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Sample records for danish blue mussels

  1. Levels of hydrocarbons in mussels, Mytilus edulis, and surface sediments from Danish coastal areas

    SciTech Connect

    Jensen, K.

    1981-02-01

    Until recently, most effort in oil pollution research has been spent on investigating the effects of oil spills and use of detergents. The effects of long-term low level input to the marine environment are much less elucidated. This study represents the first step in a project concerning chronic oil pollution undertaken by the Marine Pollution Laboratory, Denmark. Results from previous studies on this subject in the area concerned, which have not been internationally published, are also included. In a series of Danish coastal localities, samples of surface sediments (top cm) were taken and samples of blue mussels, Mytilus edulis, were collected by SCUBA diving.

  2. Predator-prey interactions between blue crabs and ribbed mussels living in clumps

    NASA Astrophysics Data System (ADS)

    Lin, Junda

    1991-01-01

    Predator-prey interactions between blue crabs ( Callinectes sapidus) and ribbed mussels ( Geukensia demissa) were studied by manipulating different components of mussel clump structure in the laboratory to test their effects on the mussels' susceptibility to crab predation. Mussels with stronger attachment strength or those buried deeper in the sediment suffered lower mortality. Blue crabs showed no significant size selectivity when two size classes of mussles (30-40 and 50-60 mm in shell heights) were offered. When juvenile mussels were attached to adult conspecifics and completely buried in the centres of clumps as in the field, blue crabs did not actively search for them. The crabs, however, did consume juveniles as by-products when they preyed upon the adult mussels to which the juveniles were attached.

  3. The Edible Blue Mussel: A Learning Experience for Marine Education. Northern New England Marine Education Project.

    ERIC Educational Resources Information Center

    Maine Univ., Orono. Coll. of Education.

    The major unifying concept for each of the disciplinary sections in this curriculum infusion unit is that the blue mussel is an easily obtainable, high quality, very palatable seafood. A section is provided for teacher familiarity with the anatomy and ecological background of the mussel. The guide is arranged by discipline areas. Sections provide…

  4. BIOACCUMULATION OF PCB CONGENERS BY BLUE MUSSELS DEPLOYED IN NEW BEDFORD HARBOR, MA

    EPA Science Inventory

    Blue mussels (Mytilus edulis) were deployed to monitor the levels of bioavailable contaminants during a pilot dredging project in New Bedford Harbor (NBH), Massachusetts. issolved and particulate seawater samples also were collected periodically during these deployments. olychlor...

  5. UPTAKE AND DEPURATION OF ORGANIC CONTAMINANTS BY BLUE MUSSELS (MYTILUS EDULIS) EXPOSED TO ENVIRONMENTALLY CONTAMINATED SEDIMENT

    EPA Science Inventory

    Experiments were designed to expose blue mussels (Mytilus edulis) to contaminated sediment collected from Narragansett Bay, Rhode Island, USA in 1982. Measurements were taken to allow comparisons of the uptake and depuration of polycyclic aromatic hydrocarbons (PAHs) and polychlo...

  6. Bioaccumulation of metals by blue mussel (Mytilus edulis) deployed in New Bedford Harbor, Massachusetts

    SciTech Connect

    McGovern, D.G.; Bergen, B.J.; Nelson, W.G.

    1995-12-31

    As part of a marine Superfund site remedial monitoring program, blue mussels, Mytilus edulis, were deployed for 28 day intervals to monitor the levels of bioavailable copper, cadmium, lead, nickel and zinc in New Bedford Harbor, Massachusetts. Dissolved and particulate seawater samples were collected periodically during twelve separate deployments and analyzed for these metals also. Bioconcentration factors, the concentration in mussel tissue normalized to dissolved, particulate and total seawater concentrations, were calculated. Previous studies conducted at this site demonstrated that these six metals bioconcentrate in blue mussels and that bioaccumulation patterns vary for each metal. The sources of this variability are discussed with respect to the partitioning of each metal in seawater.

  7. Cloning and expression of recombinant adhesive protein MEFP-2 of the blue mussel, Mytilus edulis

    DOEpatents

    Silverman, Heather G.; Roberto, Francisco F.

    2006-02-07

    The present invention includes a Mytilus edulis cDNA having a nucleotide sequence that encodes for the Mytilus edulis foot protein-2 (Mefp-2), an example of a mollusk foot protein. Mefp-2 is an integral component of the blue mussels' adhesive protein complex, which allows the mussel to attach to objects underwater. The isolation, purification and sequencing of the Mefp-2 gene will allow researchers to produce Mefp-2 protein using genetic engineering techniques. The discovery of Mefp-2 gene sequences will also allow scientists to better understand how the blue mussel creates its waterproof adhesive protein complex.

  8. Cloning and expression of recombinant adhesive protein Mefp-1 of the blue mussel, Mytilus edulis

    DOEpatents

    Silverman, Heather G.; Roberto, Francisco F.

    2006-01-17

    The present invention comprises a Mytilus edulis cDNA sequenc having a nucleotide sequence that encodes for the Mytilus edulis foot protein-1 (Mefp-1), an example of a mollusk foot protein. Mefp-1 is an integral component of the blue mussels' adhesive protein complex, which allows the mussel to attach to objects underwater. The isolation, purification and sequencing of the Mefp-1 gene will allow researchers to produce Mefp-1 protein using genetic engineering techniques. The discovery of Mefp-1 gene sequence will also allow scientists to better understand how the blue mussel creates its waterproof adhesive protein complex.

  9. Mussel fishery affects diet and reduces body condition of Eiders Somateria mollissima in the Wadden Sea

    NASA Astrophysics Data System (ADS)

    Laursen, Karsten; Asferg, Karen S.; Frikke, John; Sunde, Peter

    2009-06-01

    Although the Danish Wadden Sea is of international importance for several bird species, large-scale blue mussel Mytilus edulis fishing took place from 1984-1987, ceasing thereafter due to low mussel stocks. Mussel fishing removes much of the blue mussel biomass, especially larger individuals. Hence we predict that intensive mussel fishing will affect their predators, such as the Eider Somateria mollissima, which is predominantly a blue mussel feeder by, 1) reducing the amount of blue mussels in their diet relative to alternative prey items, 2) exploitation of smaller blue mussel shell classes, 3) loss of body condition, 4) changing feeding distribution to aggregate to the remaining mussel stocks, and 5) decreasing numbers. Before winter 1986/87 blue mussel biomass was estimated at 40,600 tons, decreasing to 15,400 tons in 1987/88 due to mussel fishery. We collected Eiders in both periods to monitor their diet and body mass and used aerial surveys to determine changes in numbers and distribution. Between the two periods, blue mussels declined in the Eiders diet, numbers of Eiders with empty stomachs increased and the mean length of blue mussel taken by Eiders decreased. Eider body condition declined from 1986/87 to 1987/88, mostly the result of the reduction in numbers of individuals with blue mussel remains in their gizzards and in better body condition compared to those taking alternative food items or having empty gizzards. Eiders shifted their distribution from the southern part of the Danish Wadden Sea to the northern part, where the remaining blue mussel stocks were situated. Eider numbers were lowest in 1987/88, the year of lowest blue mussel stocks. We conclude that intensive mussel fishery affected the Eider's diet, reduced their body condition and affected distribution and abundance. The results also showed that availability of blue mussels may have a key role in building up and maintaining body condition in Eiders during winter.

  10. [BIOCHEMICAL RESPONSE OF BLUE MUSSELS MYTILUS EDULIS L. FROM THE WHITE SEA TO RAPID TEMPERATURE CHANGES].

    PubMed

    Fokina, N N; Lysenko, L A; Sukhovskaya, I V; Vdovichenko, E A; Borvinskaya, E V; Kantserova, N P; Krupnova, M Yu; Ruokolainen, T R; Smirnov, L P; Vysotskaya, R U; Bakhmet, I N; Nemova, N N

    2015-01-01

    The effect of a rapid temperature change on the biochemical status of blue mussels Mytilus edulis L. from the White Sea was studied under conditions of aquarium experiment. It is shown that modifications of the composition of reserve and structural lipids and their fatty acids, of the activity of lysosomal enzymes (β-glucosidases, cathepsins B and D), of calcium-dependent proteases of cytocol (calpains) and of the enzyme of the second phase of biotransformation of xenobiotics - glutathione-S-transferase, reflect an unspecific compensatory reaction of bivalves to stress action of environmental factors and indicate reconstruction of blue mussel metabolism as early as within first hours of temperature change. The initial high level of glutathione-S-transferase activity in control blue mussels as well as an increase of glutathione concentration in the course of experiment may facilitate successful exit of mussels from the state of reduced metabolism. PMID:26856072

  11. Comparison of PCB and trace metal bioaccumulation in the blue mussel, Mytilus edulis, and the ribbed mussel, Modiolus demissus, in New Bedford Harbor, Massachusetts

    SciTech Connect

    Nelson, W.G.; Bergen, B.J.; Cobb, D.J.

    1995-03-01

    The accumulation of PCBs and trace metals was compared at 14-d intervals between two filter-feeding bivalves, the blue mussel, Mytilus edulis, and the ribbed mussel, Modiolus demissus, after deployment in New Bedford Harbor, Massachusetts, for up to 56 d. Contaminant uptake in deployed organisms also was compared with indigenous ribbed mussels. Significant mortality occurred in blue mussels after 28 d, when water temperatures exceeded 25 C. Therefore, tissue-residue comparisons between species are presented only up to day 28, while those between deployed and indigenous ribbed mussels continue to day 56. Results indicated that total PCB tissue residues and congener distributions were not statistically different in the two mussel species on day 28. Total PCB concentrations in both deployed mussel species reached approximately 30 {mu}g g{sup {minus}1} dry weight by day 28. Additionally, total PCB concentrations and congener distributions in the deployed ribbed mussels were not statistically different from the indigenous ribbed mussels on day 28, demonstrating that steady state was attained within 28 d. With respect to metal uptake, no single accumulation pattern occurred for the eight metals quantified. After 28 d, lead, cadmium, and iron concentrations in deployed blue and ribbed mussels were statistically similar. However, nickel and zinc accumulations were significantly greater in the blue mussels, and copper, chromium, and manganese were accumulated to significantly higher concentrations in the ribbed mussels. The comparison between the ribbed mussels indicated that cadmium and lead concentrations were significantly higher in indigenous than in deployed mussels after 28 d.

  12. Comparative study of predatory responses in blue mussels ( Mytilus edulis L.) produced in suspended long line cultures or collected from natural bottom mussel beds

    NASA Astrophysics Data System (ADS)

    Christensen, Helle Torp; Dolmer, Per; Petersen, Jens Kjerulf; Tørring, Ditte

    2012-03-01

    Blue mussels ( Mytilus edulis L.) are a valuable resource for commercial shellfish production and may also have uses as a tool in habitat improvement, because mussel beds can increase habitat diversity and complexity. A prerequisite for both commercial mussel production and habitat improvement is the availability of seed mussels collected with minimum impact on the benthic ecosystem. To examine whether mussels collected in suspended cultures can be used for bottom culture production and as tool in habitat improvement, the differences in predatory defence responses between suspended and bottom mussels exposed to the predatory shore crab ( Carcinus maenas L.) were tested in laboratory experiments and in the field. Predatory defence responses (byssal attachment and aggregation) and morphological traits were tested in laboratory, while growth and mortality were examined in field experiments. Suspended mussels had an active response in relation to the predator by developing a significantly firmer attachment to the substrate and a closer aggregated structure. Bottom mussels had a passive strategy by having a thicker shell and larger relative size of the adductor muscle. In a field experiment mussels originated from suspended cultures had a higher length increment and lower mortality when compared to bottom mussels. It is concluded that suspended mussels potentially are an alternative resource to bottom culture and can be used in habitat improvement of mussel beds, but that the use of suspended mussels has to be tested further in large-scale field experiments.

  13. Heavy metals in blue mussels (mytilus edulis) in the Bergen Harbor area, Western Norway

    SciTech Connect

    Andersen, V.; Johannessen, P.J.; Maage, A.

    1996-12-31

    Heavy metal discharges to the marine environment are of great concern all over the world. Both essential (e.g., Fe, Zn, Cu) and non essential (e.g., Hg, Cd, Pb) metals are toxic to living organism when subjected to high concentration. Many heavy metals accumulate in organisms and some also accumulate in the food chain. The anthropogenic heavy metal outlets can in this way both reduce marine species diversity and ecosystem. Further, by consuming seafood, humans will be exposed to the metals with a potential danger to human health. Goldberg proposed to use marine mussels to monitor contamination levels of coastal waters. Since then marine mussels, especially the blue mussel (Mytilus edulis), has been used widely as a surveillance organism. The blue mussel is regarded a suitable species for this purpose because it accumulates metals, it sessile, has a relatively long life span, is large enough for individual analysis, can tolerate a relatively wide range of temperature and salinity regimes, and can also synthesize the metal-binding protein, metallothionein, for metal detoxification. Furthermore, the blue mussel is a popular and tasteful food source and is suitable for culturing. The world-wide annual yield of mussels during the period 1988 to 1992 was about 1.3 million tons, of which about 0.5 million tons was Mytilus edulis. In Norway, the annual production was 77 tons in 1990. The interest of culturing mussels has increased in recent years, but the consumption of mussels has been hampered both by toxic algae and high levels of heavy metals. The latter is of special concern to those close to urban or industrial areas. This study investigated whether blue mussels in the Bergen Harbor area were contaminated with the heavy metals zinc, copper, lead, cadmium, and mercury, evaluating whether humans could eat them. 21 refs., 6 figs.

  14. Modeling the Role of Zebra Mussels in the Proliferation of Blue-green Algae in Saginaw Bay, Lake Huron

    EPA Science Inventory

    Under model assumptions from Saginaw Bay 1991, selective rejection of blue-green algae by zebra mussels appears to be a necessary factor in the enhancement of blue-green algae production in the presence of zebra mussels. Enhancement also appears to depend on the increased sedime...

  15. COMPARISON OF PCB AND TRACE METAL BIOACCUMULATION IN THE BLUE MUSSEL, MYTILUS EDULIS, AND THE RIBBED MUSSEL, MODIOLUS DEMISSUS, IN NEW BEDFORD HARBOR, MASSACHUSETTS

    EPA Science Inventory

    The accumulation of PCBs and trace metals was compared at 14-d intervals between two filter-feeding bivalves, the blue mussel, Mytilus edulis, and the ribbed mussel, Modiolus demissus, after deployment in New Bedford Harbor, Massachusetts, for up to 56 d. Contaminant uptake in de...

  16. Numerical modelling of blue mussel (Mytilus edulis) bacterial contamination

    NASA Astrophysics Data System (ADS)

    Dabrowski, Tomasz; Doré, William J.; Lyons, Kieran; Nolan, Glenn D.

    2014-05-01

    Bivalve shellfish such as oysters and mussels can concentrate human pathogens when grown in areas impacted by municipal wastewater. Under EU regulation this risk to consumers is controlled by determining the sanitary quality of bivalve shellfish production areas based on the concentration of Escherichia coli present in shellfish flesh. The authors present a modelling approach to simulate an uptake of E. coli from seawater and subsequent depuration by Mytilus edulis. The model that dynamically predicts E. coli concentration in the mussel tissue is embedded within a 3-D numerical modelling system comprising hydrodynamic, biogeochemical, shellfish ecophysiological and the newly proposed microbial modules. The microbial module has two state variables, namely, the concentrations of E. coli in water and in the mussel tissue. Novel formulations to calculate the filtration rates by mussels and the resulting uptake of bacteria are proposed; these rates are updated at every computational time step. Concentrations of E. coli in seawater are also updated accordingly taking into account the amounts ingested by mussels. The model has been applied to Bantry Bay in the south-west of Ireland. The results indicate that the model is capable of reproducing the official classification of shellfish waters in the bay based on monthly sampling at several stations. The predicted filtration rates and ratios of E. coli in water and mussels also compare well with the literature. The model thus forms a tool that may be used to assist in the classification of shellfish waters at much greater spatial and temporal detail than that offered by a field monitoring programme. Moreover, it can also aid in designing an efficient monitoring programme. The model can also be utilised to determine the contribution of individual point sources of pollution on the microbial loading in mussels and, when incorporated into an operational framework, it can provide a short-term forecasting of microbial

  17. Growth of juvenile blue mussels (Mytilus edulis) on suspended collectors in the Dutch Wadden Sea

    NASA Astrophysics Data System (ADS)

    Jacobs, P.; Beauchemin, C.; Riegman, R.

