna food web to evaluate support for hypotheses relating to the indirect effects of "apparent competition" and "apparent mutualism" from migratory ungulate herds on survival of resident megaherbivore calves, mediated by their shared predator. African lions ( Panthera leo ) are generalist predators whose primary, preferred prey are wildebeests ( Connochaetes taurinus ) and zebras ( Equus quagga ), while lion predation on secondary prey such as giraffes ( Giraffa camelopardalis ) may change according to the relative abundance of the primary prey species.We used demographic data from five subpopulations of giraffes in the Tarangire Ecosystem of Tanzania, East Africa, to test hypotheses relating to direct predation and indirect effects of large migratory herds on calf survival of a resident megaherbivore. We examined neonatal survival via apparent reproduction of 860 adult females, and calf survival of 449 giraffe calves, during three precipitation seasons over 3 years, seeking evidence of some effect on neonate and calf survival as a consequence of the movements of large herds of migratory ungulates.We found that local lion predation pressure (lion density divided by primary prey density) was significantly negatively correlated with giraffe neonatal and calf survival probabilities. This supports the apparent mutualism hypothesis that the presence of migratory ungulates reduces lion predation on giraffe calves.Natural predation had a significant effect on giraffe calf and neonate survival, and could significantly affect giraffe

  16. Botulism challenge studies of a modified atmosphere package for fresh mussels: inoculated pack studies.

    PubMed

    Newell, C R; Ma, Li; Doyle, Michael

    2012-06-01

    A series of botulism challenge studies were performed to determine the possibility of production of botulinum toxin in mussels (Mytilus edulis) held under a commercial high-oxygen (60 to 65% O(2)), modified atmosphere packaging (MAP) condition. Spore mixtures of six strains of nonproteolytic Clostridium botulinum were introduced into mussel MAP packages receiving different packaging buffers with or without the addition of lactic acid bacteria. Dye studies and package flipping trials were conducted to ensure internalization of spores by packed mussels. Inoculated mussel packages were stored at normal (4°C) and abusive (12°C) temperatures for 21 and 13 days, respectively, which were beyond the packaged mussels' intended shelf life. Microbiological and chemical analyses were conducted at predetermined intervals (a total of five sampling times at each temperature), including total aerobic plate counts, C. botulinum counts, lactic acid bacterial counts, package headspace gas composition, pH of packaging buffer and mussel meat, and botulinum toxin assays of packaging buffer and mussel meat. Results revealed that C. botulinum inoculated in fresh mussels packed under MAP packaging did not produce toxin, even at an abusive storage temperature and when held beyond their shelf life. No evidence was found that packaging buffers or gas composition influenced the lack of botulinum toxin production in packed mussels.

  17. Biotic interactions at hydrothermal vents: Recruitment inhibition by the mussel Bathymodiolus thermophilus

    NASA Astrophysics Data System (ADS)

    Lenihan, H. S.; Mills, S. W.; Mullineaux, L. S.; Peterson, C. H.; Fisher, C. R.; Micheli, F.

    2008-12-01

    The structure and dynamics of marine communities are regulated in part by variation in recruitment. As in other ecosystems, recruitment at deep-sea hydrothermal vents is controlled by the interplay of propagule supply and behavior, gradients in physical-chemical conditions, and biotic interactions during pre- and post-settlement periods. Recent research along the East Pacific Rise indicates that inhibition of recently settled larvae by mobile predators (mainly limpets) influences patterns of recruitment and subsequent community succession. We conducted a manipulative experiment at the same sites (˜2510 m water depth) to test whether high-density assemblages of the mussel Bathymodiolus thermophilus also inhibit recruitment. In a preliminary study, recruitment of vent invertebrates within the faunal zone dominated by B. thermophilus was strikingly different at two sites, East Wall and Worm Hole. East Wall had high densities of mussels but very low total recruitment. In contrast, Worm Hole had few mussels but high recruitment. Using the submersible Alvin, we transplanted a large number of mussels from East Wall to Worm Hole and quantified recruitment on basalt blocks placed in three treatments: (1) naturally high densities of mussels at East Wall; (2) naturally low densities of mussels at Worm Hole; and (3) high densities of transplanted mussels at Worm Hole. After 11 months, a total of 24 taxa had recruited to the basalt blocks. Recruitment was 44-60% lower in the transplanted high-density mussel patch at Worm Hole and the natural high-density patch at East Wall than within the natural low-density patch at Worm Hole. Biotic processes that may have caused the pattern of recruitment observed included predation of larvae via water filtration by mussels, larval avoidance of superior competitors, interference competition, and enhanced predation by species within the mussel-bed community. Our results indicate that biotic interactions affecting recruitment must be

  18. Induction of settlement in mussel (Perna canaliculus) larvae by vessel noise.

    PubMed

    Wilkens, S L; Stanley, J A; Jeffs, A G

    2012-01-01

    Underwater sound plays an important role in the settlement behaviour of many coastal organisms. Large steel-hulled vessels are known to be a major source of underwater sound in the marine environment. The possibility that underwater sound from vessels may promote biofouling of hulls through triggering natural larval settlement cues was investigated for the mussel, Perna canaliculus. The mussel larvae showed significantly faster settlement when exposed to the underwater noise produced by a 125-m long steel-hulled passenger and freight ferry. Median time to attachment on the substrata (ie settlement) was reduced by 22% and the time taken for all experimental larvae to settle was reduced by 40% relative to a silent control. There was no difference in the survival of the mussel larvae among the various noise treatments. The decrease in settlement time of the mussel larvae appeared to correlate with the intensity of the vessel sound, suggesting that underwater sound emanating from vessels may be an important factor in exacerbating hull fouling by mussels.

  19. The use of waste mussel shells for the adsorption of dyes and heavy metals

    NASA Astrophysics Data System (ADS)

    Papadimitriou, Chrysi A.; Krey, Grigorios; Stamatis, Nikolaos; Kallaniotis, Argyris

    2016-04-01

    Mussel culture is very important sector of the Greek agricultural economy. The majority of mussel culture activities take place in the area of Central Macedonia, Greece, 60% of total mussel production in Greece producing almost 12 tons of waste mussels shells on a daily basis. Currently there is no legislation concerning the disposal of mussel shells. In the present study the waste shells were used for the removal of dyes and heavy metals from aqueous solutions while powdered mussel shells were added in activated sludge processes for the removal of hexavalent chromium. Mussel shells were cleaned, dried and then crushed in order to form a powder. Powdered mussels shells were used in standard adsorption experiments for the removal of methylene blue and methyl red as well as for the removal of Cr (VI), Cd and Cu. Moreover the powdered mussel shells were added in laboratory scale activated sludge reactors treating synthetic wastewater with hexavalent chromium, in order investigate the effects in activated sludge processes and their potential attribution to the removal of hexavalent chromium. Adsorption experiments indicated almost 100% color removal, while adsorption was directly proportional to the amount of powdered mussel shells added in each case. The isotherms calculated for the case of methylene blue indicated similar adsorption capacity and properties to those of the commercially available activated carbon SAE 2, Norit. High removal efficiencies were observed for the metals, especially in the case of chromium and copper. The addition of powdered mussel shells in the activated sludge processes enhanced the removal of chromium and phosphorus, while enabled the formation of heavier activated sludge flocs and thus enhanced the settling properties of the activated sludge.

  20. Zebra textures in carbonate rocks: Fractures produced by the force of crystallization during mineral replacement

    NASA Astrophysics Data System (ADS)

    Wallace, Malcolm W.; Hood, Ashleigh v. S.

    2018-06-01

    Zebra textures are enigmatic banded fabrics that occur in many carbonate-hosted ore deposits, dolomite hydrocarbon reservoirs and carbonate successions globally. They consist of a variety of minerals and are characterised by parallel light and dark bands that occur at a millimetre- to centimetre-scale. Based on petrological evidence, there is general consensus that the dark bands formed by replacement of the carbonate host rock. Historically, more contention surrounds the origin of the light bands, but the dominant view is that these are mineral-filled cavities, which is supported by overwhelming textural evidence. Overall, the feature common to all versions of zebra textures is mineral replacement of the original carbonate host. We suggest that mineral replacement (and the force of crystallization) in association with open space generation is a viable mechanism for the development of zebra cavity systems. Dissolution and open space generation in either evaporites or carbonates adjacent to the site of replacement reactions is necessary to remove the confining pressure from the rock and to allow the development of fractures. The pressure of the growing replacement crystals within the carbonate pervasively splits the carbonate apart, producing thin strips of carbonate surrounded by open space. The fractures may then be subject to dissolution and are later filled by cements. Very regular stratabound zebra textures (as found in ore deposits like Cadjebut, Australia and San Vicente, Peru) may be related to stratabound dissolution (of evaporites or carbonates), whereas irregularly distributed zebra textures are more likely to be associated with irregular carbonate dissolution.

  1. Newly documented host fishes for the eastern elliptio mussel (Elliptio complanata)

    USGS Publications Warehouse

    Galbraith, Heather S.

    2013-01-01

    The eastern elliptio (Elliptio complanata) is a common, abundant and ecologically important freshwater mussel that occurs throughout the Atlantic Slope drainage in the United States and Canada. Previous research has shown E. complanata glochidia to be host fish generalists, parasitizing yellow perch (Perca flavescens), banded killifish (Fundulus diaphanus), banded sculpin (Cottus carolinae), and seven centrarchid species. Past laboratory studies have been conducted in the Midwest and glochidia sources typically included lakes the Great Lakes basin or were unreported. The objective of this study was to identify host fishes for E. complanata from streams in the Mid-Atlantic region. We used artificial laboratory infections to test host suitability of 38 fish and two amphibian species with E. complanata glochidia from the Chesapeake Bay drainage. Glochidia successfully metamorphosed into juvenile mussels on five fish species: American eel (Anguilla rostrata), brook trout (Salvelinus fontinalis), lake trout (S. namaycush), mottled sculpin (C. bairdii), and slimy sculpin (C. cognatus). American eel was the most effective host, yielding the highest overall metamorphosis success (percentage of attached glochidia that transformed into juvenile mussels;{greater than or equal to}0.90) and producing 13.2 juveniles per fish overall. No juvenile E. complanata metamorphosed on other fish species tested, including many previously identified host fishes reported in the literature. Reasons for discrepancies in published host fish could include geographic variation in host use across the species' range, differences in host use between lentic and lotic populations, or poorly resolved taxonomy within the genus Elliptio.

  2. Relationships between community structure of freshwater mussels and host fishes in a central Ohio watershed

    USDA-ARS?s Scientific Manuscript database

    The diversity of freshwater mussel communities has declined over the past several decades within watersheds in the Midwestern United States. Host fishes play an important role in the life cycle of freshwater mussels because they serve as hosts for parasitic mussel larvae to ensure successful mussel ...

  3. Role of ecological factors and reproductive strategies in structuring freshwater mussel communities

    Treesearch

    Wendell R. Haag; Melvin L. Warren

    1998-01-01

    Freshwater mussel community composition within two drainage basins in Alabama, U.S.A., was better explained by patterns of variability in the fish community and the type of strategy used by mussels for infecting host-fishes than by patterns of variability in microhabitat. Mussel species richness increased in a downstream direction, and large-stream sites were...

  4. Trematode Aspidogastrea found in the freshwater mussels in the Yangtze River basin.

    PubMed

    Zhan, Xiaodong; Li, Chaopin; Wu, Hua

    2017-03-30

    To investigate the prevalence of trematode Aspidogastrea in the freshwater mussels in the Yangtze River basin within Anhui province, China. We initially harvested the freshwater mussels living in the Yangtze River running through Anhui area, and labeled them with corresponding number. Then the samples were dissected for isolating the flukes, which were identified by conventional staining. Infection rate of trematode Aspidogastrea in freshwater mussels in the Yangtze River basin within the territory of Anhui province was 30.38% (103/339) in general, and a total of 912 flukes of Aspidogastrea were detected in the 103 mussels, with average infection rate of 8.85 for each mussel. Trematode Aspidogastrea is prevalent in the freshwater bivalves living in the Yangtze River basin running through Anhui area, and the treamatode was identified as Aspidogaster sp. belong to Aspidogaste under Aspidogastridae of Aspidogastrea.

  5. Changes in freshwater mussel communities linked to legacy pollution in the Lower Delaware River

    USGS Publications Warehouse

    Blakeslee, Carrie J.; Silldorff, Erik L.; Galbraith, Heather S.

    2018-01-01

    Freshwater mussels are among the most-imperiled organisms worldwide, although they provide a variety of important functions in the streams and rivers they inhabit. Among Atlantic-slope rivers, the Delaware River is known for its freshwater mussel diversity and biomass; however, limited data are available on the freshwater mussel fauna in the lower, non-tidal portion of the river. This section of the Delaware River has experienced decades of water-quality degradation from both industrial and municipal sources, primarily as a function of one of its major tributaries, the Lehigh River. We completed semi-quantitative snorkel surveys in 53.5 of the 121 km of the river to document mussel community composition and the continued impacts from pollution (particularly inputs from the Lehigh River) on mussel fauna. We detected changes in mussel catch per unit effort (CPUE) below the confluence of the Lehigh River, with significant declines in the dominant species Elliptio complanata (Eastern Elliptio) as we moved downstream from its confluence—CPUE dropped from 179 to 21 mussels/h. Patterns in mussel distribution around the Lehigh confluence matched chemical signatures of Lehigh water input. Specifically, Eastern Elliptio CPUE declined more quickly moving downstream on the Pennsylvania bank, where Lehigh River water input was more concentrated compared to the New Jersey bank. A definitive causal link remains to be established between the Lehigh River and the dramatic shifts in mussel community composition, warranting continued investigation as it relates to mussel conservation and restoration in the basin.

  6. Habitat used by juvenile lake sturgeon (Acipenser fulvescens) in the North Channel of the St. Clair River (Michigan, USA)

    USGS Publications Warehouse

    Boase, James C.; Manny, Bruce A.; Donald, Katherine A.L.; Kennedy, Gregory W.; Diana, James S.; Thomas, Michael V.; Chiotti, Justin A.

    2014-01-01

    Lake sturgeon (Acipenser fulvescens) occupy the St. Clair River, part of a channel connecting lakes Huron and Erie in the Laurentian Great Lakes. In the North Channel of the St. Clair River, juvenile lake sturgeon (3–7 years old and 582–793 mm in length) were studied to determine movement patterns and habitat usage. Fourteen juveniles were implanted with ultrasonic transmitters and tracked June–August of 2004, 2005 and 2006. Telemetry data, Geographic Information System software, side-scan sonar, video images of the river bottom, scuba diving, and benthic substrate samples were used to determine the extent and composition of habitats they occupied. Juvenile lake sturgeon habitat selection was strongly related to water depth. No fish were found in 700 mm in length selected sand and gravel areas mixed with zebra mussels and areas dominated by zebra mussels, while fish < 700 mm used these habitat types in proportion to their availability.

  7. Discrimination of Mediterranean mussel (Mytilus galloprovincialis) feces in deposited materials by fecal morphology.

    PubMed

    Akiyama, Yoshihiro B; Iseri, Erina; Kataoka, Tomoya; Tanaka, Makiko; Katsukoshi, Kiyonori; Moki, Hirotada; Naito, Ryoji; Hem, Ramrav; Okada, Tomonari

    2017-02-15

    In the present study, we determined the common morphological characteristics of the feces of Mytilus galloprovincialis to develop a method for visually discriminating the feces of this mussel in deposited materials. This method can be used to assess the effect of mussel feces on benthic environments. The accuracy of visual morphology-based discrimination of mussel feces in deposited materials was confirmed by DNA analysis. Eighty-nine percent of mussel feces shared five common morphological characteristics. Of the 372 animal species investigated, only four species shared all five of these characteristics. More than 96% of the samples were visually identified as M. galloprovincialis feces on the basis of morphology of the particles containing the appropriate mitochondrial DNA. These results suggest that mussel feces can be discriminated with high accuracy on the basis of their morphological characteristics. Thus, our method can be used to quantitatively assess the effect of mussel feces on local benthic environments. Copyright © 2016 Elsevier Ltd. All rights reserved.

  8. A comparative study of authigenic carbonates from mussel and tubeworm environments: Implications for discriminating the effects of tubeworms

    NASA Astrophysics Data System (ADS)

    Feng, Dong; Cordes, Erik E.; Roberts, Harry H.; Fisher, Charles R.

    2013-05-01

    The Gulf of Mexico hydrocarbon seeps are often populated by dense mussel beds and tubeworm aggregations, as well as exposed authigenic carbonate outcrops. Previous studies suggest the activity of mussels and tubeworms could influence the sediment geochemistry of their habitats, resulting in variations in the stable carbon isotopes of the associated carbonates. However, this conclusion was based on the analyses of samples from a single site. To better understand whether there are consistent differences in the geochemical environments of mussels and tubeworms, mineralogical and stable isotopic compositions of authigenic carbonates from mussel and tubeworm environments from four seep sites were analyzed. The studied sites span a depth range of 1200 m to 2800 m on the northern Gulf of Mexico continental slope. We found that carbonate samples from tubeworm environments were more prone to contain aragonite whereas carbonates from mussel environments were more likely to have calcite. This finding supports the hypothesis that vestimentiferans release sulfate across their roots into the pore waters of the surrounding sediments, a process that could generate a locally sulfate-enriched environment that favors the precipitation of aragonite instead of calcite. Moreover, the δ13C values of tubeworm carbonates are generally lighter than that of mussel carbonates from the same site, which is consistent with the fact that tubeworms are fueling extra subsurface methane oxidation through the release of sulfate into the sediment. Such a process, consequently, enriches the subsurface dissolved inorganic carbon pool with light carbon derived from the seeping hydrocarbons. Taken together, our data suggest that tubeworms could produce a carbon isotope shift that is sufficient to influence the sediment geochemistry of their immediate area, and that this impact is reflected in the associated authigenic carbonates.

  9. Scanning electron microscopy of Strongylus spp. in zebra.

    PubMed

    Els, H J; Malan, F S; Scialdo-Krecek, R C

    1983-12-01

    The external ultrastructure of the anterior and posterior extremities of the nematodes, Strongylus asini , Strongylus vulgaris, Strongylus equinus and Strongylus edentatus, was studied with scanning electron microscopy (SEM). Fresh specimens of S. asini were collected from the caecum, ventral colon and vena portae of Equus burchelli and Equus zebra hartmannae ; S. vulgaris from the caecum, colon and arteria ileocolica of E. burchelli ; S. equinus from the ventral colon of E. z. hartmannae and S. edentatus from the caecum and ventral colon of both zebras , during surveys of parasites in zebras in the Etosha Game Reserve, South West Africa/Namibia, and the Kruger National Park, Republic of South Africa. The worms were cleaned, fixed and mounted by standard methods and photographed in a JEOL JSM - 35C scanning electron microscope (SEM) operating at 12kV . The SEM showed the following differences: the tips of the external leaf-crowns varied and were fine and delicate in S. asini , coarse and broad in S. vulgaris and, in S. equinus and S. edentatus, closely adherent, separating into single elements for half their length. The excretory pores showed only slight variation, and the morphology of the copulatory bursae did not differ from those seen with light microscopy. The genital cones differed markedly: S. asini had a ventral triangular projection and laterally 2 finger-like projections: in S. vulgaris there were numerous bosses on the lateral and ventral aspects of the cone; in S. equinus 2 finger-like processes projected laterocaudally ; and in S. edentatus 2 pairs of papilla-like processes projected laterally on the ventral aspects, and a pair of rounded projections and a pair of hair-like structures adorned the dorsal aspects.(ABSTRACT TRUNCATED AT 250 WORDS)

  10. Sexual imprinting on continuous variation: do female zebra finches prefer or avoid unfamiliar sons of their foster parents?

    PubMed

    Schielzeth, H; Burger, C; Bolund, E; Forstmeier, W

    2008-09-01

    Sexual imprinting on discrete variation that serves the identification of species, morphs or sexes is well documented. By contrast, sexual imprinting on continuous variation leading to individual differences in mating preferences within a single species, morph and sex has been studied only once (in humans). We measured female preferences in a captive population of wild-type zebra finches. Individual cross-fostering ensured that all subjects grew up with unrelated foster parents and nest mates. Females from two cohorts (N = 113) were given a simultaneous choice between (two or four) unfamiliar males, one of which was a genetic son of their foster parents (SFP). We found no significant overall preference for the SFP (combined effect size d = 0.14 +/- 0.15). Additionally, we tested if foster parent traits could potentially explain between-female variation in preferences. However, neither the effectiveness of cooperation between the parents nor male contribution to parental care affected female preferences for the son of the foster father. We conclude that at least in zebra finches sexual imprinting is not a major source of between-individual variation in mating preferences.

  11. Staged Z-pinch Experiments on Cobra and Zebra

    NASA Astrophysics Data System (ADS)

    Wessel, Frank J.; Anderson, A.; Banasek, J. T.; Byvank, T.; Conti, F.; Darling, T. W.; Dutra, E.; Glebov, V.; Greenly, J.; Hammer, D. A.; Potter, W. M.; Rocco, S. V.; Ross, M. P.; Ruskov, E.; Valenzuela, J.; Beg, F.; Covington, A.; Narkis, J.; Rahman, H. U.

    2017-10-01

    A Staged Z-pinch (SZP), configured as a pre-magnetized, high-Z (Ar, or Kr) annular liner imploding onto a low-Z (H, or D) target, was tested on the Cornell University, Cobra Facility and the University of Nevada, Reno, Zebra Facility; each characterized similarly by a nominal 1-MA current and 100-ns risetime while possessing different diagnostic packages. XUV-fast imaging reveals that the SZP implosion dynamics is similar on both machines and that it is more stable with an axial (Bz) magnetic field, a target, or both, than without. On Zebra, where neutron production is possible, reproducible thermonuclear (DD) yields were recorded at levels in excess of 109/shot. Flux compression in the SZP is also expected to produce magnetic field intensities of the order of kilo-Tesla. Thus, the DD reaction produced tritions should also yield secondary DT neutrons. Indeed, secondaries are measured above the noise threshold at levels approaching 106/shot. Funded by the Advanced Research Projects Agency - Energy, under Grant Number DE-AR0000569.

  12. Zebra finch mates use their forebrain song system in unlearned call communication.

    PubMed

    Ter Maat, Andries; Trost, Lisa; Sagunsky, Hannes; Seltmann, Susanne; Gahr, Manfred

    2014-01-01

    Unlearned calls are produced by all birds whereas learned songs are only found in three avian taxa, most notably in songbirds. The neural basis for song learning and production is formed by interconnected song nuclei: the song control system. In addition to song, zebra finches produce large numbers of soft, unlearned calls, among which "stack" calls are uttered frequently. To determine unequivocally the calls produced by each member of a group, we mounted miniature wireless microphones on each zebra finch. We find that group living paired males and females communicate using bilateral stack calling. To investigate the role of the song control system in call-based male female communication, we recorded the electrical activity in a premotor nucleus of the song control system in freely behaving male birds. The unique combination of acoustic monitoring together with wireless brain recording of individual zebra finches in groups shows that the neuronal activity of the song system correlates with the production of unlearned stack calls. The results suggest that the song system evolved from a brain circuit controlling simple unlearned calls to a system capable of producing acoustically rich, learned vocalizations.

  13. Zebra Finch Mates Use Their Forebrain Song System in Unlearned Call Communication

    PubMed Central

    Ter Maat, Andries; Trost, Lisa; Sagunsky, Hannes; Seltmann, Susanne; Gahr, Manfred

    2014-01-01

    Unlearned calls are produced by all birds whereas learned songs are only found in three avian taxa, most notably in songbirds. The neural basis for song learning and production is formed by interconnected song nuclei: the song control system. In addition to song, zebra finches produce large numbers of soft, unlearned calls, among which “stack” calls are uttered frequently. To determine unequivocally the calls produced by each member of a group, we mounted miniature wireless microphones on each zebra finch. We find that group living paired males and females communicate using bilateral stack calling. To investigate the role of the song control system in call-based male female communication, we recorded the electrical activity in a premotor nucleus of the song control system in freely behaving male birds. The unique combination of acoustic monitoring together with wireless brain recording of individual zebra finches in groups shows that the neuronal activity of the song system correlates with the production of unlearned stack calls. The results suggest that the song system evolved from a brain circuit controlling simple unlearned calls to a system capable of producing acoustically rich, learned vocalizations. PMID:25313846

  14. Tolerance to stress differs between Asian green mussels Perna viridis from the impacted Jakarta Bay and from natural habitats along the coast of West Java.

    PubMed

    Huhn, Mareike; Hattich, Giannina S I; Zamani, Neviaty P; von Juterzenka, Karen; Lenz, Mark

    2016-09-30

    It is an open question whether adverse habitat conditions, characteristic for many anthropogenically impacted coastal habitats, can determine resistance to abiotic stress in populations of residing invertebrates. We tested experimentally for differences in stress tolerance between individuals of the Asian green mussel Perna viridis stemming from the heavily impacted Jakarta Bay and from two natural sites, Lada Bay and Pelabuhan Ratu, West Java. Mussel performance under hyposalinity and hypoxia was assessed in laboratory assays by measuring fitness-related response variables, e.g. body condition index, relative shell weight, byssus production, respiration rates and survival. We found stress-specific and population-specific differences in mussel resistance to adverse conditions: Individuals from the impacted Jakarta Bay performed better under hypoxia than their conspecifics from the natural sites, whereas the latter were more resistant to hyposalinity. We explain these differences by differential acclimation to environmental conditions in the respective habitats and by diverging degrees of food supply. Copyright © 2016 Elsevier Ltd. All rights reserved.

  15. Polonium-210 in marine mussels (bivalve molluscs) inhabiting the southern coast of India.

    PubMed

    Khan, M Feroz; Wesley, S Godwin; Rajan, M P

    2014-12-01

    The present study focused on the determination of the alpha-emitter, (210)Po, in two species of marine mussels (bivalve molluscs) commonly available in the southern coastal region of India. The brown mussel, Perna indica was collected from the west coast and the green mussel, Perna viridis from the east coast. The concentration of (210)Po was related to the allometry (length of shell, wet/dry weight of shell/soft tissue) of the mussels and significant results were found. The study period focused on three seasons namely, pre-monsoon, monsoon and post-monsoon for a 1-year period (2010-2011). The results revealed higher activity levels in smaller-sized mussels compared to larger ones. Marked variation in (210)Po activity concentration was noted in the whole-body soft tissues between seasons and sampling site (p < 0.05). The dose rate assessment for mussels was performed using the ERICA Assessment tool. The chronic exposure to mussels due to (210)Po was found to be lesser than the global benchmark dose rate of 10 μGy h(-1). The effective ingestion dose to adults who intake mussels was estimated to be in the range 5.1-34.9 μSv y(-1). The measurement contributes to the furthering of knowledge of (210)Po, since no data exist in this region. Copyright © 2014 Elsevier Ltd. All rights reserved.

  16. North American freshwater mussels: natural history, ecology, and conservation

    Treesearch

    Wendell R. Haag

    2012-01-01

    Interest in freshwater mussels is growing for two important reasons. First, freshwater mussels are among the most endangered organisms on Earth, and many species are already extinct or face imminent extinction. Their desperate conservation plight has gained intense interest from natural resource agencies, nongovernmental conservation organizations, academia, and...