    2014-01-01

    In The Netherlands, fishing for juvenile blue mussels (Mytilus edulis) on wild beds is gradually replaced by harvesting of seeds from suspended collectors. Both the relaxation of fishing as well as the up-scaling of the number of seed collectors are expected to result in an increase in the number of mussels in the Wadden Sea. Consequently, an enhanced mussel population will cause an additional filtration impact on the system. The question is raised to what extent collectors can be used without negatively affecting the carrying capacity of an ecosystem. Therefore, a monitoring programme was initiated to study the growth of juvenile mussels on suspended collectors. This growth was related to food availability, measured as chlorophyll-a, and temperature both before and after settlement. Findings will serve as input for mathematical models predicting the carrying capacity for mussel seed collectors in this area. The results for 2010 and 2011 are presented. In 2011 settled mussels achieved a higher growth rate, while phytoplankton concentrations after settlement were lower. This contradicts the general agreement that higher phytoplankton concentrations result in higher growth rates. A positive relation between chlorophyll-a concentrations during the larval period and the growth rate of settled mussels was found. The number of settled larvae was higher in 2011. Results from existing studies on settlement and recruitment on tidal flats combined with estimated settlement date in the current study led to the hypothesis that the number of settled mussels on rope collectors is inversely related to the duration of the larval period (determined by water temperature). Our results indicated that in the Wadden Sea, the intra-annual differences in chlorophyll-a and temperature did not have an impact on the juvenile growth rate, while the interannual differences did. This is an indication that the larval stage is strongly discriminative in terms of juvenile growth rates. Modelling

  18. Bioaccumulation of PCB congeners by blue mussels (Mytilus edulis) deployed in New Bedford Harbor, Massachusetts

    SciTech Connect

    Bergen, B.J. . Environmental Research Lab., Science Applications International Corp.); Nelson, W.G.; Pruell, R.J. . Environmental Research Lab.)

    1993-09-01

    Blue mussels (Mytilus edulis) were deployed to monitor the levels of bioavailable contaminants during a pilot dredging project in New Bedford Harbor (NBH), Massachusetts. Dissolved and particulate seawater samples also were collected periodically during these deployments. Polychlorinated biphenyl (PCB) congener concentrations in both mussel tissue and seawater samples were among the quantified contaminants. Large differences in the dissolved and particulate PCB concentrations in seawater and tissue residue concentrations in mussels were observed along a gradient from the upper harbor to Buzzards Bay. Bioconcentration factors (BCFs) were calculated for six PCB congenors at two stations in NBH and a reference site in Buzzards Bay. Equations were generated relating the log BCF to the log octanol/water partition coefficient (K[sub ow]) for these congeners. A consistent relationship was found between dissolved PCB congener concentrations and tissue concentrations in the mussels. This study demonstrates the utility of the blue mussel as a monitoring organism for quantifying bioavailable contaminants in seawater and for relating PCB tissue residues with seawater concentrations.

  19. USE OF THE BLUE MUSSEL, MYTILUS EDULIS, IN WATER QUALITY TOXICITY TESTING AND IN SITU MARINE BIOLOGICAL MONITORING

    EPA Science Inventory

    An effort was undertaken at the Environmental Protection Agency's (EPA) Environmental Research Laboratory, Narragansett (ERL-N),Rhode Island, to evaluate the integration of in situ biological monitoring with the blue mussel, Mytilus edulis L. into EPA's Complex Effluent Toxicity ...

  20. Metabolism of pectenotoxins in brown crabs Cancer pagurus fed with blue mussels Mytilus edulis

    NASA Astrophysics Data System (ADS)

    Li, Zhaoxin

    2009-09-01

    We investigated the metabolism of pectenotoxins in brown crabs ( Cancer pagurus). The crabs were fed with blue mussels ( Mytilus edulis) for 21 d then depurated for 42 d. We extracted the toxins from the digestive glands of contaminated crabs, uncontaminated crabs (control group), and the meat of blue mussels using methanol. Extracts of the crab digestive glands were fractionated by liquid-liquid partitioning and solid phase extraction. The fractions were analyzed by liquid chromatography coupled with tandem mass spectrometry (LC-MS/MS) and liquid chromatography coupled with ion-trap mass spectrometry (LC-MSn). We detected a new PTX-like compound, designated as metabolite-1. The MS2 mass spectrum of the metabolite-1 [M+Na]+ ion at m/z 897.5 revealed fragment ions at m/z 853.5 and 555.5, typical of those exhibited by other pectenotoxins.

  1. 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.

  2. Seasonal variations of hydroxylated and methoxylated brominated diphenyl ethers in blue mussels from the Baltic Sea.

    PubMed

    Löfstrand, Karin; Liu, Xitao; Lindqvist, Dennis; Jensen, Sören; Asplund, Lillemor

    2011-07-01

    Hydroxylated polybrominated diphenyl ethers (OH-PBDEs) and methoxylated polybrominated diphenyl ethers (MeO-PBDEs) found at high levels in the Baltic biota are mainly natural products, but can also be formed through metabolism or abiotic oxidation of polybrominated diphenyl ethers (PBDEs). The formation of OH-PBDEs is of concern since there is growing evidence of phenolic toxicity. This study investigates seasonal variations in levels of OH-PBDEs and MeO-PBDEs, focusing on an exposed species, the blue mussel (Mytilus edulis), sampled in the Baltic Sea in May, June, August and October of 2008. Both the OH-PBDE and MeO-PBDE levels in the mussels showed seasonal variations from May to October, the highest concentration of each congener appearing in June. The seasonal variation was more marked for OH-PBDEs than in MeO-PBDEs, but all congeners showed the same trends, except 6-MeO-BDE47 and 2'-MeO-BDE68, which did not significantly decline in concentrations after June. Biotic or abiotic debromination is suggested as a possible reason for the rapid decrease in methoxylated penta- and hexa-BDE concentrations observed in blue mussels from June to August, while the tetraBDE concentrations were stable. In addition, 1,3,7/1,3,8-tribrominated dibenzo-p-dioxins showed the same seasonal variation. The seasonal variations indicates natural formation and are unlikely to be due to transformation of anthropogenic precursors. The levels of PBDEs were fairly constant over time and considerably lower than those of the OH-PBDEs and MeO-PBDEs. The timing of the peaks in concentrations suggests that filamentous macro-algae may be important sources of these compounds found in the blue mussels from this Baltic Sea location. PMID:21288551

  3. Efficiencies of polychlorinated biphenyl assimilation from water and algal food by the blue mussel (Mytilus edulis)

    SciTech Connect

    Bjoerk, M.; Gilek, M.

    1999-04-01

    A novel method was used to estimate assimilation efficiencies (AEs) of dissolved and food associated PCBs (IUPAC 31, 49, and 153) by the Baltic Sea blue mussel (Mytilus edulis). Mussels were exposed to radiolabeled PCBs in a series of short-term toxicokinetic experiments at different algal food concentrations, both at apparent steady-state (ASS) and non-steady-state (NSS) conditions in respect to PCB partitioning between water and algae. The PCB AEs were calculated using a physiologically based bioaccumulation model where experimentally determined uptake and exposure rates at ASS and NSS conditions were combined into linear equation systems, which were solved for PCB AE from water and food. A positive relationship between PCB uptake and algae clearance by the mussels was observed for all three PCBs. The PCB AEs from both water and food increased with congener hydrophobicity (octanol/water partition coefficient [K{sub ow}]), but AEs decreased with increases in water pumping and filtration rate of the mussels, respectively. The average contribution of food-associated PCB to the total uptake also increased with K{sub ow} from approximately 30% for PCB 31 and PCB 49 to 50% for PCB 153, mainly as a consequence of increased sorption to the algal food.

  4. Bioaccumulation kinetics of brominated flame retardants (polybrominated diphenyl ethers) in blue mussels (Mytilus edulis)

    SciTech Connect

    Gustafsson, K.; Bjoerk, M.; Burreau, S.; Gilek, M. )

    1999-06-01

    Baltic Sea blue mussels, Mytilus edulis, were exposed to polybrominated diphenyl ethers (PBDEs, IUPAC congeners 47, 99, and 153) and polychlorinated biphenyls (PCBs, congeners 31, 52, 77, 118, and 153) in a flow-through experimental setup for 44 d. After the exposure phase, the mussels were allowed to depurate in natural brackish water for 26 d. After analyses, uptake clearance rate coefficients (k[sub u]), depuration rate coefficients (k[sub d]), and bioaccumulation factors (BAF) were calculated. A rapid uptake of all PBDEs and PCBs was observed, especially for PBDE congeners 47 and 99. The depuration rate decreased with increasing hydrophobicity as expected for the PCBs, but for the PBDEs, depuration rate coefficients appeared to be of the same magnitude for all three congeners independently of log K[sub OW]. The BAFs obtained for PBDE 47 and PBDE 99 were higher than for all other substances in the study, severalfold higher than for PCBs of similar hydrophobicity. The presented data indicate that the bioaccumulation potential of PBDEs, extensively used as flame retardants, is similar or higher than that of PCBs for filter feeding organisms such as blue mussels.

  5. Levels of organochlorine compounds in the Mediterranean blue mussel from the Adriatic Sea.

    PubMed

    Kozul, Darija; Romanić, Snjezana Herceg; Kljaković-Gaspić, Zorana; Veza, Jere

    2009-12-01

    The distribution of polychlorinated biphenyls (PCBs) and organochlorine pesticides (OCPs) was investigated in Mediterranean blue mussel collected at four locations in Mali Ston Bay few times a year in 2005–2007. OCPs were found in all samples and levels ranged between 0.07 and 7.58 ng g−1 dry wt. Levels of PCBs ranged between 0 (below detection limit) and 21.55 ng g−1 dry wt. For most analyzed compounds there were no significant level changes between the 3 years. Exceptions are decreased levels of β-HCH, DDD, and PCB-138 and increased levels of γ-HCH and DDT in 2007. However, mussels from this area are applicable for human diet. PMID:19626261

  6. Effect of starvation on trace metal levels in blue mussels (Mytilus edulis)

    SciTech Connect

    Chou, C.L.; Uthe, J.F. )

    1991-03-01

    The use of bivalves as monitors of marine coastal contamination has become widespread. However, many investigations have shown that numerous factors affect contaminant concentrations, in particular trace metals, in mussels tissues. This is not surprising since some metals, e.g., copper and zinc, have well-established physiological roles, while others, such as cadmium, are toxic to higher animals and have no known physiological function. An organism can serve as a quantitative indicator of environmental contamination only if a tissue contaminant concentration or burden reflects the contamination of the animal's environment in a rational way. The authors have investigated the effect of starvation on a number of trace elements in blue mussels (mytilus edulis) to determine which elements were not eliminated as the animal starved (a burden control model) and which elements were excreted (a concentration control model) in response to decreasing tissue weight.

  7. Seasonal and geographical variations in the biochemical composition of the blue mussel (Mytilus edulis L.) from Ireland.

    PubMed

    Fernández, Ayoa; Grienke, Ulrike; Soler-Vila, Anna; Guihéneuf, Freddy; Stengel, Dagmar B; Tasdemir, Deniz

    2015-06-15

    Blue mussel (Mytilus edulis L.) farming constitutes the largest volume of the shellfish sector in Ireland. Recently, interest in mussel dietary supplements and functional foods has increased significantly. To identify the optimal harvesting time and location in Ireland, blue mussels were investigated for their biochemical composition over a period of one year. The study included samples from aquaculture facilities, wild grown mussels and waste material. Each sample was analysed at four time points to determine the total content of (i) glycogen, (ii) lipids, (iii) proteins, (iv) inorganic substances, and (v) energy. Moreover, fatty acid profiles were investigated by GC-FID revealing high contents of PUFAs and a high ω-3/ω-6 ratio. Compared to less pronounced geographical variations, distinct seasonal trends could be observed for all samples. The content of the investigated metabolite classes, inorganic substances, and energy was at a maximum level in spring or late summer. PMID:25660856

  8. Local effects of blue mussels around turbine foundations in an ecosystem model of Nysted off-shore wind farm, Denmark

    NASA Astrophysics Data System (ADS)

    Maar, Marie; Bolding, Karsten; Petersen, Jens Kjerulf; Hansen, Jørgen L. S.; Timmermann, Karen

    2009-08-01

    The development of off-shore wind farms along the coastline of north-west Europe is rapidly increasing; it is therefore important to study how this will affect the marine environment. The present study modelled the growth and feed-backs of blue mussels in natural beds and on turbine foundations in an off-shore wind farm (OWF) located in a shallow coastal ecosystem by coupling a dynamic energy budget (DEB) model to a small-scale 3D hydrodynamic-biogeochemical model. The model results showed that blue mussels located higher up in the water column on turbine pillars achieved a 7-18 times higher biomass than those located on the scour protection because the former experience an enhanced advective food supply. Secondly, the high biomasses of blue mussels on foundations created local 'hot spots' of biological activity and changed ecosystem dynamics due to their feed-backs e.g. ingestion of microplankton and copepods, excretion of ammonium and egestion of faecal pellets. The model results were supported by field measurements around foundations of Chl a concentrations and biomasses of the fauna community. Our study emphasised that OWFs seem to be particularly favourable for blue mussels in the western Baltic Sea and that the functioning of the OWFs as artificial reef ecosystems depends upon how the blue mussels interact with their local pelagic and benthic environment.

  9. Dominance of blue mussels versus consumer-mediated enhancement of benthic diversity

    NASA Astrophysics Data System (ADS)

    Enderlein, Peter; Wahl, Martin

    2004-03-01

    In the shallow subtidal of Kiel Fjord (western Baltic Sea), the blue mussel Mytilus edulis is the dominant competitor for space. Vertically suspended settlement substrata in the upper 6 m of the water column almost invariably become dominated by M. edulis within a few summer months. However, not all naturally available hard substrata bear mussel monocultures. In three in situ experiments we investigated the dominance of mussels and the influence of local consumers on establishment and dynamics of a benthic community: (a) the natural course of succession in the absence of benthic consumers was followed on vertically suspended settlement substrata, (b) settling plates were exposed to natural recruitment being either accessible or inaccessible to all benthic consumers, and (c) the three major local consumer species, viz. the shore crab Carcinus maenas, the starfish Asterias rubens and the periwinkle Littorina littorea, were enclosed separately in cages containing a settling panel to assess species-specific consumer effects on recruitment. The results illustrate that in this region of the Baltic Sea mussels do have the potential to dominate ungrazed substrata within a few weeks and that top-down effects (predation and grazing) may control community structure. While some species - mussels in particular - were suppressed by consumption, others seemed to benefit from the presence of consumers. Thus, barnacles and algae thrived when consumers were present. Blue mussels being the locally dominant competitor, the beneficial effects of consumers on barnacles and algae were presumably indirect ones through consumer-caused release from asymmetrical competition. The isolated effects of C. maenas, A. rubens and L. littorea, on recruitment differed in quality (positive vs. negative), quantity (strength of effect) and specificity. Barnacle recruitment was significantly reduced in the presence of both starfish and shore crabs. Diatom recruitment was significantly reduced by snails

  10. Pharmacological induction of larval settlement and metamorphosis in the blue mussel Mytilus edulis L.

    PubMed

    Dobretsov, Sergey V; Qian, Pei-Yuan

    2003-02-01

    The blue mussel Mytilus edulis L. is an important aquaculture and fouling species in northern seas. Although the general role of chemical cues for settlement of larvae of the blue mussel has been proposed, few studies have focused on induction of settlement and metamorphosis by pharmacological agents. In this study, the induction of larval settlement of the blue mussel by pharmacological compounds was investigated through a series of laboratory experiments with an aim of identifying artificial cues for laboratory bioassay systems in fouling and antifouling research. Gamma-aminobutiric acid (GABA), dihydroxyphenyl L-alanine (DOPA), isobutyl methylxanthine (IBMX) and acetylcholine chloride (ACH) at 10(-7)-10(-2) M as well as KCl at 10-40 mM K+ in excess of the level in normal seawater were tested for their inductive effect on larval settlement. In filtered seawater (FSW) < 9% of the larvae settled after 48 h. Elevated K+ and GABA levels had no effect on larval settlement and metamorphosis. DOPA at 10(-5) M and IBMX at 10(-6)-10(-4) M induced 41-83% larval settlement and ACH at 10(-7)-10(-5) M induced < 40% larval settlement. While the highest settlement rates were observed after 48 h exposure to the chemical, most of the larvae settled within 24 h. Compounds at concentrations of 10(-3)-10(-2) M were either toxic to larvae or retarded the growth of the post-larvae shell. Juveniles resulting from induction by lower concentrations of chemicals had a very high survival rate, completed metamorphosis and grew as well as the juveniles that metamorphosed spontaneously. IBMX at 10(-6)-10(-4) M and L-DOPA at 10(-5) M are effective agents for induction of settlement and metamorphosis for future studies using juvenile M. edulis. PMID:14618689

  11. Experimental Transmission of Infectious Pancreatic Necrosis Virus from the Blue Mussel, Mytilus edulis, to Cohabitating Atlantic Salmon (Salmo salar) Smolts