  17. Batteries: An Advanced Na-FeCl2 ZEBRA Battery for Stationary Energy Storage Application

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Li, Guosheng; Lu, Xiaochuan; Kim, Jin Yong

    2015-06-17

    Sodium-metal chloride batteries, ZEBRA, are considered as one of the most important electrochemical devices for stationary energy storage applications because of its advantages of good cycle life, safety, and reliability. However, sodium-nickel chloride (Na-NiCl2) batteries, the most promising redox chemistry in ZEBRA batteries, still face great challenges for the practical application due to its inevitable feature of using Ni cathode (high materials cost). In this work, a novel intermediate-temperature sodium-iron chloride (Na-FeCl2) battery using a molten sodium anode and Fe cathode is proposed and demonstrated. The first use of unique sulfur-based additives in Fe cathode enables Na-FeCl2 batteries can bemore » assembled in the discharged state and operated at intermediate-temperature (<200°C). The results in this work demonstrate that intermediate-temperature Na-FeCl2 battery technology could be a propitious solution for ZEBRA battery technologies by replacing the traditional Na-NiCl2 chemistry.« less

  18. Prospects for Biocontrol of Vibrio parahaemolyticus Contamination in Blue Mussels (Mytilus edulus)—A Year-Long Study

    PubMed Central

    Onarinde, Bukola A.; Dixon, Ronald A.

    2018-01-01

    Vibrio parahaemolyticus is an environmental organism normally found in subtropical estuarine environments which can cause seafood-related human infections. Clinical disease is associated with diagnostic presence of tdh and/or trh virulence genes and identification of these genes in our preliminary isolates from retail shellfish prompted a year-long surveillance of isolates from a temperate estuary in the north of England. The microbial and environmental analysis of 117 samples of mussels, seawater or sediment showed the presence of V. parahaemolyticus from mussels (100%) at all time-points throughout the year including the colder months although they were only recovered from 94.9% of seawater and 92.3% of sediment samples. Throughout the surveillance, 96 isolates were subjected to specific PCR for virulence genes and none tested positive for either. The common understanding that consuming poorly cooked mussels only represents a risk of infection during summer vacations therefore is challenged. Further investigations with V. parahaemolyticus using RAPD-PCR cluster analysis showed a genetically diverse population. There was no distinct clustering for “environmental” or “clinical” reference strains although a wide variability and heterogeneity agreed with other reports. Continued surveillance of isolates to allay public health risks are justified since geographical distribution and composition of V. parahaemolyticus varies with Future Ocean warming and the potential of environmental strains to acquire virulence genes from pathogenic isolates. The prospects for intervention by phage-mediated biocontrol to reduce or eradicate V. parahaemolyticus in mussels was also investigated. Bacteriophages isolated from enriched samples collected from the river Humber were assessed for their ability to inhibit the growth of V. parahaemolyticus strains in-vitro and in-vivo (with live mussels). V. parahaemolyticus were significantly reduced in-vitro, by an average of 1 log−2

  19. Heterospecific discrimination of Poecile vocalizations by zebra finches (Taeniopygia guttata).

    PubMed

    Guillette, Lauren M; Hoeschele, Marisa; Hahn, Allison H; Sturdy, Christopher B

    2013-08-01

    Previous perceptual research with black-capped and mountain chickadees has demonstrated that the D note of the namesake chick-a-dee call controlled species-based discrimination compared to other note types in this call. In the current experiment, we sought to determine whether discrimination performance of the chickadees was controlled by stimulus-specific properties or due to learning through experience. To accomplish this, we tested zebra finches, a songbird species that is distantly related to chickadees, and also unfamiliar with black-capped and mountain chickadee vocalizations, on the same species-based discrimination on which black-capped and mountain chickadees were previously trained. We found that zebra finches learned the discrimination in the fewest number of trials with the D note, compared to other note types (i.e., the A, B, and C notes). In addition, we compared the current results to earlier work and found that zebra finches learned the discrimination in fewer trials compared to black-capped chickadees, and, across all species, males learned the discrimination in fewer trials than females. We discuss the roles that acoustic complexity and learning play in classification of the three species of songbirds tested. More generally, these results point to the benefits derived from testing members of each sex in species that vary in their natural history, vocal output, and phylogenetic relatedness as a means to uncover the mechanisms underlying acoustic communication. (PsycINFO Database Record (c) 2013 APA, all rights reserved).

  20. Microplastics in mussels along the coastal waters of China.

    PubMed

    Li, Jiana; Qu, Xiaoyun; Su, Lei; Zhang, Weiwei; Yang, Dongqi; Kolandhasamy, Prabhu; Li, Daoji; Shi, Huahong

    2016-07-01

    Microplastic has been confirmed as an emerging pollutant in marine environments. One of the primary environmental risks of microplastics is their bioavailability for aquatic organisms. Bivalves are of particular interest because their extensive filter-feeding activity exposes them directly to microplastics present in the water column. In the present study, we investigated microplastic pollution in mussels (Mytilus edulis) from 22 sites along 12,400 mile coastlines of China in 2015. The number of total microplastics varied from 0.9 to 4.6 items/g and from 1.5 to 7.6 items/individual. M. edulis contained more microplastics (2.7 items/g) in wild groups than that (1.6 items/g) in farmed groups. The abundance of microplastics was 3.3 items/g in mussels from the areas with intensive human activities and significantly higher than that (1.6 items/g) with less human activities. The most common microplastics were fibers, followed by fragments. The proportion of microplastics less than 250 μm in size arranged from 17% to 79% of the total microplastics. Diatom was distinguished from microplastics in mussels for the first time using Scanning Electron Microscope. Our results suggested that the numbers of microplastic kept within a relatively narrow range in mussels and were closely related to the contamination of the environments. We proposed that mussels could be used as a potential bioindicator of microplastic pollution of the coastal environment. Copyright © 2016 Elsevier Ltd. All rights reserved.

  1. Quality of public information matters in mate-choice copying in female zebra finches.

    PubMed

    Kniel, Nina; Schmitz, Jennifer; Witte, Klaudia

    2015-01-01

    Mate-choice copying is a form of social learning in which an individual gains information about potential mates by observing conspecifics. However, it is still unknown what kind of information drives the decision of an individual to copy the mate choice of others. Among zebra finches (Taeniopygia guttata castanotis), only females (not males) copy the mate choice of others. We tested female zebra finches in a binary choice test where they, first, could choose between two males of different phenotypes: one unadorned male and one male artificially adorned with a red feather on the forehead. After this mate-choice test, females could observe a single unadorned male and a pair of zebra finches, i.e. a wild-type female and her adorned mate. Pair interactions were either restricted to acoustic and visual communication (clear glass screen between pair mates) or acoustic communication alone (opaque screen between pair mates). After the observation period, females could again choose between new males of the two phenotypes in a second mate-choice test. In experiments with a clear glass screen, time spent with the respective males changed between the two mate-choice tests, and females preferred adorned over unadorned males during the second mate-choice test. In experiments with an opaque screen, time spent with the respective males did not change between the two mate-choice tests, although females lost an initial preference for unadorned males. Our results demonstrate that the quality of the received public information (visual and acoustic interaction of the observed pair) influences mate-choice copying in female zebra finches.

  2. ZENK expression following conspecific and heterospecific playback in the zebra finch auditory forebrain.

    PubMed

    Scully, Erin N; Hahn, Allison H; Campbell, Kimberley A; McMillan, Neil; Congdon, Jenna V; Sturdy, Christopher B

    2017-07-28

    Zebra finches (Taeniopygia guttata) are sexually dimorphic songbirds, not only in appearance but also in vocal production: while males produce both calls and songs, females only produce calls. This dimorphism provides a means to contrast the auditory perception of vocalizations produced by songbird species of varying degrees of relatedness in a dimorphic species to that of a monomorphic species, species in which both males and females produce calls and songs (e.g., black-capped chickadees, Poecile atricapillus). In the current study, we examined neuronal expression after playback of acoustically similar hetero- and conspecific calls produced by species of differing phylogenetic relatedness to our subject species, zebra finch. We measured the immediate early gene (IEG) ZENK in two auditory areas of the forebrain (caudomedial mesopallium, CMM, and caudomedial nidopallium, NCM). We found no significant differences in ZENK expression in either male or female zebra finches regardless of playback condition. We also discuss comparisons between our results and the results of a previous study conducted by Avey et al. [1] on black-capped chickadees that used similar stimulus types. These results are consistent with the previous study which also found no significant differences in expression following playback of calls produced by various heterospecific species and conspecifics [1]. Our results suggest that, similar to black-capped chickadees, IEG expression in zebra finch CMM and NCM is tied to the acoustic similarity of vocalizations and not the phylogenetic relatedness of the species producing the vocalizations. Copyright © 2017 Elsevier B.V. All rights reserved.

  3. Song Decrystallization in Adult Zebra Finches Does Not Require the Song Nucleus NIf

    PubMed Central

    Roy, Arani; Mooney, Richard

    2009-01-01

    In adult male zebra finches, transecting the vocal nerve causes previously stable (i.e., crystallized) song to slowly degrade, presumably because of the resulting distortion in auditory feedback. How and where distorted feedback interacts with song motor networks to induce this process of song decrystallization remains unknown. The song premotor nucleus HVC is a potential site where auditory feedback signals could interact with song motor commands. Although the forebrain nucleus interface of the nidopallium (NIf) appears to be the primary auditory input to HVC, NIf lesions made in adult zebra finches do not trigger song decrystallization. One possibility is that NIf lesions do not interfere with song maintenance, but do compromise the adult zebra finch's ability to express renewed vocal plasticity in response to feedback perturbations. To test this idea, we bilaterally lesioned NIf and then transected the vocal nerve in adult male zebra finches. We found that bilateral NIf lesions did not prevent nerve section–induced song decrystallization. To test the extent to which the NIf lesions disrupted auditory processing in the song system, we made in vivo extracellular recordings in HVC and a downstream anterior forebrain pathway (AFP) in NIf-lesioned birds. We found strong and selective auditory responses to the playback of the birds' own song persisted in HVC and the AFP following NIf lesions. These findings suggest that auditory inputs to the song system other than NIf, such as the caudal mesopallium, could act as a source of auditory feedback signals to the song motor network. PMID:19515953

  4. Song decrystallization in adult zebra finches does not require the song nucleus NIf.

    PubMed

    Roy, Arani; Mooney, Richard

    2009-08-01

    In adult male zebra finches, transecting the vocal nerve causes previously stable (i.e., crystallized) song to slowly degrade, presumably because of the resulting distortion in auditory feedback. How and where distorted feedback interacts with song motor networks to induce this process of song decrystallization remains unknown. The song premotor nucleus HVC is a potential site where auditory feedback signals could interact with song motor commands. Although the forebrain nucleus interface of the nidopallium (NIf) appears to be the primary auditory input to HVC, NIf lesions made in adult zebra finches do not trigger song decrystallization. One possibility is that NIf lesions do not interfere with song maintenance, but do compromise the adult zebra finch's ability to express renewed vocal plasticity in response to feedback perturbations. To test this idea, we bilaterally lesioned NIf and then transected the vocal nerve in adult male zebra finches. We found that bilateral NIf lesions did not prevent nerve section-induced song decrystallization. To test the extent to which the NIf lesions disrupted auditory processing in the song system, we made in vivo extracellular recordings in HVC and a downstream anterior forebrain pathway (AFP) in NIf-lesioned birds. We found strong and selective auditory responses to the playback of the birds' own song persisted in HVC and the AFP following NIf lesions. These findings suggest that auditory inputs to the song system other than NIf, such as the caudal mesopallium, could act as a source of auditory feedback signals to the song motor network.

  5. Variation in abundance of Pacific Blue Mussel (Mytilus trossulus) in the Northern Gulf of Alaska, 2006-2015

    NASA Astrophysics Data System (ADS)

    Bodkin, James L.; Coletti, Heather A.; Ballachey, Brenda E.; Monson, Daniel H.; Esler, Daniel; Dean, Thomas A.

    2018-01-01

    Mussels are conspicuous and ecologically important components of nearshore marine communities around the globe. Pacific blue mussels (Mytilus trossulus) are common residents of intertidal habitats in protected waters of the North Pacific, serving as a conduit of primary production to a wide range of nearshore consumers including predatory invertebrates, sea ducks, shorebirds, sea otters, humans, and other terrestrial mammals. We monitored seven metrics of intertidal Pacific blue mussel abundance at five sites in each of three regions across the northern Gulf of Alaska: Katmai National Park and Preserve (Katmai) (2006-2015), Kenai Fjords National Park (Kenai Fjords) (2008-2015) and western Prince William Sound (WPWS) (2007-2015). Metrics included estimates of: % cover at two tide heights in randomly selected rocky intertidal habitat; and in selected mussel beds estimates of: the density of large mussels (≥ 20 mm); density of all mussels > 2 mm estimated from cores extracted from those mussel beds; bed size; and total abundance of large and all mussels, i.e. the product of density and bed size. We evaluated whether these measures of mussel abundance differed among sites or regions, whether mussel abundance varied over time, and whether temporal patterns in abundance were site specific, or synchronous at regional or Gulf-wide spatial scales. We found that, for all metrics, mussel abundance varied on a site-by-site basis. After accounting for site differences, we found similar temporal patterns in several measures of abundance (both % cover metrics, large mussel density, large mussel abundance, and mussel abundance estimated from cores), in which abundance was initially high, declined significantly over several years, and subsequently recovered. Averaged across all sites, we documented declines of 84% in large mussel abundance through 2013 with recovery to 41% of initial abundance by 2015. These findings suggest that factors operating across the northern Gulf of

  6. Evaluation of relocation of unionid mussels to in situ refugia

    USGS Publications Warehouse

    Cope, W.G.; Hove, M.C.; Waller, D.L.; Hornbach, D.J.; Bartsch, M.R.; Cunningham, L.A.; Dunn, H.L.; Kapuscinski, A.R.

    2003-01-01

    The aim of this study was to evaluate the recovery and survival of four species of unionid mussles [pimpleback, Quadrula pustulosa pustulosa (I. Lea, 1831); spike, Elliptio dilatata (Rafinesque, 1820); Higgins eye, Lampsilis higginsii (I. Lea, 1857); and pocketbook, Lampsilis cardium (Rafinesque, 1820)] that were experimentally relocated to in situ refugia in the St Croix River of Minnesota and Wisconsin, USA. In 1996, 150 mussels of each of the first three species (450 total) were relocated to three 5 x 5 m study grids (Site A), one near Lakeland, Minnesota, which served as a source-site control, and two in the experimental refuge 48 km upstream, near Franconia, Minnesota. In a second relocation in 1997, L. Cardium was substituted for L. Higginsii and 150 mussels of this and each of the other two species (450 total), were relocated to two study grids (Site B). The source site control was near Sunrise, Minnesota and the experimental refuge was 14 km downstream near Almelund, Minnesota. Mussel recovery, survival and substratum characteristics were evaluated annually at Site A for 2 years and for 3 years at Site B. Mean annual recovery of all three species ranged from 90 to 100% at Site A, and from 34 to 70% at site B. The mean annual survival of recaptured mussels ranged from 85 to 100% at Site A, and from 88 to 100% at Site B. The textural characteristics of the substratum differed significantly between the control and the two refuge locations at the beginning of the study, but did not differ from this initial status among subsequent years at Site A. At Site B, there was a significant shift in textural characteristics from large to smaller fractions over the four years. The relatively high survival of mussels during this study demonstrates the importance of proper handling and transport protocols when relocating mussels and the selection of suitable relocation habitat with stable substratum. When established correctly, in situ refugia may be a viable tool for

  7. Evaluation of relocation of unionid mussels to in situ refugia

    USGS Publications Warehouse

    Cope, W.G.; Hove, M.C.; Waller, D.L.; Hornbach, D.J.; Bartsch, M.R.; Cunningham, L.A.; Dunn, H.L.; Kapuscinski, A.R.

    2003-01-01

    The aim of this study was to evaluate the recovery and survival of four species of unionid mussles [pimpleback, Quadrula pustulosa pustulosa (I. Lea, 1831); spike, Elliptio dilatata (Rafinesque, 1820); Higgins eye, Lampsilis higginsii (I. Lea, 1857); and pocketbook, Lampsilis cardium (Rafinesque, 1820)] that were experimentally relocated to in situ refugia in the St Croix River of Minnesota and Wisconsin, USA. In 1996, 150 mussels of each of the first three species (450 total) were relocated to three 5 ?? 5 m study grids (Site A), one near Lakeland, Minnesota, which served as a source-site control, and two in the experimental refuge 48 km upstream, near Franconia, Minnesota. In a second relocation in 1997, L. cardium was substituted for L. higginsii and 150 mussels of this and each of the other two species (450 total), were relocated to two study grids (Site B). The source site control was near Sunrise, Minnesota and the experimental refuge was 14 km downstream near Almelund, Minnesota. Mussel recovery, survival and substratum characteristics were evaluated annually at Site A for 2 years and for 3 years at Site B. Mean annual recovery of all three species ranged from 90 to 100% at Site A, and from 34 to 70% at site B. The mean annual survival of recaptured mussels ranged from 85 to 100% at Site A, and from 88 to 100% at Site B. The textural characteristics of the substratum differed significantly between the control and the two refuge locations at the beginning of the study, but did not differ from this initial status among subsequent years at Site A. At Site B, there was a significant shift in textural characteristics from large to smaller fractions over the four years. The relatively high survival of mussels during this study demonstrates the importance of proper handling and transport protocols when relocating mussels and the selection of suitable relocation habitat with stable substratum. When established correctly, in situ refugia may be a viable tool for

  8. Pervasive hydrologic effects on freshwater mussels and riparian trees in southeastern floodplain ecosystems

    Treesearch

    Andrew L. Rypel; Wendell R. Haag; Robert H. Findlay

    2009-01-01

    We present long-term growth trends for 13 freshwater mussel species from two unregulated rivers and one regulated river in the southeastern U.S. Coastal Plain. We also collected baldcypress (Taxodium distichum (L.) Rich.) tree cores adjacent to mussel collection sites in one river and directly compared tree and mussel chronologies in this river. To extend our analysis...

  9. Effects of carbon dioxide on juveniles of the freshwater mussel (Lampsilis siliquoidea [Unionidae])

    USGS Publications Warehouse

    Waller, Diane L.; Bartsch, Michelle; Fredricks, Kim; Bartsch, Lynn; Schleis, Sue M.; Lee, Sheldon

    2017-01-01

    Carbon dioxide (CO2) has shown promise as a tool to control movements of invasive Asian carp, but its effects on native freshwater biota have not been well studied. The authors evaluated lethal and sublethal responses of juvenile fatmucket (Lampsilis siliquoidea) mussels to CO2 at levels (43–269 mg/L, mean concentration) that bracket concentrations effective for deterring carp movement. The 28-d lethal concentration to 50% of the mussels was 87.0 mg/L (95% confidence interval [CI] 78.4–95.9) and at 16-d postexposure, 76.0 mg/L (95% CI 62.9–90.3). A proportional hazards regression model predicted that juveniles could not survive CO2 concentrations >160 mg/L for more than 2 wk or >100 mg/L CO2 for more than 30 d. Mean shell growth was significantly lower for mussels that survived CO2 treatments. Growth during the postexposure period did not differ among treatments, indicating recovery of the mussels. Also, CO2 caused shell pitting and erosion. Behavioral effects of CO2 included movement of mussels to the substrate surface and narcotization at the highest concentrations. Mussels in the 110 mg/L mean CO2treatment had the most movements in the first 3 d of exposure. If CO2 is infused continuously as a fish deterrent, concentrations <76 mg/L are recommended to prevent juvenile mussel mortality and shell damage. Mussels may survive and recover from brief exposure to higher concentrations.

  10. Flexibility of Physiological Traits Underlying Inter-Individual Growth Differences in Intertidal and Subtidal Mussels Mytilusgalloprovincialis

    PubMed Central

    Fernández-Reiriz, María José; Irisarri, Jade; Labarta, Uxio

    2016-01-01

    Mussel seed (Mytilusgalloprovincialis) gathered from the intertidal and subtidal environments of a Galician embayment (NW, Spain) were maintained in the laboratory during five months to select fast (F) and slow (S) growing mussels. The physiological basis underlying inter-individual growth variations were compared for F and S mussels from both origins. Fast growing seemed to be a consequence of greater energy intake (20% higher clearance and ingestion rate) and higher food absorption rate coupled with low metabolic costs. The enhanced energy absorption (around 65% higher) resulted in 3 times higher Scope for Growth in F mussels (20.5±4.9 J h−1) than S individuals (7.3±1.1 J h−1). The higher clearance rate of F mussels appears to be linked with larger gill filtration surface compared to S mussels. Intertidal mussels showed higher food acquisition and absorption per mg of organic weight (i.e. mass-specific standardization) than subtidal mussels under the optimal feeding conditions of the laboratory. However, the enhanced feeding and digestive rates were not enough to compensate for the initial differences in tissue weight between mussels of similar shell length collected from the intertidal and subtidal environments. At the end of the experiment, subtidal individuals had higher gill efficiency, which probably lead to higher total feeding and absorption rates relative to intertidal individuals. PMID:26849372

  11. Variation in fecundity and other reproductive traits in freshwater mussels

    Treesearch

    Wendell R. Haag; J. Leann Staton

    2003-01-01

    1. Life histories of the highly diverse and endangered North American freshwater mussel fauna are poorly known. We investigated reproductive traits of eight riverine mussel species in Alabama and Mississippi, U.S.A.: Amblema plicata, Elliptio arca, Fusconaia cerina, Lampsilis ornata, Obliquaria reflexa, Pleurobema decisum, Quadrula asperata and

  12. Response of Growth and Density of a Population of Geukensia demissa to Land-Derived Nitrogen Loading, in Waquoit Bay, Massachusetts

    NASA Astrophysics Data System (ADS)

    Evgenidou, A.; Valiela, I.

    2002-07-01

    Nutrient enrichment is a widespread phenomenon affecting coastal waters, including salt marshes. As land-derived nitrogen loading in estuarine waters increases, chlorophyll concentrations in the water also increase. We hypothesized that such increases might increase growth of the food-limited population of Geukensia demissa, which is a dominant component of salt marshes. To test this, we conducted a regional scale experiment in three estuaries of Waquoit Bay, Massachusetts that receive different nitrogen loading rates. A stable isotope experiment on mussel tissues and on particulate organic matter (POM) showed that mussels within an estuary fed on POM characteristic of that estuary, demonstrating the direct linkage between POM and mussels within an estuary. In addition, we measured age-specific shell growth rates of mussel populations using two different methods: indirectly, shell growth of mussels indicated by internal shell-lines was measured by fitting the data to the von Bertalanffy equation, and directly, mussels were transplanted from one estuary to the other two, and their actual shell growth rates after 80 days were measured. Growth rates of mussels in the Waquoit Bay estuaries varied with age of the mussel, tidal elevation, and with mean concentration of chlorophyll in the water. Mussels grew best in the lower intertidal zone, at the marsh banks. Young mussels grew faster than older mussels. Growth rates increased in response to presumed greater food supply across the estuaries, only for younger mussels. The significant differences we found among the mussels from different estuaries indicate a response to higher concentrations of food particles available in estuaries subject to higher nitrogen loads.

  13. The perception of regularity in an isochronous stimulus in zebra finches (Taeniopygia guttata) and humans.

    PubMed

    van der Aa, Jeroen; Honing, Henkjan; ten Cate, Carel

    2015-06-01

    Perceiving temporal regularity in an auditory stimulus is considered one of the basic features of musicality. Here we examine whether zebra finches can detect regularity in an isochronous stimulus. Using a go/no go paradigm we show that zebra finches are able to distinguish between an isochronous and an irregular stimulus. However, when the tempo of the isochronous stimulus is changed, it is no longer treated as similar to the training stimulus. Training with three isochronous and three irregular stimuli did not result in improvement of the generalization. In contrast, humans, exposed to the same stimuli, readily generalized across tempo changes. Our results suggest that zebra finches distinguish the different stimuli by learning specific local temporal features of each individual stimulus rather than attending to the global structure of the stimuli, i.e., to the temporal regularity. Copyright © 2015 Elsevier B.V. All rights reserved.

  14. Characterization of host plant resistance to zebra chip disease from species-derived potato genotypes and the identification of new sources of zebra chip resistance

    USDA-ARS?s Scientific Manuscript database

    ‘Candidatus Liberibacter solanacearum’ (Lso), an uncultivable phloem-limited phytopathogenic bacterium, is known to be associated with Zebra Chip disease (ZC), which represents a major threat to potato production in the US and elsewhere. This pathogen is transmitted by the phloem-feeding potato psyl...

  15. Mussel beds are biological power stations on intertidal flats

    NASA Astrophysics Data System (ADS)

    Engel, Friederike G.; Alegria, Javier; Andriana, Rosyta; Donadi, Serena; Gusmao, Joao B.; van Leeuwe, Maria A.; Matthiessen, Birte; Eriksson, Britas Klemens

    2017-05-01

    Intertidal flats are highly productive areas that support large numbers of invertebrates, fish, and birds. Benthic diatoms are essential for the function of tidal flats. They fuel the benthic food web by forming a thin photosynthesizing compartment in the top-layer of the sediment that stretches over the vast sediment flats during low tide. However, the abundance and function of the diatom film is not homogenously distributed. Recently, we have realized the importance of bivalve reefs for structuring intertidal ecosystems; by creating structures on the intertidal flats they provide habitat, reduce hydrodynamic stress and modify the surrounding sediment conditions, which promote the abundance of associated organisms. Accordingly, field studies show that high chlorophyll a concentration in the sediment co-vary with the presence of mussel beds. Here we present conclusive evidence by a manipulative experiment that mussels increase the local biomass of benthic microalgae; and relate this to increasing biomass of microalgae as well as productivity of the biofilm across a nearby mussel bed. Our results show that the ecosystem engineering properties of mussel beds transform them into hot spots for primary production on tidal flats, highlighting the importance of biological control of sedimentary systems.

  16. In vitro encystment of Himasthla elongata cercariae (Digenea, Echinostomatidae) in the haemolymph of blue mussels Mytilus edulis as a tool for assessing cercarial infectivity and molluscan susceptibility.

    PubMed

    Levakin, I A; Losev, E A; Nikolaev, K E; Galaktionov, K V

    2013-06-01

    Infectivity of Himasthla elongata cercariae to mussels, their second intermediate hosts, and resistance by these hosts to infection were assessed on the basis of the cercariae's ability to encyst in mussel haemolymph in vitro. A series of experimental in vivo infections of mussels with batches of cercariae, each batch released from a different single infected mollusc and referred to as a clone (due to their shared genotype), demonstrated that the results of the in vitro tests corresponded to the actual indices of infectivity/susceptibility of the parasites and their hosts. Most cercarial clones had high infectivity, with a few clones having very high or, at the other extreme, very low infectivity. A similar pattern was revealed in mussel resistance to cercarial infection. Most of the molluscs tested were moderately susceptible to cercarial infection, but at each extreme a small fraction (less than 10%) displayed very high or very low susceptibility. It was shown that there were no totally compatible or totally incompatible 'cercaria clone/mussel' combinations. Results obtained are compared with the data on intra-population variability using the characters parasite infectivity/host compatibility for trematode/mollusc-first intermediate host associations. Results are made relevant to actual infection levels in mussel settlements at the White Sea.

  17. Evaluating the use of side-scan sonar for detecting freshwater mussel beds in turbid river environments

    USGS Publications Warehouse

    Powers, Jarrod; Brewer, Shannon K.; Long, James M.; Campbell, Thomas

    2015-01-01

    Side-scan sonar is a valuable tool for mapping habitat features in many aquatic systems suggesting it may also be useful for locating sedentary biota. The objective of this study was to determine if side-scan sonar could be used to identify freshwater mussel (unionid) beds and the required environmental conditions. We used side-scan sonar to develop a series of mussel-bed reference images by placing mussel shells within homogenous areas of fine and coarse substrates. We then used side-scan sonar to map a 32-km river reach during spring and summer. Using our mussel-bed reference images, several river locations were identified where mussel beds appeared to exist in the scanned images and we chose a subset of sites (n = 17) for field validation. The validation confirmed that ~60% of the sites had mussel beds and ~80% had some mussels or shells present. Water depth was significantly related to our ability to predict mussel-bed locations: predictive ability was greatest at depths of 1–2 m, but decreased in water >2-m deep. We determined side-scan sonar is an effective tool for preliminary assessments of mussel presence during times when they are located at or above the substrate surface and in relatively fine substrates excluding fine silt.

  18. Trace metals and macroelements in mussels from Chinese coastal waters: National spatial patterns and normalization.

    PubMed

    Lu, Guang-Yuan; Wang, Wen-Xiong

    2018-06-01

    Metal contamination is one of the most ubiquitous and complex problems in the Chinese coastal environment. To explore the large-scale spatial patterns of bioavailable metals, we sampled three major mussels, including 784 blue mussels (Mytilus edulis Linnaeus, 1758) of 14 sites, 224 hard-shelled mussels (Mytilus unguiculatus Valenciennes, 1858) of 4 sites, and 392 green mussels (Perna viridis (Linnaeus, 1758)) of 7 sites, ranging from temperate to tropical coastlines of China, during August and September 2015. The concentrations of macroelements (Na, K, Ca, Mg, and P) and toxic trace metals (Ag, Cd, Cr, Cu, Ni, Pb, Ti, and Zn) in the mussel's whole soft tissues were determined. Among the four Chinese coastal basins, Cd, Ti and Cr in the mussel tissues were the highest at Bohai Sea (BS) and Yellow Sea (YS), and Cu, Ni, Pb and Ag in the mussel tissues were the highest at East China Sea (ECS) and South China Sea (SCS). Zinc concentrations in mussels from YS were significantly higher than those from the other regions. Given the variability of environmental conditions such as salinity and nutrients, we further normalized the measured tissue metal concentrations with tissue Na and P levels. After Na normalization as the salinity proxy, the variability of Cd, Cu, Zn, Ag, and Ni was reduced. Trace elements accumulation in the mussel tissues was significantly related to both macroelements (Na or P) and body dry weight. The present study demonstrated that nonlinear optimization of different elements was necessary in assessing metal bioaccumulation patterns in marine mussels at a large spatial scale. Copyright © 2018 Elsevier B.V. All rights reserved.

  19. Lysosomal responses to heat-shock of seasonal temperature extremes in Cd-exposed mussels.

    PubMed

    Múgica, M; Izagirre, U; Marigómez, I

    2015-07-01

    The present study was aimed at determining the effect of temperature extremes on lysosomal biomarkers in mussels exposed to a model toxic pollutant (Cd) at different seasons. For this purpose, temperature was elevated 10°C (from 12°C to 22°C in winter and from 18°C to 28°C in summer) for a period of 6h (heat-shock) in control and Cd-exposed mussels, and then returned back to initial one. Lysosomal membrane stability and lysosomal structural changes in digestive gland were investigated. In winter, heat-shock reduced the labilisation period (LP) of the lysosomal membrane, especially in Cd-exposed mussels, and provoked transient lysosomal enlargement. LP values recovered after the heat-shock cessation but lysosomal enlargement prevailed in both experimental groups. In summer, heat-shock induced remarkable reduction in LP and lysosomal enlargement (more markedly in Cd-exposed mussels), which recovered within 3 days. Besides, whilst heat-shock effects on LP were practically identical for Cd-exposed mussels in winter and summer, the effects were longer-lasting in summer than in winter for control mussels. Thus, lysosomal responsiveness after heat-shock was higher in summer than in winter but recovery was faster as well, and therefore the consequences of the heat shock seem to be more decisive in winter. In contrast, inter-season differences were attenuated in the presence of Cd. Consequently, mussels seem to be better prepared in summer than in winter to stand short periods of abrupt temperature change; this is, however, compromised when mussels are exposed to pollutants such as Cd. Copyright © 2015 Elsevier B.V. All rights reserved.

  20. Mussel remains from prehistoric salt works, clarke county, Alabama

    USGS Publications Warehouse

    McGregor, S.W.; Dumas, A.A.

    2010-01-01

    Archaeological research at salt springs in Clarke County, AL (Tombigbee River drainage), documented bivalve mollusk exploitation by late prehistoric American Indians. A total of 582 valves representing 19 species of freshwater mussels (Unionidae) and an estuarine clam (Mactridae) from the Lower Salt Works Site (ca. A.D. 900-1550) and 41 valve fragments representing 6 mussel species from the Stimpson Site (ca. A.D. 1200-1550) were documented. The Lower Salt Works fauna was dominated numerically by Fusconaia ebena and Quadrula asperata, the dominant species reported during recent local surveys. The mussel species represented are known from medium to large streams in sand and gravel habitats and include four federally protected species and other species of conservation concern in Alabama. Results offer comparative data for other archaeological and ecological studies in the region.

  1. Housing conditions and sacrifice protocol affect neural activity and vocal behavior in a songbird species, the zebra finch (Taeniopygia guttata).

    PubMed

    Elie, Julie Estelle; Soula, Hédi Antoine; Trouvé, Colette; Mathevon, Nicolas; Vignal, Clémentine

    2015-12-01

    Individual cages represent a widely used housing condition in laboratories. This isolation represents an impoverished physical and social environment in gregarious animals. It prevents animals from socializing, even when auditory and visual contact is maintained. Zebra finches are colonial songbirds that are widely used as laboratory animals for the study of vocal communication from brain to behavior. In this study, we investigated the effect of single housing on the vocal behavior and the brain activity of male zebra finches (Taeniopygia guttata): male birds housed in individual cages were compared to freely interacting male birds housed as a social group in a communal cage. We focused on the activity of septo-hypothalamic regions of the "social behavior network" (SBN), a set of limbic regions involved in several social behaviors in vertebrates. The activity of four structures of the SBN (BSTm, medial bed nucleus of the stria terminalis; POM, medial preoptic area; lateral septum; ventromedial hypothalamus) and one associated region (paraventricular nucleus of the hypothalamus) was assessed using immunoreactive nuclei density of the immediate early gene Zenk (egr-1). We further assessed the identity of active cell populations by labeling vasotocin (VT). Brain activity was related to behavioral activities of birds like physical and vocal interactions. We showed that individual housing modifies vocal exchanges between birds compared to communal housing. This is of particular importance in the zebra finch, a model species for the study of vocal communication. In addition, a protocol that daily removes one or two birds from the group affects differently male zebra finches depending of their housing conditions: while communally-housed males changed their vocal output, brains of individually housed males show increased Zenk labeling in non-VT cells of the BSTm and enhanced correlation of Zenk-revealed activity between the studied structures. These results show that

  2. Canning process that diminishes paralytic shellfish poison in naturally contaminated mussels (Mytilus galloprovincialis).

    PubMed

    Vieites, J M; Botana, L M; Vieytes, M R; Leira, F J

    1999-05-01

    Changes in toxin profile and total toxicity levels of paralytic shellfish poison (PSP)-containing mussels were monitored during the standard canning process of pickled mussels and mussels in brine using mouse bioassays and high-performance liquid chromatography. Detoxification percentages for canned mussel meat exceeded 50% of initial toxicity. Total toxicity reduction did not fully correspond to toxin destruction, which was due to the loss of PSP to cooking water and packing media of the canned product. Significant differences in detoxification percentages were due to changes in toxin profile during heat treatment in packing media. Toxin conversion phenomena should be determined to validate detoxification procedures in the canning industry.

  3. Comparative Cytogenetics between Two Important Songbird, Models: The Zebra Finch and the Canary

    PubMed Central

    dos Santos, Michelly da Silva; Kretschmer, Rafael; Frankl-Vilches, Carolina; Bakker, Antje; Gahr, Manfred; O´Brien, Patricia C. M.; Ferguson-Smith, Malcolm A.

    2017-01-01

    Songbird species (order Passeriformes, suborder Oscines) are important models in various experimental fields spanning behavioural genomics to neurobiology. Although the genomes of some songbird species were sequenced recently, the chromosomal organization of these species is mostly unknown. Here we focused on the two most studied songbird species in neuroscience, the zebra finch (Taeniopygia guttata) and the canary (Serinus canaria). In order to clarify these issues and also to integrate chromosome data with their assembled genomes, we used classical and molecular cytogenetics in both zebra finch and canary to define their chromosomal homology, localization of heterochromatic blocks and distribution of rDNA clusters. We confirmed the same diploid number (2n = 80) in both species, as previously reported. FISH experiments confirmed the occurrence of multiple paracentric and pericentric inversions previously found in other species of Passeriformes, providing a cytogenetic signature for this order, and corroborating data from in silico analyses. Additionally, compared to other Passeriformes, we detected differences in the zebra finch karyotype concerning the morphology of some chromosomes, in the distribution of 5S rDNA clusters, and an inversion in chromosome 1. PMID:28129381

  4. Variation in abundance of Pacific Blue Mussel (Mytilus trossulus) in the Northern Gulf of Alaska, 2006–2015

    USGS Publications Warehouse

    Bodkin, James L.; Coletti, Heather A.; Ballachey, Brenda E.; Monson, Daniel; Esler, Daniel N.; Dean, Thomas A.

    2017-01-01

    Mussels are conspicuous and ecologically important components of nearshore marine communities around the globe. Pacific blue mussels (Mytilus trossulus) are common residents of intertidal habitats in protected waters of the North Pacific, serving as a conduit of primary production to a wide range of nearshore consumers including predatory invertebrates, sea ducks, shorebirds, sea otters, humans, and other terrestrial mammals. We monitored seven metrics of intertidal Pacific blue mussel abundance at five sites in each of three regions across the northern Gulf of Alaska: Katmai National Park and Preserve (Katmai) (2006–2015), Kenai Fjords National Park (Kenai Fjords) (2008–2015) and western Prince William Sound (WPWS) (2007–2015). Metrics included estimates of: % cover at two tide heights in randomly selected rocky intertidal habitat; and in selected mussel beds estimates of: the density of large mussels (≥ 20 mm); density of all mussels > 2 mm estimated from cores extracted from those mussel beds; bed size; and total abundance of large and all mussels, i.e. the product of density and bed size. We evaluated whether these measures of mussel abundance differed among sites or regions, whether mussel abundance varied over time, and whether temporal patterns in abundance were site specific, or synchronous at regional or Gulf-wide spatial scales. We found that, for all metrics, mussel abundance varied on a site-by-site basis. After accounting for site differences, we found similar temporal patterns in several measures of abundance (both % cover metrics, large mussel density, large mussel abundance, and mussel abundance estimated from cores), in which abundance was initially high, declined significantly over several years, and subsequently recovered. Averaged across all sites, we documented declines of 84% in large mussel abundance through 2013 with recovery to 41% of initial abundance by 2015. These findings suggest that factors operating across the northern Gulf

  5. [Resection of the recurrent third branchial fistula under gastroscope with assistance of yellow zebra guidewire].

    PubMed

    Feng, X; Huang, Z C; Tao, F; Ou, X L

    2016-02-01

    To investigate clinical aspects and a new operative method for resecting third branchial fistula. The clinical aspects of 4 patients with third branchial fistula were retrospectively analyzed. It is difficult to locate the inner orifice of fistula through neck path due to tiny diameter of inner orifice. The inner orifice could be found and closed effectively by inserting yellow zebra guidewire from sinus piriformis with gastroscope. The mucous membrane of sinus piriformis could not be damaged due to the soft pointed end of yellow zebra guidewire. 4 cases were treated successfully without pharyngeal fistula or recurrent laryngeal nerve injury. No recurrent infections were found in all cases with follows-up of 6-66 months. Ineffectiveness of radiography with meglumine diatrizoate or oral administration of methylene blue before operation indicates tiny fistula. In this case, resection of third branchial fistula with the assistance of gastroscope and yellow zebra guidewire under general anesthesia can be performed. This innovative method of diagnosis and treatment is worth of application clinically.

  6. Seasonal and species-specific patterns in abundance of freshwater mussel glochidia in stream drift

    Treesearch

    Jacob J. Culp; Wendell R. Haag; D. Albrey Arrington; Thomas B. Kennedy

    2011-01-01

    Abstract. We examined seasonal patterns of abundance of mussel larvae (glochidia) in stream drift in a diverse, large-stream mussel assemblage in the Sipsey River, Alabama, across 1 y. We used recently developed techniques for glochidial identification combined with information about mussel fecundity and benthic assemblages to evaluate how well observed glochidial...

  7. Biomarker responses of mussels exposed to earthquake disturbances

    NASA Astrophysics Data System (ADS)

    Chandurvelan, Rathishri; Marsden, Islay D.; Glover, Chris N.; Gaw, Sally

    2016-12-01

    The green-lipped mussel, Perna canaliculus is recognised as a bioindicator of coastal contamination in New Zealand (NZ). Mussels (shell length 60-80 mm) were collected from three intertidal areas of Canterbury in the South Island of NZ prior to extreme earthquake disturbances on 22nd February 2011, and 9 months later in October 2011. Trace elements, including arsenic (As), cadmium (Cd), copper (Cu), lead (Pb), nickel (Ni), and zinc (Zn), were measured in the gills, digestive gland, foot and mantle. Metal levels in tissues were site specific, and mostly unaffected by earthquake disturbances. Physiological biomarkers were negatively affected by earthquake disturbances and mussels from the Port of Lyttelton had higher negative scope for growth post-earthquake. Metallothionein-like protein in the digestive gland correlated with metal content of tissues, as did catalase activity in the gill and lipid peroxidation values for the digestive gland. This research demonstrates that physiological and other biomarkers are effective at detecting the effects of multiple stressors following seismic disturbances.

  8. Infection patterns in white sea blue mussels Mytilus edulis of different age and size with metacercariae of Himasthla elongata (Echinostomatidae) and Cercaria parvicaudata (Renicolidae).

    PubMed

    Nikolaev, K E; Sukhotin, A A; Galaktionov, K V

    2006-07-11

    Infection of mussels Mytilus edulis L. by 2 trematode species was studied in a natural intertidal population in the Chupa inlet of the White Sea. The prevalence of metacercariae of Himasthla elongata (Mehlis, 1831) and Cercaria parvicaudata (Stunkard & Shaw, 1931) in mussels reached 100% in 3 to 4 yr old molluscs and remained at this level in older individuals. Infection intensity increased evenly with the age of the molluscan host, showing a tendency to decrease only in the oldest (9 yr old) mussels. These patterns of age dynamics of prevalence and infection intensity were associated with accumulation of trematode larvae in the course of the molluscs' lives. Ability of metacercariae to exist in mussels for long periods (at least 2.5 yr) was verified in the course of an experiment, during which infected molluscs were kept in a subtidal net cage. Decrease of infection intensity in the oldest individuals may reflect selective mortality of the most severely infected molluscs. Among mussels of the same age, higher infection intensity values occurred in larger individuals. This may be due to an enhanced pumping rate in large molluscs, which increases the probability of cercariae, free-living trematode larvae, infecting them via water currents.

  9. Accelerated Evolution of PAK3- and PIM1-like Kinase Gene Families in the Zebra Finch, Taeniopygia guttata

    PubMed Central

    Kong, Lesheng; Lovell, Peter V.; Heger, Andreas; Mello, Claudio V.; Ponting, Chris P.

    2010-01-01

    Genes encoding protein kinases tend to evolve slowly over evolutionary time, and only rarely do they appear as recent duplications in sequenced vertebrate genomes. Consequently, it was a surprise to find two families of kinase genes that have greatly and recently expanded in the zebra finch (Taeniopygia guttata) lineage. In contrast to other amniotic genomes (including chicken) that harbor only single copies of p21-activated serine/threonine kinase 3 (PAK3) and proviral integration site 1 (PIM1) genes, the zebra finch genome appeared at first to additionally contain 67 PAK3-like (PAK3L) and 51 PIM1-like (PIM1L) protein kinase genes. An exhaustive analysis of these gene models, however, revealed most to be incomplete, owing to the absence of terminal exons. After reprediction, 31 PAK3L genes and 10 PIM1L genes remain, and all but three are predicted, from the retention of functional sites and open reading frames, to be enzymatically active. PAK3L, but not PIM1L, gene sequences show evidence of recurrent episodes of positive selection, concentrated within structures spatially adjacent to N- and C-terminal protein regions that have been discarded from zebra finch PAK3L genes. At least seven zebra finch PAK3L genes were observed to be expressed in testis, whereas two sequences were found transcribed in the brain, one broadly including the song nuclei and the other in the ventricular zone and in cells resembling Bergmann's glia in the cerebellar Purkinje cell layer. Two PIM1L sequences were also observed to be expressed with broad distributions in the zebra finch brain, one in both the ventricular zone and the cerebellum and apparently associated with glial cells and the other showing neuronal cell expression and marked enrichment in midbrain/thalamic nuclei. These expression patterns do not correlate with zebra finch-specific features such as vocal learning. Nevertheless, our results show how ancient and conserved intracellular signaling molecules can be co

  10. Digital gene expression analysis of the zebra finch genome

    PubMed Central

    2010-01-01

    Background In order to understand patterns of adaptation and molecular evolution it is important to quantify both variation in gene expression and nucleotide sequence divergence. Gene expression profiling in non-model organisms has recently been facilitated by the advent of massively parallel sequencing technology. Here we investigate tissue specific gene expression patterns in the zebra finch (Taeniopygia guttata) with special emphasis on the genes of the major histocompatibility complex (MHC). Results Almost 2 million 454-sequencing reads from cDNA of six different tissues were assembled and analysed. A total of 11,793 zebra finch transcripts were represented in this EST data, indicating a transcriptome coverage of about 65%. There was a positive correlation between the tissue specificity of gene expression and non-synonymous to synonymous nucleotide substitution ratio of genes, suggesting that genes with a specialised function are evolving at a higher rate (or with less constraint) than genes with a more general function. In line with this, there was also a negative correlation between overall expression levels and expression specificity of contigs. We found evidence for expression of 10 different genes related to the MHC. MHC genes showed relatively tissue specific expression levels and were in general primarily expressed in spleen. Several MHC genes, including MHC class I also showed expression in brain. Furthermore, for all genes with highest levels of expression in spleen there was an overrepresentation of several gene ontology terms related to immune function. Conclusions Our study highlights the usefulness of next-generation sequence data for quantifying gene expression in the genome as a whole as well as in specific candidate genes. Overall, the data show predicted patterns of gene expression profiles and molecular evolution in the zebra finch genome. Expression of MHC genes in particular, corresponds well with expression patterns in other vertebrates

  11. Exploring the zebra finch Taeniopygia guttata as a novel animal model for the speech-language deficit of fragile X syndrome.

    PubMed

    Winograd, Claudia; Ceman, Stephanie

    2012-01-01

    Fragile X syndrome (FXS) is the most common cause of inherited intellectual disability and presents with markedly atypical speech-language, likely due to impaired vocal learning. Although current models have been useful for studies of some aspects of FXS, zebra finch is the only tractable lab model for vocal learning. The neural circuits for vocal learning in the zebra finch have clear relationships to the pathways in the human brain that may be affected in FXS. Further, finch vocal learning may be quantified using software designed specifically for this purpose. Knockdown of the zebra finch FMR1 gene may ultimately enable novel tests of therapies that are modality-specific, using drugs or even social strategies, to ameliorate deficits in vocal development and function. In this chapter, we describe the utility of the zebra finch model and present a hypothesis for the role of FMRP in the developing neural circuitry for vocalization.

  12. The effects of elevated water temperature on native juvenile mussels: implications for climate change

    USGS Publications Warehouse

    Ganser, Alissa M.; Newton, Teresa J.; Haro, Roger J.

    2013-01-01

    Native freshwater mussels are a diverse but imperiled fauna and may be especially sensitive to increasing water temperatures because many species already may be living near their upper thermal limits. We tested the hypothesis that elevated water temperatures (20, 25, 30, and 35°C) adversely affected the survival and physiology of 2-mo-old juvenile mussels (Lampsilis abrupta, Lampsilis siliquoidea, and Megalonaias nervosa) in 28-d laboratory experiments. The 28-d LT50s (lethal temperature affecting 50% of the population) ranged from 25.3 to 30.3°C across species, and were lowest for L. abrupta and L. siliquoidea. Heart rate of L. siliquoidea was not affected by temperature, but heart rate declined at higher temperatures in L. abrupta and M. nervosa. However, for both of these species, heart rate also declined steadily during the experiment and a strong temperature × time interaction was detected. Juvenile growth was low for all species in all treatments and did not respond directly to temperature, but growth of some species responded to a temperature × time interaction. Responses to thermal stress differed among species, but potential laboratory artifacts may limit applicability of these results to real-world situations. Environmentally relevant estimates of upper thermal tolerances in native mussels are urgently needed to assess the extent of assemblage changes that can be expected in response to global climate change.

  13. Noninvasive diffusive optical imaging of the auditory response to birdsong in the zebra finch

    PubMed Central

    Lee, James V.; Maclin, Edward L.; Low, Kathy A.; Gratton, Gabriele; Fabiani, Monica; Clayton, David F.

    2013-01-01

    Songbirds communicate by learned vocalizations with concomitant changes in neurophysiological and genomic activities in discrete parts of the brain. Here we tested a novel implementation of diffusive optical imaging (also known as diffuse optical imaging, DOI) for monitoring brain physiology associated with vocal signal perception. DOI noninvasively measures brain activity using red and near-infrared light delivered through optic fibers (optodes) resting on the scalp. DOI does not harm subjects, so it raises the possibility of repeatedly measuring brain activity and the effects of accumulated experience in the same subject over an entire life span, all while leaving tissue intact for further study. We developed a custom-made apparatus for interfacing optodes to the zebra finch (Taeniopygia guttata) head using 3D modeling software and rapid prototyping technology, and applied it to record responses to presentations of birdsong in isoflurane-anesthetized zebra finches. We discovered a subtle but significant difference between the hemoglobin spectra of zebra finches and mammals which has a major impact in how hemodynamic responses are interpreted in the zebra finch. Our measured responses to birdsong playback were robust, highly repeatable, and readily observed in single trials. Responses were complex in shape and closely paralleled responses described in mammals. They were localized to the caudal medial portion of the brain, consistent with response localization from prior gene expression, electrophysiological, and functional magnetic resonance imaging studies. These results define an approach for collecting neurophysiological data from songbirds that should be applicable to diverse species and adaptable for studies in awake behaving animals. PMID:23322445

  14. Mussel micronucleus cytome assay.

    PubMed

    Bolognesi, Claudia; Fenech, Michael

    2012-05-17

    The micronucleus (MN) assay is one of the most widely used genotoxicity biomarkers in aquatic organisms, providing an efficient measure of chromosomal DNA damage occurring as a result of either chromosome breakage or chromosome mis-segregation during mitosis. The MN assay is today applied in laboratory and field studies using hemocytes and gill cells from bivalves, mainly from the genera Mytilus. These represent 'sentinel' organisms because of their ability to survive under polluted conditions and to accumulate both organic and inorganic pollutants. Because the mussel MN assay also includes scoring of different cell types, including necrotic and apoptotic cells and other nuclear anomalies, it is in effect an MN cytome assay. The mussel MN cytome (MUMNcyt) assay protocol we describe here reports the recommended experimental design, sample size, cell preparation, cell fixation and staining methods. The protocol also includes criteria and photomicrographs for identifying different cell types and scoring criteria for micronuclei (MNi) and nuclear buds. The complete procedure requires approximately 10 h for each experimental point/sampling station (ten animals).

  15. Susceptibility of selected potato varieties to zebra chip potato disease

    USDA-ARS?s Scientific Manuscript database

    Zebra chip (ZC), an emerging and serious disease of potato has caused millions of dollars in losses to the potato industry in the United States, Mexico, Central America, and New Zealand. The disease has recently been associated with a previously undescribed species of liberibacter tentatively named ...

  16. Combined use of chemical, biochemical and physiological variables in mussels for the assessment of marine pollution along the N-NW Spanish coast.

    PubMed

    Bellas, Juan; Albentosa, Marina; Vidal-Liñán, Leticia; Besada, Victoria; Franco, M Ángeles; Fumega, José; González-Quijano, Amelia; Viñas, Lucía; Beiras, Ricardo

    2014-05-01

    This study undertakes an overall assessment of pollution in a large region (over 2500 km of coastline) of the N-NW Spanish coast, by combining the use of biochemical (AChE, GST, GPx) and physiological (SFG) responses to pollution, with chemical analyses in wild mussel populations (Mytilus galloprovincialis). The application of chemical analysis and biological techniques identified polluted sites and quantified the level of toxicity. High levels of pollutants were found in mussel populations located close to major cities and industrialized areas and, in general, average concentrations were higher in the Cantabrian than in the Iberian Atlantic coast. AChE activities ranged between 5.8 and 27.1 nmol/min/mg prot, showing inhibition in 12 sampling sites, according to available ecotoxicological criteria. GST activities ranged between 29.5 and 112.7 nmol/min/mg prot, and extreme variability was observed in GPx, showing activities between 2.6 and 64.5 nmol/min/mg prot. Regarding SFG, only 5 sites showed 'moderate stress' (SFG value below 20 J/g/h), and most sites presented a 'high potential growth' (>35 J/g/h) corresponding to a 'healthy state'. Multivariate statistical techniques applied to the chemical and biological data identified PCBs, organochlorine pesticides and BDEs as the main responsible of the observed toxicity. However, the alteration of biological responses caused by pollutants seems to be, in general, masked by biological variables, namely age and mussel condition, which have an effect on the mussels' response to pollutant exposure. Copyright © 2013 Elsevier Ltd. All rights reserved.

  17. Life stage sensitivity of the marine mussel Mytilus edulis to ammonia.

    PubMed

    Kennedy, Alan J; Lindsay, James H; Biedenbach, James M; Harmon, Ashley R

    2017-01-01

    Ammonia is an important contaminant to consider in all toxicity tests. It is especially important to consider the impacts of ammonia in test methods that use sensitive water column organisms exposed to sediments or sediment extracts, such as porewater and elutriate toxicity tests. Embryo-larval development toxicity tests, such as the 48-h method using Mytilus mussel species, are particularly sensitive to ammonia. To better understand the effect thresholds across different life stages of these mussels, 6 short-term (48-h) development toxicity tests and 3 21-d toxicity tests with different-sized juvenile mussels were conducted. Two of the juvenile mussel tests involved 21-d continuous chronic exposure to ammonia, whereas the third involved an acute 2-d ammonia exposure, followed by a 19-d recovery period. The embryo-larval development test method (50% effect concentration [EC50] = 0.14-0.18 mg/L un-ionized ammonia) was 2.5 times more sensitive than the juvenile mussel 21-d survival endpoint (50% lethal concentration = 0.39 mg/L un-ionized ammonia) and 2 times more sensitive than the most sensitive sublethal juvenile mussel endpoint (EC50 = 0.26 mg/L un-ionized ammonia). Further, it was found that the juveniles recovered from a 48-h exposure to un-ionized ammonia of up to 1.1 mg/L. The data generated suggest that the embryo development endpoint was sufficiently sensitive to un-ionized ammonia to protect the chronically exposed (21 d) juvenile mussels. Environ Toxicol Chem 2017;36:89-95. Published 2016 Wiley Periodicals Inc. on behalf of SETAC. This article is a US government work and, as such, is in the public domain in the United States of America. Published 2016 Wiley Periodicals Inc. on behalf of SETAC. This article is a US government work and, as such, is in the public domain in the United States of America.