    PubMed Central

    Pietrak, Michael R.; Bricknell, Ian

    2013-01-01

    Integrated multitrophic aquaculture (IMTA) reduces the environmental impacts of commercial aquaculture systems by combining the cultivation of fed species with extractive species. Shellfish play a critical role in IMTA systems by filter-feeding particulate-bound organic nutrients. As bioaccumulating organisms, shellfish may also increase disease risk on farms by serving as reservoirs for important finfish pathogens such as infectious pancreatic necrosis virus (IPNV). The ability of the blue mussel (Mytilus edulis) to bioaccumulate and transmit IPNV to naive Atlantic salmon (Salmo salar) smolts was investigated. To determine the ability of mussels to filter and accumulate viable IPNV, mussels were held in water containing log 4.6 50% tissue culture infective dose(s) (TCID50) of the West Buxton strain of IPNV ml−1. Viable IPNV was detected in the digestive glands (DGs) of IPNV-exposed mussels as early as 2 h postexposure. The viral load in mussel DG tissue significantly increased with time and reached log 5.35 ± 0.25 TCID50 g of DG tissue−1 after 120 h of exposure. IPNV titers never reached levels that were significantly greater than that in the water. Viable IPNV was detected in mussel feces out to 7 days postdepuration, and the virus persisted in DG tissues for at least 18 days of depuration. To determine whether IPNV can be transmitted from mussels to Atlantic salmon, IPNV-exposed mussels were cohabitated with naive Atlantic salmon smolts. Transmission of IPNV did occur from mussels to smolts at a low frequency. The results demonstrate that a nonenveloped virus, such as IPNV, can accumulate in mussels and be transferred to naive fish. PMID:23872575

  12. Determination of thermal inactivation kinetics of hepatitis A virus in blue mussel (Mytilus edulis) homogenate.

    PubMed

    Bozkurt, Hayriye; D'Souza, Doris H; Davidson, P Michael

    2014-05-01

    Hepatitis A virus (HAV) is a food-borne enteric virus responsible for outbreaks of hepatitis associated with shellfish consumption. The objectives of this study were to determine the thermal inactivation behavior of HAV in blue mussels, to compare the first-order and Weibull models to describe the data, to calculate Arrhenius activation energy for each model, and to evaluate model efficiency by using selected statistical criteria. The times required to reduce the population by 1 log cycle (D-values) calculated from the first-order model (50 to 72°C) ranged from 1.07 to 54.17 min for HAV. Using the Weibull model, the times required to destroy 1 log unit (tD = 1) of HAV at the same temperatures were 1.57 to 37.91 min. At 72°C, the treatment times required to achieve a 6-log reduction were 7.49 min for the first-order model and 8.47 min for the Weibull model. The z-values (changes in temperature required for a 90% change in the log D-values) calculated for HAV were 15.88 ± 3.97°C (R(2), 0.94) with the Weibull model and 12.97 ± 0.59°C (R(2), 0.93) with the first-order model. The calculated activation energies for the first-order model and the Weibull model were 165 and 153 kJ/mol, respectively. The results revealed that the Weibull model was more appropriate for representing the thermal inactivation behavior of HAV in blue mussels. Correct understanding of the thermal inactivation behavior of HAV could allow precise determination of the thermal process conditions to prevent food-borne viral outbreaks associated with the consumption of contaminated mussels. PMID:24632250

  13. BMAA detected as neither free nor protein bound amino acid in blue mussels.

    PubMed

    Rosén, Johan; Westerberg, Erik; Schmiedt, Sebastian; Hellenäs, Karl-Erik

    2016-01-01

    The results of this study imply that β-methylamino-alanine (BMAA) obtained from extracts of blue mussels from the Swedish west coast is neither free nor protein bound. The results were obtained by separation (precipitation and ultrafiltration) of low and high molecular weight compounds from neutral extracts of blue mussels, and treatment of these extracts with low and high concentrations of acids, varying time and temperature. The main portion of BMAA was obtained from the low molecular weight fraction, released or formed at 95 °C in dilute acids. The measured amount of BMAA did not increase by strong acid treatment. Lysine was used as reference and was only released at significant amounts when treating the high molecular weight fraction with concentrated acid. The results also indicated that breakage of peptide bonds was not involved in the formation/release of BMAA in these extracts unless any BMAA peptide bond would be significantly more susceptible to dilute acid than e.g. the monitored lysine peptide bond. BMAA was measured using isotope dilution and detection of the underivatized compound by HILIC-UHPLC-MS/MS (Hydrophilic Interaction Liquid Chromatography, Ultra-High Performance Liquid Chromatography, tandem Mass Spectrometry). The findings might add to the understanding of conflicting data in the literature regarding the occurrence of BMAA, and have implications for studies on possible biomagnification of BMAA in the food chain and bioavailability from food. PMID:26577502

  14. Novel octabrominated phenolic diphenyl ether identified in blue mussels from the Swedish West Coast.

    PubMed

    Winnberg, Ulrika; Rydén, Andreas; Löfstrand, Karin; Asplund, Lillemor; Bignert, Anders; Marsh, Göran

    2014-03-18

    Hydroxylated (OH-) and methoxylated (MeO-) polybrominated diphenyl ethers (PBDEs) are compounds present in the marine environment and OH-PBDEs are of toxicological concern and are therefore of interest to monitor in the environment. A phenolic octaBDE was tentatively identified in the phenolic fraction of previously analyzed mussel samples after methylation of the halogenated phenolic compounds (HPCs). The aim of the present study was to confirm the identity of this compound in blue mussels and investigate whether the analyte is diOH- and/or OH-MeO-octaBDE. Two reference standards, 6,6'-dimethoxy-2,2',3,3',4,4',5,5'-octabromodiphenyl ether (6,6'-diMeO-BDE194) and 6-ethoxy-6'-methoxy-2,2',3,3',4,4',5,5'-octabromodiphenyl ether (6-EtO-6'-MeO-BDE194) were prepared via O-arylation of 2,3,4,5-tetrabromo-6-methoxyphenol and 2,3,4,5-tetrabromo-6-ethoxyphenol, respectively, with a novel unsymmetrical diaryliodonium salt, 2,3,4,5-tetrabromo-6-methoxydiphenyliodonium triflate. The GC retention time and GC/MS spectrum of the synthesized 6,6'-diMeO-BDE194 correspond well with the analyte in the methylated phenolic fraction of a mussel extract from a previous study. Structural analysis performed in this study indicate that the synthesized 6,6'-diMeO-BDE194 and 6-EtO-6'-MeO-BDE194 correspond well with 6-hydroxy-6'-methoxy-2,2',3,3',4,4',5,5'-octabromodiphenyl ether (6-OH-6'-MeO-BDE194) after methylation and ethylation, respectively, of the HPCs in the mussel extracts. The compound 6-OH-6'-MeO-BDE194 was identified and quantified in new mussels, sampled in 2012 from two locations on the Swedish west coast, with geometric mean concentrations of 3700 and 410 ng/g fat, respectively. PMID:24559155

  15. RESPONSES OF AN ESTUARINE POPULATION OF THE BLUE MUSSEL 'MYTILUS EDULIS' TO HEATED WATER FROM A STEAM GENERATING PLANT

    EPA Science Inventory

    An entire bed of the blue mussel Mytilus edulis, consisting of 5,000 individuals/cu.m., died during June, 1971 in the effluent canal of a steam generating plant when the temperature increased above 27C. Similarly, the population in the intake canal disappeared when temperatures r...

  16. Arsenic Speciation in Blue Mussels (Mytilus edulis) Along a Highly Contaminated Arsenic Gradient

    SciTech Connect

    Whaley-Martin, K.J.; Koch, I.; Moriarty, M.; Reimer, K.J.

    2012-11-01

    Arsenic is naturally present in marine ecosystems, and these can become contaminated from mining activities, which may be of toxicological concern to organisms that bioaccumulate the metalloid into their tissues. The toxic properties of arsenic are dependent on the chemical form in which it is found (e.g., toxic inorganic arsenicals vs nontoxic arsenobetaine), and two analytical techniques, high performance liquid chromatography coupled with inductively coupled plasma mass spectrometry (HPLC-ICP-MS) and X-ray absorption spectroscopy (XAS), were used in the present study to examine the arsenic species distribution in blue mussels (Mytilus edulis) obtained from an area where there is a strong arsenic concentration gradient as a consequence of mining impacted sediments. A strong positive correlation was observed between the concentration of inorganic arsenic species (arsenic compounds with no As-C bonds) and total arsenic concentrations present in M. edulis tissues (R{sup 2} = 0.983), which could result in significant toxicological consequences to the mussels and higher trophic consumers. However, concentrations of organoarsenicals, dominated by arsenobetaine, remained relatively constant regardless of the increasing As concentration in M. edulis tissue (R{sup 2} = 0.307). XANES bulk analysis and XAS two-dimensional mapping of wet M. edulis tissue revealed the presence of predominantly arsenic-sulfur compounds. The XAS mapping revealed that the As(III)-S and/or As(III) compounds were concentrated in the digestive gland. However, arsenobetaine was found in small and similar concentrations in the digestive gland as well as the surrounding tissue suggesting arsenobetaine may being used in all of the mussel's cells in a physiological function such as an intracellular osmolyte.

  17. The relevance of age to selected heavy metals within soft tissues of the blue mussel (Mytilus edulis)

    SciTech Connect

    Zimmer, R.D.

    1989-01-01

    The principal objective of this research effort was to address the relationship between age and concentrations of selected toxic trace metals within soft tissues of the blue mussel (Mytilus edulis). Blue mussels are commonly employed as sentinels of national and international biomonitoring programs because of their more or less ubiquitous distribution and ability to bioaccumulate pollutants of concern. For this study, mussels ranging in size from 50-80 millimeters (mm) were collected from two sites near Portland, Maine. Whole soft tissues from mussels ranging in age from 2-10 years were analyzed to determine concentrations of total zinc, cadmium, iron, lead, manganese, copper, and chromium. Results indicated a relatively high metal Coefficient of Variation (C.V.) between individuals from both sampling sites. In addition, copper, lead, cadmium, manganese and iron concentrations were found to be statistically related to tissue dry weight. Only two of the seven metals (cadmium and chromium) exhibited a correlation with mussel age. Data generated in this study reflect a need for investigators to exercise caution in comparing the quality of different coastal regions based on tissue burdens alone.

  18. Phylogenetic and morphological characterisation of the green algae infesting blue mussel Mytilus edulis in the North and South Atlantic oceans.

    PubMed

    Rodríguez, Francisco; Feist, Stephen W; Guillou, Laure; Harkestad, Lisbeth S; Bateman, Kelly; Renault, Tristan; Mortensen, Stein

    2008-09-24

    Blue mussels Mytilus edulis with shell deformations and green pustules containing parasitic algae were collected at 3 coastal sites (Burøy, Norway; Bockholm, Denmark; Goose Green, Falkland Islands). A comparative study, including mussel histopathology, algal morphology, ultrastructure and phylogenetic position was performed. Green pustules were mainly located in the posterior portion of the mantle and gonad tissues and the posterior adductor muscle. Electron microscopy confirmed the presence of algal cells with similar morphology to Coccomyxa parasitica. Algae were oval shaped with a single nucleus and chloroplast, 1 or 2 mitochondria and a dense granular cytoplasm with a lipid inclusion body, Golgi apparatus and small vesicles. Partial small subunit (SSU) rRNA phylogeny confirmed the inclusion of parasitic algae into the Coccomyxa clade. However, the sequence identity between almost full SSU rRNA sequences of parasitic algae and others in this clade yielded an unexpected result. Green algae from mussels were distant from C. parasitica Culture Collection of Algae and Protozoa (CCAP) strain 216/18 (94% identity), but very similar (99% identity) to C. glaronensis (a lichen endosymbiont) and green endophytes from the tree Ginkgo biloba. The CCAP strain 216/18 was a sister sequence to Nannochloris algae, far from the Coccomyxa clade. These results suggest a misidentification or outgrowth of the original CCAP strain 216/18 by a different 'Nannochloris-like' trebouxiophycean organism. In contrast, our sequences directly obtained from infested mussels could represent the true C. parasitica responsible for the green pustules in blue mussels. PMID:18998587

  19. Resource subsidies from multi-trophic aquaculture affect isotopic niche width in wild blue mussels (Mytilus edulis)

    NASA Astrophysics Data System (ADS)

    Weldrick, C. K.; Jelinski, D. E.

    2016-05-01

    Blue mussels (Mytilus edulis) are boreo-temperate, filter-feeding bivalves common to intertidal areas. As filter-feeders they have been employed in open-water, multi-tropic aquaculture systems to reduce organic benthic loading though the exploitation of suspended particulate organic materials. We compared δ13C and δ15N signatures and the isotopic niches of mussels growing in, and adjacent to, an integrated multi-trophic aquaculture (IMTA) farm in British Columbia, Canada, and using this information evaluated the contribution of aquaculture-derived effluent to their diet. Farm-sampled mussels had the least intraspecific isotopic variation compared to mussels sampled at the reference site. The interaction between time (i.e. sampling dates) and site did not significantly affect the isotopic composition of mussels; however significant variation was detected in δ15N values as a function of sampling date and particulate organic matter. A two-source isotopic mixing model indicated that marine particulate organic matter and IMTA farm effluent were approximately equal in importance (~ 46 % and ~ 54 %, respectively) to the diet of IMTA-retrieved mussels. Uptake of IMTA farm waste by M. edulis supports their use as economic extractives while also mitigating farmed sablefish (Anoplopoma fimbria) nutrient loading to the aquatic environment.

  20. Integrated biomarker assessment of the effects of tailing discharges from an iron ore mine using blue mussels (Mytilus spp.).

    PubMed

    Brooks, Steven J; Harman, Christopher; Hultman, Maria T; Berge, John Arthur

    2015-08-15

    The blue mussel (Mytilus spp.) has been used to assess the potential biological effects of the discharge effluent from the Sydvaranger mine, which releases its tailings into Bøk fjord at Kirkenes in the north of Norway. Metal bioaccumulation and a suite of biomarkers were measured in mussels positioned for 6 weeks at varying distances from the discharge outlet. The biomarkers used included: stress on stress (SS); condition index (CI); cellular energy allocation (CEA); micronuclei formation (MN); lysosomal membrane stability (LMS), basophilic cell volume (VvBAS); and neutral lipid (NL) accumulation. The individual biomarkers were integrated using the integrated biological response (IBR/n) index. The accumulation of Fe was significantly higher in mussels located closer to the discharge outlet, indicating that these mussels had been exposed to the suspended mine effluent. The IBR/n results were in good agreement with the location of the mussels in relation to the distance from the discharge outlet and expected exposure to the mine effluent. Several biomarkers showed responses resulting in higher IBR/n values of analysed mussels within a 3 km distance from the tailing discharge. PMID:25889549

  1. Allometric equations for maximum filtration rate in blue mussels Mytilus edulis and importance of condition index

    NASA Astrophysics Data System (ADS)

    Riisgård, Hans Ulrik; Larsen, Poul S.; Pleissner, Daniel

    2014-03-01

    The relationship between body dry weight ( W) and shell length ( L) of blue mussels, Mytilus edulis, can be expressed by the condition index (CI = W/ L 3) which varies from population to population and during the year. Here, we examine the influence of CI on the relationships between maximum filtration rate ( F, l h-1), W (g), and L (mm) as described by the equations: F W = aW b and F L = cL d , respectively. This is done by using available and new experimental laboratory data on M. edulis obtained by members of the same research team using different methods and controlled diets of cultivated algal cells. For all data, it was found that F W = 6.773 W 0.678 and F L = 0.00135 L 2.088 which are very similar to equations for mussels with `medium condition' (CI = 4-6 mg cm-3): F W = 6.567 W 0.681 and F L = 0.00150 L 2.051, with b- and d-values within a few percent of the theoretically expected of 2/3 and 2, respectively. Further, based on the present data, we propose a correction factor expressed by the empirical relation F W / F L = 0.3562CI2/3 which implies that F W tends to underestimate the actual filtration rate ( F L ) when CI < 4.70 and to overestimate the filtration rate when CI > 4.70.

  2. A Marteilia-like parasite in blue mussels Mytilus edulis in China.

    PubMed

    Wang, Zhongwei; Lu, Xin; Liang, Yubo; Zheng, Zheng

    2012-09-01

    Species of the genus Marteilia (Phylum Paramyxea) are protozoan parasites of marine mollusks. Marteilia spp. have been detected in mollusks from different parts of the world, but the presence of these parasites in China has not been previously reported. Therefore, a survey was conducted to look for the presence of Marteilia spp. in blue mussels Mytilus edulis and Asian green mussels Perna viridis collected along China's coasts. Histological and PCR analyses revealed that 5 of 180 M. edulis (prevalence = 2.8%) were positive for infection with a Marteilia-like organism, whereas the parasite was not detected in any of the 80 P. viridis individuals tested. Total genomic DNA was extracted from the infected tissue sections for PCR amplification. The PCR amplification with Marteilia primers SS1 and SAS1 yielded the expected 641-bp product. Sequencing results showed that the 18S ribosomal RNA gene fragment from the protozoans found in M. edulis from China was 88% similar to that of Marteilia refringens, a species that was reported from M. edulis and European flat oysters Ostrea edulis collected in France. This is the first report of a Marteilia-like organism infecting M. edulis in China. PMID:22897134

  3. Enhanced accumulation of PCB congeners by Baltic Sea blue mussels, Mytilus edulis, with increased algae enrichment

    SciTech Connect

    Gilek, M.; Bjoerk, M.; Broman, D.; Kautsky, N.; Naef, C.