  18. Caudal thoracic air sac cannulation in zebra finches for isoflurane anesthesia.

    PubMed

    Nilson, Paige Crystal; Teramitsu, Ikuko; White, Stephanie Ann

    2005-04-30

    Small songbirds such as the zebra finch are commonly used for studies on the neural mechanisms that underlie vocal learning. For these studies, survival surgeries are often performed that involve animal anesthesia and stereotaxic stabilization for localization of specific brain regions. Here we describe air sac cannulation as a novel method for delivering isoflurane gas to zebra finches for anesthesia during neurosurgery. Advantages of this method include that it leaves the bird's head free for stereotaxic targeting and does not interfere with the beak clamps that are often used to position and stabilize the head. It additionally allows for the use of the inhalant anesthetic, isoflurane, which is an appealing alternative to injectable anesthetics because it provides fast, minimally stressful induction, and low subject and personnel toxicity. The use of isoflurane also prevents overdosing and lengthy postoperative recovery times.

  19. Effects of temperature change on mussel, Mytilus.

    PubMed

    Zippay, Mackenzie L; Helmuth, Brian

    2012-09-01

    An increasing body of research has demonstrated the often idiosyncratic responses of organisms to climate-related factors, such as increases in air, sea and land surface temperatures, especially when coupled with non-climatic stressors. This argues that sweeping generalizations about the likely impacts of climate change on organisms and ecosystems are likely less valuable than process-based explorations that focus on key species and ecosystems. Mussels in the genus Mytilus have been studied for centuries, and much is known of their physiology and ecology. Like other intertidal organisms, these animals may serve as early indicators of climate change impacts. As structuring species, their survival has cascading impacts on many other species, making them ecologically important, in addition to their economic value as a food source. Here, we briefly review the categories of information available on the effects of temperature change on mussels within this genus. Although a considerable body of information exists about the genus in general, knowledge gaps still exist, specifically in our ability to predict how specific populations are likely to respond to the effects of multiple stressors, both climate and non-climate related, and how these changes are likely to result in ecosystem-level responses. Whereas this genus provides an excellent model for exploring the effects of climate change on natural and human-managed ecosystems, much work remains if we are to make predictions of likely impacts of environmental change on scales that are relevant to climate adaptation. © 2012 Wiley Publishing Asia Pty Ltd, ISZS and IOZ/CAS.

  20. Freshwater Mussels as Biological Sensors and Cyclers of Aquatic Nitrogen Constituents: An Experimental Investigation

    NASA Astrophysics Data System (ADS)

    Kruger, A.; Just, C. L.; Mudumbai, R.; Dasgupta, S.; Newton, T. J.; Durst, J.; Boddicker, M. D.; Diken, M. B.; Bril, J.; Baidoo-Williams, H. E.

    2011-12-01

    One of the most extensive manifestations of anthropogenic mismanagement of nitrogen is eutrophication of the Gulf of Mexico. Leaching and runoff transport nitrate compounds-excess agricultural fertilizer and animal waste-via the Mississippi River to the Gulf of Mexico. Phytoplankton then multiplies exponentially, and consumes most of the dissolved oxygen. This hypoxia kills fish and other organisms, leading to so-called dead zones in the Gulf that can cover 6,000-7,000 square miles. Dead zone mitigation plans call for coupling management actions with enhanced monitoring, modeling, and research on nitrogen delivery to, as well as processing within, the Mississippi River. Our vision is to create a biosensor network of native freshwater mussels in a major river to monitor, comprehend, and ultimately model key components of the nitrogen cycle. Native freshwater mussels are a guild of long-lived, suspension feeding bivalves that perform important ecological functions in aquatic systems. Mussels can influence nutrient cycling by transferring nutrients from the water column to the riverbed. A major problem for environmental scientists is that relatively little is known about the diurnal behaviors of freshwater mussels or the impacts these behaviors may have on the aquatic nitrogen cycle. Our multidisciplinary team is performing a series of laboratory experiments exploring the feasibility of using freshwater mussels as sensors of and capacitors for nitrates. For sensing, we place Hall-effect sensors on mussels to monitor the rhythmic opening and closing of their valves (gape). One shortcoming of previous work is that mussels were monitored in artificial conditions: glued fast in laboratory flumes, or tethered in constrained settings. To overcome this shortcoming, our team has built a mussel microhabitat with a constant river water feed stock, solar simulator, and a variety of water chemistry sensor. A main thrust of our work is to develop the technology to monitor mussel

  1. RIBBED MUSSEL NITROGEN ISOTOPE SIGNATURES REFLECT NITROGEN SOURCES IN COASTAL MARSHES

    EPA Science Inventory

    The stable nitrogen isotope ratio in tissue of the ribbed mussel (Geukensia demissa) was investigated as an indicator of the source of nitrogen inputs to coastal salt marshes. Initially, mussels were fed a diet of 15N-enriched algae in the laboratory to determine how the tissue n...

  2. Lethal and sub-lethal responses of native freshwater mussels exposed to granular Bayluscide®, a sea lamprey larvicide

    USGS Publications Warehouse

    Newton, Teresa; Boogaard, Michael A.; Gray, Brian R.; Hubert, Terrance D.; Schloesser, Nicholas

    2017-01-01

    The invasive sea lamprey (Petromyzon marinus) poses a substantial threat to fish communities in the Great Lakes. Efforts to control sea lamprey populations typically involve treating tributary streams with lampricides on a recurring cycle. The presence of a substantial population of larval sea lampreys in the aquatic corridor between Lakes Huron and Erie prompted managers to propose a treatment using the granular formulation of Bayluscide® that targets larval sea lampreys that reside in sediments. However, these treatments could cause adverse effects on native freshwater mussels—imperiled animals that also reside in sediments. We estimated the risk of mortality and sub-lethal effects among eight species of adult and sub-adult mussels exposed to Bayluscide® for durations up to 8 h to mimic field applications. Mortality was appreciable in some species, especially in sub-adults (range, 23–51%). The lethal and sub-lethal effects were positively associated with the duration of exposure in most species and life stage combinations. Estimates of the median time of exposure that resulted in lethal and sub-lethal effects suggest that sub-adults were often affected by Bayluscide® earlier than adults. Siphoning activity and burrowing position of mussels during exposure may have moderated the uptake of Bayluscide® and may have influenced lethal and sub-lethal responses. Given that the various species and life stages were differentially affected, it will be difficult to predict the effects of Bayluscide® treatments on mussels.

  3. Potato psyllid vector of zebra chip disease in Pacific Northwest

    USDA-ARS?s Scientific Manuscript database

    Zebra chip is a destructive disease of potatoes in the Pacific Northwest and other potato production regions of North America. The pathogen associated with this disease is transmitted by the potato psyllid. A team of researchers which included a scientist at the ARS in Wapato, WA updated an extens...

  4. Toxic effects of unresolved complex mixtures of aromatic hydrocarbons accumulated by mussels, Mytilus edulis, from contaminated field sites.

    PubMed

    Donkin, Peter; Smith, Emma L; Rowland, Steven J

    2003-11-01

    Exposure of marine mussels (Mytilus edulis) to an unresolved complex mixture (UCM) of aromatic hydrocarbons isolated from a crude oil has been shown to reduce their feeding rate by 40%. The present study was undertaken to determine whether UCMs bioaccumulated by mussels in the field are also toxic. The feeding rate of mussels derived from polluted sites increased when they were placed in clean water, pointing to a loss of toxic agents from the tissues. At the end of the depuration period, water in which mussels from an oil-polluted site had been held contained a UCM. Steam-distillation extracts of the tissues of mussels taken from several polluted sites were shown to be highly toxic to the feeding activity of juvenile mussels. The tissues of mussels from these sites contained UCMs. Nontoxic steam distillates from clean mussels did not. Steam-distillation extracts of mussels from an oil-polluted site were fractionated by normal-phase high-performance liquid chromatography. A fraction, largely comprising a "monoaromatic" UCM, reduced the feeding rate of juvenile mussels by 70%. Two later-eluting fractions containing aromatic UCMs also produced smaller depressions in feeding rate. These results support our contention that some aromatic UCM hydrocarbons constitute a forgotten pollutant burden in the marine environment.

  5. Evaluation of Best Practices for the Euthanasia of Zebra Finches (Taeniopygia guttata)

    PubMed Central

    Scott, Kathleen E; Bracchi, Lauren A; Lieberman, Mia T; Hill, Nichola J; Caron, Tyler J; Patterson, Mary M

    2017-01-01

    Although zebra finches (Taeniopygia guttata) have been used in biomedical research for many years, no published reports are available about euthanizing these small birds. In this study, we compared 5 methods for zebra finch euthanasia: sodium pentobarbital (NaP) given intracoelomically with physical restraint but no anesthesia; isoflurane anesthesia followed by intracoelomic injection of NaP; and CO2 asphyxiation at 20%, 40%, and 80% chamber displacement rates (percentage of chamber volume per minute). Birds undergoing euthanasia were videorecorded and scored by 2 observers for behaviors potentially related to discomfort or distress. Time to recumbency and time until respiratory arrest (RA) were also assessed. RA was achieved faster by using NaP in a conscious bird compared to using isoflurane anesthesia followed by NaP; however, neither method caused behaviors that might affect animal welfare, such as open-mouth breathing, to any appreciable extent. Among the CO2 treatment groups, there was an inverse correlation between the chamber displacement rate used and the duration of open-mouth breathing, onset of head retroflexion, and time to RA. The results demonstrate that the intracoelomic administration of NaP in an awake, restrained zebra finch is a rapid and effective method of euthanasia. If CO2 is used to euthanize these birds, a high displacement rate (for example, 80%) will minimize the duration of the procedure and associated behaviors. PMID:29256376

  6. Evaluation of Best Practices for the Euthanasia of Zebra Finches (Taeniopygia guttata).

    PubMed

    Scott, Kathleen E; Bracchi, Lauren A; Lieberman, Mia T; Hill, Nichola J; Caron, Tyler J; Patterson, Mary M

    2017-11-01

    Although zebra finches (Taeniopygia guttata) have been used in biomedical research for many years, no published reports are available about euthanizing these small birds. In this study, we compared 5 methods for zebra finch euthanasia: sodium pentobarbital (NaP) given intracoelomically with physical restraint but no anesthesia; isoflurane anesthesia followed by intracoelomic injection of NaP; and CO2 asphyxiation at 20%, 40%, and 80% chamber displacement rates (percentage of chamber volume per minute). Birds undergoing euthanasia were videorecorded and scored by 2 observers for behaviors potentially related to discomfort or distress. Time to recumbency and time until respiratory arrest (RA) were also assessed. RA was achieved faster by using NaP in a conscious bird compared to using isoflurane anesthesia followed by NaP; however, neither method caused behaviors that might affect animal welfare, such as open-mouth breathing, to any appreciable extent. Among the CO2 treatment groups, there was an inverse correlation between the chamber displacement rate used and the duration of open-mouth breathing, onset of head retroflexion, and time to RA. The results demonstrate that the intracoelomic administration of NaP in an awake, restrained zebra finch is a rapid and effective method of euthanasia. If CO2 is used to euthanize these birds, a high displacement rate (for example, 80%) will minimize the duration of the procedure and associated behaviors.

  7. Public Education To Thwart Aquatic Nuisances.

    ERIC Educational Resources Information Center

    Cassell, Jodi L.

    1997-01-01

    Describes efforts to prevent the introduction and spread of nonindigenous species in U.S. waters, most notably the zebra mussel, a native of Russia, which has spread to 19 states and 2 Canadian provinces since its introduction to the Great Lakes in 1988. California Sea Grant Extension's boater education program augments federal and California laws…

  8. Assessment of dreissenid biodeposits as a potential food resource for invasive Asian carp

    USGS Publications Warehouse

    Anderson, Karl R.; Chapman, Duane C.; Hayer, Cari-Ann

    2016-01-01

    Silver carp (Hypophthalmichthys molitrix) and bighead carp (H. nobilis) are poised to invade the Laurentian Great Lakes. Zebra mussels (Dreissena polymorpha) and quagga mussels (D. rostriformis bugensis) have shifted nutrient pathways towards the benthos, partly through deposition of feces and rejected food particles called biodeposits. When biodeposit material was fed to bighead and silver carp, they fed on the material, but on average lost weight. Energy density between fed and unfed fish did not differ, but a few individual fish did gain weight on the biodeposits diet. Our results demonstrate that biodeposits might be considered a supplemental food for bigheaded carps.

  9. Changes in sex steroid hormone levels reflect the reproductive status of captive female zebra sharks (Stegostoma fasciatum).

    PubMed

    Nozu, Ryo; Murakumo, Kiyomi; Yano, Nagisa; Furuyama, Rina; Matsumoto, Rui; Yanagisawa, Makio; Sato, Keiichi

    2018-03-03

    Captive breeding in aquaria is a useful means for ex situ preservation of threatened elasmobranch species. To promote captive breeding, it is important to determine the female reproductive status. However, information regarding reproductive status in female elasmobranchs is limited. Here, we used zebra sharks, Stegostoma fasciatum, as a model for elasmobranch reproduction in captivity. We investigated the relationships among changes in the sex steroid hormone levels, follicle size, and egg-laying period to develop indicators for the female reproductive status. We confirmed that mature female zebra sharks undergo an annual reproductive cycle. Additionally, we showed that the variations in sex steroid hormone levels correlated with reproductive status in mature female zebra sharks. Plasma estradiol-17ß (E2) concentrations increased two months before ovarian follicle development and decreased along with follicle regression. Interestingly, E2 levels were inversely correlated with water temperature (R = -0.901). Moreover, high levels of testosterone (T) correlated well with the laying period. These results strongly suggest that E2 is an indicator for ovarian follicle development, and that T is a useful indicator for both the onset and end of the egg-laying period in captive zebra sharks. Copyright © 2018 Elsevier Inc. All rights reserved.

  10. Factors affecting 210Po and 210Pb activity concentrations in mussels and implications for environmental bio-monitoring programmes.

    PubMed

    Carvalho, Fernando P; Oliveira, João M; Alberto, G

    2011-02-01

    The activity of (210)Po and (210)Pb was determined in mussels of the same size (3.5-4.0 cm shell length) sampled monthly over a 17-month period at the Atlantic coast of Portugal. Average radionuclide concentration values in mussels were 759±277 Bq kg(-1) for (210)Po (range 460-1470 Bq kg(-1) dry weight), and 45±19 Bq kg(-1) for (210)Pb (range 23-96 Bq kg(-1) dry weight). Environmental parameters and mussel biometric parameters were monitored during the same period. Although there was no seasonal variation of radionuclide concentrations in sea water during the study period, the concentration of radionuclide activity in mussels varied seasonally displaying peaks of high concentrations in winter and low concentrations in summer. Analysis of radionuclide data in relation to the physiological Condition Index of mussels revealed that (210)Po and (210)Pb activities in the mussel (average activity per individual) remained nearly constant during the investigation period, while mussel body weight fluctuated due to fat storage/expenditure in the soft tissues. Similar variation of radionuclide concentrations was observed in mussels transplanted from the sea coast into the Tejo Estuary. However, under estuarine environmental conditions and with higher food availability throughout the year, transplanted mussel Condition Index was higher than in coastal mussels and average radionuclide concentrations were 210±75 Bq kg(-1) (dry weight) for (210)Po and 10±4 Bq kg(-1) (dry weight) for (210)Pb, therefore lower than in coastal mussels with similar shell length. It is concluded that the apparent seasonal fluctuation and inter-site difference of radionuclide concentrations were mostly caused by mussel body weight fluctuation and not by radionuclide body burden fluctuation. This interpretation can be extended to the apparent seasonal fluctuation in concentrations of lipophilic and lipophobic contaminants in mussels, and provides an explanation for occasional high concentrations of

  11. Mussels and sediment as monitoring tools for contaminants: which to use when?

    EPA Science Inventory

    For decades, sediments and mussels have been used to assess the ecological and human health risks associated with concentrations of bioavailable organic and metal contaminants in a variety of coastal-wide and localized monitoring programs. Mussels (Mytilus edulis) bioaccumulate o...

  12. A multi-biomarker approach in cross-transplanted mussels Mytilus galloprovincialis.

    PubMed

    Serafim, Angela; Lopes, Belisandra; Company, Rui; Cravo, Alexandra; Gomes, Tânia; Sousa, Vânia; Bebianno, Maria João

    2011-11-01

    The present work integrates the active biomonitoring (ABM) concept in mussels Mytilus galloprovincialis from the South coast of Portugal transplanted during 28 days between two sites with different sources of contamination, and vice versa, in order to assess biological effects in these mussels. For that purpose a multibiomarker approach was used. The suit of biomarkers indicative of metal contamination were metallothioneins (MT) and the enzyme δ-aminolevulinic acid dehydratase (ALAD), for organic contamination mixed function oxidase system (MFO), glutathione-S-transferase (GST) and acetylcholinesterase (AChE), as oxidative stress biomarkers superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GPx) and lipid peroxidation (LPO). These biomarkers were used to determine an index to evaluate the stress levels in these two sites. Site A is strongly influenced by metallic contamination, with higher Cu, Cr and Pb in M. galloprovincialis, as well as higher MT levels, antioxidant enzymes activities and LPO concentrations, and lower ALAD activity. In site B organic compounds (PAHs) are prevalent and native mussels show higher activities of the MFO system components and GST. Transplanted mussels had significant alterations in some biomarkers that reflect the type of contaminants present in each site, which demonstrates the primary role of the environment in determining the physiological characteristics of resident mussels. Therefore the application of ABM using a battery of biomarkers turns out to be a useful approach in sites where usually complex mixtures of contaminants occurs. In this study the biomarkers that better differentiate the impact of different contaminants at each site were MT, CYP450, SOD and CAT.

  13. Upper thermal tolerances of early life stages of freshwater mussels

    USGS Publications Warehouse

    Pandolfo, Tamara J.; Cope, W. Gregory; Arellano, Consuelo; Bringolf, Robert B.; Barnhart, M. Christopher; Hammer, E

    2010-01-01

    Freshwater mussels (order Unioniformes) fulfill an essential role in benthic aquatic communities, but also are among the most sensitive and rapidly declining faunal groups in North America. Rising water temperatures, caused by global climate change, industrial discharges, drought, or land development, could further challenge imperiled unionid communities. The aim of our study was to determine the upper thermal tolerances of the larval (glochidia) and juvenile life stages of freshwater mussels. Glochidia of 8 species of mussels were tested: Lampsilis siliquoidea, Potamilus alatus, Ligumia recta, Ellipsaria lineolata,Lasmigona complanata, Megalonaias nervosa, Alasmidonta varicosa, and Villosa delumbis. Seven of these species also were tested as juveniles. Survival trends were monitored while mussels held at 3 acclimation temperatures (17, 22, and 27°C) were exposed to a range of common and extreme water temperatures (20–42°C) in standard acute laboratory tests. The average median lethal temperature (LT50) among species in 24-h tests with glochidia was 31.6°C and ranged from 21.4 to 42.7°C. The mean LT50 in 96-h juvenile tests was 34.7°C and ranged from 32.5 to 38.8°C. Based on comparisons of LT50s, thermal tolerances differed among species for glochidia, but not for juveniles. Acclimation temperature did not affect thermal tolerance for either life stage. Our results indicate that freshwater mussels already might be living close to their upper thermal tolerances in some systems and, thus, might be at risk from rising environmental temperatures.

  14. Effect of the industrial canning on the toxicity of mussels contaminated with diarrhetic shellfish poisoning (DSP) toxins.

    PubMed

    Blanco, Juan; Arévalo, Fabiola; Correa, Jorge; Porro, M Corina; Cabado, Ana G; Vieites, Juan M; Moroño, Angeles

    2016-03-15

    The effect of canning in pickled sauce and autoclaving on weight, toxin content, toxin concentration and toxicity of steamed mussels was studied. Weight decreased by 25.5%. Okadaic acid (OA) and DTX2 content of mussel meat decreased by 24.1 and 42.5%, respectively. The estimated toxicity of the mussel remained nearly unchanged (increased by 2.9%). A part of the toxins lost by the mussels was leached to the sauce but the remaining part should have been thermally degraded. DTX2 underwent more degradation than OA and, in both toxins, free forms more than conjugated ones. This process, therefore, cannot be responsible for the large increments of toxicity of processed mussels -relative to the raw ones-sometimes detected by food processing companies. The final product could be monitored in several ways, but analysing the whole can content or the mussel meat once rehydrated seems to be the most equivalents to the raw mussel controls. Copyright © 2016 Elsevier Ltd. All rights reserved.

  15. Ammonium detection by formation of colored zebra-bands in a detecting tube.

    PubMed

    Hori, Tatsuaki; Niki, Keizou; Kiso, Yoshiaki; Oguchi, Tatsuo; Kamimoto, Yuki; Yamada, Toshiro; Nagai, Masahiro

    2010-06-15

    Ammonium ion was colorized by means of a diazo coupling reaction with 2-phenylphenol, where the color development reaction was conducted within 3min by using boric acid as a catalyst. The resulting colored solution (0.5ml) was supplied by suction to a detecting tube consisting of a nonwoven fabric test strip (2mm wide, 1mm thick, 150mm long) impregnated with benzylcetyldimethylammonium chloride in a stripe pattern and enclosed in a heat-shrinkable tube. When the colored solution was supplied to the detecting tube, blue zebra-bands formed, and the ammonium concentration was determined by counting the number of zebra-bands. The detection range was 1-20mg-Nl(-1). Ammonium ion in actual domestic wastewater samples was successfully detected by means of this method.

  16. Misidentification of sex for Lampsilis teres, Yellow Sandshell, and its implications for mussel conservation and wildlife management.

    PubMed

    Hess, Megan C; Inoue, Kentaro; Tsakiris, Eric T; Hart, Michael; Morton, Jennifer; Dudding, Jack; Robertson, Clinton R; Randklev, Charles R

    2018-01-01

    Correct identification of sex is an important component of wildlife management because changes in sex ratios can affect population viability. Identification of sex often relies on external morphology, which can be biased by intermediate or nondistinctive morphotypes and observer experience. For unionid mussels, research has demonstrated that species misidentification is common but less attention has been given to the reliability of sex identification. To evaluate whether this is an issue, we surveyed 117 researchers on their ability to correctly identify sex of Lampsilis teres (Yellow Sandshell), a wide ranging, sexually dimorphic species. Personal background information of each observer was analyzed to identify factors that may contribute to misidentification of sex. We found that median misidentification rates were ~20% across males and females and that observers falsely identified the number of female specimens more often (~23%) than males (~10%). Misidentification rates were partially explained by geographic region of prior mussel experience and where observers learned how to identify mussels, but there remained substantial variation among observers after controlling for these factors. We also used three morphometric methods (traditional, geometric, and Fourier) to investigate whether sex could be more correctly identified statistically and found that misidentification rates for the geometric and Fourier methods (which characterize shape) were less than 5% (on average 7% and 2% for females and males, respectively). Our results show that misidentification of sex is likely common for mussels if based solely on external morphology, which raises general questions, regardless of taxonomic group, about its reliability for conservation efforts.

  17. Ocean acidification and host-pathogen interactions: blue mussels, Mytilus edulis, encountering Vibrio tubiashii.

    PubMed

    Asplund, Maria E; Baden, Susanne P; Russ, Sarah; Ellis, Robert P; Gong, Ningping; Hernroth, Bodil E

    2014-04-01

    Ocean acidification (OA) can shift the ecological balance between interacting organisms. In this study, we have used a model system to illustrate the interaction between a calcifying host organism, the blue mussel Mytilus edulis and a common bivalve bacterial pathogen, Vibrio tubiashii, with organisms being exposed to a level of acidification projected to occur by the end of the 21st century. OA exposures of the mussels were carried out in relative long-term (4 months) and short-term (4 days) experiments. We found no effect of OA on the culturability of V. tubiashii, in broth or in seawater. OA inhibited mussel shell growth and impaired crystalline shell structures but did not appear to affect mussel immune parameters (i.e haemocyte counts and phagocytotic capacity). Despite no evident impact on host immunity or growth and virulence of the pathogen, V. tubiashii was clearly more successful in infecting mussels exposed to long-term OA compared to those maintained under ambient conditions. Moreover, OA exposed V. tubiashii increased their viability when exposed to haemocytes of OA-treated mussel. Our findings suggest that even though host organisms may have the capacity to cope with periods of OA, these conditions may alter the outcome of host-pathogen interactions, favouring the success of the latter. © 2013 Society for Applied Microbiology and John Wiley & Sons Ltd.

  18. Effects of oil and bioremediation on mussel (Mytilus edulis L.) growth in mudflats.

    PubMed

    Le Floch, S; Guyomarch, J; Merlin, F; Børseth, J F; Le Corre, P; Lee, K

    2003-10-01

    Mussels (Mytilus edulis L.) were exposed to crude oil during a field experiment to evaluate two bioremediation strategies (nutrient addition and nutrient addition with tilling). The mussels were placed in 4 mesocosms: Control, Oil, Oil + Nutrients, and Oil + Nutrients + Tilled. Tilling appeared to be clearly detrimental to mussel growth. Additionally, this field experiment demonstrated that at temperatures below 5 degrees C, growth was reduced to rates undetectable by the laser diffraction method. The data on mussel shell length show that this technique does offer very sensitive and useful comparative measurements of physiological function. Measurement of shell growth has the advantage over other techniques in that it is non-invasive and non-destructive and thus may be used continuously without disturbing critical physiological and biochemical functions; however, bivalve physiology is strongly linked to environmental conditions, so it is important to include such measures (i.e. seawater temperature and turbidity) in the design of the biomonitoring program. Elevated polycyclic aromatic hydrocarbon (PAH) levels reflected bioaccumulation in mussels from all the oiled mesocosms. This correlated with reduction in growth rate. Maximum reduction in growth was observed in mussels from the tilled mesocosm which contained the lowest phenanthrene and dibenzothiophene concentrations. The tilling caused an increase in suspended solids which inhibited filter feeding activity, and resulted in suppressed growth and slower intake of PAH-laden sediment.

  19. Non-lethal assessment of freshwater mussel physiological response to changes in environmental factors

    USGS Publications Warehouse

    Fritts, Andrea K.; Peterson, James T.; Wisniewski, Jason M.; Bringolf, Robert B.

    2015-01-01

    The development of effective nonlethal biomonitoring techniques is imperative for the preservation of imperiled freshwater mussel populations. Changes in hemolymph chemistry profiles and tissue glycogen are potential biomarkers for nonlethally monitoring stress in mussels. We sampled three species in the Flint River Basin over 2 years to evaluate how these hemolymph and tissue biomarkers responded to environmental changes. We used hierarchical linear models to evaluate the relationships between variation in the biomarkers and environmental factors and found that the responses of the hemolymph and tissue parameters were strongly related to stream discharge. Shifts in alanine aminotransferase and glycogen showed the largest relations with discharge at the time of sampling, while magnesium levels were most explained by the discharge for 5 days prior to sampling. Aspartate aminotransferase, bicarbonate, and calcium showed the strongest relations with mean discharge for 15 days prior to sampling. The modeling results indicated that biomarker responses varied substantially among individuals of different size, sex, and species and illustrated the value of hierarchical modeling techniques to account for the inherent complexity of aquatic ecosystems.

  20. Effects of high salinity wastewater discharges on unionid mussels in the Allegheny River, Pennsylvania

    USGS Publications Warehouse

    Kathleen Patnode,; Hittle, Elizabeth A.; Robert Anderson,; Lora Zimmerman,; Fulton, John W.

    2015-01-01

    We examined the effect of high salinity wastewater (brine) from oil and natural gas drilling on freshwater mussels in the Allegheny River, Pennsylvania, during 2012. Mussel cages (N = 5 per site) were deployed at two sites upstream and four sites downstream of a brine treatment facility on the Allegheny River. Each cage contained 20 juvenile northern riffleshell mussels Epioblasma torulosa rangiana). Continuous specific conductance and temperature data were recorded by water quality probes deployed at each site. To measure the amount of mixing throughout the entire study area, specific conductance surveys were completed two times during low-flow conditions along transects from bank to bank that targeted upstream (reference) reaches, a municipal wastewater treatment plant discharge upstream of the brine-facility discharge, the brine facility, and downstream reaches. Specific conductance data indicated that high specific conductance water from the brine facility (4,000–12,000 µS/cm; mean 7,846) compared to the reference reach (103–188 µS/cm; mean 151) is carried along the left descending bank of the river and that dilution of the discharge via mixing does not occur until 0.5 mi (805 m) downstream. Juvenile northern riffleshell mussel survival was severely impaired within the high specific conductance zone (2 and 34% at and downstream of the brine facility, respectively) and at the municipal wastewater treatment plant (21%) compared to background (84%). We surveyed native mussels (family Unionidae) at 10 transects: 3 upstream, 3 within, and 4 downstream of the high specific conductance zone. Unionid mussel abundance and diversity were lower for all transects within and downstream of the high conductivity zone compared to upstream. The results of this study clearly demonstrate in situ toxicity to juvenile northern riffleshell mussels, a federally endangered species, and to the native unionid mussel assemblage located downstream of a brine discharge to the

  1. Factors Affecting Technology Uses in Schools: An Ecological Perspective

    ERIC Educational Resources Information Center

    Zhao, Yong; Frank, Kenneth A.

    2003-01-01

    Why is technology not used more in schools? Many researchers have tried to solve this persistent puzzle. The authors of this article report on their study of technology uses in 19 schools. They suggest an ecological metaphor, using the example of the introduction of the zebra mussel into the Great Lakes, to integrate and organize sets of factors…

  2. Mutations of amino acids in the DNA-recognition domain of Epstein-Barr virus ZEBRA protein alter its sub-nuclear localization and affect formation of replication compartments

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Park, Richard; Heston, Lee; Shedd, Duane

    ZEBRA, a transcription factor and DNA replication protein encoded by the Epstein-Barr virus (EBV) BZLF1 gene, plays indispensable roles in the EBV lytic cycle. We recently described the phenotypes of 46 single amino acid substitutions introduced into the DNA-recognition region of ZEBRA [Heston, L., El-Guindy, A., Countryman, J., Dela Cruz, C., Delecluse, H.J., and Miller, G. 2006]. The 27 DNA-binding-proficient mutants exhibited distinct defects in their ability to activate expression of the kinetic classes of viral genes. Four phenotypic variants could be discerned: wild-type, defective at activating Rta, defective at activating early genes, and defective at activating late genes. Heremore » we analyze the distribution of ZEBRA within the nucleus and the localization of EA-D (the viral DNA polymerase processivity factor), an indicator of the development of replication compartments, in representatives of each phenotypic group. Plasmids encoding wild-type (WT) and mutant ZEBRA were transfected into 293 cells containing EBV-bacmids. WT ZEBRA protein was diffusely and smoothly distributed throughout the nucleus, sparing nucleoli, and partially recruited to globular replication compartments. EA-D induced by WT ZEBRA was present diffusely in some cells and concentrated in globular replication compartments in other cells. The distribution of ZEBRA and EA-D proteins was identical to WT following transfection of K188R, a mutant with a conservative change. The distribution of S186A mutant ZEBRA protein, defective for activation of Rta and EA-D, was identical to WT, except that the mutant ZEBRA was never found in globular compartments. Co-expression of Rta with S186A mutant rescued diffuse EA-D but not globular replication compartments. The most striking observation was that several mutant ZEBRA proteins defective in activating EA-D (R179A, K181A and A185V) and defective in activating lytic viral DNA replication and late genes (Y180E and K188A) were localized to numerous

  3. Mussel byssus attachment weakened by ocean acidification

    NASA Astrophysics Data System (ADS)

    O'Donnell, Michael J.; George, Matthew N.; Carrington, Emily

    2013-06-01

    Biomaterials connect organisms to their environments. Their function depends on biological, chemical and environmental factors, both at the time of creation and throughout the life of the material. Shifts in the chemistry of the oceans driven by anthropogenic CO2 (termed ocean acidification) have profound implications for the function of critical materials formed under these altered conditions. Most ocean acidification studies have focused on one biomaterial (secreted calcium carbonate), frequently using a single assay (net rate of calcification) to quantify whether reductions in environmental pH alter how organisms create biomaterials. Here, we examine biological structures critical for the success of ecologically and economically important bivalve molluscs. One non-calcified material, the proteinaceous byssal threads that anchor mytilid mussels to hard substrates, exhibited reduced mechanical performance when secreted under elevated pCO2 conditions, whereas shell and tissue growth were unaffected. Threads made under high pCO2 (>1,200μatm) were weaker and less extensible owing to compromised attachment to the substratum. According to a mathematical model, this reduced byssal fibre performance, decreasing individual tenacity by 40%. In the face of ocean acidification, weakened attachment presents a potential challenge for suspension-culture mussel farms and for intertidal communities anchored by mussel beds.

  4. A Mussel-Derived One-Component Adhesive Coacervate

    PubMed Central

    Wei, Wei; Tan, Yerpeng; Rodriguez, N. Martinez; Yu, Jing; Israelachvili, Jacob N.; Waite, J. Herbert

    2013-01-01

    Marine organisms process and deliver many of their underwater coatings and adhesives as complex fluids. In marine mussels, one such fluid, secreted during the formation of adhesive plaques, consists of a concentrated colloidal suspension of a mussel foot protein (mfp) known as Mfp-3S. Results of this study suggest that Mfp-3S becomes a complex fluid by a liquid-liquid phase separation from equilibrium solution at a pH and ionic strength reminiscent of conditions created by the mussel foot during plaque formation. The pH dependence of phase separation and its sensitivity indicate that inter/intra-molecular electrostatic interactions are partially responsible for driving the phase separation. Hydrophobic interactions between the nonpolar Mfp-3S proteins provide another important driving force for coacervation. As complex coacervation typically results from charge-charge interactions between polyanions and polycations, Mfp-3S is thus unique in being the only known protein that coacervates with itself. The Mfp-3S coacervate was shown to have an effective interfacial energy of ≤ 1 mJ/m2 which explains its tendency to spread over or engulf most surfaces. Of particular interest to biomedical applications is the extremely high adsorption capacity of coacervated Mfp-3S on hydroxyapatite. PMID:24060881

  5. Digestive physiology comparisons of aquatic invertebrates in the Upper Mississippi River Basin

    USGS Publications Warehouse

    Sauey, Blake W.; Amberg, Jon J.; Cooper, Scott T.; Grunwald, Sandra K.; Haro, Roger J.; Gaikowski, Mark

    2016-01-01

    Limited information is available on the composition of digestive enzymes present in unionid mussels and the zebra mussel, Dreissena polymorpha. Available information is nearly exclusive to species used for culture purposes. A commercially available enzyme assay kit was used to examine the effect of habitat within an ecosystem, season, and species on the activities of several digestive enzymes. We used Amblema plicata to represent native unionids, D. polymorpha, and also Hydropsyche orris as an outgroup to compare differences between mussels and other macroinvertebrates. The data indicated that neither location nor time affect the activities of the digestive enzymes tested; species was the only factor to affect the activity. Differences were found mostly between four enzymes: naphthol-AS-BI-phosphohydrolase, acid phosphatase, alkaline phosphatase, and β-galactosidase.

  6. Status of the Mussel Resource in Little South Fork Cumberland River

    Treesearch

    Melvin L. Warren; Wendell R. Haag; Brooks M. Burr

    1999-01-01

    As recently as the 198Os, the Little South Fork Cumberland River of southeastern Kentucky supported a diverse freshwater mussel fauna (Starnes and Bogan 1982; Appendix A). The Little South Fork represented one of the last rivers to support a high number of mussel species in the Cumberland River drainage of Kentucky and Tennessee. The river was first surveyed...

  7. Insights into the innate immunity of the Mediterranean mussel Mytilus galloprovincialis

    PubMed Central

    2011-01-01

    Background Sessile bivalves of the genus Mytilus are suspension feeders relatively tolerant to a wide range of environmental changes, used as sentinels in ecotoxicological investigations and marketed worldwide as seafood. Mortality events caused by infective agents and parasites apparently occur less in mussels than in other bivalves but the molecular basis of such evidence is unknown. The arrangement of Mytibase, interactive catalogue of 7,112 transcripts of M. galloprovincialis, offered us the opportunity to look for gene sequences relevant to the host defences, in particular the innate immunity related genes. Results We have explored and described the Mytibase sequence clusters and singletons having a putative role in recognition, intracellular signalling, and neutralization of potential pathogens in M. galloprovincialis. Automatically assisted searches of protein signatures and manually cured sequence analysis confirmed the molecular diversity of recognition/effector molecules such as the antimicrobial peptides and many carbohydrate binding proteins. Molecular motifs identifying complement C1q, C-type lectins and fibrinogen-like transcripts emerged as the most abundant in the Mytibase collection whereas, conversely, sequence motifs denoting the regulatory cytokine MIF and cytokine-related transcripts represent singular and unexpected findings. Using a cross-search strategy, 1,820 putatively immune-related sequences were selected to design oligonucleotide probes and define a species-specific Immunochip (DNA microarray). The Immunochip performance was tested with hemolymph RNAs from mussels injected with Vibrio splendidus at 3 and 48 hours post-treatment. A total of 143 and 262 differentially expressed genes exemplify the early and late hemocyte response of the Vibrio-challenged mussels, respectively, with AMP trends confirmed by qPCR and clear modulation of interrelated signalling pathways. Conclusions The Mytibase collection is rich in gene transcripts

  8. Shell carbon isotope indicators of metabolic activity in the deep-sea mussel Bathymodiolus childressi

    NASA Astrophysics Data System (ADS)

    Riekenberg, P. M.; Carney, R. S.; Fry, B.

    2018-04-01

    The incorporation of metabolic carbon (Cm) into shells of mollusks has been used as an indicator of animal condition and availability of food resources in estuarine and freshwater settings. This study examines Cm in Bathymodiolus childressi, a marine cold seep mussel dependent on methanotrophic symbionts. As seeps develop, mature, and go quiescent, methane supply will vary and affect the amount of metabolic carbon deposited into the growing shell. B. childressi (n = 136) were live-collected from two seep sites over a 17 year period in the Northern Gulf of Mexico to investigate whether changes in Cm were detectable between sites and across years. Significant differences in Cm were observed between mussel populations at Brine Pool (15.4 ± 0.4%) and Bush Hill (10.3 ± 0.3%). Cm also changed significantly within each site across year (Bush Hill 1991: 12.2 ± 0.5%, 1992: 17.3 ± 0.8%) and decadal time scales (Brine Pool 1989: 15.5 ± 0.7%, 2006: 19.5 ± 0.7%). These findings agree with previous studies that found mussel condition was higher at Brine Pool and correlate well with a trophic mixing model that indicated significantly higher methane source utilization at the Brine Pool (65 ± 1.1%) than at Bush Hill (49 ± 1.6%). Further development of this method should allow for assessment of Cm in shell assemblages as an indicator of historical resource availability at both active and former cold seep sites.

  9. No evidence for host specialization or host-race formation in the European bitterling (Rhodeus amarus), a fish that parasitizes freshwater mussels.

    PubMed

    Reichard, M; Bryja, J; Polačik, M; Smith, C

    2011-09-01

    Coevolutionary relationships between parasites and hosts can elevate the rate of evolutionary changes owing to reciprocal adaptations between coevolving partners. Such relationships can result in the evolution of host specificity. Recent methodological advances have permitted the recognition of cryptic lineages, with important consequences for our understanding of biological diversity. We used the European bitterling (Rhodeus amarus), a freshwater fish that parasitizes unionid mussels, to investigate host specialization across regions of recent and ancient sympatry between coevolving partners. We combined genetic data (12 microsatellite and 2 mitochondrial markers) from five populations with experimental data for possible mechanisms of host species recognition (imprinting and conditioning). We found no strong evidence for the existence of cryptic lineages in R. amarus, though a small proportion of variation among individuals in an area of recent bitterling-mussel association was statistically significant in explaining host specificity. No other measures supported the existence of host-specific lineages. Behavioural data revealed a weak effect of conditioning that biased behavioural preferences towards specific host species. Host imprinting had no effect on oviposition behaviour. Overall, we established that populations of R. amarus show limited potential for specialization, manifested as weak effects of host conditioning and genetic within-population structure. Rhodeus amarus is the only species of mussel-parasitizing fish in Europe, which contrasts with the species-rich communities of bitterling in eastern Asia where several host-specific bitterling occur. We discuss costs and constraints on the evolution of host-specific lineages in our study system and more generally. © 2011 Blackwell Publishing Ltd.

  10. USING MUSSEL ISOTOPE RATIOS TO ASSESS ANTHROPOGEN NITROGEN INPUTS TO COASTAL ECOSYSTEMS

    EPA Science Inventory

    The stable nitrogen isotope ratio in ribbed mussel (Geukensia demissus) tissue was investigated as an indicator of the source of nitrogen inputs to coastal salt marshes. Mussels fed a diet of 15N enriched algae in the laboratory showed an increase in tissue nitrogen isotope rati...

  11. Deeply hidden inside introduced biogenic structures - Pacific oyster reefs reduce detrimental barnacle overgrowth on native blue mussels

    NASA Astrophysics Data System (ADS)

    Buschbaum, Christian; Cornelius, Annika; Goedknegt, M. Anouk

    2016-11-01

    In sedimentary coastal ecosystems shells of epibenthic organisms such as blue mussels (Mytilus edulis) provide the only major attachment surface for barnacle epibionts, which may cause detrimental effects on their mussel basibionts by e.g. reducing growth rate. In the European Wadden Sea, beds of native blue mussels have been invaded by Pacific oysters Crassostrea gigas, which transformed these beds into mixed reefs of oysters with mussels. In this study, we determined the spatial distribution of M. edulis and their barnacle epibionts (Semibalanus balanoides) within the reef matrix. Mean mussel density near the bottom was about twice as high compared to the mussel density near the top of an oyster reef, whereas barnacles on mussels showed a reversed pattern. Barnacle dry weight per mussel was on average 14 times higher near the top than at the bottom. This pattern was confirmed by experimentally placing clean M. edulis at the top and on the bottom of oyster reefs at two sites in the Wadden Sea (island of Texel, The Netherlands; island of Sylt, Germany). After an experimental period of five weeks (April and May 2015, the main settlement period of S. balanoides), the number of barnacles per mussel was at both sites significantly higher on mussels near the top compared to near the bottom. We conclude that the oyster reef matrix offers a refuge for M. edulis: inside reefs they are not only better protected against predators but also against detrimental barnacle overgrowth. This study shows that alien species can cause beneficial effects for native organisms and should not be generally considered as a risk for the recipient marine ecosystems.

  12. Freshwater mussel survey for the Columbia Dam removal, Paulins Kill, New Jersey

    USGS Publications Warehouse

    Galbraith, Heather S.; Blakeslee, Carrie J.; Cole, Jeffrey C.; Silldorff, Erik L.

    2018-06-04

    Semi-quantitative mussel surveys, conducted by the U.S. Geological Survey and the Delaware Riverkeeper Network in cooperation with The Nature Conservancy, were completed in the vicinity of the Columbia Dam, on the Paulins Kill, New Jersey, in August 2017 in order to document the mussel species composition and relative abundance prior to removal of the dam. Surveys were conducted from the Brugler Road Bridge downriver approximately 2,000 meters (m) to the Columbia Dam and downriver from the dam about 300 m to 75 m upriver from the confluence of the Paulins Kill with the Delaware River. Sixteen sections (average length=175 m) were surveyed by personnel snorkeling or SCUBA diving; 13 sections were upriver from the dam, and 3 were downriver from the dam. Mussels, as they were encountered by surveyors, were removed from the sediment, immediately identified to species, and replaced in their original collection locations. Habitat data were collected for each surveyed section. Upriver and downriver from the dam, river margins with dense vegetation were examined for mussels by personnel using snorkels in transects (approximately 25 meters) perpendicular to river flow every 50 m on both sides of the river. Only two species were found upriver from the dam, and those were present in relatively low numbers. Catch per unit effort is reported here within parentheses as the average across upriver sections in number of mussels per person hour of survey time: 42 Elliptio complanata (2.6) and 1 Pyganodon cataracta (0.1) were found upriver from the dam. No mussels were found in the dense vegetation either upriver or downriver of the dam by surveyors using snorkels. Significantly higher species richness and mussel catch per unit effort were found downriver from the dam than upriver, including 106 E. complanta (32.5), 27 Utterbackiana implicata (8.2), 1 Alasmidonta undulata (0.4), 2 Lampsilis cariosa (0.5), 6 Lampsilis radiata (2.1), 4 P. cataracta (1.1), and 1 Strophitus undulatus (0

  13. Effects of turbidity, sediment, and polyacrylamide on native freshwater mussels

    USGS Publications Warehouse

    Buczek, Sean B.; Cope, W. Gregory; McLaughlin, Richard A.; Kwak, Thomas J.

    2018-01-01

    Turbidity is a ubiquitous pollutant adversely affecting water quality and aquatic life in waterways globally. Anionic polyacrylamide (PAM) is widely used as an effective chemical flocculent to reduce suspended sediment (SS) and turbidity. However, no information exists on the toxicity of PAM‐flocculated sediments to imperiled, but ecologically important, freshwater mussels (Unionidae). Thus, we conducted acute (96 h) and chronic (24 day) laboratory tests with juvenile fatmucket (Lampsilis siliquoidea) and three exposure conditions (nonflocculated settled sediment, SS, and PAM‐flocculated settled sediment) over a range of turbidity levels (50, 250, 1,250, and 3,500 nephelometric turbidity units). Survival and sublethal endpoints of protein oxidation, adenosine triphosphate (ATP) production, and protein concentration were used as measures of toxicity. We found no effect of turbidity levels or exposure condition on mussel survival in acute or chronic tests. However, we found significant reductions in protein concentration, ATP production, and oxidized proteins in mussels acutely exposed to the SS condition, which required water movement to maintain sediment in suspension, indicating responses that are symptoms of physiological stress. Our results suggest anionic PAM applied to reduce SS may minimize adverse effects of short‐term turbidity exposure on juvenile freshwater mussels without eliciting additional lethal or sublethal toxicity.

  14. Amyloidosis in a Captive Zebra Finch (Taeniopygia guttata) Research Colony

    PubMed Central

    Shientag, Lisa J; Garlick, David S; Galati, Erin

    2016-01-01

    Five birds in a captive zebra finch research colony were diagnosed with systemic amyloidosis within a 7-mo period by means of postmortem Congo red staining and green birefringence under polarized light. The liver was the most frequently and usually the most seriously affected organ, followed by the spleen and then the kidney. All 5 birds had been clinically affected with various inflammatory, infectious, and neoplastic conditions associated with amyloid A (AA) amyloidosis in humans and animals. Immunohistochemistry using antisera against duck AA protein revealed that tissues from 2 of the 5 birds were positive for the presence of AA protein and systemic inflammation-associated amyloidosis. Although the development of AA amyloidosis has been associated with chronic inflammation, trauma, and various infectious and neoplastic diseases as well as possible genetic predispositions and stresses linked to overcrowding, the root causes for individual cases of AA amyloidosis are incompletely understood. As far as we know, this report is the first description of AA amyloidosis in captive, research zebra finches. PMID:27298248

  15. Relationship between oxygen concentration, respiration and filtration rate in blue mussel Mytilus edulis

    NASA Astrophysics Data System (ADS)

    Tang, Baojun; Riisgård, Hans Ulrik

    2018-03-01

    The large water-pumping and particle-capturing gills of the filter-feeding blue mussel Mytilus edulis are oversized for respiratory purposes. Consequently, the oxygen uptake rate of the mussel has been suggested to be rather insensitive to decreasing oxygen concentrations in the ambient water, since the diffusion rate of oxygen from water flowing through the mussel determines oxygen uptake. We tested this hypothesis by measuring the oxygen uptake in mussels exposed to various oxygen concentrations. These concentrations were established via N2-bubbling of the water in a respiration chamber with mussels fed algal cells to stimulate fully opening of the valves. It was found that mussels exposed to oxygen concentrations decreasing from 9 to 2 mg O2/L resulted in a slow but significant reduction in the respiration rate, while the filtration rate remained high and constant. Thus, a decrease of oxygen concentration by 78% only resulted in a 25% decrease in respiration rate. However, at oxygen concentrations below 2 mg O2/L M. edulis responded by gradually closing its valves, resulting in a rapid decrease of filtration rate, concurrent with a rapid reduction of respiration rate. These observations indicated that M. edulis is no longer able to maintain its normal aerobic metabolism at oxygen concentration below 2 mg O2/L, and there seems to be an energy-saving mechanism in bivalve molluscs to strongly reduce their activity when exposed to low oxygen conditions.

  16. Evaluation of methods for attaching PIT tags and biotelemetry devices to freshwater mussels

    USGS Publications Warehouse

    Young, S.P.; Isely, J.J.

    2008-01-01

    We evaluated methods to attach PIT tags and transmitters to freshwater mussels. Mussels received externally-mounted PIT tags using cyanoacrylate or underwater epoxy, and a sub-group of those with PIT tags attached using cyanoacrylate also received dummy transmitters. Tag retention and survival were 100% after a 30 day laboratory observation period for each method. During the subsequent 18 months of field observation, underwater epoxy and cyanoacrylate proved to be adequate adhesives for attaching PIT tags and transmitters. Epoxy performed best with 100% PIT tag retention. Cyanoacrylate also provided high retention rates of PIT tags and transmitters, >90%. Mortality was minimal at 4.7% for all relocated mussels over 18 months. All mortalities were those tagged with cyanoacrylate. Three of the mortalities occurred among mussels fitted with dummy transmitters, and seven among PIT tags only. Percent recapture of the different tag/adhesive combinations ranged from 48 - 77.5% during 6- and 18-month surveys. Results suggest both adhesives provide a reliable method for external attachment of tags during freshwater mussel research; however, epoxy may be better suited because of slightly higher tag retention and reduced emersion times during attachment. Copyright ?? 2008 Malacological Society of Australasia.

  17. Polycyclic aromatic hydrocarbons in sediments and mussels of Corral Bay, south central Chile.

    PubMed

    Palma-Fleming, Hernan; P, Adalberto J Asencio; Gutierrez, Elena

    2004-03-01

    PAHs were measured in sediments and mussels (Mytilus chilensis) from Carboneros and Puerto Claro, located in Corral Bay, Valdivia. According to the ratio of phenanthrene/anthracene and fluoranthene/pyrene concentrations, these sites are medium polluted with PAHs originating mainly from pyrolytic sources. Fluoranthene was the major component measured in mussels (3.1-390 ng g(-1) dry weight) and sediments (6.9-74.1 ng g(-1) dry weight). In general, mussels were mainly exposed to the dissolved fraction of the lower molecular weight PAHs (tri- and tetra-aromatics) while the higher molecular ring systems (penta- and hexa-aromatics) were more bioavailable to sediments. Mussel PAHs content was relatively constant, with the exception of the 1999 summer season (March), when higher concentration values were found in both sites; however, PAHs residues in sediments showed a temporal variation.

  18. Acute toxicity of six freshwater mussel species (Glochidia) to six chemicals: Implications for daphnids and Utterbackia imbecillis as surrogates for protection of freshwater mussels (Unionidae)

    USGS Publications Warehouse

    Milam, C.D.; Farris, J.L.; Dwyer, F.J.; Hardesty, D.K.

    2005-01-01

    Acute (24-h) toxicity tests were used in this study to compare lethality responses in early life stages (glochidia) of six freshwater mussel species, Leptodea fragilis, U. imbecillis, Lampsilis cardium, Lampsilis siliquoidea, Megalonaias nervosa, and Ligumia subrostrata, and two standard test organisms, Ceriodaphnia dubia and Daphnia magna. Concentrations of carbaryl, copper, 4-nonylphenol, pentachlorophenol, permethrin, and 2,4-D were used in acute exposures to represent different chemical classes and modes of action. The relative sensitivities of species were evaluated by ranking their LC 50 values for each chemical. We used these ranks to determine the extent to which U. imbecillis (one of the most commonly used unionids in toxicity tests) was representative of the tolerances of other mussels. We also calculated geometric mean LC50s for the families Unionidae and Daphnidae. Rankings of these data were used to assess the extent to which Daphnidae can be used as surrogates for freshwater mussels relative to chemical sensitivity. While no single chemical elicited consistently high or low toxicity estimates, carbaryl and 2,4-D were generally the least toxic to all species tested. No species was always the most sensitive, and Daphnidae were generally protective of Unionidae. Utterbackia imbecillis, while often proposed as a standard unionid mussel test species, did not always qualify as a sufficient surrogate (i.e., a substitute organism that often elicits similar sensitivity responses to the same contaminant exposure) for other species of mussels, since it was usually one of the more tolerant species in our rankings. U. imbecillis should be used as a surrogate species only with this caution on its relative insensitivity. ?? 2005 Springer Science+Business Media, Inc.

  19. Environmental Impact Research Program. An Instruction Report on Freshwater Mussels.

    DTIC Science & Technology

    1983-09-01

    34Greater Adaptability of Fresh-Water Mussels to Natural Rather Than to Artificial Displacement," The Nautilus Vol 86, pp 76-79. Isom, B. G. 1980...cotizing and Anaesthetizing Gastropods ," Malacologia 2: 231-238. van der Schalie, H. 1953. "Nembutal as a Relaxing Agent for Mollusks," The American...of Philadelphia, Philadelphia, Pa. Imlay, M. J. 1972. "Greater Adaptability of Freshwater Mussels to Natural Rather Than to Artificial Displacement

  20. Biomonitoring of Trace Metals in the Keban Dam Reservoir (Turkey) Using Mussels (Unio elongatulus eucirrus) and Crayfish (Astacus leptodactylus).

    PubMed

    Varol, Memet; Sünbül, Muhammet Raşit

    2018-01-03

    Freshwater mussels and crayfish are commonly used as biomonitors of trace metals. In the present study, the concentrations of ten metals were determined in mussels (Unio elongatulus eucirrus) and crayfish (Astacus leptodactylus) collected from the Keban Dam Reservoir in Turkey. The significant spatial differences in concentrations of studied metals except As in mussels were not found. However, Co, Cr, Cu, and Zn concentrations in mussels and As, Co, Cu, Fe, Pb, and Zn concentrations in crayfish showed significant seasonal differences. As, Cd, and Mn levels in mussels were about nine times higher than those in crayfish. The concentrations of Cd, Cr, Cu, Pb, Zn, and inorganic As in crayfish and mussels were lower than maximum permissible levels. When compared with other biomonitoring studies using mussels and crayfish, high concentrations of As, Cd, Co, Cr, and Ni in mussels and Cr and Ni in crayfish were observed due to lithogenic sources and anthropogenic activities in the basin. Bioconcentration factor values of Fe, Mn, Cd, and Zn in mussels and Zn, Cu, Fe, and Co in crayfish were > 1000, which indicates that both U. e. eucirrus and A. leptodactylus have potential to bioaccumulate these metals. Therefore, attention should be paid to mussels and crayfish from ecological and human health perspective, because they are potential vectors of metals to higher trophic levels.

  1. CONDITIONS FOR COEXISTENCE OF FRESHWATER MUSSEL SPECIES VIA PARTITIONING OF FISH HOST RESOURCES

    EPA Science Inventory

    Riverine freshwater mussel species can be found in highly diverse communities where many similar species coexist. Mussel species potentially compete for food and space as adults, and for fish host resources during the larval (glochidial) stage. Resource partitioning at the larv...