    1996-09-01

    The objective of this study was to examine if natural variations in the quantity of phytoplankton-derived particulate and dissolved organic carbon influences the accumulation of polychlorinated biphenyls (PCBs) in the tissues of Baltic Sea blue mussels (Mytilus edulis L.). In a laboratory flow-through experiment the authors exposed M. edulis to the technical PCB mixture Aroclor{reg_sign} 1248 for 21 d at three different enrichments of the unicellular green algae Chlamydomonas sp., 0.10, 0.16, and 0.32 mg particulate organic carbon (POC)/L. Tissue and water concentrations were determined for seven PCB congeners and 21-d bioaccumulation factors were calculated against total water concentrations. Contrary to what would be expected, an increase in algae enrichment from 0.10 to 0.32 mg POC/L resulted in an enhanced PCB accumulation by a factor of approx. 2. This increase in PCB accumulation was more pronounced for PCB congeners with lower hydrophobicity. These observations have implications for the design of laboratory accumulation studies and potentially for PCB accumulation and cycling in field populations of suspension-feeding mussels in response to changes in eutrophication status.

  4. Effects of nanopolystyrene on the feeding behavior of the blue mussel (Mytilus edulis L.).

    PubMed

    Wegner, A; Besseling, E; Foekema, E M; Kamermans, P; Koelmans, A A

    2012-11-01

    As the industrial production of nanoplastic and the degradation of microplastic into smaller particles at sea increase, the potential amount of nanoplastics in the marine environment rises. It has been reported that mussels uptake 100-nm polystyrene (PS) beads; to date, however, the effects of this uptake on the organism are unknown. In the present study, the authors investigated the effects of 30-nm PS on the feeding behavior of the blue mussel (Mytilus edulis) by exposing the organism to different nano PS and different algae (Pavlova lutheri) concentrations. The state of nano PS aggregation in the exposure medium was assessed using dynamic light scattering. In all treatments that contained nano PS, M. edulis produced pseudofeces. The total weight of the feces and pseudofeces increased with increasing nano PS and increasing algae concentration. Furthermore, M. edulis reduced its filtering activity when nano PS was present but still caused a decrease in the apparent nano PS concentration in the water. The presence of nano PS around the foot of M. edulis after the bioassay confirmed that the organism removed nano PS from the water. Chronic effect studies are therefore needed to investigate the effects of nanoplastics in M. edulis and possible consequences for its predators, including humans. PMID:22893562

  5. Species profiles: Life histories and environmental requirements of coastal fishes and invertebrates (North and Mid-Atlantic): Blue mussel

    SciTech Connect

    Newell, R.I.E.

    1989-06-01

    The blue mussel, Mytilus edulis L. is a widely distributed and locally abundant bivalve mollusc in the North and Mid-Atlantic Regions. It is a valuable commercial species; regional landings in 1986 were worth nearly $4 million. It is a semi-sessile species, anchored by byssus threads to firm surfaces in littoral and sub-littoral environments at salinities ranging from 5 to 35 ppt. It is a suspension feeder, ingesting phytoplankton and detrital particles in the size range of 3--30 /mu/m. The geographical range of the species is limited by lethal water temperatures above 27/degree/C in the south and by temperatures too low for growth and reproduction in the north. Animals from the northern end of the range are stressed by temperatures above 20/degree/C, whereas those near the southern distributional limit are not severely stressed by temperatures as high as 25/degree/C. The blue mussel is diecious and oviparous. The planktotrophic larvae take about 3 weeks to develop and metamorphose. The environmental tolerances of larvae are more restricted than those of adults. The juveniles grow to approximately 1.5 mm while attached to filamentous algae before being carried by water currents to reattach to a firm substrate, often close to adult mussels. Larval and adult blue mussels are important prey items for many animals, including crabs, fishes, and birds. 95 refs., 5 figs., 2 tabs.

  6. An assessment of persistent organic pollutants (POPs) in wild and rope grown blue mussels (Mytilius edulis) from Scottish coastal waters.

    PubMed

    Webster, L; Russell, M; Walsham, P; Phillips, L A; Packer, G; Hussy, I; Scurfield, J A; Dalgarno, E J; Moffat, C F

    2009-06-01

    Farmed, rope grown mussels (Loch Etive and Loch Ewe, both on the west coast of Scotland) and wild mussels (Straad on the west coast and Shell Bay and Aberdeen Breakwater, both on the east coast of Scotland) were collected on a monthly basis and analysed for persistent organic pollutants (POPs) with the aim of assessing the status of Scottish mussels, with respect to concentrations of POPs, and investigating site-specific and seasonal differences. Samples were analysed for polycyclic aromatic hydrocarbons (PAHs), polybrominated diphenyl ethers (PBDEs) and chlorobiphenyls (CBs). Total PAH (2- to 6-ring parent and alkylated) concentrations in mussels from three pristine sites (ref. 1: ICES Marine Chemistry Working Group Report 2008, http://www.ices.dk/reports/MHC/2007/MCWG07.pdf) (Loch Etive, Loch Ewe and Straad) were significantly lower than in mussels from sites with greater coastal influences (Aberdeen Breakwater and Shell Bay). Seasonal trends in the PAH concentrations were evident at the pristine sites, with concentrations being significantly higher for samples collected between November and March compared to those collected between April and October. The PAH data was assessed using a recently proposed traffic light system, based on the assessment criteria adopted by OSPAR for use in the 2008 Coordinated Environmental Monitoring Programme (CEMP) assessment. Concentrations were compared to Background Assessment Concentrations (BAC; blue/green transition) and Environmental Assessment Concentrations (EACs; green/red transition). All sites were classed as 'green' for the PAHs analysed, being below EACs, where available. The pristine sites were also below BACs for some PAHs and therefore would be classed as 'blue' for these PAHs. CBs and PBDEs were measured in mussels collected between 2006 and 2008 inclusive. Concentrations for CB and PBDEs were significantly higher in the Aberdeen Breakwater mussels than for all other sites. Concentrations at all sites were low with

  7. Applying Dynamic Energy Budget (DEB) theory to simulate growth and bio-energetics of blue mussels under low seston conditions

    NASA Astrophysics Data System (ADS)

    Rosland, R.; Strand, Ø.; Alunno-Bruscia, M.; Bacher, C.; Strohmeier, T.

    2009-08-01

    A Dynamic Energy Budget (DEB) model for simulation of growth and bioenergetics of blue mussels ( Mytilus edulis) has been tested in three low seston sites in southern Norway. The observations comprise four datasets from laboratory experiments (physiological and biometrical mussel data) and three datasets from in situ growth experiments (biometrical mussel data). Additional in situ data from commercial farms in southern Norway were used for estimation of biometrical relationships in the mussels. Three DEB parameters (shape coefficient, half saturation coefficient, and somatic maintenance rate coefficient) were estimated from experimental data, and the estimated parameters were complemented with parameter values from literature to establish a basic parameter set. Model simulations based on the basic parameter set and site specific environmental forcing matched fairly well with observations, but the model was not successful in simulating growth at the extreme low seston regimes in the laboratory experiments in which the long period of negative growth caused negative reproductive mass. Sensitivity analysis indicated that the model was moderately sensitive to changes in the parameter and initial conditions. The results show the robust properties of the DEB model as it manages to simulate mussel growth in several independent datasets from a common basic parameter set. However, the results also demonstrate limitations of Chl a as a food proxy for blue mussels and limitations of the DEB model to simulate long term starvation. Future work should aim at establishing better food proxies and improving the model formulations of the processes involved in food ingestion and assimilation. The current DEB model should also be elaborated to allow shrinking in the structural tissue in order to produce more realistic growth simulations during long periods of starvation.

  8. Monitoring water quality in Sydney Harbour using blue mussels during remediation of the Sydney Tar Ponds, Nova Scotia, Canada.

    PubMed

    Walker, Tony R; MacAskill, Devin

    2014-03-01

    Using mussels as monitoring tools we measured water quality in Sydney Harbour during a large scale, multi-year remediation project of the Sydney Tar Ponds (STPs); one of Canada's most contaminated sites. Chemical contaminants were measured in blue mussels (Mytilus edulis) in Sydney Harbour, which were used as monitoring tools to assess the spatio-temporal distribution of polycyclic aromatic hydrocarbons (PAHs); polychlorinated biphenyls (PCBs); metals (As, Cd, Cu, Hg, Pb, Zn) and lipid content during baseline and 3 years of remediation. The overall spatio-temporal distribution of chemicals in mussels was also compared to contaminants in other marine indicators (e.g., sediment, water and crab tissue). Measured metal concentrations in mussels showed some minor temporal variability (4 years), but these did not appear to be directly related to remediation activities, with the highest concentrations of As, Hg and Zn measured at reference stations. Most measured contaminants showed stable or potentially decreasing concentrations during the study, except Pb and Zn. Individual PAH compounds were mostly undetected during baseline and remediation, except for fluoranthene and pyrene. Concentrations of fluoranthene in mussels and deep water samples were moderately related. Generally, PCBs were undetected (<0.05 μg g(-1)), except during year 2 remediation at some near-field stations. Contaminants measured during this study were at much lower concentrations than previously reported in other studies of mussels in Sydney Harbour and eastern Canada. This is likely due to the ongoing natural recovery of Sydney Harbour and to a lesser extent because of the environmental mitigation protection measures implemented during remediation activities at the STPs. The lack of detection of most individual PAHs and PCBs, plus relatively low bio-accumulation of metals observed during baseline and remediation attest to the effectiveness of using mussels as monitoring tools for environmental

  9. Endocrine disruptors in blue mussels and sediments from the Gulf of Gdańsk (Southern Baltic).

    PubMed

    Filipkowska, Anna; Lubecki, Ludwik

    2016-07-01

    Samples of blue mussel (Mytilus trossulus) and sediment were collected in the Gulf of Gdańsk (Southern Baltic Sea) to assess the extent of their contamination with two groups of endocrine disruptors: 4-nonylphenols and organotins (butyl- and phenyltins). Five sampling stations were chosen along the coastline of the Tricity Agglomeration (Gdańsk, Sopot, Gdynia) in 2008, 2012, and 2013. No evident differences between the three campaigns were found in either the mussel or the sediment samples. The mussels were moderately contaminated with 4-nonylphenols (30-111 ng g(-1) d.w.), whereas the levels of these compounds in the sediment samples were very low (0.8-2.7 ng g(-1) d.w.). Total concentrations of butyltin compounds in the mussels and sediments ranged between 41 and 164 ng Sn g(-1) d.w., and from below the limit of detection to 22 ng Sn g(-1) d.w., respectively, whereas phenyltins were not detected in any of the samples. Butyltin degradation indices indicate an old tributyltin input into the coastal environment, which is characterized by intense maritime activity. The results obtained from this work demonstrate that 5 years after the total ban on using organotin-based antifouling paints was imposed, butyltins are still present in mussels and sediments of the Gulf of Gdańsk. PMID:27032637

  10. Natural products for mitigation of fouling by the blue mussel, Mytilus edulis, in marine water intake systems

    SciTech Connect

    Taylor, G.T.; Zheng, D.

    1995-06-01

    In search of natural antifouling products, sedentary organisms - free of epibiotic communities - were collected from the inter- and subtidal zones of Long Island Sound. Crude solvent extracts from these specimens were subjected to 2 - 4 bioassays to screen for: (1) microbila sensitivity, (2) response of mussel byssal thread secretion using Mytilus edulis, (3) mussel larval settlement response, and (4) bacterial attachment response. Of the 86 extracts derived from 24 organisms, six very promising extracts have been isolated from local algae and invertebrates that exhibit strong antifouling activity against the blue mussel, the major biofouler in northeastern American coastal utilities. The most promising extracts exhibiting strong inhibition of microbial growth and settlement. The process of identification of the active agent through further purification and subsequent bioassays is ongoing. A model hybrid coating, incorporating an extract from Fucuc filiformis into a silicon polymer-based matrix (EXTRUDE{sup {trademark}}), effectively prevented byssal thread attachment by juvenile blue mussels and killed specimens close to treated areas within 10 days.

  11. The mass mortality of blue mussels (Mytilus spp.) from the Atlantic coast of France is associated with heavy genomic abnormalities as evidenced by flow cytometry.

    PubMed

    Benabdelmouna, Abdellah; Ledu, Christophe

    2016-07-01

    Since 2014, France's blue mussel industry has been facing heavy mortality outbreaks (90-100%) affecting both juveniles and adults. This report presents evidence of heavy genomic abnormalities associated with mortality outbreaks in blue mussels, Mytilus edulis-galloprovincialis, from the Atlantic coast of France. In this study, ploidy characteristics of hemic cells were investigated using Flow CytoMetry (FCM), revealing an unusual, broad continuum of ploidy distribution from hypodiploidy to tetraploidy. FCM was additionally used to evaluate, at individual and populations levels, different thresholds of genomic abnormality (GA%) using the percentage of non-diploid nuclei. Individual mussels were considered to be abnormal when more than 10% of hemocytes in S-G2/M phase were present. At the population level, a threshold of 6% for the mean intensity of the abnormality is proposed, which means in the population, more than 6% of individual mussels have to present with more than 10% of their hemocytes in S-G2/M phase. GA% was found to be significantly predictive of the final mortality. Based on the established thresholds, only two mussel stocks analyzed in this study were considered to have good cytogenetic quality, while all other stocks appeared to be affected. FCM offers a very powerful tool to help manage current blue mussel mortality in France. We also believe that annual and extensive determination of cytogenetic quality of wild and cultivated mussel beds along with exclusive use of FCM-qualified mussel seeds should be a priority. PMID:27264803

  12. Spatial distribution and accumulation of brominated flame retardants, polychlorinated biphenyls and organochlorine pesticides in blue mussels (Mytilus edulis) from coastal waters of Korea.

    PubMed

    Ramu, Karri; Kajiwara, Natsuko; Isobe, Tomohiko; Takahashi, Shin; Kim, Eun-Young; Min, Byung-Yoon; We, Sung-Ug; Tanabe, Shinsuke

    2007-07-01

    Blue mussels (Mytilus edulis) from 20 locations along the coastal waters of Korea were analyzed to elucidate the characteristic distribution and contamination status of polybrominated diphenyl ethers (PBDEs), hexabromocyclododecanes (HBCDs), polychlorinated biphenyls (PCBs) and organochlorine pesticides. To our knowledge, this is the first study to report on the contamination status of HBCDs from Korea. PBDEs and HBCDs were found in mussels at levels ranging from 6.6 to 440 and from 6.0 to 500 ng/g lipid wt., respectively. Concentrations of PBDEs in mussels from Korea were higher or comparable to available data in mussels from other countries. Among the organochlorine compounds (OCs) analyzed, levels of PCBs and DDTs were the highest followed by CHLs, HCHs and hexachlorobenzene. For all the compounds, higher concentrations were found in mussels from southeastern coast of Korea. The present study shows the importance of mussels as bioindicators for monitoring contaminants in coastal waters. PMID:17240498

  13. Effect of ocean acidification on the early life stages of the blue mussel (Mytilus edulis)

    NASA Astrophysics Data System (ADS)

    Gazeau, F.; Gattuso, J.-P.; Dawber, C.; Pronker, A. E.; Peene, F.; Peene, J.; Heip, C. H. R.; Middelburg, J. J.

    2010-04-01

    Several experiments have shown a decrease of growth and calcification of organisms at decreased pH levels but relatively few studies have focused on early life stages which are believed to be more sensitive to environmental disturbances such as hypercapnia. Here, we present experimental data demonstrating that the growth of planktonic mussel (Mytilus edulis) larvae is significantly affected by a decrease of pH to a level expected for the end of the century. Even though there was no significant effect of a 0.25-0.34 pH unit decrease on hatching and mortality rates during the first 2 days of development nor during the following 13-day period prior to settlement, final shells were, respectively, 4.5±1.3 and 6.0±2.3% smaller at pHNBS~7.8 than at a control pHNBS of ~8.1. Moreover, a decrease of 12.0±5.4% of shell thickness was observed. More severe impacts were found with a decrease of ~0.5 pHNBS unit during the first 2 days of development which could be attributed to a decrease of calcification due toslight undersaturation of seawater with respect to aragonite. Indeed, important effects on both hatching and D-veliger shell growth were found. Hatching rates were 24±4% lower while D-veliger shells were 12.7±0.9% smaller at pHNBS~7.6 than at a control pHNBS of ~8.1. Although these results show that blue mussel larvae are still able to develop a shell in seawater undersaturated with respect to aragonite, decreases of hatching rates and shell growth suggest a negative impact of ocean acidification on the future survival of bivalve populations potentially leading to significant ecological and economical losses.