  2. An evaluation of freshwater mussel toxicity data in the derivation of water quality guidance and standards for copper

    USGS Publications Warehouse

    March, F.A.; Dwyer, F.J.; Augspurger, T.; Ingersoll, C.G.; Wang, N.; Mebane, C.A.

    2007-01-01

    The state of Oklahoma has designated several areas as freshwater mussel sanctuaries in an attempt to provide freshwater mussel species a degree of protection and to facilitate their reproduction. We evaluated the protection afforded freshwater mussels by the U.S. Environmental Protection Agency (U.S. EPA) hardness-based 1996 ambient copper water quality criteria, the 2007 U.S. EPA water quality criteria based on the biotic ligand model and the 2005 state of Oklahoma copper water quality standards. Both the criterion maximum concentration and criterion continuous concentration were evaluated. Published acute and chronic copper toxicity data that met American Society for Testing and Materials guidance for test acceptability were obtained for exposures conducted with glochidia or juvenile freshwater mussels. We tabulated toxicity data for glochidia and juveniles to calculate 20 species mean acute values for freshwater mussels. Generally, freshwater mussel species mean acute values were similar to those of the more sensitive species included in the U.S. EPA water quality derivation database. When added to the database of genus mean acute values used in deriving 1996 copper water quality criteria, 14 freshwater mussel genus mean acute values included 10 of the lowest 15 genus mean acute values, with three mussel species having the lowest values. Chronic exposure and sublethal effects freshwater mussel data available for four species and acute to chronic ratios were used to evaluate the criterion continuous concentration. On the basis of the freshwater mussel toxicity data used in this assessment, the hardness-based 1996 U.S. EPA water quality criteria, the 2005 Oklahoma water quality standards, and the 2007 U.S. EPA water quality criteria based on the biotic ligand model might need to be revised to afford protection to freshwater mussels. ?? 2007 SETAC.

  3. Three new mussel tissue standard reference materials (SRMs) for the determination of organic contaminants.

    PubMed

    Poster, Dianne L; Schantz, Michele M; Kucklick, John R; Lopez de Alda, Maria J; Porter, Barbara J; Pugh, Rebecca; Wise, Stephen A

    2004-03-01

    Three new mussel tissue standard reference materials (SRMs) have been developed by the National Institute of Standards and Technology (NIST) for the determination of the concentrations of organic contaminants. The most recently prepared material, SRM 1974b, is a fresh frozen tissue homogenate prepared from mussels ( Mytilus edulis) collected in Boston Harbor, Massachusetts. The other two materials, SRMs 2977 and 2978, are freeze-dried tissue homogenates prepared from mussels collected in Guanabara Bay, Brazil and Raritan Bay, New Jersey, respectively. All three new mussel tissue SRMs complement the current suite of marine natural-matrix SRMs available from NIST that are characterized for a wide range of contaminants (organic and inorganic). SRM 1974b has been developed to replace its predecessor SRM 1974a, Organics in Mussel Tissue, for which the supply is depleted. Similarly, SRMs 2977 and 2978 were developed to replace a previously available (supply depleted) freeze-dried version of SRM 1974a, SRM 2974, Organics in Freeze-Dried Mussel Tissue. SRM 1974b is the third in a series of fresh frozen mussel tissue homogenate SRMs prepared from mussels collected in Boston Harbor starting in 1988. SRM 1974b has certified concentration values for 22 polycyclic aromatic hydrocarbons (PAHs), 31 polychlorinated biphenyl congeners (PCBs), and 7 chlorinated pesticides. Reference values are provided for additional constituents: 16 PAHs, 8 PCBs plus total PCBs, 6 pesticides, total extractable organics, methylmercury, and 11 trace elements. PAH concentrations range from about 2 ng g(-1 )dry mass (cyclopenta[ cd]pyrene) to 180 ng g(-1 )dry mass (pyrene). PCB concentrations range from about 2 ng g(-1 )dry mass (PCB 157) to 120 ng g(-1 )dry mass (PCB 153). The reference value for total PCBs in SRM 1974b is (2020 +/- 420) ng g(-1 )dry mass. Pesticide concentrations range from about 4 ng g(-1 )dry mass (4,4'-DDT) to 40 ng g(-1 )dry mass (4,4'-DDE). SRM 2977 has certified values for 14

  4. Advances and opportunities in assessing contaminant sensitivity of freshwater mussel (unionidae) early life stages

    USGS Publications Warehouse

    Augspurger, T; Dwyer, F.J.; Ingersoll, C.G.; Kane, C.M.

    2007-01-01

    Freshwater mussels (family Unionidae, also referred to as freshwater pearly mussels, unionids, or naiades) are one of North America’s most endangered faunal groups. Near unanimity exists in characterizations of the imperilment of these ecologically, economically, and culturally important bivalve mollusks. Freshwater mussels are a renewable resource supporting a shell industry in the United States valued at $40–50 million annually [1]. In addition to being a food source for aquatic and terrestrial vertebrates, this diverse fauna helps stabilize sediment [2] and provides critical nutrient and energy cycling in streams and lakes by filtering phytoplankton, bacteria, and particulate organic matter from the water column [3]. Thirty-five species of freshwater mussels are extinct [4], 70 species are listed as threatened or endangered under the U.S. Endangered Species Act (www.fws.gov/endangered/wildlife.html), and nearly 180 species are identified as critically imperiled or vulnerable (www.natureserve.org/explorer). Declines in freshwater mussels are not unique to North America [5], but because the taxon reaches its greatest richness here, impacts are especially noteworthy.

  5. Retrospective environmental biomonitoring - Mussel Watch expanded

    NASA Astrophysics Data System (ADS)

    Schöne, Bernd R.; Krause, Richard A.

    2016-09-01

    Monitoring bioavailable contaminants and determining baseline conditions in aquatic environments has become an important aspect of ecology and ecotoxicology. Since the mid-1970s and the initiation of the Mussel Watch program, this has been successfully accomplished with bivalve mollusks. These (mostly) sessile organisms reliably and proportionately record changes of a range of organic and inorganic pollutants occurring in the water, food or sediment. The great majority of studies have measured the concentration of pollutants in soft tissues and, to a much lesser extent, in whole shells or fractions thereof. Both approaches come with several drawbacks. Neither soft tissues nor whole shells can resolve temporal changes of the pollution history, except through the analysis of multiple specimens collected at different times. Soft tissues and shell fractions provide time-averaged data spanning months or years, and whole shells time-averaged data over the entire lifespan of the animal. Even with regular sampling of multiple specimens over long intervals of time, the resulting chronology may not faithfully resolve short-term changes of water quality. Compounding the problem, whole shell averages tend to be non-arithmetic and non-linear, because shell growth rate varies through seasons and lifetime, and different shell layers often vary ultrastructurally and can thus be chemically different from each other. Mussel Watch could greatly benefit from the potential of bivalve shells in providing high-resolution, temporally aligned archives of environmental variability. So far, only circa a dozen studies have demonstrated that the sclerochronological approach - i.e., combined growth pattern and high-resolution chemical analyses - can provide sub-seasonally to annually resolved time-series documenting the history of pollution over centuries and even millennia. On the other hand, the sclerochronological community has failed to fully appreciate that the formation of the shell and

  6. Acute toxicity of copper, ammonia, and chlorine to glochidia and juveniles of freshwater mussels (Unionidae)

    USGS Publications Warehouse

    Wang, N.; Ingersoll, C.G.; Hardesty, D.K.; Ivey, C.D.; Kunz, J.L.; May, T.W.; Dwyer, F.J.; Roberts, A.D.; Augspurger, T.; Kane, C.M.; Neves, R.J.; Barnhart, M.C.

    2007-01-01

    The objective of the present study was to determine acute toxicity of copper, ammonia, or chlorine to larval (glochidia) and juvenile mussels using the recently published American Society for Testing and Materials (ASTM) Standard guide for conducting laboratory toxicity tests with freshwater mussels. Toxicity tests were conducted with glochidia (24- to 48-h exposures) and juveniles (96-h exposures) of up to 11 mussel species in reconstituted ASTM hard water using copper, ammonia, or chlorine as a toxicant. Copper and ammonia tests also were conducted with five commonly tested species, including cladocerans (Daphnia magna and Ceriodaphnia dubia; 48-h exposures), amphipod (Hyalella azteca; 48-h exposures), rainbow trout (Oncorhynchus mykiss; 96-h exposures), and fathead minnow (Pimephales promelas; 96-h exposures). Median effective concentrations (EC50s) for commonly tested species were >58 ??g Cu/L (except 15 ??g Cu/L for C. dubia) and >13 mg total ammonia N/L, whereas the EC50s for mussels in most cases were 40 ??g/L and above the FAV in the WQC for chlorine. The results indicate that the early life stages of mussels generally were more sensitive to copper and ammonia than other organisms and that, including mussel toxicity data in a revision to the WQC, would lower the WQC for copper or ammonia. Furthermore, including additional mussel data in 2007 WQC for copper based on biotic ligand model would further lower the WQC. ?? 2007 SETAC.

  7. Season-dependent effects of elevated temperature on stress biomarkers, energy metabolism and gamete development in mussels.

    PubMed

    Múgica, M; Sokolova, I M; Izagirre, U; Marigómez, I

    2015-02-01

    In coastal areas, sessile species can be severely affected by thermal stress associated to climate change. Presently, the effect of elevated temperature on metabolic, cellular and tissue-level responses of mussels was determined to assess whether the responses vary seasonally with seawater temperature and reproductive stage. Mussels were collected in fall, winter and summer, and (a) maintained at 16, 12, and 20 °C respectively or (b) subject to gradual temperature elevation for 8 days (+1 °C per day; from 16 to 24 °C in fall, from 12 to 20 °C in winter and from 20 to 28 °C in summer) and further maintained at 24 °C (fall), 20 °C (winter) and 28 °C (summer) for the following 6 days. Temperature elevation induced membrane destabilization, lysosomal enlargement, and reduced the aerobic scope in fall and summer whereas in winter no significant changes were found. Changes at tissue-level were only evident at 28 °C. Gamete development was impaired irrespective of season. Since the threshold of negative effects of warming was close to ambient temperatures in summer (24 °C or above) studied mussel populations would be vulnerable to the global climate change. Copyright © 2014 Elsevier Ltd. All rights reserved.

  8. Current Distributional Information on Freshwater Mussels (family Unionidae) in Mississippi National Forests

    Treesearch

    Wendell R. Haag; Melvin L. Warren

    1995-01-01

    Little is known about the distribution of freshwater mussels in Mississippi national forests. Review of the scant available information revealed that the national forests harbor a diverse mussel fauna of possibly 46 or more species (including confirmed, probable, and potential occurrences). Occurrence of 33 species is confirmed. Because of the geographic, physiographic...

  9. Occurrence, profile and spatial distribution of UV-filters and musk fragrances in mussels from Portuguese coastline.

    PubMed

    Castro, M; Fernandes, J O; Pena, A; Cunha, S C

    2018-07-01

    The increasing production and consumption of Personal Care Products (PCPs), containing UV-filters and musk fragrances, has led to its widespread presence in the aquatic environment which can cause harmful effects to the aquatic organisms due to its intrinsic toxicity. This study aims to evaluate the degree of contamination of wild mussels along the entire Portuguese coastline, continually exposed in their habitat to different contaminants. For this purpose, approximately 1000 mussel specimens were sampled during one year in seven different locations, along the Portuguese coastline. Simultaneous quantification of five UV-filters and seven musks in mussels was achieved by a Quick, Easy, Cheap, Effective, Rugged and Safe (QuEChERS) extraction procedure combined with dispersive liquid-liquid microextraction (DLLME) followed by gas chromatography with mass spectrometry (GC-MS) analysis. Ten out of the twelve target analytes were found in the analysed samples, highlighting the presence of AHTN (tonalide), EHS (2-ethylhexylsalicylate) and EHMC (2-ethylhexyl 4-methoxycinnamate) in all positive samples (93%). Overall, the results obtained indicate a widespread contamination of wild mussels along Portuguese coastline, all over the year. UV-filters were more frequently detected (90%) than musk fragrances (70%) and also quantified at higher levels, with average total concentrations reaching 1155.8 ng/g (dw) against 397.7 ng/g (dw) respectively. A high correlation was observed between the most densely populated and industrialized locations and the higher levels of musks and UV-filters found. In other hand, lower levels of PCPs were found in protected areas. As expected, an increase in UV-filters levels was observed after the summer, likely due to the intense period of recreational activities. Copyright © 2018 Elsevier Ltd. All rights reserved.

  10. Spatial and temporal trends of freshwater mussel assemblages in the Meramec River Basin, Missouri, USA

    USGS Publications Warehouse

    Hinck, Jo Ellen; McMurray, Stephen E.; Roberts, Andrew D.; Barnhart, M. Christopher; Ingersoll, Christopher G.; Wang, Ning; Augspurger, Tom

    2012-01-01

    The Meramec River basin in east-central Missouri has one of the most diverse unionoid mussel faunas in the central United States with >40 species identified. Data were analyzed from historical surveys to test whether diversity and abundance of mussels in the Meramec River basin (Big, Bourbeuse, and Meramec rivers, representing >400 river miles) decreased between 1978 and 1997. We found that over 20y, species richness and diversity decreased significantly in the Bourbeuse and Meramec rivers but not in the Big River. Most species were found at fewer sites and in lower numbers in 1997 than in 1978. Federally endangered species and Missouri Species of Conservation Concern with the most severe temporal declines were Alasmidonta viridis, Arcidens confragosus, Elliptio crassidens, Epioblasma triquetra, Fusconaia ebena, Lampsilis abrupta, Lampsilis brittsi, and Simpsonaias ambigua. Averaged across all species, mussels were generally being extirpated from historical sampling sites more rapidly than colonization was occurring. An exception was one reach of the Meramec River between river miles 28.4 and 59.5, where mussel abundance and diversity were greater than in other reaches and where colonization of Margaritiferidae, Lampsilini, and Quadrulini exceeded extirpation. The exact reasons mussel diversity and abundance have remained robust in this 30- mile reach is uncertain, but the reach is associated with increased gradients, few long pools, and vertical rock faces, all of which are preferable for mussels. Complete loss of mussel communities at eight sites (16%) with relatively diverse historical assemblages was attributed to physical habitat changes including bank erosion, unstable substrate, and sedimentation. Mussel conservation efforts, including restoring and protecting riparian habitats, limiting the effects of in-stream sand and gravel mining, monitoring and controlling invasive species, and protecting water quality, may be warranted in the Meramec River basin.

  11. Morphological and ecological determinants of body temperature of Geukensia demissa, the Atlantic ribbed mussel, and their effects on mussel mortality.

    PubMed

    Jost, Jennifer; Helmuth, Brian

    2007-10-01

    Measurements of body temperatures in the field have shown that spatial and temporal patterns are often far more complex than previously anticipated, particularly in intertidal regions, where temperatures are driven by both marine and terrestrial climates. We examined the effects of body size, body position within the sediment, and microhabitat (presence or absence of Spartina alterniflora) on the body temperature of the mussel Geukensia demissa. We then used these data to develop a laboratory study exposing mussels to an artificial "stressful" day, mimicking field conditions as closely as possible. Results suggested that G. demissa mortality increases greatly at average daily peak temperatures of 45 degrees C and higher. When these temperatures were compared to field data collected in South Carolina in the summer of 2004, our data indicated that mussels likely experienced mortality due to high-temperature stress at this site during this period. Our results also showed that body position in the mud is the most important environmental modifier of body temperature. This experiment suggested that the presence of marsh grass leads to increases in body temperature by reducing convection, overwhelming the effects of shading. These data add to a growing body of evidence showing that small-scale thermal variability can surpass large-scale gradients.

  12. Identification, localisation and functional implication of 26RFa orthologue peptide in the brain of zebra finch (Taeniopygia guttata).

    PubMed

    Tobari, Y; Iijima, N; Tsunekawa, K; Osugi, T; Haraguchi, S; Ubuka, T; Ukena, K; Okanoya, K; Tsutsui, K; Ozawa, H

    2011-09-01

    Several neuropeptides with the C-terminal Arg-Phe-NH(2) (RFa) sequence have been identified in the hypothalamus of a variety of vertebrates. The present study was conducted to isolate novel RFa peptides from the zebra finch brain. Peptides were isolated by immunoaffinity purification using an antibody that recognises avian RFa peptides. The isolated peptide consisted of 25 amino acids with RFa at its C-terminus. The sequence was SGTLGNLAEEINGYNRRKGGFTFRFa. Alignment of the peptide with vertebrate 26RFa has revealed that the identified peptide is the zebra finch 26RFa. We also cloned the precursor cDNA encoding this peptide. Synteny analysis of the gene showed a high conservation of this gene among vertebrates. In addition, we cloned the cDNA encoding a putative 26RFa receptor, G protein-coupled receptor 103 (GPR103) in the zebra finch brain. GPR103 cDNA encoded a 432 amino acid protein that has seven transmembrane domains. In situ hybridisation analysis in the brain showed that the expression of 26RFa mRNA is confined to the anterior-medial hypothalamic area, ventromedial nucleus of the hypothalamus and the lateral hypothalamic area, the brain regions that are involved in the regulation of feeding behaviour, whereas GPR103 mRNA is distributed throughout the brain in addition to the hypothalamic nuclei. When administered centrally in free-feeding male zebra finches, 26RFa increased food intake 24 h after injection without body mass change. Diencephalic GPR103 mRNA expression was up-regulated by fasting for 10 h. Our data suggest that the hypothalamic 26RFa-its receptor system plays an important role in the central control of food intake and energy homeostasis in the zebra finch. © 2011 The Authors. Journal of Neuroendocrinology © 2011 Blackwell Publishing Ltd.

  13. Organo-tins in sediments and mussels from the Sado estuarine system (Portugal).

    PubMed

    Quevauviller, P; Lavigne, R; Pinel, R; Astruc, M

    1989-01-01

    Analyses of methyl- and butyl-tin levels in freshwater, estuarine and marine sediments from the Sado estuarine system, and in mussels (Mytilus galloprovincialis) from its adjacent coast, have been performed in order to detect the contaminated areas. The main inputs of tributyl-tin (TBT), along with degradation products di- and monobutyl-tin (DBT and MBT), were detected in the estuarine zone, due to high discharge from shipyards located in this area. These levels are sometimes very high, ranging from 235 to 12,200 ng g(-1) total butyl-tins in sediments. Such inputs lead to higher bioconcentration values in mussels in the estuarine zone, as well as in a harbour located along the adjacent coast. The bioconcentration of organo-tins in mussel tissues could be enhanced in estuarine turbid waters, due to an ingestion of butyl-tins adsorbed onto fine particles, in comparison with non-turbid coastal waters. Debutylation processes occur in both sediments and mussel tissues; in organisms, these processes may lead to the formation of inorganic tin, which may be methylated differently according to the period of the year.

  14. Phagocytic activities of hemocytes from the deep-sea symbiotic mussels Bathymodiolus japonicus, B. platifrons, and B. septemdierum.

    PubMed

    Tame, Akihiro; Yoshida, Takao; Ohishi, Kazue; Maruyama, Tadashi

    2015-07-01

    Deep-sea mytilid mussels harbor symbiotic bacteria in their gill epithelial cells that are horizontally or environmentally transmitted to the next generation of hosts. To understand the immune defense system in deep-sea symbiotic mussels, we examined the hemocyte populations of the symbiotic Bathymodiolus mussel species Bathymodiolus japonicus, Bathymodiolus platifrons, and Bathymodiolus septemdierum, and characterized three types of hemocytes: agranulocytes (AGs), basophilic granulocytes (BGs), and eosinophilic granulocytes (EGs). Of these, the EG cells were the largest (diameter, 8.4-10.0 μm) and had eosinophilic cytoplasm with numerous eosinophilic granules (diameter, 0.8-1.2 μm). Meanwhile, the BGs were of medium size (diameter, 6.7-8.0 μm) and contained small basophilic granules (diameter, 0.3-0.4 μm) in basophilic cytoplasm, and the AGs, the smallest of the hemocytes (diameter, 4.8-6.0 μm), had basophilic cytoplasm lacking granules. A lectin binding assay revealed that concanavalin A bound to all three hemocyte types, while wheat germ agglutinin bound exclusively to EGs and BGs. The total hemocyte population densities within the hemolymph of all three Bathymodiolus mussel species were similar (8.4-13.3 × 10(5) cells/mL), and the percentages of circulating AGs, BGs, and EGs in the hemolymph of these organisms were 44.7-48.5%, 14.3-17.6%, and 34.3-41.0%, respectively. To analyze the functional differences between these hemocytes, the phagocytic activity and post-phagocytic phagosome-lysosome fusion events were analyzed in each cell type using a fluorescent Alexa Fluor(®) 488-conjugated Escherichia coli bioparticle and a LysoTracker(®) lysosomal marker, respectively. While the AGs exhibited no phagocytic activity, both types of granulocytes were phagocytic. Of the three hemocyte types, the EGs exhibited the highest level of phagocytic activity as well as rapid phagosome-lysosome fusion, which occurred within 2 h of incubation. Meanwhile, the BGs showed

  15. Microplastic abundances in a mussel bed and ingestion by the ribbed marsh mussel Geukensia demissa.

    PubMed

    Khan, Matthew B; Prezant, Robert S

    2018-05-01

    Human activities have generated large quantities of microplastics that can be consumed by filter-feeding organisms as potential food sources. As a result, organisms may experience marked reductions in growth and/or health. To date there has been no investigations connecting microplastics (MPs) with the critically important ribbed mussel Geukensia demissa. Here we examined MP abundances within a bed of G. demissa in New Jersey. Results indicate that MP densities ranged between 11,000-50,000 pieces/m 2 . The abundance of larger MPs (5 mm ≥ 1 mm) did not vary among sampling sites while the smaller MPs (<1 mm) abundances did vary between sampling sites. These smaller MPs also accounted for 79% of MPs recovered from these sites. Based on the higher abundance of smaller MPs, we also investigated MP ingestion/rejection in a laboratory setting. These results confirmed that ribbed mussels can ingest MPs with negative consequences for the buoyancy of plastics rejected in feces and pseudofeces. Copyright © 2018 The Authors. Published by Elsevier Ltd.. All rights reserved.

  16. Mussel biofiltration effects on attached bacteria and unicellular eukaryotes in fish-rearing seawater

    PubMed Central

    Voudanta, Eleni; Monchy, Sebastién; Delegrange, Alice; Vincent, Dorothée; Genitsaris, Savvas; Christaki, Urania

    2016-01-01

    Mussel biofiltration is a widely used approach for the mitigation of aquaculture water. In this study, we investigated the effect of mussel biofiltration on the communities of particle-associated bacteria and unicellular eukaryotes in a sea bass aquaculture in southern North Sea. We assessed the planktonic community changes before and after biofiltration based on the diversity of the 16S and 18S rRNA genes by using next generation sequencing technologies. Although there was no overall reduction in the operational taxonomic units (OTU) numbers between the control (no mussels) and the test (with mussels) tanks, a clear reduction in the relative abundance of the top three most dominant OTUs in every sampling time was observed, ranging between 2–28% and 16–82% for Bacteria and Eukarya, respectively. The bacterial community was dominated by OTUs related to phytoplankton blooms and/or high concentrations of detritus. Among the eukaryotes, several fungal and parasitic groups were found. Their relative abundance in most cases was also reduced from the control to the test tanks; a similar decreasing pattern was also observed for both major higher taxa and functional (trophic) groups. Overall, this study showed the effectiveness of mussel biofiltration on the decrease of microbiota abundance and diversity in seawater fueling fish farms. PMID:27069786

  17. Mussel biofiltration effects on attached bacteria and unicellular eukaryotes in fish-rearing seawater.

    PubMed

    Voudanta, Eleni; Kormas, Konstantinos Ar; Monchy, Sebastién; Delegrange, Alice; Vincent, Dorothée; Genitsaris, Savvas; Christaki, Urania

    2016-01-01

    Mussel biofiltration is a widely used approach for the mitigation of aquaculture water. In this study, we investigated the effect of mussel biofiltration on the communities of particle-associated bacteria and unicellular eukaryotes in a sea bass aquaculture in southern North Sea. We assessed the planktonic community changes before and after biofiltration based on the diversity of the 16S and 18S rRNA genes by using next generation sequencing technologies. Although there was no overall reduction in the operational taxonomic units (OTU) numbers between the control (no mussels) and the test (with mussels) tanks, a clear reduction in the relative abundance of the top three most dominant OTUs in every sampling time was observed, ranging between 2-28% and 16-82% for Bacteria and Eukarya, respectively. The bacterial community was dominated by OTUs related to phytoplankton blooms and/or high concentrations of detritus. Among the eukaryotes, several fungal and parasitic groups were found. Their relative abundance in most cases was also reduced from the control to the test tanks; a similar decreasing pattern was also observed for both major higher taxa and functional (trophic) groups. Overall, this study showed the effectiveness of mussel biofiltration on the decrease of microbiota abundance and diversity in seawater fueling fish farms.

  18. Global depression in gene expression as a response to rapid thermal changes in vent mussels

    PubMed Central

    Boutet, Isabelle; Tanguy, Arnaud; Le Guen, Dominique; Piccino, Patrice; Hourdez, Stéphane; Legendre, Pierre; Jollivet, Didier

    2009-01-01

    Hydrothermal vent mussels belonging to the genus Bathymodiolus are distributed worldwide and dominate communities at shallow Atlantic hydrothermal sites. While organisms inhabiting coastal ecosystems are subjected to predictable oscillations of physical and chemical variables owing to tidal cycles, the vent mussels sustain pronounced temperature changes over short periods of time, correlated to the alternation of oxic/anoxic phases. In this context, we focused on the short-term adaptive response of mussels to temperature change at a molecular level. The mRNA expression of 23 genes involved in various cell functions of the vent mussel Bathymodiolus azoricus was followed after heat shocks for either 30 or 120 min, at 25 and 30°C over a 48 h recovery period at 5°C. Mussels were genotyped at 10 enzyme loci to explore a relationship between natural genetic variation, gene expression and temperature adaptation. Results indicate that the mussel response to increasing temperature is a depression in gene expression, such a response being genotypically correlated at least for the Pgm-1 locus. This suggests that an increase in temperature could be a signal triggering anaerobiosis for B. azoricus or this latter alternatively behaves more like a ‘cold’ stenotherm species, an attribute more related to its phylogenetic history, a cold seeps/wood fall origin. PMID:19515664

  19. Using Digital Images of the Zebra Finch Song System as a Tool to Teach Organizational Effects of Steroid Hormones: A Free Downloadable Module

    PubMed Central

    Grisham, William; Schottler, Natalie A.; McCauley, Lisa M. Beck; Pham, Anh P.; Ruiz, Maureen L.; Fong, Michelle C.; Cui, Xinran

    2011-01-01

    Zebra finch song behavior is sexually dimorphic: males sing and females do not. The neural system underlying this behavior is sexually dimorphic, and this sex difference is easy to quantify. During development, the zebra finch song system can be altered by steroid hormones, specifically estradiol, which actually masculinizes it. Because of the ease of quantification and experimental manipulation, the zebra finch song system has great potential for use in undergraduate labs. Unfortunately, the underlying costs prohibit use of this system in undergraduate labs. Further, the time required to perform a developmental study renders such undertakings unrealistic within a single academic term. We have overcome these barriers by creating digital tools, including an image library of song nuclei from zebra finch brains. Students using this library replicate and extend a published experiment examining the dose of estradiol required to masculinize the female zebra finch brain. We have used this library for several terms, and students not only obtain significant experimental results but also make gains in understanding content, experimental controls, and inferential statistics (analysis of variance and post hoc tests). We have provided free access to these digital tools at the following website: http://mdcune.psych.ucla.edu/modules/birdsong. PMID:21633071

  20. Mussel mimetic tissue adhesive for fetal membrane repair: initial in vivo investigation in rabbits.

    PubMed

    Kivelio, A; Dekoninck, P; Perrini, M; Brubaker, C E; Messersmith, P B; Mazza, E; Deprest, J; Zimmermann, R; Ehrbar, M; Ochsenbein-Koelble, N

    2013-12-01

    Iatrogenic preterm prelabour rupture of fetal membranes (iPPROM) remains the main complication after invasive interventions into the intrauterine cavity. The aim of this study was to evaluate the sealing capability and tissue interaction of mussel-mimetic tissue adhesive (mussel glue) in comparison to fibrin glue on punctured fetal membranes in vivo. A mid-gestational rabbit model was used for testing the materials. The fetal sacs of pregnant rabbits at day 23 were randomly assigned into experimental groups: unoperated (negative control), unclosed puncture (positive control), commercially available fibrin glue (FG) with decellularized amnion scaffold (DAM), mussel glue (MG) with DAM, or mussel glue alone. Evaluation was done at term (30 days' gestation) assessing fetal survival, fetal membrane integrity and histology of the membranes. Fetal survival was not significantly lower in any of the treatment groups compared to the negative control. All plugging materials could be found at the end of the pregnancy and no adverse effects on the fetus or the pregnant does could be observed. Sac integrity was higher in all treatment groups compared to the positive control group but significant only in the FG+DAM group. Cellular infiltration could be seen in fibrin glue and DAM in contrast to mussel glue which was only tightly adhering to the surrounding tissue. These cells were mostly of mesenchymal phenotype staining positive for vimentin. CD68 positive macrophages were found clustered around all the plugging materials, but their numbers were only significantly increased for the mussel glue alone group compared to negative controls. Mussel glues performance in sealing fetal membranes in the rabbit model was comparable to that of fibrin glue. Taking into account its other favorable properties, it is a noteworthy candidate for a clinically applicable fetal membrane sealant. Copyright © 2013 Elsevier Ireland Ltd. All rights reserved.