  14. Impact of ocean acidification on antimicrobial activity in gills of the blue mussel (Mytilus edulis).

    PubMed

    Hernroth, B; Baden, S; Tassidis, H; Hörnaeus, K; Guillemant, J; Bergström Lind, S; Bergquist, J

    2016-08-01

    Here, we aimed to investigate potential effects of ocean acidification on antimicrobial peptide (AMP) activity in the gills of Mytilus edulis, as gills are directly facing seawater and the changing pH (predicted to be reduced from ∼8.1 to ∼7.7 by 2100). The AMP activity of gill and haemocyte extracts was compared at pH 6.0, 7.7 and 8.1, with a radial diffusion assay against Escherichia coli. The activity of the gill extracts was not affected by pH, while it was significantly reduced with increasing pH in the haemocyte extracts. Gill extracts were also tested against different species of Vibrio (V. parahaemolyticus, V. tubiashii, V. splendidus, V. alginolyticus) at pH 7.7 and 8.1. The metabolic activity of the bacteria decreased by ∼65-90%, depending on species of bacteria, but was, as in the radial diffusion assay, not affected by pH. The results indicated that AMPs from gills are efficient in a broad pH-range. However, when mussels were pre-exposed for pH 7.7 for four month the gill extracts presented significantly lower inhibit of bacterial growth. A full in-depth proteome investigation of gill extracts, using LC-Orbitrap MS/MS technique, showed that among previously described AMPs from haemocytes of Mytilus, myticin A was found up-regulated in response to lipopolysaccharide, 3 h post injection. Sporadic occurrence of other immune related peptides/proteins also pointed to a rapid response (0.5-3 h p.i.). Altogether, our results indicate that the gills of blue mussels constitute an important first line defence adapted to act at the pH of seawater. The antimicrobial activity of the gills is however modulated when mussels are under the pressure of ocean acidification, which may give future advantages for invading pathogens. PMID:27288994

  15. Mass spectrometry data from a quantitative analysis of protein expression in gills of immuno-challenged blue mussels (Mytilus edulis).

    PubMed

    Hörnaeus, K; Guillemant, J; Mi, J; Hernroth, B; Bergquist, J; Lind, S Bergström

    2016-09-01

    Here, we provide the dataset associated with our research article on the potential effects of ocean acidification on antimicrobial peptide (AMP) activity in the gills of Mytilus edulis, "Impact of ocean acidification on antimicrobial activity in gills of the blue mussel (Mytilus edulis)" [1]. Blue mussels were stimulated with lipopolysaccharides and samples were collected at different time points post injection. Protein extracts were prepared from the gills, digested using trypsin and a full in-depth proteome investigation was performed using liquid chromatography coupled to tandem mass spectrometry (LC-MS/MS). Protein identification and quantification was performed using the MaxQuant 1.5.1.2 software, "MaxQuant enables high peptide identification rates, individualized p.p.b.-range mass accuracies and proteome-wide protein quantification" [2]. PMID:27358907

  16. Invasive blue mussels threaten regional scale genetic diversity in mainland and remote offshore locations: the need for baseline data and enhanced protection in the Southern Ocean.

    PubMed

    Gardner, Jonathan P A; Zbawicka, Małgorzata; Westfall, Kristen M; Wenne, Roman

    2016-09-01

    Human-mediated biological transfers of species have substantially modified many ecosystems with profound environmental and economic consequences. However, in many cases, invasion events are very hard to identify because of the absence of an appropriate baseline of information for receiving sites/regions. In this study, use of high-resolution genetic markers (single nucleotide polymorphisms - SNPs) highlights the threat of introduced Northern Hemisphere blue mussels (Mytilus galloprovincialis) at a regional scale to Southern Hemisphere lineages of blue mussels via hybridization and introgression. Analysis of a multispecies SNP dataset reveals hotspots of invasive Northern Hemisphere blue mussels in some mainland New Zealand locations, as well as the existence of unique native lineages of blue mussels on remote oceanic islands in the Southern Ocean that are now threatened by invasive mussels. Samples collected from an oil rig that has moved between South Africa, Australia, and New Zealand were identified as invasive Northern Hemisphere mussels, revealing the relative ease with which such non-native species may be moved from region to region. In combination, our results highlight the existence of unique lineages of mussels (and by extension, presumably of other taxa) on remote offshore islands in the Southern Ocean, the need for more baseline data to help identify bioinvasion events, the ongoing threat of hybridization and introgression posed by invasive species, and the need for greater protection of some of the world's last great remote areas. PMID:27124277

  17. Accumulation, transformation and breakdown of DSP toxins from the toxic dinoflagellate Dinophysis acuta in blue mussels, Mytilus edulis.

    PubMed

    Nielsen, Lasse Tor; Hansen, Per Juel; Krock, Bernd; Vismann, Bent

    2016-07-01

    Okadaic acid (OA), dinophysistoxins (DTX) and pectenotoxins (PTX) produced by the dinoflagellates Dinophysis spp. can accumulate in shellfish and cause diarrhetic shellfish poisoning upon human consumption. Shellfish toxicity is a result of algal abundance and toxicity as well as accumulation and depuration kinetics in mussels. We mass-cultured Dinophysis acuta containing OA, DTX-1b and PTX-2 and fed it to the blue mussel, Mytilus edulis under controlled laboratory conditions for a week to study toxin accumulation and transformation. Contents of OA and DTX-1b in mussels increased linearly with incubation time, and the net toxin accumulation was 66% and 71% for OA and DTX-1b, respectively. Large proportions (≈50%) of both these toxins were transformed to fatty acid esters. Most PTX-2 was transformed to PTX-2 seco-acid and net accumulation was initially high, but decreased progressively throughout the experiment, likely due to esterification and loss of detectability. We also quantified depuration during the subsequent four days and found half-life times of 5-6 days for OA and DTX-1b. Measurements of dissolved toxins revealed that depuration was achieved through excreting rather than metabolizing toxins. This is the first study to construct a full mass balance of DSP toxins during both accumulation and depuration, and we demonstrate rapid toxin accumulation in mussels at realistic in situ levels of Dinophysis. Applying the observed accumulation and depuration kinetics, we model mussel toxicity, and demonstrate that a concentration of only 75 Dinophysis cells l(-1) is enough to make 60 mm long mussels exceed the regulatory threshold for OA equivalents. PMID:27045361

  18. Perturbation induced changes in substrate use by the blue mussel, Mytilus edulis, in sedimentary systems

    NASA Astrophysics Data System (ADS)

    wa Kangeri, Arno K.; Jansen, Jeroen M.; Barkman, Barbara R.; Donker, Jasper J. A.; Joppe, Daniel J.; Dankers, Norbert M. J. A.

    2014-01-01

    For sessile benthic marine organisms adhesion to a stable substrate is important for survival. Sedimentary systems, however, generally lack stable surfaces. How sessile species like the mussel, Mytilus edulis, are able to achieve stability in unstable sediments is not fully understood. An intertidal mussel bed in the tidal flats in the Western portion of the Dutch Wadden Sea was selected to investigate adhesion behavior of M. edulis. Sampling was conducted along a hydrodynamic gradient along the Front-edge, Center and Back-edge of a mussel bed. Mussels along the bed edges were characterized by adhesion to fine shell debris and high numbers of byssus threads. Mussels in the center of the bed were characterized by adhesion to shells of living conspecifics and relatively low numbers of byssus threads. An experimental investigation to isolate the role of perturbation on adhesion strategies was carried out under laboratory conditions. Experimental results show that under perturbed conditions mussels developed increased numbers of byssus threads relative to mussels left unperturbed. Additionally, mussels subjected to perturbation preferentially adhered more frequently to fine shell debris while unperturbed mussels adhered more frequently to conspecifics. Results show that differentiation in adhesion strategy is driven by physical perturbation and mediated by bed density. The results also suggest that adhesion by mussels in a sedimentary environment is a selective process in which larger shell fragments and shells of conspecifics are the preferred substrate.

  19. SAR of Sponge-Inspired Hemibastadin Congeners Inhibiting Blue Mussel PhenolOxidase.

    PubMed

    Niemann, Hendrik; Hagenow, Jens; Chung, Mi-Young; Hellio, Claire; Weber, Horst; Proksch, Peter

    2015-05-01

    Hemibastadin derivatives, including the synthetically-derived 5,5'-dibromohemibastadin-1 (DBHB), are potent inhibitors of blue mussel phenoloxidase (PO), which is a key enzyme involved in the firm attachment of this invertebrate to substrates and, thus, a promising molecular target for anti-fouling research. For a systematic investigation of the enzyme inhibitory activity of hemibastadin derivatives, we have synthesized nine new congeners, which feature structural variations of the DBHB core structure. These structural modifications include, e.g., different halogen substituents present at the aromatic rings, different amine moieties linked to the (E)-2-(hydroxyimino)-3-(4-hydroxyphenyl)propionic acid, the presence of free vs. substituted aromatic hydroxyl groups and a free vs. methylated oxime group. All compounds were tested for their inhibitory activity towards the target enzyme in vitro, and IC50 values were calculated. Derivatives, which structurally closely resemble sponge-derived hemibastadins, revealed superior enzyme inhibitory properties vs. congeners featuring structural moieties that are absent in the respective natural products. This study suggests that natural selection has yielded structurally-optimized antifouling compounds. PMID:25988522

  20. SAR of Sponge-Inspired Hemibastadin Congeners Inhibiting Blue Mussel PhenolOxidase

    PubMed Central

    Niemann, Hendrik; Hagenow, Jens; Chung, Mi-Young; Hellio, Claire; Weber, Horst; Proksch, Peter

    2015-01-01

    Hemibastadin derivatives, including the synthetically-derived 5,5′-dibromohemibastadin-1 (DBHB), are potent inhibitors of blue mussel phenoloxidase (PO), which is a key enzyme involved in the firm attachment of this invertebrate to substrates and, thus, a promising molecular target for anti-fouling research. For a systematic investigation of the enzyme inhibitory activity of hemibastadin derivatives, we have synthesized nine new congeners, which feature structural variations of the DBHB core structure. These structural modifications include, e.g., different halogen substituents present at the aromatic rings, different amine moieties linked to the (E)-2-(hydroxyimino)-3-(4-hydroxyphenyl)propionic acid, the presence of free vs. substituted aromatic hydroxyl groups and a free vs. methylated oxime group. All compounds were tested for their inhibitory activity towards the target enzyme in vitro, and IC50 values were calculated. Derivatives, which structurally closely resemble sponge-derived hemibastadins, revealed superior enzyme inhibitory properties vs. congeners featuring structural moieties that are absent in the respective natural products. This study suggests that natural selection has yielded structurally-optimized antifouling compounds. PMID:25988522

  1. Negative effects of blue mussel ( Mytilus edulis) presence in eelgrass ( Zostera marina) beds in Flensborg fjord, Denmark

    NASA Astrophysics Data System (ADS)

    Vinther, Hanne Fogh; Laursen, Jens Sund; Holmer, Marianne

    2008-03-01

    The effect of blue mussel ( Mytilus edulis) presence in eelgrass ( Zostera marina) beds was studied from June 2004 to July 2005 in Flensborg fjord, Denmark. The field experiments were conducted at two stations, one with only Z. marina (Eelgrass station) present and one where M. edulis were present in the Z. marina beds (Mixed station). Zostera marina parameters were measured (growth of leaves, shoot density, leaf length, and nutrient content) in combination with epiphyte cover and sediment parameters (sulphate reduction rates, sediment nutrient fluxes, organic content, C, N and P content) to examine possible positive and negative effects of the mussels on eelgrass performance. The fluxes of ammonium from the sediments were stimulated at all sampling dates at the Mixed station, and possibly stimulated epiphyte growth at this station. Further 15N signals in epiphytes from the Mixed station suggested that excretion products from the mussels were important nitrogen sources at this station. Sulphate reduction rates were enhanced at the Mixed station and also sediment sulphide concentrations increased under mussel influence, which may have resulted in sulphide toxicity and decreased growth of Z. marina at this station. The study indicates that for Z. marina beds in Flensborg Fjord the effects of M. edulis in seagrass beds are primarily negative, and raises the question whether this leads to negative effects on the stability and expansion of Z. marina beds.

  2. Effect of ocean acidification on the early life stages of the blue mussel Mytilus edulis

    NASA Astrophysics Data System (ADS)

    Gazeau, F.; Gattuso, J.-P.; Dawber, C.; Pronker, A. E.; Peene, F.; Peene, J.; Heip, C. H. R.; Middelburg, J. J.

    2010-07-01

    Several experiments have shown a decrease of growth and calcification of organisms at decreased pH levels. There is a growing interest to focus on early life stages that are believed to be more sensitive to environmental disturbances such as hypercapnia. Here, we present experimental data, acquired in a commercial hatchery, demonstrating that the growth of planktonic mussel (Mytilus edulis) larvae is significantly affected by a decrease of pH to a level expected for the end of the century. Even though there was no significant effect of a 0.25-0.34 pH unit decrease on hatching and mortality rates during the first 2 days of development nor during the following 13-day period prior to settlement, final shells were respectively 4.5±1.3 and 6.0±2.3% smaller at pHNBS~7.8 (pCO2~1100-1200 μatm) than at a control pHNBS of ~8.1 (pCO2~460-640 μatm). Moreover, a decrease of 12.0±5.4% of shell thickness was observed after 15d of development. More severe impacts were found with a decrease of ~0.5 pHNBS unit during the first 2 days of development which could be attributed to a decrease of calcification due to a slight undersaturation of seawater with respect to aragonite. Indeed, important effects on both hatching and D-veliger shell growth were found. Hatching rates were 24±4% lower while D-veliger shells were 12.7±0.9% smaller at pHNBS~7.6 (pCO2~1900 μatm) than at a control pHNBS of ~8.1 (pCO2~540 μatm). Although these results show that blue mussel larvae are still able to develop a shell in seawater undersaturated with respect to aragonite, the observed decreases of hatching rates and shell growth could lead to a significant decrease of the settlement success. As the environmental conditions considered in this study do not necessarily reflect the natural conditions experienced by this species at the time of spawning, future studies will need to consider the whole larval cycle (from fertilization to settlement) under environmentally relevant conditions in order to

  3. 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

  4. Predation of the ribbed mussel geukensia demissa by the blue crab callinectes sapidus

    NASA Astrophysics Data System (ADS)

    Seed, R.

    Callinectes sapidus fed extensively on Geukensia demissa in laboratory aquaria. Several predation techniques used by Callinectes to open its prey are reported. Prey value decreases monotonically with increasing mussel size. Crabs consumed mussels over a wide size range but were generally reluctant to feed on larger mussels whilst smaller, more profitably prey was available. The relative importance of 'energy maximization' and 'time minimization' could not be distinguished. The distribution and population structure of Geukensia at Beaufort, N. Carolina are briefly considered in terms of the foraging strategy of Callinectes.

  5. Specific congener profiles of polychlorinated dibenzo-p-dioxins and dibenzofurans in blue mussel in Osaka Bay in Japan: Aqueous solubilities of PCDDs and PCDFs

    SciTech Connect

    Miyata, Hideaki; Takayama, Koji; Mimura, Mayumi; Kashimoto, Takashi ); Fukushima, Shigehiko )

    1989-09-01

    The authors have monitored polychlorinated dibenzo-p-dioxins (PCDDs) and polychlorinated dibenzofurans (PCDFs) in the coastal waters of Japan by using blue mussel (Mytilus edulis) as a biological indicator. The levels of both chemicals were surmised to closely relate to the number of municipal incinerators and the population densities in the cities adjoining the sampling location. The main contamination source in Osaka Bay, which is heavy polluted with PCDDs and PCDFs, was determined to be the fly ash from municipal waste incinerators based upon analytical results of blue mussel from Osaka Bay sediments, sediments from Osaka Bay, and sediments from a river, which is located near a typical urban municipal waste incinerator. However, there was a remarkable difference in congener profiles of PCDDs and PCDFs between the blue mussel and the fly ash, that is, the mussel mainly contained tetraCDDs and tetraCDFs with congener ratios of 56 {plus minus} 9.7% and 62 {plus minus} 6.0%, respectively, whereas the fly ash contained the higher chlorinated PCDDs and PCDFs as major congeners. In this study, the specific congener profiles of PCDDs and PCDFs in blue mussel were investigated from the point of view of their water solubilities.

  6. Mitogenomics of southern hemisphere blue mussels (Bivalvia: Pteriomorphia): Insights into the evolutionary characteristics of the Mytilus edulis complex

    PubMed Central

    Gaitán-Espitia, Juan Diego; Quintero-Galvis, Julian F.; Mesas, Andres; D’Elía, Guillermo

    2016-01-01

    Marine blue mussels (Mytilus spp.) are widespread species that exhibit an antitropical distribution with five species occurring in the Northern Hemisphere (M. trossulus, M. edulis, M. galloprovincialis, M. californianus and M. coruscus) and three in the Southern Hemisphere (M. galloprovincialis, M. chilensis and M. platensis). Species limits in this group remain controversial, in particular for those forms that live in South America. Here we investigated structural characteristics of marine mussels mitogenomes, based on published F mtDNA sequences of Northern Hemisphere species and two newly sequenced South American genomes, one from the Atlantic M. platensis and another from the Pacific M. chilensis. These mitogenomes exhibited similar architecture to those of other genomes of Mytilus, including the presence of the Atp8 gene, which is missing in most of the other bivalves. Our evolutionary analysis of mitochondrial genes indicates that purifying selection is the predominant force shaping the evolution of the coding genes. Results of our phylogenetic analyses supported the monophyly of Pteriomorphia and fully resolved the phylogenetic relationships among its five orders. Finally, the low genetic divergence of specimens assigned to M. chilensis and M. platensis suggests that these South American marine mussels represent conspecific variants rather than distinct species. PMID:27241855

  7. Mitogenomics of southern hemisphere blue mussels (Bivalvia: Pteriomorphia): Insights into the evolutionary characteristics of the Mytilus edulis complex.