  1. The effect of UV-C exposure on larval survival of the dreissenid quagga mussel

    USGS Publications Warehouse

    Stewart-Malone, Alecia; Misamore, Michael; Wilmoth, Siri K.; Reyes, Alejandro; Wong, Wai Hing; Gross, Jackson

    2015-01-01

    The rapid spread of quagga mussels (Dreissena rostriformis bugensis) has lead to their invasion of Lake Mead, Nevada, the largest reservoir in North America and partially responsible for providing water to millions of people in the southwest. Current strategies for mitigating the growth and spread of quagga mussels primarily include physical and chemical means of removing adults within water treatment, delivery, and hydropower facilities. In the present study, germicidal ultraviolet light (UV-C) was used to target the larval stage of wild-caught quagga mussel. The lethal effect of UV-C was evaluated at four different doses, 0.0, 13.1, 26.2, and 79.6 mJ/cm2. Tested doses were determined based on results from preliminary trials. The results demonstrate that germicidal UV-C is effective in controlling the free-swimming life history stages of larval quagga mussels.

  2. The Effect of UV-C Exposure on Larval Survival of the Dreissenid Quagga Mussel

    PubMed Central

    Stewart-Malone, Alecia; Misamore, Michael; Wilmoth, Siri; Reyes, Alejandro; Wong, Wai Hing; Gross, Jackson

    2015-01-01

    The rapid spread of quagga mussels (Dreissena rostriformis bugensis) has lead to their invasion of Lake Mead, Nevada, the largest reservoir in North America and partially responsible for providing water to millions of people in the southwest. Current strategies for mitigating the growth and spread of quagga mussels primarily include physical and chemical means of removing adults within water treatment, delivery, and hydropower facilities. In the present study, germicidal ultraviolet light (UV-C) was used to target the larval stage of wild-caught quagga mussel. The lethal effect of UV-C was evaluated at four different doses, 0.0, 13.1, 26.2, and 79.6 mJ/cm2. Tested doses were determined based on results from preliminary trials. The results demonstrate that germicidal UV-C is effective in controlling the free-swimming life history stages of larval quagga mussels. PMID:26186734

  3. Metal interactions between the polychaete Branchipolynoe seepensis and the mussel Bathymodiolus azoricus from Mid-Atlantic-Ridge hydrothermal vent fields.

    PubMed

    Bebianno, Maria João; Cardoso, Cátia; Gomes, Tânia; Blasco, Julian; Santos, Ricardo Serrão; Colaço, Ana

    2018-04-01

    The vent blood-red commensal polynoid polychaete Branchipolynoe seepensis is commonly found in the pallial cavity of the vent mussel Bathymodiolus azoricus, the dominant bivalve species along the Mid-Atlantic-Ridge (MAR) and is known to be kleptoparasitic. Mussels were collected from three hydrothermal vent fields in the MAR: Menez Gwen (850 m depth, MG2, MG3 and MG4), Lucky Strike (1700 m depth, Montségur-MS and Eiffel Tower-ET) and Rainbow (2300 m depth). Polychaetes were absent in all Menez Gwen vent mussels, while the highest percentage was detected in mussels from Lucky Strike, where more than 70% of the mussels had at least one polychaete in their mantle cavity, followed by Rainbow with 33% of mussels with polychaetes. Total metal concentrations (Ag, Cd, Co, Cu, Fe, Mn, Ni and Zn) were determined in polychaetes whole body and in the mussel tissues (gills, digestive gland and mantle). To understand the possible metal interactions between symbiont and host, the activity of antioxidant defence (catalase (CAT), metallothioneins (MTs)), biotransformation enzymes (glutathione-s-transferases (GST)) activities and lipid peroxidation (LPO) were determined in polychaete whole soft tissues and in mussel tissues (gills, digestive gland and mantle). Metal concentrations in polychaetes and mussels tissues indicated that the accumulation patterns were species specific and also influenced by, and possibly dependent upon, the inter- and intra-variation of vent physico-chemistry between hydrothermal fields. Despite not detecting any strong correlations between metal and enzymes activities in polychaetes and mussels, when in presence of polychaetes, mussels presented less metal concentrations in the gills and digestive gland and lower activity of enzymatic biomarkers. This leads to infer that the polychaete plays a role on the detoxification process, and the interaction between the polychaete mussel association is probably an adaptation to metals concentrations at the

  4. Importance of benthic production to fish populations in Lake Mead prior to the establishment of quagga mussels

    USGS Publications Warehouse

    Umek, John; Chandra, Sudeep; Rosen, Michael; Wittmann, Marion; Sullivan, Joe; Orsak, Erik

    2010-01-01

    Limnologists recently have developed an interest in quantifying benthic resource contributions to higher-level consumers. Much of this research focuses on natural lakes with very little research in reservoirs. In this study, we provide a contemporary snapshot of the food web structure of Lake Mead to evaluate the contribution of benthic resources to fish consumers. In addition, we document the available food to fishes on soft sediments and changes to the invertebrate community over 2 time periods. Benthic invertebrate food availability for fishes is greater in Las Vegas Bay than Overton Arm. Las Vegas Bay is dominated by oligochaetes, whose biomass increased with depth, while Overton Arm is dominated by chironomids, whose biomass did not change with depth. Diet and isotopic measurements indicate the fish community largely relies on benthic resources regardless of basin (Las Vegas Bay >80%; Overton Arm >92%); however, the threadfin shad likely contribute more to largemouth and striped bass production in Overton Arm versus Las Vegas Bay. A 2-time period analysis, pre and post quagga mussel establishment and during lake level declines, suggests there is no change in the density of benthic invertebrates in Boulder Basin, but there were greater abundances of select taxa in this basin by season and depth than in other basins. Given the potential of alterations as a result of the expansion of quagga mussel and the reliance of the fishery on benthic resources, future investigation of basin specific, benthic processes is recommended.

  5. Methallothionein expression on the gills and stomach of Chinese pond mussels exposed to lead (Pb)

    NASA Astrophysics Data System (ADS)

    Kartikaningsih, H.; Suryanto, A. M.; Arfiati, D.

    2018-04-01

    In freshwaters area, Pb originates from rocks (naturally), industries, and pesticides. The ability of Chinese pond mussels as biofilters to absorb heavy metal (Pb) was demonstrated in water circulation system using ten 8 cm mussels. PbNO3 (0, 10, 20, and 30 ppm) was administered into water containing mussels. Carp culture was done for 30 days, and Pb accumulation in carps was measured every week (week 0, 1, 2, and 3). The results showed that the highest Pb ion accumulation was found in the gills of mussels. The examination using hematoxylin-eosin showed that tissues were damage due to haemorrhage, cell ruptures, and cell deaths. The results of the measurement of metallothionein (MT) showed that MT molecular weight was 12.84 kDa.

  6. Identifying the optimal depth for mussel suspended culture in shallow and turbid environments

    NASA Astrophysics Data System (ADS)

    Filgueira, Ramón; Grant, Jon; Petersen, Jens Kjerulf

    2018-02-01

    Bivalve aquaculture is commonly carried out in shallow water systems, which are susceptible to resuspension of benthic particulate matter by natural processes such as tidal currents, winds and wave action, as well as human activity. The resuspended material can alter the availability of food particles for cultured bivalves. The effect of resuspended material on bivalve bioenergetics and growth is a function of the quality and concentration of resuspended particles and background diet in the water column. Given the potential for positive or negative impacts on bivalve growth and consequently on farm productivity, farmers must position the cultured biomass at the appropriate depth to benefit from or mitigate the impact of this resuspended material. A combination of field measurements, a 1-D vertical resuspension model and a bioenergetic model for mussels based on Dynamic Energy Budget (DEB) theory has been carried out for a mussel farm in Skive Fjord, a shallow Danish fjord, with the aim of identifying the optimal depth for culture. Observations at the farm location revealed that horizontal advection is more important than vertical resuspension during periods with predominant Eastern winds. In addition, high background seston in the water column reduces the impact of resuspension on the available food for mussels. The simulation of different scenarios in terms of food availability suggested minimal effects of resuspension on mussel growth. Based on this finding and the fact that phytoplankton concentration, the main food source for mussels, is usually higher in the upper part of the water column, suspended culture in the top 3 m of the water column seems to be the optimal practice to produce mussels in Skive Fjord.

  7. Non-invasive method to obtain DNA from freshwater mussels (Bivalvia: Unionidae)

    USGS Publications Warehouse

    Henley, W.F.; Grobler, P.J.; Neves, R.J.

    2006-01-01

    To determine whether DNA could be isolated from tissues obtained by brush-swabbing the mantle, viscera and foot, mantle-clips and swabbed cells were obtained from eight Quadrula pustulosa (Lea, 1831). DNA yields from clips and swabbings were 447.0 and 975.3 ??g/??L, respectively. Furthermore, comparisons of sequences from the ND-1 mitochondrial gene region showed a 100% sequence agreement of DNA from cells obtained by clips and swabs. To determine the number of swabs needed to obtain adequate yields of DNA for analyses, the visceras and feet of 5 Q. pustulosa each were successively swabbed 2, 4 and 6 times. DNA yields from the 2, 4 and 6 swabbed mussel groups were 399.4, 833.8 and 852.6 ng/??L, respectively. ND-1 sequences from the lowest yield still provided 846-901 bp for the ND-1 region. Nevertheless, to ensure adequate DNA yield from cell samples obtained by swabbing, we recommend that 4 swab-strokes of the viscera and foot be obtained. The use of integumental swabbing for collection of cells for determination of genetic relationships among freshwater mussels is noninvasive, when compared with tissue collection by mantle-clipping. Therefore, its use is recommended for freshwater mussels, especially state-protected or federally listed mussel species.

  8. An Investigation of Freshwater Mussels (Unionidae) in the Tennessee River below Kentucky Lock and Dam.

    DTIC Science & Technology

    1991-07-01

    Division of Water , Murray, KY. Sickel, J. B. 1987. "Survey of Freshwater Mussels in the Kentucky Dam Tailwater at the Site of the Proposed Reed...AN]ITECHNICAL REPORT EL-91-8 AN INVESTIGATION OF FRESHWATER MUSSELS (UNiONIDAE) IN THE TENNESSEE RIVER BELOW KENTUCKY LOCK AND DAM by ADA 24 0 265...SUBTITLE S. FUNDING NUMBERS An Investigation of Freshwater Mussels (Unionidae) in the Tennessee River Below Kentucky Lock and Dam 6. AUTHOR(S) Andrew C

  9. Shifts in stable-isotope signatures confirm parasitic relationship of freshwater mussel glochidia attached to host fish

    USGS Publications Warehouse

    Fritts, Mark W.; Fritts, Andrea K.; Carleton, Scott A.; Bringolf, Robert B.

    2013-01-01

    The parasitic nature of the association between glochidia of unionoidean bivalves and their host fish (i.e. the role of fish hosts in providing nutritional resources to the developing glochidia) is still uncertain. While previous work has provided descriptions of development of glochidia on fish hosts, earlier studies have not explicitly documented the flow of nutrition from the host fish to the juvenile mussel. Therefore, our objective was to use stable isotope analysis to quantitatively document nutrient flow between fish and glochidia. Glochidia were collected from nine adult Lampsilis cardium and used to inoculate Micropterus salmoides(n = 27; three fish per maternal mussel) that produced juvenile mussels for the experiment. Adult mussel tissue samples, glochidia, transformed juvenile mussels and fish gill tissues were analysed for δ15N and δ13C isotope ratios. We used a linear mixing model to estimate the fraction of juvenile mussel tissue derived from the host fish's tissue during attachment. Our analyses indicate a distinct shift in both C and N isotopic ratios from the glochidial stage to the juvenile stage during mussel attachment and development. Linear mixing model analysis indicated that 57.4% of the δ15N in juvenile tissues were obtained from the host fish. This work provides novel evidence that larval unionoideans are true parasites that derive nutrition from host fish during their metamorphosis into the juvenile stage.

  10. The Impact of Extreme Flooding on Mussel and Microbial Nutrient Dynamics at the Water-Sediment Interface

    NASA Astrophysics Data System (ADS)

    Bril, J.; Just, C. L.; Newton, T.; Young, N.; Parkin, G.

    2009-12-01

    Labeled by the National Academy of Engineering as one of fourteen grand challenges for engineering, the management of the nitrogen cycle has become an increasingly difficult obstacle for sustainable development. In an effort to improve nitrogen cycle management practices, we are attempting to expand on the limited scientific knowledge of how aquatic environments are affected by increasing human- and climate-induced changes. To accomplish this, we are using freshwater mussels as a sentinel species to indicate how natural processes within large river systems may be altered by human activity. Freshwater mussels have been referred to as ‘ecosystem engineers’ because they exert control over food resources and alter habitats for other organisms. Also, mussels and bacteria play a major role in nutrient cycling in large river systems by cycling nutrients taken up by phytoplankton and zooplankton. Under ‘normal’ environmental conditions, mussels appear to process nitrogen more rapidly than denitrifying bacteria. However, substantial deposition of carbon-rich sediment resulting from extreme flooding may increase bacterial nitrogen cycling rates and subsequently alter overall denitrification rates. We hypothesize that intense depositions of particulate matter from recent extreme floods in the Upper Mississippi River Basin (UMRB) have altered the freshwater mussel and microbial food webs through physical and chemical means. This work will be done in a 1200-m reach of the UMRB near Buffalo, Iowa. The reach contains a healthy and diverse assemblage of freshwater mussels. A historic flood event during May-July 2008 coincided with intense spring cultivation and nutrient application activities in the heavily farmed landscape of the Upper Midwest and resulted in a significant pulse of agricultural contaminants to the UMRB. This led scientists to predict an almost unprecedented delivery of sediment and nutrients to the mussel bed, the broader Mississippi River, and ultimately

  11. Locally extensive meningoencephalitis caused by Miamiensis avidus (syn. Philasterides dicentrarchi) in a zebra shark.

    PubMed

    Li, Wen-Ta; Lo, Chieh; Su, Chen-Yi; Kuo, Hsuan; Lin, Susanne Je-Han; Chang, Hui-Wei; Pang, Victor Fei; Jeng, Chian-Ren

    2017-10-18

    Scuticociliatosis, caused by ciliated protozoa in the subclass Scuticociliatia of the phylum Ciliophora, can cause fatal disease in teleost fish species. However, information on scuticociliatosis in elasmobranchs is still scarce. In this report, we describe a case of locally extensive meningoencephalitis caused by Miamiensis avidus (syn. Philasterides dicentrarchi) in a 2 yr old captive zebra shark Stegostoma fasciatum. Granulocytic meningoencephalitis was observed through histological assessment. Inflammation was confined to the ventral aspect of the brain with a large number of ciliated protozoa, transforming into non-suppurative meningitis in the lateral aspect, and gradually vanished in the dorsal aspect. No histopathological and polymerase chain reaction (PCR) evidence of systemic dissemination of M. avidus was found. PCR targeting the gene coding the small-subunit ribosomal RNA (SSUrRNA) of M. avidus was performed on the brain, liver, and gill tissues, and only brain tissue yielded a positive result. The DNA sequences from amplicons of the protozoal SSUrRNA gene were completely matched to that of M. avidus. The distribution of protozoa in the current case was mainly located in the brain and suggests the possibility of a direct neural invasive pathway of M. avidus through the nasal cavity/ampullary system and/or a unique tissue tropism of M. avidus specific to the brain in zebra sharks. Further investigations on the pathogenesis of M. avidus in elasmobranchs, especially zebra sharks, are needed.

  12. Cormorant predation and the population dynamics of walleye and yellow perch in Oneida Lake

    USGS Publications Warehouse

    Rudstam, L. G.; VanDeValk, A.J.; Adams, C.M.; Coleman, J.T.H.; Forney, J.L.; Richmond, M.E.

    2004-01-01

    Double-crested Cormorants (Phalacrocorax auritus) increased dramatically in North America during the 1990s, providing the opportunity to study the effects of an increase of a top predator on an existing predator-prey system. In Oneida Lake, New York, USA, Double-crested Cormorants were first observed nesting in 1984 and had increased to over 360 nesting pairs by 2000. Concomitant with this increase in piscivorous birds was a decrease in the adult walleye (Stizostedion vitreum) and yellow perch (Perca flavescens) populations. Analysis of a 40-yr data series shows higher mortality of subadults (age 1-2 yr perch and age 1-3 yr walleye) for both species in the 1990s compared to the previous three decades. Cormorant diet was investigated from 1995 to 2000 using a combination of cast pellets, regurgitants, and stomach analysis. Walleye and yellow perch were a major portion of the cormorant diet during these years (40-82% by number). The number of subadult walleye and yellow perch consumed by cormorants suggests that the increase in subadult mortality can be explained by predation from cormorants. Mean mortality rates of adult percids attributed to cormorant predation were 1.1% per year for walleye and 7.7% per year for yellow perch. Our analysis suggests that predation by cormorants on subadult percids is a major factor contributing to the decline in both the walleye and the yellow perch populations in Oneida Lake. Other ecosystem changes (zebra mussels, lower nutrient loading, decrease in alternate prey) are not likely explanations because the potential mechanisms involved are not consistent with auxiliary data from the lake and would not affect subadult mortality. The likely impact of bird predation on percid populations in Oneida Lake occurs because cormorants feed on larger fish that are beyond the size range where compensatory mechanisms are important.

  13. Biomechanics of predator-prey arms race in lion, zebra, cheetah and impala.

    PubMed

    Wilson, Alan M; Hubel, Tatjana Y; Wilshin, Simon D; Lowe, John C; Lorenc, Maja; Dewhirst, Oliver P; Bartlam-Brooks, Hattie L A; Diack, Rebecca; Bennitt, Emily; Golabek, Krystyna A; Woledge, Roger C; McNutt, J Weldon; Curtin, Nancy A; West, Timothy G

    2018-02-08

    The fastest and most manoeuvrable terrestrial animals are found in savannah habitats, where predators chase and capture running prey. Hunt outcome and success rate are critical to survival, so both predator and prey should evolve to be faster and/or more manoeuvrable. Here we compare locomotor characteristics in two pursuit predator-prey pairs, lion-zebra and cheetah-impala, in their natural savannah habitat in Botswana. We show that although cheetahs and impalas were universally more athletic than lions and zebras in terms of speed, acceleration and turning, within each predator-prey pair, the predators had 20% higher muscle fibre power than prey, 37% greater acceleration and 72% greater deceleration capacity than their prey. We simulated hunt dynamics with these data and showed that hunts at lower speeds enable prey to use their maximum manoeuvring capacity and favour prey survival, and that the predator needs to be more athletic than its prey to sustain a viable success rate.

  14. Biomechanics of predator-prey arms race in lion, zebra, cheetah and impala

    NASA Astrophysics Data System (ADS)

    Wilson, Alan M.; Hubel, Tatjana Y.; Wilshin, Simon D.; Lowe, John C.; Lorenc, Maja; Dewhirst, Oliver P.; Bartlam-Brooks, Hattie L. A.; Diack, Rebecca; Bennitt, Emily; Golabek, Krystyna A.; Woledge, Roger C.; McNutt, J. Weldon; Curtin, Nancy A.; West, Timothy G.

    2018-02-01

    The fastest and most manoeuvrable terrestrial animals are found in savannah habitats, where predators chase and capture running prey. Hunt outcome and success rate are critical to survival, so both predator and prey should evolve to be faster and/or more manoeuvrable. Here we compare locomotor characteristics in two pursuit predator-prey pairs, lion-zebra and cheetah-impala, in their natural savannah habitat in Botswana. We show that although cheetahs and impalas were universally more athletic than lions and zebras in terms of speed, acceleration and turning, within each predator-prey pair, the predators had 20% higher muscle fibre power than prey, 37% greater acceleration and 72% greater deceleration capacity than their prey. We simulated hunt dynamics with these data and showed that hunts at lower speeds enable prey to use their maximum manoeuvring capacity and favour prey survival, and that the predator needs to be more athletic than its prey to sustain a viable success rate.

  15. Primary structure of pancreatic polypeptide from four species of Perissodactyla (Przewalski's horse, zebra, rhino, tapir).

    PubMed

    Henry, J S; Lance, V A; Conlon, J M

    1991-12-01

    Pancreatic polypeptide (PP) has been purified from extracts of the pancreas of four species of odd-toed ungulates (Perissodactyla): Przewalski's horse, mountain zebra, white rhinoceros, and mountain tapir. The amino acid sequence of Przewalski's horse pancreatic polypeptide was established as Ala-Pro-Met-Glu-Pro-Val-Tyr-Pro-Gly-Asp10-Asn- Ala-Thr-Pro-Glu-Gln-Met-Ala-Gln-Tyr20-Ala-Ala-Glu-Leu-Arg-Arg-Tyr- Ile-Asn-Met30 - Leu-Thr-Arg-Pro-Arg-Tyr.NH2. Zebra PP was identical to Przewalski's horse PP, rhinoceros PP contained three substitutions relative to the horse (Ser for Ala1, Leu for Met3, and Glu for Gln16), and tapir PP contained one substitution relative to the horse (Leu for Met3). On the basis of morphological characteristics and the fossil record, the rhinocerotids are classified with the tapirids in the suborder Ceratomorpha, whereas the horse and zebra belong to a separate suborder, Hippomorpha. On the basis of structural similarity of the PP molecules, however, it would appear that the tapir is more closely related to the horse than to the rhinoceros. These observations provide a further example of the need for extreme caution when inferring taxonomic or phylogenetic relationships between species from the structures of homologous peptides.

  16. Using Zebra-speech to study sequential and simultaneous speech segregation in a cochlear-implant simulation.

    PubMed

    Gaudrain, Etienne; Carlyon, Robert P

    2013-01-01

    Previous studies have suggested that cochlear implant users may have particular difficulties exploiting opportunities to glimpse clear segments of a target speech signal in the presence of a fluctuating masker. Although it has been proposed that this difficulty is associated with a deficit in linking the glimpsed segments across time, the details of this mechanism are yet to be explained. The present study introduces a method called Zebra-speech developed to investigate the relative contribution of simultaneous and sequential segregation mechanisms in concurrent speech perception, using a noise-band vocoder to simulate cochlear implants. One experiment showed that the saliency of the difference between the target and the masker is a key factor for Zebra-speech perception, as it is for sequential segregation. Furthermore, forward masking played little or no role, confirming that intelligibility was not limited by energetic masking but by across-time linkage abilities. In another experiment, a binaural cue was used to distinguish the target and the masker. It showed that the relative contribution of simultaneous and sequential segregation depended on the spectral resolution, with listeners relying more on sequential segregation when the spectral resolution was reduced. The potential of Zebra-speech as a segregation enhancement strategy for cochlear implants is discussed.

  17. Using Zebra-speech to study sequential and simultaneous speech segregation in a cochlear-implant simulation

    PubMed Central

    Gaudrain, Etienne; Carlyon, Robert P.

    2013-01-01

    Previous studies have suggested that cochlear implant users may have particular difficulties exploiting opportunities to glimpse clear segments of a target speech signal in the presence of a fluctuating masker. Although it has been proposed that this difficulty is associated with a deficit in linking the glimpsed segments across time, the details of this mechanism are yet to be explained. The present study introduces a method called Zebra-speech developed to investigate the relative contribution of simultaneous and sequential segregation mechanisms in concurrent speech perception, using a noise-band vocoder to simulate cochlear implants. One experiment showed that the saliency of the difference between the target and the masker is a key factor for Zebra-speech perception, as it is for sequential segregation. Furthermore, forward masking played little or no role, confirming that intelligibility was not limited by energetic masking but by across-time linkage abilities. In another experiment, a binaural cue was used to distinguish target and masker. It showed that the relative contribution of simultaneous and sequential segregation depended on the spectral resolution, with listeners relying more on sequential segregation when the spectral resolution was reduced. The potential of Zebra-speech as a segregation enhancement strategy for cochlear implants is discussed. PMID:23297922

  18. Adhesion beyond the interface: Molecular adaptations of the mussel byssus to the intertidal zone

    NASA Astrophysics Data System (ADS)

    MIller, Dusty Rose

    The California mussel, Mytilus californianus, adheres robustly in the high-energy and oxidizing intertidal zone with a fibrous holdfast called the byssus using 3,4-dihydroxyphenyl-L-alanine (Dopa)-containing adhesive mussel foot proteins (mfps). There are many supporting roles to mussel adhesion that are intimately linked and ultimately responsible for mussel byssus's durable and dynamic adhesion. This dissertation explores these supporting mechanisms, including delivery of materials underwater, iron binding, friction, and antioxidant activity. As the outermost covering of the byssus, the cuticle deserves particular attention for its supporting roles to adhesion including the high stiffness and extensibility of the M. californianus byssal cuticle, which make it one of the most energy tolerant materials known. The cuticle's matrix-granule composite structure contributes to its toughness by microcracking between its harder granules and softer matrix. We investigated delivery of cuticular material underwater, cohesion of cuticle proteins, and surface damage mitigation by cuticle protein-based coacervates. To investigate underwater material delivery, we made cuticle matrix mimics by coacervating a key cuticular protein, Mytilus californianus foot protein 1, mfp-1, with hyaluronic acid. These matrix mimics coacervated over a wide range of solution conditions, delivered concentrated material, settled on and coated surfaces underwater. Because the granules are composed of mfp-1 condensed with iron, we used the surface forces apparatus to investigate the effects of iron on the cohesion of mfp-1 from two different species of mussels and found that subtle sequence variations modulate cohesion. Using the coacervate matrix mimics and, modeling the granules as a hard surface (mica), we investigated the wear protection of coacervated mfp-1/HA to mica under frictional shear and found that preventing wear depends critically on the presence of Dopa groups. In addition to cuticle

  19. A Daily Oscillation in the Fundamental Frequency and Amplitude of Harmonic Syllables of Zebra Finch Song

    PubMed Central

    Wood, William E.; Osseward, Peter J.; Roseberry, Thomas K.; Perkel, David J.

    2013-01-01

    Complex motor skills are more difficult to perform at certain points in the day (for example, shortly after waking), but the daily trajectory of motor-skill error is more difficult to predict. By undertaking a quantitative analysis of the fundamental frequency (FF) and amplitude of hundreds of zebra finch syllables per animal per day, we find that zebra finch song follows a previously undescribed daily oscillation. The FF and amplitude of harmonic syllables rises across the morning, reaching a peak near mid-day, and then falls again in the late afternoon until sleep. This oscillation, although somewhat variable, is consistent across days and across animals and does not require serotonin, as animals with serotonergic lesions maintained daily oscillations. We hypothesize that this oscillation is driven by underlying physiological factors which could be shared with other taxa. Song production in zebra finches is a model system for studying complex learned behavior because of the ease of gathering comprehensive behavioral data and the tractability of the underlying neural circuitry. The daily oscillation that we describe promises to reveal new insights into how time of day affects the ability to accomplish a variety of complex learned motor skills. PMID:24312654

  20. Zebra pattern in decametric radio emission of Jupiter

    NASA Astrophysics Data System (ADS)

    Panchenko, M.; Rošker, S.; Rucker, H. O.; Brazhenko, A.; Zarka, P.; Litvinenko, G.; Shaposhnikov, V. E.; Konovalenko, A. A.; Melnik, V.; Franzuzenko, A. V.; Schiemel, J.

    2018-03-01

    We report the systematic analysis of zebra-like fine spectral structures in decametric frequency range of Jovian radio emission. Observations were performed by the large ground-based radio telescope URAN-2 during three observation campaigns between, Sep., 2012, and May, 2015. In total, 51 zebra pattern (ZP) events were detected. These rare fine radio features are observed in frequency range from 12.5 to 29.7 MHz as quasi-harmonically related bands of enhanced brightness. ZPs are strongly polarized radio emission with a duration from 20 s to 290 s and flux densities 105-106 Jy (normalized to 1 AU), that is, 1-2 orders lower than for Io-decametric radio emission (DAM). Occurrence of the events does not depend on the position of Io satellite but is strongly controlled by the Jovian central meridian longitude (CML). ZPs are mainly detected in two active sectors of Jovian CMLs: 100∘ to 160∘ for Northern sources (right-handed polarized) and 300∘ and 60∘ (via 360∘) for the Southern sources (left-handed). The frequency interval between neighboring stripes is from 0.26 to 1.5 MHz and in most cases this interval increases with frequency. We discussed the double plasma resonance with electrons or ions as a possible source of the ZPs. The performed analysis of the observations allows us to conclude that the observed ZPs are a new type of narrow band spectral structures in the Jovian DAM.

  1. Reproductive characteristics of a population of the washboard mussel Megalonaias nervosa (Rafinesque 1820) in the upper Mississippi River

    USGS Publications Warehouse

    Woody, C.A.; Holland-Bartels, L.

    1993-01-01

    The authors examined monthly and age-specific gametogenic development of the washboard mussel, Megalonaias nervosa, from April 1986 to March 1987 in navigation Pool 10 of the upper Mississippi River. The authors found M. nervosa to be a late tachytictic breeder. Female marsupia contained eggs or glochidia primarily from August (17 degree C) through October (9 degree C). Males were mature from July through October. Most females released their glochidia in October. Only one female was gravid in Nov (3 degree C). Most mussels were sexually mature at 8 years of age and then had an estimated average size of 68 mm (shell height). Only 8% of individuals less than or equal to 4 years of age showed any degree of reproductive development, while > 90% of age 5 and older individuals had recognizable reproductive material present. In host specificity studies, three fish species were verified as hosts for the glochidial stage. Green sunfish (Lepomis cyanellus), black bullhead (Ictalurus melas), and channel catfish (Ictalurus punctatus) produced juveniles after 26-28 days at 17 degree C. White suckers (Catastomus commersoni) and yellow perch (Perca flavescens) retained glochidia from 23 up to 26 days, but no juveniles were produced. Glochidia remained attached to common carp (Cyprinus carpio) and fathead minnows (Pimephales promelas) less than or equal to 3 days. Channel catfish were retested at 12 degree C and produced juveniles after 56 days.

  2. MytiBase: a knowledgebase of mussel (M. galloprovincialis) transcribed sequences

    PubMed Central

    Venier, Paola; De Pittà, Cristiano; Bernante, Filippo; Varotto, Laura; De Nardi, Barbara; Bovo, Giuseppe; Roch, Philippe; Novoa, Beatriz; Figueras, Antonio; Pallavicini, Alberto; Lanfranchi, Gerolamo

    2009-01-01

    Background Although Bivalves are among the most studied marine organisms due to their ecological role, economic importance and use in pollution biomonitoring, very little information is available on the genome sequences of mussels. This study reports the functional analysis of a large-scale Expressed Sequence Tag (EST) sequencing from different tissues of Mytilus galloprovincialis (the Mediterranean mussel) challenged with toxic pollutants, temperature and potentially pathogenic bacteria. Results We have constructed and sequenced seventeen cDNA libraries from different Mediterranean mussel tissues: gills, digestive gland, foot, anterior and posterior adductor muscle, mantle and haemocytes. A total of 24,939 clones were sequenced from these libraries generating 18,788 high-quality ESTs which were assembled into 2,446 overlapping clusters and 4,666 singletons resulting in a total of 7,112 non-redundant sequences. In particular, a high-quality normalized cDNA library (Nor01) was constructed as determined by the high rate of gene discovery (65.6%). Bioinformatic screening of the non-redundant M. galloprovincialis sequences identified 159 microsatellite-containing ESTs. Clusters, consensuses, related similarities and gene ontology searches have been organized in a dedicated, searchable database . Conclusion We defined the first species-specific catalogue of M. galloprovincialis ESTs including 7,112 unique transcribed sequences. Putative microsatellite markers were identified. This annotated catalogue represents a valuable platform for expression studies, marker validation and genetic linkage analysis for investigations in the biology of Mediterranean mussels. PMID:19203376

  3. "Bird Song Metronomics": Isochronous Organization of Zebra Finch Song Rhythm.

    PubMed

    Norton, Philipp; Scharff, Constance

    2016-01-01

    The human capacity for speech and vocal music depends on vocal imitation. Songbirds, in contrast to non-human primates, share this vocal production learning with humans. The process through which birds and humans learn many of their vocalizations as well as the underlying neural system exhibit a number of striking parallels and have been widely researched. In contrast, rhythm, a key feature of language, and music, has received surprisingly little attention in songbirds. Investigating temporal periodicity in bird song has the potential to inform the relationship between neural mechanisms and behavioral output and can also provide insight into the biology and evolution of musicality. Here we present a method to analyze birdsong for an underlying rhythmic regularity. Using the intervals from one note onset to the next as input, we found for each bird an isochronous sequence of time stamps, a "signal-derived pulse," or pulse(S), of which a subset aligned with all note onsets of the bird's song. Fourier analysis corroborated these results. To determine whether this finding was just a byproduct of the duration of notes and intervals typical for zebra finches but not dependent on the individual duration of elements and the sequence in which they are sung, we compared natural songs to models of artificial songs. Note onsets of natural song deviated from the pulse(S) significantly less than those of artificial songs with randomized note and gap durations. Thus, male zebra finch song has the regularity required for a listener to extract a perceived pulse (pulse(P)), as yet untested. Strikingly, in our study, pulses(S) that best fit note onsets often also coincided with the transitions between sub-note elements within complex notes, corresponding to neuromuscular gestures. Gesture durations often equaled one or more pulse(S) periods. This suggests that gesture duration constitutes the basic element of the temporal hierarchy of zebra finch song rhythm, an interesting parallel

  4. Kinetic determinations of trace element bioaccumulation in the mussel Mytilus edulis

    USGS Publications Warehouse

    Wang, W.-X.; Fisher, N.S.; Luoma, S.N.

    1996-01-01

    Laboratory experiments employing radiotracer methodology were conducted to determine the assimilation efficiencies from ingested natural seston, the influx rates from the dissolved phase and the efflux rates of 6 trace elements (Ag, Am, Cd, Co, Se and Zn) in the mussel Mytilus edulis. A kinetic model was then employed to predict trace element concentration in mussel tissues in 2 locations for which mussel and environmental data are well described: South San Francisco Bay (California, USA) and Long Island Sound (New York, USA). Assimilation efficiencies from natural seston ranged from 5 to 18% for Ag, 0.6 to 1% for Am, 8 to 20% for Cd, 12 to 16% for Co, 28 to 34% for Se, and 32 to 41% for Zn. Differences in chlorophyll a concentration in ingested natural seston did not have significant impact on the assimilation of Am, Co, Se and Zn. The influx rate of elements from the dissolved phase increased with the dissolved concentration, conforming to Freundlich adsorption isotherms. The calculated dissolved uptake rate constant was greatest for Ag, followed by Zn > Am = Cd > Co > Se. The estimated absorption efficiency from the dissolved phase was 1.53% for Ag, 0.34% for Am, 0.31% for Cd, 0.11% for Co, 0.03% for Se and 0.89% for Zn. Salinity had an inverse effect on the influx rate from the dissolved phase and dissolved organic carbon concentration had no significant effect on trace element uptake. The calculated efflux rate constants for all elements ranged from 1.0 to 3.0% d-1. The route of trace element uptake (food vs dissolved) and the duration of exposure to dissolved trace elements (12 h vs 6 d) did not significantly influence trace element efflux rates. A model which used the experimentally determined influx and efflux rates for each of the trace elements, following exposure from ingested food and from water, predicted concentrations of Ag, Cd, Se and Zn in mussels that were directly comparable to actual tissue concentrations independently measured in the 2

  5. Evolution of active host-attraction strategies in the freshwater mussel tribe Lampsilini (Bivalvia: Unionidae).

    PubMed

    Zanatta, David T; Murphy, Robert W

    2006-10-01

    Most freshwater mussels (Bivalvia: Unionoida) require a host, usually a fish, to complete their life cycle. Most species of mussels show adaptations that increase the chances of glochidia larvae contacting a host. We investigated the evolutionary relationships of the freshwater mussel tribe Lampsilini including 49 of the approximately 100 extant species including 21 of the 24 recognized genera. Mitochondrial DNA sequence data (COI, 16S, and ND1) were used to create a molecular phylogeny for these species. Parsimony and Bayesian likelihood topologies revealed that the use of an active lure arose early in the evolution of the Lampsiline mussels. The mantle flap lure appears to have been the first to evolve with other lure types being derived from this condition. Apparently, lures were lost independently in several clades. Hypotheses are discussed as to how some of these lure strategies may have evolved in response to host fish prey preferences.

  6. Experimental exposure to urban and pink noise affects brain development and song learning in zebra finches (Taenopygia guttata)

    PubMed Central

    Curcio, Michael T.; Swaddle, John P.; MacDougall-Shackleton, Scott A.

    2016-01-01

    Recently, numerous studies have observed changes in bird vocalizations—especially song—in urban habitats. These changes are often interpreted as adaptive, since they increase the active space of the signal in its environment. However, the proximate mechanisms driving cross-generational changes in song are still unknown. We performed a captive experiment to identify whether noise experienced during development affects song learning and the development of song-control brain regions. Zebra finches (Taeniopygia guttata) were bred while exposed, or not exposed, to recorded traffic urban noise (Study 1) or pink noise (Study 2). We recorded the songs of male offspring and compared these to fathers’ songs. We also measured baseline corticosterone and measured the size of song-control brain regions when the males reached adulthood (Study 1 only). While male zebra finches tended to copy syllables accurately from tutors regardless of noise environment, syntax (the ordering of syllables within songs) was incorrectly copied affected by juveniles exposed to noise. Noise did not affect baseline corticosterone, but did affect the size of brain regions associated with song learning: these regions were smaller in males that had been had been exposed to recorded traffic urban noise in early development. These findings provide a possible mechanism by which noise affects behaviour, leading to potential population differences between wild animals occupying noisier urban environments compared with those in quieter habitats. PMID:27602270

  7. Experimental exposure to urban and pink noise affects brain development and song learning in zebra finches (Taenopygia guttata).

    PubMed

    Potvin, Dominique A; Curcio, Michael T; Swaddle, John P; MacDougall-Shackleton, Scott A

    2016-01-01

    Recently, numerous studies have observed changes in bird vocalizations-especially song-in urban habitats. These changes are often interpreted as adaptive, since they increase the active space of the signal in its environment. However, the proximate mechanisms driving cross-generational changes in song are still unknown. We performed a captive experiment to identify whether noise experienced during development affects song learning and the development of song-control brain regions. Zebra finches (Taeniopygia guttata) were bred while exposed, or not exposed, to recorded traffic urban noise (Study 1) or pink noise (Study 2). We recorded the songs of male offspring and compared these to fathers' songs. We also measured baseline corticosterone and measured the size of song-control brain regions when the males reached adulthood (Study 1 only). While male zebra finches tended to copy syllables accurately from tutors regardless of noise environment, syntax (the ordering of syllables within songs) was incorrectly copied affected by juveniles exposed to noise. Noise did not affect baseline corticosterone, but did affect the size of brain regions associated with song learning: these regions were smaller in males that had been had been exposed to recorded traffic urban noise in early development. These findings provide a possible mechanism by which noise affects behaviour, leading to potential population differences between wild animals occupying noisier urban environments compared with those in quieter habitats.

  8. The influence of inherited plumage colour morph on morphometric traits and breeding investment in zebra finches (Taeniopygia guttata).

    PubMed

    Krause, E Tobias; Krüger, Oliver; Hoffman, Joseph I

    2017-01-01

    Melanin-based plumage polymorphism occurs in many wild bird populations and has been linked to fitness variation in several species. These fitness differences often arise as a consequence of variation in traits such as behaviour, immune responsiveness, body size and reproductive investment. However, few studies have controlled for genetic differences between colour morphs that could potentially generate artefactual associations between plumage colouration and trait variation. Here, we used zebra finches (Taeniopygia guttata) as a model system in order to evaluate whether life-history traits such as adult body condition and reproductive investment could be influenced by plumage morph. To maximise any potential differences, we selected wild-type and white plumage morphs, which differ maximally in their extent of melanisation, while using a controlled three-generation breeding design to homogenise the genetic background. We found that F2 adults with white plumage colouration were on average lighter and had poorer body condition than wild-type F2 birds. However, they appeared to compensate for this by reproducing earlier and producing heavier eggs relative to their own body mass. Our study thus reveals differences in morphological and life history traits that could be relevant to fitness variation, although further studies will be required to evaluate fitness effects under natural conditions as well as to characterise any potential fitness costs of compensatory strategies in white zebra finches.

  9. The influence of inherited plumage colour morph on morphometric traits and breeding investment in zebra finches (Taeniopygia guttata)

    PubMed Central

    Krüger, Oliver

    2017-01-01

    Melanin-based plumage polymorphism occurs in many wild bird populations and has been linked to fitness variation in several species. These fitness differences often arise as a consequence of variation in traits such as behaviour, immune responsiveness, body size and reproductive investment. However, few studies have controlled for genetic differences between colour morphs that could potentially generate artefactual associations between plumage colouration and trait variation. Here, we used zebra finches (Taeniopygia guttata) as a model system in order to evaluate whether life-history traits such as adult body condition and reproductive investment could be influenced by plumage morph. To maximise any potential differences, we selected wild-type and white plumage morphs, which differ maximally in their extent of melanisation, while using a controlled three-generation breeding design to homogenise the genetic background. We found that F2 adults with white plumage colouration were on average lighter and had poorer body condition than wild-type F2 birds. However, they appeared to compensate for this by reproducing earlier and producing heavier eggs relative to their own body mass. Our study thus reveals differences in morphological and life history traits that could be relevant to fitness variation, although further studies will be required to evaluate fitness effects under natural conditions as well as to characterise any potential fitness costs of compensatory strategies in white zebra finches. PMID:29190647

  10. Nondestructive detection of zebra chip disease in potatoes using near-infrared spectroscopy

    USDA-ARS?s Scientific Manuscript database

    Near-Infrared (NIR) spectroscopy in the wavelength region from 900 nm to 2600 nm was evaluated as the basis for a rapid, non-destructive method for the detection of Zebra Chip disease in potatoes and the measurement of sugar concentrations in affected tubers. Using stepwise regression in conjunction...

  11. Sex bias and dosage compensation in the zebra finch versus chicken genomes: General and specialized patterns among birds

    PubMed Central

    Itoh, Yuichiro; Replogle, Kirstin; Kim, Yong-Hwan; Wade, Juli; Clayton, David F.; Arnold, Arthur P.

    2010-01-01

    We compared global patterns of gene expression between two bird species, the chicken and zebra finch, with regard to sex bias of autosomal versus Z chromosome genes, dosage compensation, and evolution of sex bias. Both species appear to lack a Z chromosome–wide mechanism of dosage compensation, because both have a similar pattern of significantly higher expression of Z genes in males relative to females. Unlike the chicken Z chromosome, which has female-specific expression of the noncoding RNA MHM (male hypermethylated) and acetylation of histone 4 lysine 16 (H4K16) near MHM, the zebra finch Z chromosome appears to lack the MHM sequence and acetylation of H4K16. The zebra finch also does not show the reduced male-to-female (M:F) ratio of gene expression near MHM similar to that found in the chicken. Although the M:F ratios of Z chromosome gene expression are similar across tissues and ages within each species, they differ between the two species. Z genes showing the greatest species difference in M:F ratio were concentrated near the MHM region of the chicken Z chromosome. This study shows that the zebra finch differs from the chicken because it lacks a specialized region of greater dosage compensation along the Z chromosome, and shows other differences in sex bias. These patterns suggest that different avian taxa may have evolved specific compensatory mechanisms. PMID:20357053

  12. Arthropod parasites of springbok, gemsbok, kudus, giraffes and Burchell's and Hartmann's zebras in the Etosha and Hardap Nature Reserves, Namibia.

    PubMed

    Horak, I G; Anthonissen, M; Krecek, R C; Boomker, J

    1992-12-01

    A total of 48 springbok, 48 gemsbok, 23 kudus and 6 giraffes were examined for ticks and lice, while 9 Burchell's zebras and 6 Hartmann's mountain zebras were examined only for ticks. Springbok and gemsbok were shot in both the Etosha National Park in the north and the Hardap Nature Reserve in the south of Namibia. All the other animals were shot in the Etosha National Park. A total of 7 ixodid tick species and 8 lice species were recovered. The springbok carried few ticks. The adults of a Rhipicephalus sp. (near R. oculatus) were most numerous on the gemsbok, especially during November. The kudus were the only animals harbouring Rhipicephalus zambeziensis. Adult Hyalomma truncatum, followed by adult Hyalomma marginatum rufipes, were most abundant on the giraffes and adult Rhipicephalus evertsi mimeticus were commonest on the zebras.

  13. Specific profiles of perfluorinated compounds in surface and drinking waters and accumulation in mussels, fish, and dolphins from southeastern Brazil.

    PubMed

    Quinete, Natalia; Wu, Qian; Zhang, Tao; Yun, Se Hun; Moreira, Isabel; Kannan, Kurunthachalam

    2009-10-01

    Despite the concern over widespread distribution of perfluorinated compounds (PFCs) even in sparsely populated regions of the world, few studies have reported their occurrence in South America. In this study, PFCs were measured in Rio de Janeiro State in southeast Brazil: in drinking water from various districts in the State, in river water and tucuxi dolphins from the Paraiba do Sul River, several species of fish from the State, and mussels from Guanabara Bay. Liver, kidney, and muscle from fishes were analyzed to enable an understanding of the tissue distribution of PFCs. PFOS, PFOA, and PFHxS were detected in all drinking water samples in concentration ranges of 0.58-6.70, 0.35-2.82, and 0.15-1.00 ng L(-1), respectively. The profiles of PFCs in drinking water from Brazil (with PFOS concentrations comparable to or higher than those of PFOA) were different from the profiles that have been reported for other countries. In fish, concentrations of PFOS were, in general, higher in liver than in muscle. Concentrations of PFOA in livers of fish were similar to or lower than fish muscle tissue concentrations. PFOS and PFOA were found in brown mussels from Guanabara Bay. Bioconcentration factors (BCFs) of PFOA calculated for mussels were higher than the BCFs calculated for fishes. Elevated concentrations of PFUnDA (mean: 109+/-17.4 ng g(-1) wet weight) were found in mussels from certain locations within Guanabara Bay. Although PFCs were detected in all types of samples analyzed, the concentrations were generally lower than the concentrations reported for Japan and the USA.

  14. Immune Response in Mussels To Environmental Pollution.

    ERIC Educational Resources Information Center

    Pryor, Stephen C.; Facher, Evan

    1997-01-01

    Describes the use of mussels in measuring the extent of chemical contamination and its variation in different coastal regions. Presents an experiment to introduce students to immune response and the effects of environmental pollution on marine organisms. Contains 14 references. (JRH)

  15. A cohort of new adhesive proteins identified from transcriptomic analysis of mussel foot glands.

    PubMed

    DeMartini, Daniel G; Errico, John M; Sjoestroem, Sebastian; Fenster, April; Waite, J Herbert

    2017-06-01

    The adaptive attachment of marine mussels to a wide range of substrates in a high-energy, saline environment has been explored for decades and is a significant driver of bioinspired wet adhesion research. Mussel attachment relies on a fibrous holdfast known as the byssus, which is made by a specialized appendage called the foot. Multiple adhesive and structural proteins are rapidly synthesized, secreted and moulded by the foot into holdfast threads. About 10 well-characterized proteins, namely the mussel foot proteins (Mfps), the preCols and the thread matrix proteins, are reported as representing the bulk of these structures. To explore how robust this proposition is, we sequenced the transcriptome of the glandular tissues that produce and secrete the various holdfast components using next-generation sequencing methods. Surprisingly, we found around 15 highly expressed genes that have not previously been characterized, but bear key similarities to the previously defined mussel foot proteins, suggesting additional contribution to byssal function. We verified the validity of these transcripts by polymerase chain reaction, cloning and Sanger sequencing as well as confirming their presence as proteins in the byssus. These newly identified proteins greatly expand the palette of mussel holdfast biochemistry and provide new targets for investigation into bioinspired wet adhesion. © 2017 The Author(s).

  16. Bioadhesion of mussels and geckos: Molecular mechanics, surface chemistry, and nanoadhesives

    NASA Astrophysics Data System (ADS)

    Lee, Haeshin

    The adhesive strategies of living creatures are diverse, ranging from temporary to permanent adhesions with various functions such as locomotion, self-defense, communication, colony formation, and so on. The classic example of temporary adhesion is the gecko, which is known for its ability to walk along vertical and even inverted surfaces; this remarkable adhesion arises from the interfacial weak interactions of van der Waals and capillary forces. In contrast, a celerbrated example of permanent adhesion is found in marine mussels which secrete protein adhesives that function in aqueous environments without mechanical failure against turbulent conditions on the seashore. In addition, mussel adhesives stick to virtually all inorganic and organic surfaces. However, most commonly used man-made adhesives lack such unique adhesion properties compared to their natural counterparts. For example, many commercial adhesives quickly lose their adhesive strength when exposed to solvents, particularly water. The first part of this thesis focused on adhesion mechanics of mussels at a single-molecule level, in which the adhesive molecule showed surprisingly strong yet reversible adhesion on inorganic surfaces but exhibited irreversible covalent bond formation on organic surfaces. Strong and reversible adhesion on mucin surfaces was found, indicating potential application for drug delivery via mucus layers. Next, inspired by the mussel's versatile adhesion on a wide variety of material surfaces, a material-independent surface modification chemistry called 'polydopamine coating' is described. This concept was subsequently adapted to develop a surface-independent polymeric primer for layer-by-layer assembly of multifunctional coatings. Finally, a new bio-hybrid adhesive 'geckel' was developed by the functional combination of adhesion strategies of geckos and mussels. The new bio-inspired adhesive and material-independent surface chemistry can revolutionize the research areas such as

  17. Sensor data as a measure of native freshwater mussel impact on nitrate formation and food digestion in continuous-flow mesocosms

    USGS Publications Warehouse

    Bril, Jeremy S.; Durst, Jonathan J.; Hurley, Brion M.; Just, Craig L.; Newton, Teresa J.

    2014-01-01

    Native freshwater mussels can influence the aquatic N cycle, but the mechanisms and magnitude of this effect are not fully understood. We assessed the effects of Amblema plicata and Lampsilis cardium on N transformations over 72 d in 4 continuous-flow mesocosms, with 2 replicates of 2 treatments (mesocosms with and without mussels), equipped with electronic water-chemistry sensors. We compared sensor data to discrete sample data to assess the effect of additional sensor measurements on the ability to detect mussel-related effects on NO3– formation. Analysis of 624 sensor-based data points detected a nearly 6% increase in NO3– concentration in overlying water of mesocosms with mussels relative to mesocosms without mussels (p 3– between treatments. Mussels also significantly increased NO2– concentrations in the overlying water, but no significant difference in total N was observed. We used the sensor data for phytoplankton-N and NH4+ to infer that digestion times in mussels were 13 ± 6 h. The results suggest that rapid increases in phytoplankton-N levels in the overlying water can lead to decreased lag times between phytoplankton-N and NH4+ maxima. This result indicates that mussels may adjust their digestion rates in response to increased levels of food. The adjustment in digestion time suggests that mussels have a strong response to food availability that can disrupt typical circadian rhythms. Use of sensor data to measure directly and to infer mussel effects on aquatic N transformations at the mesocosm scale could be useful at larger scales in the future.

  18. Using Digital Images of the Zebra Finch Song System as a Tool to Teach Organizational Effects of Steroid Hormones: A Free Downloadable Module

    ERIC Educational Resources Information Center

    Grisham, William; Schottler, Natalie A.; Beck McCauley, Lisa M.; Pham, Anh P.; Ruiz, Maureen L.; Fong, Michelle C.; Cui, Xinran

    2011-01-01

    Zebra finch song behavior is sexually dimorphic: males sing and females do not. The neural system underlying this behavior is sexually dimorphic, and this sex difference is easy to quantify. During development, the zebra finch song system can be altered by steroid hormones, specifically estradiol, which actually masculinizes it. Because of the…

  19. Zebra: An advanced PWR lattice code

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Cao, L.; Wu, H.; Zheng, Y.

    2012-07-01

    This paper presents an overview of an advanced PWR lattice code ZEBRA developed at NECP laboratory in Xi'an Jiaotong Univ.. The multi-group cross-section library is generated from the ENDF/B-VII library by NJOY and the 361-group SHEM structure is employed. The resonance calculation module is developed based on sub-group method. The transport solver is Auto-MOC code, which is a self-developed code based on the Method of Characteristic and the customization of AutoCAD software. The whole code is well organized in a modular software structure. Some numerical results during the validation of the code demonstrate that this code has a good precisionmore » and a high efficiency. (authors)« less

  20. Incidence and Management Costs of Freshwater Aquatic Nuisance Species at Projects Operated by the U.S. Army Corps of Engineers

    DTIC Science & Technology

    2010-07-01

    the occurrence of ANS impacts (Yes or No) from freshwater algae, large aquatic plants, fish, zebra mussels, Asiatic clams, water fleas, crayfish...2005. Freshwater aquatic nuisance species impacts and management costs and benefits at federal water resources projects. ERDC/TN ANSRP-06-3...ER D C/ EL T R- 10 -1 3 Aquatic Nuisance Species Research Program Incidence and Management Costs of Freshwater Aquatic Nuisance Species