    PubMed

    Gaitán-Espitia, Juan Diego; Quintero-Galvis, Julian F; Mesas, Andres; D'Elía, Guillermo

    2016-01-01

    Marine blue mussels (Mytilus spp.) are widespread species that exhibit an antitropical distribution with five species occurring in the Northern Hemisphere (M. trossulus, M. edulis, M. galloprovincialis, M. californianus and M. coruscus) and three in the Southern Hemisphere (M. galloprovincialis, M. chilensis and M. platensis). Species limits in this group remain controversial, in particular for those forms that live in South America. Here we investigated structural characteristics of marine mussels mitogenomes, based on published F mtDNA sequences of Northern Hemisphere species and two newly sequenced South American genomes, one from the Atlantic M. platensis and another from the Pacific M. chilensis. These mitogenomes exhibited similar architecture to those of other genomes of Mytilus, including the presence of the Atp8 gene, which is missing in most of the other bivalves. Our evolutionary analysis of mitochondrial genes indicates that purifying selection is the predominant force shaping the evolution of the coding genes. Results of our phylogenetic analyses supported the monophyly of Pteriomorphia and fully resolved the phylogenetic relationships among its five orders. Finally, the low genetic divergence of specimens assigned to M. chilensis and M. platensis suggests that these South American marine mussels represent conspecific variants rather than distinct species. PMID:27241855

  8. Quality assessment of the blue mussel (Mytilus edulis): comparison between commercial and wild types.

    PubMed

    De Witte, B; Devriese, L; Bekaert, K; Hoffman, S; Vandermeersch, G; Cooreman, K; Robbens, J

    2014-08-15

    This study compared species identity, microplastics, chemical and microbial contamination between consumption mussels and wild type mussels, collected at Belgian department stores and Belgian groynes and quaysides, respectively. Species identification based on genetic analysis showed a high number of Mytilus (M.) edulis compared to M. galloprovincialis and M. edulis/galloprovincialis hybrid mussels. The number of total microplastics varied from 2.6 to 5.1 fibres/10 g of mussel. A higher prevalence of orange fibres at quaysides is related to fisheries activities. Chemical contamination of polycyclic aromatic hydrocarbons and polychlorobiphenyls could be related to industrial activities and water turbidity, with maximum concentrations at the quayside of port Zeebrugge. The inverse was noted for Escherichia coli contamination, which was relatively low at Zeebrugge quayside with a total count of 3.9 × 10(2)CFU/100 g tissue, due to limited agricultural effluents. Results of this complementary analysis stress the importance of integrated monitoring and quality assessment. PMID:24969855

  9. Does acute lead (Pb) contamination influence membrane fatty acid composition and freeze tolerance in intertidal blue mussels in arctic Greenland?

    PubMed

    Thyrring, Jakob; Juhl, Bodil Klein; Holmstrup, Martin; Blicher, Martin E; Sejr, Mikael K

    2015-11-01

    In their natural habitats, organisms are exposed to multiple stressors. Heavy metal contamination stresses the cell membrane due to increased peroxidation of lipids. Likewise, sub-zero air temperatures potentially reduce membrane functionality in ectothermal animals. We tested if acute lead (Pb) exposure for 7 days would influence survival in intertidal blue mussels (Mytilus edulis) after exposure to realistic sub-zero air temperatures. A full factorial experiment with five tissue Pb concentrations between 0 and 3500 μg Pb/g and six sub-zero temperatures from 0 to -17 °C were used to test the hypothesis that sub-lethal effects of Pb may increase the lethality caused by freezing in blue mussels exposed to temperatures simulating Greenland winter conditions. We found a significant effect of temperature on mortality. However, the short-term exposure to Pb did not result in any effects of Pb, nor did we find interactions between Pb and temperature. We analysed the relative abundance of major phospholipid fatty acids (PLFAs) in the gill tissue, but we found no significant effect of Pb tissue concentration on PLFA composition. Results suggest that Pb accumulation has limited effects on freeze tolerance and does not induce membrane damage in terms of persistent lipid peroxidation. PMID:26438355

  10. Identification and characterisation of a calcium carbonate-binding protein, blue mussel shell protein (BMSP), from the nacreous layer.

    PubMed

    Suzuki, Michio; Iwashima, Ai; Tsutsui, Naoaki; Ohira, Tsuyoshi; Kogure, Toshihiro; Nagasawa, Hiromichi

    2011-11-01

    The nacreous layer of molluscan shells consists of a highly organised, layered structure comprising calcium carbonate aragonite crystals, each surrounded by an organic matrix. In the Japanese pearl oyster Pinctada fucata, the Pif protein from the nacreous layer functions in aragonite binding, and plays a key role in nacre formation. Here, we investigated whether the blue mussel Mytilus galloprovincialis also has a protein with similar functions in the nacreous layer. By using a calcium carbonate-binding assay, we identified the novel protein blue mussel shell protein (BMSP) 100 that can bind calcium carbonate crystals of both aragonite and calcite. When the entire sequence of a cDNA encoding BMSP 100 was determined, it was found that BMSP is a preproprotein consisting of a signal peptide and two proteins, BMSP 120 and BMSP 100. BMSP 120 contains four von Willebrand factor A (VWA) domains and one chitin-binding domain, thus suggesting that it has a role in maintaining structure within the matrix. Immunohistochemical analysis revealed that BMSP 100 is present throughout the nacreous layer with dense localisation in the myostracum. Posttranslational modification analysis indicated that BMSP 100 is phosphorylated and glycosylated. These results suggest that there is a common molecular mechanism between P. fucata and M. galloprovincialis that underlies the nacreous layer formation. PMID:21932217

  11. Accumulation of copper, chromium, and arsenic in blue mussels (Mytilus edulis) from laboratory and field exposures to wood treated with chromated copper arsenate type C

    SciTech Connect

    Adler-Ivanbrook, L.; Breslin, V.T.

    1999-02-01

    Laboratory and field experiments were conducted to examine the uptake of Cu, Cr, and As leached from southern yellow pine (SYP) treated with chromated copper arsenate type C (CCA-C), as well as effects on mortality and growth, in blue mussels (Mytilus edulis). Mussels were exposed to CCA-C-treated wood at a preservative retention of 40 kg/m{sup 3} and control (nontreated) SYP in laboratory flow-through sea table and field exposure experiments for 9 months in 1994 and 3 months in 1995. Mussels were sampled at regular intervals to evaluate possible short- and long-term exposure effects., Individual mussels were measured to determine the length, dry weight, and condition index. Mussel tissues were than analyzed for Cu, Cr, and As. Results showed few significant differences in condition index, dry weight, and length between CCA-C-exposed and control mussels. In addition, no statistically significant differences in mortality were found between the mussels exposed to CCA-C-treated and nontreated SYP in the laboratory flow-through sea table and field exposure experiments. Significant differences in Cu, As, and Cr contents in mussel tissues between treatments were few, and generally cannot be attributed to exposure to CCA-C-treated SYP. The lack of Cu, Cr, and As uptake from CCA-C-treated SYP was attributed to the low, although continuous, rate of release of these elements from CCA-C-treated wood and to the experimental design, which allowed continuous flushing, prohibiting the accumulation of these elements in the water surrounding the mussels.

  12. Induction of apoptosis in the blue mussel Mytilus galloprovincialis by tri-n-butyltin chloride.

    PubMed

    Micić, M; Bihari, N; Labura, Z; Müller, W E; Batel, R

    2001-11-01

    Induction of apoptosis by tri-n-butyltin (TBT) in gill tissue of the mussel Mytilus galloprovincialis was investigated. The terminal dUTP nick-end labeling technique (TUNEL) was used to detect cells displaying DNA fragmentation within gill structures. Genomic DNA fragmentation was detected as characteristically ladder-like pattern of DNA fragments induced by single injection of different doses of TBT (1-5 microg/g) below the mantle, directly into the pallial fluid, after 24 h of incubation. DNA degradation of higher order DNA structure, as well as reduced G(0)/G(1) cell cycle region (the sub-G(1) region) was detectable after 1.5 h of TBT incubation. Presence of apoptotic cells in mussels' gills was indicated by the selective loss of G(2)/M cells concomitant with the appearance of cells with decreased DNA content in S and G(0)/G(1) cell cycle regions. The effect of the TBT on cell cycle in a mussel gill was a dose related and exposure time depending. The possible mechanism of induction of apoptosis in vivo in gill tissue of mussel treated with TBT is discussed. PMID:11551622

  13. Hydroxylated and methoxylated polybrominated diphenyl ethers in long-tailed ducks (Clangula hyemalis) and their main food, Baltic blue mussels (Mytilus trossulus × Mytilus edulis).

    PubMed

    Dahlberg, Anna-Karin; Chen, Vivian Lindberg; Larsson, Kjell; Bergman, Åke; Asplund, Lillemor

    2016-02-01

    Long-tailed ducks (Clangula hyemalis) that breed in northern Europe and western Siberia and commonly winter in the Baltic Sea, are threatened by a significant population decrease. The ducks are, by primarily feeding on Baltic blue mussels (Mytilus trossulus × Mytilus edulis) while wintering in the Baltic Sea, potentially subjected to high levels of toxic hydroxylated polybrominated diphenyl ethers (OH-PBDEs). To assess long-tailed ducks exposure to polybrominated phenols (PBPs), polybrominated anisoles (PBAs), hydroxylated polybrominated diphenyl ethers (OH-PBDEs), their methylated counterparts (MeO-PBDEs) and polybrominated diphenyl ethers (PBDEs), livers of ten long-tailed ducks wintering in the Baltic Sea were analysed. Pattern and levels of analytes in long-tailed ducks (liver) and blue mussels sampled in March and May at nine sites in the Baltic Sea were compared. The geometric mean concentration (ng/g l.w.) in livers of long-tailed ducks and Baltic blue mussels were: Σ(2)PBPs: 0.57 and 48; Σ(2)PBAs: 0.83 and 11; Σ(7)OH-PBDEs: 6.1 and 45; Σ(7)MeO-PBDEs: 3.8 and 69; Σ(7)PBDEs: 8.0 and 7.2, respectively. Based on an estimated daily intake of 450 g fresh blue mussel meat, long-tailed ducks daily dietary intake of brominated substances while foraging in the Baltic Sea in March-May was estimated to; 390 ng Σ(2)PBPs, 90 ng Σ(2)PBAs, 370 ng Σ(7)OH-PBDEs, 590 ng Σ(7)MeO-PBDEs and 59 ng Σ(7)PBDEs. The low levels of PBPs, PBAs, OH-PBDEs and MeO-PBDEs in the long-tailed duck livers compared to blue mussel, despite a continuous daily intake, suggest that these compounds are poorly retained in long-tailed ducks. PMID:26495833

  14. Associational resistance of fouled blue mussels (Mytilus edulis) against starfish (Asterias rubens) predation: relative importance of structural and chemical properties of the epibionts

    NASA Astrophysics Data System (ADS)

    Laudien, Jürgen; Wahl, Martin

    2004-10-01

    Several epibiotic species reduce starfish (Asterias rubens) preference for the blue mussel Mytilus edulis in the Baltic. The aim of this study was to reveal whether this associational resistance was caused by structural or chemical aspects of the different epibionts. To assess structural epibiont effects, an in situ experiment was conducted with unfouled mussels and mussels equipped with artificial epibionts (`dummies') exposed to natural predation by A. rubens. The chemically inert dummies closely matched the structural properties of the locally common epibionts Balanus improvisus (barnacle), Ceramium strictum (red alga), Halichondria panicea (sponge), and Laomedea flexuosa (hydrozoan). Starfish fed indiscriminately in all treatments. Chemical effects of epibionts on the attractiveness of mussels for A. rubens were investigated by incorporating freeze-dried epibionts or mussel tissue into Phytagel pellets at natural concentrations. Starfish were allowed to choose among these structurally similar but chemically different prey items in an in vitro experiment. The predators exhibited significant preferences among the food pellets, which closely matched their preferences for corresponding natural mussel-epibiont associations. Thus, chemical aspects of epibionts appear to play a larger role in this associational resistance than do structural aspects. Implications of these indirect interactions for benthic communities are discussed.

  15. Comparison of nonplanar and coplanar PCB congener partitioning in seawater and bioaccumulation in blue mussels (Mytilus edulis)

    SciTech Connect

    Bergen, B.J.; Nelson, W.G.; Pruell, R.J.

    1996-09-01

    The partitioning of 18 nonplanar and three coplanar polychlorinated biphenyl (PCB) congeners was quantified in New Bedford Harbor, Massachusetts. Concurrently, bioaccumulation of these congeners was measured in blue mussels deployed for 7 and 28 d in New Bedford Harbor, and bioconcentration factors (BCFs) were calculated for each congener. The PCB concentrations measured in the dissolved and particulate fractions of seawater samples were used to calculate partition coefficients (K{sub p}) for each congener. These values were correlated with reported octanol/water partition coefficients (K{sub ow}). No significant differences (p > 0.05) were observed in the relationships between K{sub p} and K{sub ow} for the coplanar congeners relative to the nonplanar congeners. Coplanar congeners reached steady state faster than the nonplanar congeners; however, after 28 d a similar relationship was observed between BCF and K{sub ow} in coplanar and nonplanar congeners. These data indicate that coplanar PCBs partition in seawater and accumulate in mussels similarly to nonplanar PCBs with the same number of chlorines.

  16. Physiological performance and general histology of the blue mussel, Mytilus edulis L., from the Baltic and North seas

    NASA Astrophysics Data System (ADS)

    Gilek, Michael; Tedengren, Michael; Kautsky, Nils

    A physiological approach has been proposed for studying the ecological consequences of diseases and parasitism in bivalve molluscs. We investigated effects of some naturally occurring non-lethal parasites and histological changes in the blue mussel, Mytilus edulis L., on some commonly used bivalve condition indices, viz the oxygen:nitrogen ratio, the scope for growth and the body condition index. We found no correlation between these physiological condition indices, which implies that an individual can be classified as in 'good condition' according to e.g. the O:N ratio and the body condition index, while at the same time this mussel may have a low scope for growth indicating a stressed status. This is probably because the O:N ratio, the scope for growth and the body condition index integrate metabolic processes over different periods of time. No general deleterious effects on these condition indices could be detected either due to parasitic infestation or general histological changes. Hence, it was not possible to translate detrimental effects of histological conditions directly into energy equivalents.

  17. First record of the green microalgae Coccomyxa sp. in blue mussel Mytilus edulis (L.) from the Lower St. Lawrence Estuary (Québec, Canada).

    PubMed

    Zuykov, Michael; Belzile, Claude; Lemaire, Nicolas; Gosselin, Michel; Dufresne, France; Pelletier, Emilien

    2014-07-01

    During autumn 2012 and spring 2013, blue mussels Mytilus edulis (L.) with strongly deformed (L-shaped) posterior shell margins and green spots in soft tissue (microalgae) were collected from intertidal zone along the south shore of the Lower St. Lawrence Estuary near Rimouski (Québec, Canada). Identification of algal cells infesting mussels as Coccomyxa sp. was confirmed by rRNA sequencing and HPLC pigment analysis. Flow cytometric analysis revealed the presence of algal cells in the hemolymph and extrapallial fluid in mussels with deformed and non-deformed shells; concentrations of algal cells were ranged from about 200mL(-1) in mussels with actually non-deformed shells to concentrations reaching up to 3.8×10(7)mL(-1) in mussels with heavily deformed ones. Chemical analyses of soft tissues led us to conclude that butyltin compounds and trace metals cannot be considered among factors responsible for the shell deformity observed. Using scanning electron microscopy, the biogenic nature of the erosion on the external shell surface and aragonitic lenses of prisms in the curvature zone of deformed shells (in sections) were recorded. The sequence of the green algae from M. edulis of the Lower St. Lawrence Estuary was closely related to Coccomyxa sp. infecting M. edulis from the Flensburg Fjord (North Sea) and Modiolus modiolus (L.) from the Vityaz Bay (Sea of Japan). PMID:24837974

  18. Small is profitable: No support for the optimal foraging theory in sea stars Asterias rubens foraging on the blue edible mussel Mytilus edulis

    NASA Astrophysics Data System (ADS)

    Hummel, Christiaan; Honkoop, Pieter; van der Meer, Jaap

    2011-07-01

    Doubt has been shed recently on the most popular optimal foraging theory stating that predators should maximize prey profitability, i.e., select that prey item that contains the highest energy content per handling time. We hypothesized that sea stars do not forage on blue mussels according to the classical optimal foraging theory but are actively avoiding damage that may be caused by e.g. capture of foraging on too-strong mussel shells, hence the sea stars will have a stronger preference for mussels that are smaller than the most profitable ones. Here we present experimental evidence of the sea star Asterias rubens as a predator that indeed chooses much smaller blue mussels Mytilus edulis to forage on than the most profitable ones. Hence this study does not support the optimal foraging theory. There may be other constraints involved in foraging than just optimizing energy intake, for example predators may also be concerned with preventing potential loss or damage of their foraging instruments.

  19. Mussel Glue

    NASA Technical Reports Server (NTRS)

    1987-01-01

    A mytilus edilus, a common blue ocean mussel is attaching itself to the underside of a wet glass in a laboratory. It secretes a glue like substance in the form of multiple threads which attach to surfaces such as shells, rocks, piers and ships. This natural super glue hardens within minutes and tightly affixes to its selected platform even in the roughest seas. Its superior adhesive properties suggest many practical applications. One company, Bio-Polymers, Inc., has developed a synthetic mussel glue for the commercial market.

  20. Growth of farmed blue mussels ( Mytilus edulis L.) in a Norwegian coastal area; comparison of food proxies by DEB modeling

    NASA Astrophysics Data System (ADS)

    Handå, Aleksander; Alver, Morten; Edvardsen, Christian Vik; Halstensen, Stein; Olsen, Anders Johny; Øie, Gunvor; Reitan, Kjell Inge; Olsen, Yngvar; Reinertsen, Helge

    2011-11-01

    Seston variables and growth of the blue mussel ( Mytilus edulis L.) were measured during the growth season from March to October in three suspended longline farms in Central Norway; one in the inner part of Åfjorden (63° 56' N, 10° 11' E) and two in Inner and Outer Koet, respectively (63° 49' N, 9° 42' and 47' E). Four seston variables were used as alternative input values in a Dynamic Energy Budget (DEB) model to compare their suitability as food proxies for predicting mussel growth: 1; total particulate matter (TPM), 2; particulate organic matter (POM), 3; organic content (OC) and 4; chlorophyll a (chl a). Mean TPM and POM measured 6.1 and 1.9 mg L - 1 in Åfjorden, 10.3 and 4.2 mg L - 1 in Inner Koet, and 10.5 and 4.6 mg L - 1 in Outer Koet, respectively, resulting in a mean OC of 32, 41 and 44% in Åfjorden and Inner and Outer Koet, respectively. Mean chl a measured 1.6 μg L - 1 in Åfjorden, 3.1 μg L - 1 in Inner Koet, and 1.6 μg L - 1 in Outer Koet. Average length growth was 0.20% day - 1 in medium sized mussels (24-36 mm) in Åfjorden and 0.08% day - 1 in large mussels (40-55 mm) in Inner and Outer Koet. Mean standardized soft tissue dry weight ranged between 250 and 390 mg in Åfjorden, 600 and 1175 in Inner Koet, and 600 and 960 mg in Outer Koet, and showed a seasonal pattern independent of growth in length with scattered spawnings. The model showed the best match for a single criterion for growth in both length and soft tissue dry weight for different food proxies depending on location. TPM gave the best match in Åfjorden, while chl a and POM gave the best match in Inner and Outer Koet, respectively. For Åfjorden, growth in length decreased markedly at the end of the sampling period, and this decrease was not reproduced by the model for any of the food proxies. For Inner and Outer Koet, agreement between measured and modeled length was quite good for the optimal choices of food proxy, with clear variations between the proxies for both farms. The

  1. Does the marine biotoxin okadaic acid cause DNA fragmentation in the blue mussel and the pacific oyster?

    PubMed

    McCarthy, Moira; O'Halloran, John; O'Brien, Nora M; van Pelt, Frank F N A M

    2014-10-01

    Two bivalve species of global economic importance: the blue mussel, Mytilus edulis and the pacific oyster, Crassostrea gigas were exposed in vivo, to the diarrhoetic shellfish toxin okadaic acid (OA), and impacts on DNA fragmentation were measured. Shellfish were exposed using two different regimes, the first was a single (24 h) exposure of 2.5 nM OA (∼0.1 μg/shellfish) and algal feed at the beginning of the trial (T0), after which shellfish were only fed algae. The second was daily exposure of shellfish to two different concentrations of OA mixed with the algal feed over 7 days; 1.2 nM OA (∼0.05 μg OA/shellfish/day) and 50 nM OA (∼2 μg OA/shellfish/day). Haemolymph and hepatopancreas cells were extracted following 1, 3 and 7 days exposure. Cell viability was measured using the trypan blue exclusion assay and remained above 85% for both cell types. DNA fragmentation was examined using the single-cell gel electrophoresis (comet) assay. A significant increase in DNA fragmentation was observed in the two cell types from both species relative to the controls. This increase was greater in the pacific oyster at the higher toxin concentration. However, there was no difference in the proportion of damage measured between the two cell types, and a classic dose response was not observed, increasing toxin concentration did not correspond to increased DNA fragmentation. PMID:25440785

  2. Organochlorine contaminants in coastal marine ecosystems of southern Alaska: inferences from spatial patterns in blue mussels (Mytilus trossulus).

    PubMed

    Reese, Stacey L; Estes, James A; Jarman, Walter M

    2012-08-01

    We measured the concentrations and chemical structures of persistent organochlorines (OCs) in blue mussels (Mytilus trossulus) from 44 sites across southwest and southeast Alaska in an effort to determine both the sources of these compounds and the extent to which this region might be contaminated. High PCB concentrations were detected at Amchitka, Adak, and Unalaska Islands (83, 430, and 2800μgkg(-1) dry weight, respectively) in the Aleutians with relatively low concentrations elsewhere (7.1-51μgkg(-1) dry weight). Heavy PCB congener profiles (indicative of localized point sources) characterized the high concentration sites whereas distinctly lighter congener profiles (indicative of atmospheric transport) characterized the lower concentration sites. Elevated PCB concentrations at Adak were restricted to a small area along the island's eastern shore, suggesting either limited dispersion or rapid dilution of these compounds. More uniform chlorinated pesticide concentrations among the collection sites suggests that these compounds are entering the Aleutian ecosystem from distant sources. Pesticide concentrations correlated significantly with seabird density across the islands we sampled, thus identifying biological transport as a delivery mechanism of these compounds to the Aleutian archipelago. Our findings do not implicate persistent organochlorines as a significant factor in the recent pinniped and sea otter population declines across southwest Alaska. PMID:22579453

  3. endo-beta-1,4-Mannanases from blue mussel, Mytilus edulis: purification, characterization, and mode of action.

    PubMed

    Xu, Bingze; Hägglund, Per; Stålbrand, Henrik; Janson, Jan-Christer

    2002-01-18

    Two variants of an endo-beta-1,4-mannanase from the digestive tract of blue mussel, Mytilus edulis, were purified by a combination of immobilized metal ion affinity chromatography, size exclusion chromatography in the absence and presence of guanidine hydrochloride and ion exchange chromatography. The purified enzymes were characterized with regard to enzymatic properties, molecular weight, isoelectric point, amino acid composition and N-terminal sequence. They are monomeric proteins with molecular masses of 39216 and 39265 Da, respectively, as measured by MALDI-TOF mass spectrometry. The isoelectric points of both enzymes were estimated to be around 7.8, however slightly different, by isoelectric focusing in polyacrylamide gel. The enzymes are stable from pH 4.0 to 9.0 and have their maximum activities at a pH about 5.2. The optimum temperature of both enzymes is around 50-55 degrees C. Their stability decreases rapidly when going from 40 to 50 degrees C. The N-terminal sequences (12 residues) were identical for the two variants. They can be completely renatured after denaturation in 6 M guanidine hydrochloride. The enzymes readily degrade the galactomannans from locust bean gum and ivory nut mannan but show no cross-specificity for xylan and carboxymethyl cellulose. There is no binding ability observed towards cellulose and mannan. PMID:11689251

  4. A new approach for the assessment of stochastic variation: analysis of behavioural response in blue mussel ( Mytilus edulis L.)

    NASA Astrophysics Data System (ADS)

    Lajus, D. L.; Sukhotin, A. A.

    1998-06-01

    One of the most effective techniques for evaluating stress is the analysis of developmental stability, measured by stochastic variation based particularly on fluctuating asymmetry, i.e. a variance in random deviations from perfect bilateral symmetry. However, the application of morphological methods is only possible when an organism lives under testing conditions during a significant part of its ontogenesis. Contrary to morphological characters, behavior can change very fast. Consequently, methods based on behavioural characters may have advantages over more traditional approaches. In this study we describe the technique of assessing stochastic variation, using not morphological, but behavioural characters. To measure stochastic variation of behavioural response, we assessed the stability of the isolation reaction of blue mussel Mytilus edulis at regular changes of salinity. With increasing temperature from +12°C to +20°C stochastic variation of the isolation reaction increased, which is a common response to change of environmental conditions. In this way, we have developed a method of assessing stochastic variation of behavioural response in molluscs. This method may find a great range of applications, because its usage does not require keeping animals in tested conditions for a long time.

  5. Effects of Black Rock Harbor dredged material on the scope for growth of the blue mussel, Mytilus edulis, after laboratory and field exposures

    SciTech Connect

    Nelson, W.G.; Phelps, D.K.; Galloway, W.B.; Rogerson, P.F.; Pruell, R.J.

    1987-01-01

    A study was conducted to investigate residue-effect relationships between tissue residue concentrations and the scope for growth of the blue mussel, Mytilus edulis, after exposure in the laboratory and the field to dredged material from Black Rock Harbor (BRH), Bridgeport, Connecticut. A second objective included field verification of the laboratory results. Residue concentrations in mussels, particularly stable compounds such as polychlorinated biphenyls, were found to be closely related to exposure concentration. Scope for growth, clearance rates, and shell growth measurements were inversely related to BRH exposure and subsequent tissue residues, with concentration as low as 1.5 mg/L of BRH material causing negative biological effects. In the field, mussels were placed along a transect from the center of the disposal mound to a clean area distant from the disposal mound. Exposure estimates indicated that the maximum concentration BRH material occurred during the disposal operation, after which both exposure and tissue residue concentrations decreased dramatically. Of the measurements made at the four field stations during the course of the study, a reduction in the scope for growth of mussels, attributable to BRH material, was observed only once. The estimated concentration of BRH suspended material during that collection was very close to the lowest concentration affecting the scope for growth in the laboratory experiments. 33 refs., 30 figs., 17 tabs.

  6. The impact of TiO2 nanoparticles on uptake and toxicity of benzo(a)pyrene in the blue mussel (Mytilus edulis).

    PubMed

    Farkas, J; Bergum, S; Nilsen, E W; Olsen, A J; Salaberria, I; Ciesielski, T M; Bączek, T; Konieczna, L; Salvenmoser, W; Jenssen, B M

    2015-04-01

    Nanoparticles are emerging contaminants of concern. Knowledge on their environmental impacts is scarce, especially on their interactive effects with other contaminants. In this study we investigated effects of titanium dioxide nanoparticles (TiO2NP) on the blue mussel (Mytilus edulis) and determined their influence on the bioavailability and toxicity of benzo(a)pyrene (B(a)P), a carcinogenic polyaromatic hydrocarbon (PAH). Blue mussels were exposed to either TiO2NP (0.2 and 2.0 mg L(-1)) or B(a)P (20 μg L(-1)) and to the respective combinations of these two compounds. Aqueous contaminant concentrations, the uptake of Ti and B(a)P into mussel soft tissue, effects on oxidative stress and chromosomal damage were analyzed. The uncoated TiO2NP agglomerated rapidly in the seawater. The presence of TiO2NP significantly reduced the bioavailability of B(a)P, shown by lowered B(a)P concentrations in exposure tanks and in mussel tissue. The activities of antioxidant enzyme superoxide dismutase (SOD), catalase (CAT) and glutathione peroxidase (GPx) were impacted by the various exposure regimes, indicating oxidative stress in the contaminant exposure groups. While SOD activity was increased only in the 0.2TiO2NP exposure group, CAT activity was enhanced in both combined exposure groups. The GPx activity was increased only in the groups exposed to the two single compounds. In hemocytes, increased chromosomal damage was detected in mussels exposed to the single compounds, which was further increased after exposure to the combination of compounds. In this study we show that the presence of TiO2NP in the exposure system reduced B(a)P uptake in blue mussels. However, since most biomarker responses did not decrease despite of the lower B(a)P uptake in combined exposures, the results suggest that TiO2NP can act as additional stressor, or potentially alters B(a)P toxicity by activation. PMID:25574974

  7. Transcriptomic responses to salinity stress in invasive and native blue mussels (genus Mytilus).

    PubMed

    Lockwood, Brent L; Somero, George N

    2011-02-01

    The invasive marine mussel Mytilus galloprovincialis has displaced the native congener Mytilus trossulus from central and southern California, but the native species remains dominant at more northerly sites that have high levels of freshwater input. To determine the extent to which interspecific differences in physiological tolerance to low salinity might explain limits to the invasive species' biogeography, we used an oligonucleotide microarray to compare the transcriptional responses of these two species to an acute decrease in salinity. Among 6777 genes on the microarray, 117 genes showed significant changes that were similar between species, and 12 genes showed significant species-specific responses to salinity stress. Osmoregulation and cell cycle control were important aspects of the shared transcriptomic response to salinity stress, whereas the genes with species-specific expression patterns were involved in mRNA splicing, polyamine synthesis, exocytosis, translation, cell adhesion, and cell signalling. Forty-five genes that changed expression significantly during salinity stress also changed expression during heat stress, but the direction of change in expression was typically opposite for the two forms of stress. These results (i) provide insights into the role of changes in gene expression in establishing physiological tolerance to acute decreases in salinity, and (ii) indicate that transcriptomic differences between M. galloprovincialis and M. trossulus in response to salinity stress are subtle and involve only a minor fraction of the overall suite of gene regulatory responses. PMID:21199031

  8. Distribution and elimination of (/sup 14/C)octachlorostyrene in cod (Gadus morhua), rainbow trout (Salmo gairdneri, and blue mussel (Mytilus edulis)

    SciTech Connect

    Ingebrigtsen, K.; Solbakken, J.E.; Norheim, G.; Nafstad, I.

    1988-01-01

    Cod (Gadus morhua) and rainbow trout (Salmo gairdneri) were given a single oral dose of 100 microCi/kg b.w. of (/sup 14/C)octachlorostyrene ((/sup 14/C)OCS) in peanut oil. Blue mussel (Mytilus edulis) was exposed to (/sup 14/C)OCS in water. The distribution and elimination of the compound was studied by liquid scintillation counting and whole-body autoradiography. The highest degree of radioactivity in the cod and rainbow trout was measured in the liver and the visceral fat, respectively. The degree of radioactivity in the brain of cod exceeded that of the rainbow trout by a factor between 2 and 4 at all survival times. In addition to bile excretion of (/sup 14/C)OCS-derived radioactivity, a possible excretion over the intestinal mucosa was suggested. The rate of elimination was slow in both species, and substantial amounts of radioactivity remained in the tissues 90 d after administration. In the blue mussel, the highest degree of radioactivity was found in the hepatopancreas. Substantial amounts of radioactivity were present in the mussel tissues 60 d after administration.

  9. High Pressure Inactivation of HAV within Mussels

    Technology Transfer Automated Retrieval System (TEKTRAN)

    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...

  10. Proteomics of hyposaline stress in blue mussel congeners (genus Mytilus): implications for biogeographic range limits in response to climate change.

    PubMed

    Tomanek, Lars; Zuzow, Marcus J; Hitt, Lauren; Serafini, Loredana; Valenzuela, Jacob J

    2012-11-15

    Climate change is affecting species' physiology, pushing environmental tolerance limits and shifting distribution ranges. In addition to temperature and ocean acidification, increasing levels of hyposaline stress due to extreme precipitation events and freshwater runoff may be driving some of the reported recent range shifts in marine organisms. Using two-dimensional gel electrophoresis and tandem mass spectrometry, we characterized the proteomic responses of the cold-adapted blue mussel Mytilus trossulus, a native to the Pacific coast of North America, and the warm-adapted M. galloprovincialis, a Mediterranean invader that has replaced the native from the southern part of its range, but may be limited from expanding north due to hyposaline stress. After exposing laboratory-acclimated mussels for 4 h to two different experimental treatments of hyposaline conditions and one control treatment (24.5, 29.8 and 35.0 psu, respectively) followed by a 0 and 24 h recovery at ambient salinity (35 psu), we detected changes in the abundance of molecular chaperones of the endoplasmic reticulum (ER), indicating protein unfolding, during stress exposure. Other common responses included changes in small GTPases of the Ras superfamily during recovery, which suggests a role for vesicle transport, and cytoskeletal adjustments associated with cell volume, as indicated by cytoskeletal elements such as actin, tubulin, intermediate filaments and several actin-binding regulatory proteins. Changes of proteins involved in energy metabolism and scavenging of reactive oxygen species suggest a reduction in overall energy metabolism during recovery. Principal component analyses of protein abundances suggest that M. trossulus is able to respond to a greater hyposaline challenge (24.5 psu) than M. galloprovincialis (29.8 psu), as shown by changing abundances of proteins involved in protein chaperoning, vesicle transport, cytoskeletal adjustments by actin-regulatory proteins, energy metabolism and

  11. Comparative effects of the blue green algae Nodularia spumigena and a lysed extract on detoxification and antioxidant enzymes in the green lipped mussel (Perna viridis).

    PubMed

    Davies, Warren R; Siu, William H L; Jack, Ralph W; Wu, Rudolf S S; Lam, Paul K S; Nugegoda, Dayanthi

    2005-01-01

    Nodularia spumigena periodically proliferates to cause toxic algal blooms with some aquatic animals enduring and consuming high densities of the blue green algae or toxic lysis. N. spumigena contains toxic compounds such as nodularin and lipopolysaccharides. This current work investigates physiological effects of exposure from bloom conditions of N. spumigena cells and a post-bloom lysis. Biochemical and antioxidative biomarkers were comparatively studied over an acute 3-day exposure. In general, a post-bloom N. spumigena lysis caused opposite physiological responses to bloom densities of N. spumigena. Specifically, increases in glutathione (GSH) and glutathione peroxidase (GPx) and decreases in glutathione S-transferase (GST) were observed from the N. spumigena lysis. In contrast, N. spumigena cell densities decreased GSH and increased GST and lipid peroxidation (LPO) in mussels. Findings also suggest that at different stages of a toxic bloom, exposure may result in toxic stress to specific organs in the mussel. PMID:16291202

  12. Sex-related differences in steroid concentrations in the blue mussel (Mytilus edulis trossulus) from the southern Baltic Sea.

    PubMed

    Zabrzańska, Sandra; Smolarz, Katarzyna; Hallmann, Anna; Konieczna, Lucyna; Bączek, Tomasz; Wołowicz, Maciej

    2015-05-01

    This paper reports on sex-related differences in free steroid hormone concentrations including the concentrations of three naturally occurring estrogens (17β-estradiol E2, estrone E1, and estriol E3) and one androgen (testosterone T) in the tissues (gills and gonads) of the blue mussel Mytilus edulis trossulus sampled from the Gulf of Gdańsk (Baltic Sea, Poland). The dissimilarity in steroid concentrations between tissues was particularly evident in the T concentration with a level in gills almost three times higher compared to gonads (on average, 15.38 ng/g w.w. and 5.31 ng/g w.w., respectively, p=0.00008), suggesting its exogenous origin. In general, a tendency towards a skewed steroid profile related to sex, with E2 more abundant for males and T for females, was observed. Female gonads were characterized by a higher level of T than testis (4.61 ng/g w.w. for females and 0.70 ng/g w.w. for males, p=0.0121). At the same time, the level of E2 found in the testis was higher than in the ovary (4.81 ng/g w.w. and 3.86 ng/g w.w., respectively); however, the difference was not statistically significant. As for gills, similar trend with T and E2 being more abundant in males was observed. At the same time, no disturbances in the sex ratio and gametogenesis process were observed which suggests i) efficient deactivation of free forms of steroids, and/or ii) their little or no physiological role. PMID:25536333

  13. Genetic, Ecological and Morphological Distinctness of the Blue Mussels Mytilus trossulus Gould and M. edulis L. in the White Sea.

    PubMed

    Katolikova, Marina; Khaitov, Vadim; Väinölä, Risto; Gantsevich, Michael; Strelkov, Petr

    2016-01-01

    Two blue mussel lineages of Pliocene origin, Mytilus edulis (ME) and M. trossulus (MT), co-occur and hybridize in several regions on the shores of the North Atlantic. The two species were distinguished from each other by molecular methods in the 1980s, and a large amount of comparative data on them has been accumulated since that time. However, while ME and MT are now routinely distinguished by various genetic markers, they tend to be overlooked in ecological studies since morphological characters for taxonomic identification have been lacking, and no consistent habitat differences between lineages have been reported. Surveying a recently discovered area of ME and MT co-occurrence in the White Sea and employing a set of allozyme markers for identification, we address the issue whether ME and MT are true biological species with distinct ecological characteristics or just virtual genetic entities with no matching morphological and ecological identities. We find that: (1) in the White Sea, the occurrence of MT is largely concentrated in harbors, in line with observations from other subarctic regions of Europe; (2) mixed populations of ME and MT are always dominated by purebred individuals, animals classified as hybrids constituting only ca. 18%; (3) in terms of shell morphology, 80% of MT bear a distinct uninterrupted dark prismatic strip under the ligament while 97% of ME lack this character; (4) at sites of sympatry MT is more common on algal substrates while ME mostly lives directly on the bottom. This segregation by the substrate may contribute to maintaining reproductive isolation and decreasing competition between taxa. We conclude that while ME and MT are not fully reproductively isolated, they do represent clearly distinguishable biological, ecological and morphological entities in the White Sea. It remains to be documented whether the observed morphological and ecological differences are of a local character, or whether they have simply been overlooked in

  14. Genetic, Ecological and Morphological Distinctness of the Blue Mussels Mytilus trossulus Gould and M. edulis L. in the White Sea

    PubMed Central

    Katolikova, Marina; Khaitov, Vadim; Väinölä, Risto; Gantsevich, Michael; Strelkov, Petr

    2016-01-01

    Two blue mussel lineages of Pliocene origin, Mytilus edulis (ME) and M. trossulus (MT), co-occur and hybridize in several regions on the shores of the North Atlantic. The two species were distinguished from each other by molecular methods in the 1980s, and a large amount of comparative data on them has been accumulated since that time. However, while ME and MT are now routinely distinguished by various genetic markers, they tend to be overlooked in ecological studies since morphological characters for taxonomic identification have been lacking, and no consistent habitat differences between lineages have been reported. Surveying a recently discovered area of ME and MT co-occurrence in the White Sea and employing a set of allozyme markers for identification, we address the issue whether ME and MT are true biological species with distinct ecological characteristics or just virtual genetic entities with no matching morphological and ecological identities. We find that: (1) in the White Sea, the occurrence of MT is largely concentrated in harbors, in line with observations from other subarctic regions of Europe; (2) mixed populations of ME and MT are always dominated by purebred individuals, animals classified as hybrids constituting only ca. 18%; (3) in terms of shell morphology, 80% of MT bear a distinct uninterrupted dark prismatic strip under the ligament while 97% of ME lack this character; (4) at sites of sympatry MT is more common on algal substrates while ME mostly lives directly on the bottom. This segregation by the substrate may contribute to maintaining reproductive isolation and decreasing competition between taxa. We conclude that while ME and MT are not fully reproductively isolated, they do represent clearly distinguishable biological, ecological and morphological entities in the White Sea. It remains to be documented whether the observed morphological and ecological differences are of a local character, or whether they have simply been overlooked in

  15. Does natural selection explain the fine scale genetic structure at the nuclear exon Glu-5′ in blue mussels from Kerguelen?

    PubMed Central

    Gérard, Karin; Roby, Charlotte; Bierne, Nicolas; Borsa, Philippe; Féral, Jean-Pierre; Chenuil, Anne

    2015-01-01

    The Kerguelen archipelago, isolated in the Southern Ocean, shelters a blue mussel Mytilus metapopulation far from any influence of continental populations or any known hybrid zone. The finely carved coast leads to a highly heterogeneous habitat. We investigated the impact of the environment on the genetic structure in those Kerguelen blue mussels by relating allele frequencies to habitat descriptors. A total sample comprising up to 2248 individuals from 35 locations was characterized using two nuclear markers, mac-1 and Glu-5′, and a mitochondrial marker (COI). The frequency data from 9 allozyme loci in 9 of these locations were also reanalyzed. Two other nuclear markers (EFbis and EFprem's) were monomorphic. Compared to Northern Hemisphere populations, polymorphism in Kerguelen blue mussels was lower for all markers except for the exon Glu-5′. At Glu-5′, genetic differences were observed between samples from distinct regions (FCT = 0.077), as well as within two regions, including between samples separated by <500 m. No significant differentiation was observed in the AMOVA analyses at the two other markers (mac-1 and COI). Like mac-1, all allozyme loci genotyped in a previous publication, displayed lower differentiation (Jost's D) and FST values than Glu-5′. Power simulations and confidence intervals support that Glu-5′ displays significantly higher differentiation than the other loci (except a single allozyme for which confidence intervals overlap). AMOVA analyses revealed significant effects of the giant kelp Macrocystis and wave exposure on this marker. We discuss the influence of hydrological conditions on the genetic differentiation among regions. In marine organisms with high fecundity and high dispersal potential, gene flow tends to erase differentiation, but this study showed significant differentiation at very small distance. This may be explained by the particular hydrology and the carved coastline of the Kerguelen archipelago, together with

  16. Understanding Marine Mussel Adhesion

    SciTech Connect

    H. G. Silverman; F. F. Roberto

    2007-12-01

    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 waterimpervious 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.

  17. Understanding marine mussel adhesion.

    PubMed

    Silverman, Heather G; 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

  18. 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

  19. The development and implementation of a method using blue mussels (Mytilus spp.) as biosentinels of Cryptosporidium spp. and Toxoplasma gondii contamination in marine aquatic environments.

    PubMed

    Staggs, Sarah E; Keely, Scott P; Ware, Michael W; Schable, Nancy; See, Mary Jean; Gregorio, Dominic; Zou, Xuan; Su, Chunlei; Dubey, J P; Villegas, Eric N

    2015-12-01

    Surveillance monitoring for microbial water quality typically involves collecting single discrete grab samples for analyzing only one contaminant. While informative, current approaches suffer from poor recoveries and only provide a limited snapshot of the microbial contaminants only at the time of collection. To overcome these limitations, bivalves have been proposed as effective biosentinels of water quality particularly for their ability to efficiently concentrate and retain microbial contaminants for long periods of time. In this study, we examined the use of indigenous blue mussels (Mytilus spp.) as biosentinels to monitor for the presence of Toxoplasma gondii and Cryptosporidium water. An efficient method to extract oocyst DNA from various mussel tissues followed by PCR-based detection of these pathogens was developed, which resulted in the detection down to 10 oocysts. This method was then used to conduct a small survey in Point Lobos and Morro Bay, California to determine prevalence T. gondii and Cryptosporidium. Results revealed that mussels from Morro Bay were contaminated with T. gondii (33 %), while mussels from Point Lobos were contaminated with T. gondii (54 %) and Cryptosporidium (26.9 %) oocysts. Phylogenetic analysis using the SSU rRNA gene identified two novel Cryptosporidium parvum-like genotypes. Overall, this study demonstrated the application of using native California Mytilus spp. as biosentinels for pathogen contamination along the central California shorelines. More importantly, T. gondii and Cryptosporidium were found at higher prevalence rates in Morro Bay and in Point Lobos, an area not previously reported to be contaminated with these pathogens. PMID:26358104

  20. The Influence of Organic Material and Temperature on the Burial Tolerance of the Blue Mussel, Mytilus edulis: Considerations for the Management of Marine Aggregate Dredging

    PubMed Central

    Cottrell, Richard S.; Black, Kenny D.; Hutchison, Zoë L.; Last, Kim S.

    2016-01-01

    Rationale and Experimental Approach Aggregate dredging is a growing source of anthropogenic disturbance in coastal UK waters and has the potential to impact marine systems through the smothering of benthic fauna with organically loaded screening discards. This study investigates the tolerance of the blue mussel, Mytilus edulis to such episodic smothering events using a multi-factorial design, including organic matter concentration, temperature, sediment fraction size and duration of burial as important predictor variables. Results and Discussion Mussel mortality was significantly higher in organically loaded burials when compared to control sediments after just 2 days. Particularly, M. edulis specimens under burial in fine sediment with high (1%) concentrations of organic matter experienced a significantly higher mortality rate (p<0.01) than those under coarse control aggregates. Additionally, mussels exposed to the summer maximum temperature treatment (20°C) exhibited significantly increased mortality (p<0.01) compared to those in the ambient treatment group (15°C). Total Oxygen Uptake rates of experimental aggregates were greatest (112.7 mmol m-2 day-1) with 1% organic loadings in coarse sediment at 20°C. Elevated oxygen flux rates in porous coarse sediments are likely to be a function of increased vertical migration of anaerobically liberated sulphides to the sediment-water interface. However, survival of M. edulis under bacterial mats of Beggiatoa spp. indicates the species’ resilience to sulphides and so we propose that the presence of reactive organic matter within the burial medium may facilitate bacterial growth and increase mortality through pathogenic infection. This may be exacerbated under the stable interstitial conditions in fine sediment and increased bacterial metabolism under high temperatures. Furthermore, increased temperature may impose metabolic demands upon the mussel that cannot be met during burial-induced anaerobiosis. Summary Lack of

  1. Carcinogenicity of Black Rock Harbor sediment to the eastern oyster and trophic transfer of Black Rock Harbor carcinogens from the blue mussel to the winter flounder.

    PubMed Central

    Gardner, G R; Yevich, P P; Harshbarger, J C; Malcolm, A R

    1991-01-01

    The eastern oyster (Crassostrea virginica) developed neoplastic disorders when experimentally exposed both in the laboratory and field to chemically contaminated sediment from Black Rock Harbor (BRH), Bridgeport, Connecticut. Neoplasia was observed in oysters after 30 and 60 days of continuous exposure in a laboratory flow-through system to a 20 mg/L suspension of BRH sediment plus postexposure periods of 0, 30, or 60 days. Composite tumor incidence was 13.6% (49 neoplasms in 40, n = 295) for both exposures. Tumor occurrence was highest in the renal excretory epithelium, followed in order by gill, gonad, gastrointestinal, heart, and embryonic neural tissue. Regression of experimental neoplasia was not observed when the stimulus was discontinued. In field experiments, gill neoplasms developed in oysters deployed in cages for 30 days at BRH and 36 days at a BRH dredge material disposal area in Central Long Island Sound, and kidney and gastrointestinal neoplasms developed in caged oysters deployed 40 days in Quincy Bay, Boston Harbor. Oysters exposed to BRH sediment in the laboratory and in the field accumulated high concentrations of polychlorinated biphenyls (PCBs), polyaromatic hydrocarbons (PAHs), and chlorinated pesticides. Chemical analyses demonstrated high concentrations of PCBs, PAHs, chlorinated pesticides, and heavy metals in BRH sediment. Known genotoxic carcinogens, co-carcinogens, and tumor promoters were present as contaminants. The uptake of parent PAH and PCBs from BRH sediment observed in oysters also occurs in blue mussels (Mytilus edulis). Winter flounder fed BRH-contaminated blue mussels contained xenobiotic chemicals analyzed in mussels. The flounder developed renal and pancreatic neoplasms and hepatotoxic neoplastic precursor lesions, demonstrating trophic transfer of sediment-bound carcinogens up the food chain. Images FIGURE 2. FIGURE 3. FIGURE 4. FIGURE 5. FIGURE 6. FIGURE 7. FIGURE 8. FIGURE 9. FIGURE 10. PMID:2050083

  2. Carcinogenicity of Black Rock Harbor sediment to the eastern oyster and trophic transfer of Black Rock Harbor carcinogens from the blue mussel to the winter flounder

    SciTech Connect

    Gardner, G.R.; Yevich, P.P.; Malcolm, A.R. ); Harshbarger, J.C. )

    1991-01-01

    The eastern oyster (Crassostrea virginica) developed neoplastic disorders when experimentally exposed both in the laboratory and field to chemically contaminated sediment from Black Rock Harbor (BRH), Bridgeport, Connecticut. Neoplasia was observed in oysters after 30 or 60 days of continuous exposure in a laboratory flow-through system to a 20 mg/L suspension of BRH sediment plus postexposure periods of 3, 30, or 60 days. Composite tumor incidence was 13.6% for both exposures. Tumor occurrence was highest in the renal excretory epithelium, followed in order by gill, gonad, gastrointestinal, heart, and embryonic neural tissue. Regression of experimental neoplasia was not observed when the stimulus was discontinued. In field experiments, gill neoplasms developed in oysters, deployed in cages for 30 days at BRH and 36 days at a BRH dredge material disposal area in Central Long Island Sound, and kidney and gastrointestinal neoplasms developed in caged oysters deployed 40 days in Quincy Bay, Boston Harbor. Oysters exposed to BRH sediment in the laboratory and in the field accumulated high concentrations of polychlorinated biphenyls (PCBs), polyaromatic hydrocarbons (PAHs), and chlorinated pesticides. Chemical analyses demonstrated high concentrations of PCBs, PAHs, chlorinated pesticides, and heavy metals in BRH sediment. Known genotoxic carcinogens, cocarcinogens, and tumor promoters were present as contaminants. The uptake of parent PAH and PCBs from BRH sediment observed in oysters also occurs in blue mussels (Mytilus edulis). Winter flounder fed BRH-contaminated blue mussels contained xenobiotic chemicals analyzed in mussels. The flounder developed renal and pancreatic neoplasms and hepatotoxic neoplastic precursor lesions, demonstrating trophic transfer of sediment-bound carcinogens up the food chain.

  3. Alteration of Gene Expression Profile in Kidney of Spontaneously Hypertensive Rats Treated with Protein Hydrolysate of Blue Mussel (Mytilus edulis) by DNA Microarray Analysis.

    PubMed

    Feng, Junli; Dai, Zhiyuan; Zhang, Yanping; Meng, Lu; Ye, Jian; Ma, Xuting

    2015-01-01

    Marine organisms are rich sources of bioactive components, which are often reported to have antihypertensive effects. However, the underlying mechanisms have yet to be fully identified. The aim of this study was to investigate the antihypertensive effect of enzymatic hydrolysis of blue mussel protein (HBMP) in rats. Peptides with in vitro ACE inhibitory activity were purified from HBMP by ultrafiltration, gel filtration chromatography and reversed-phase high performance liquid chromatography. And the amino acid sequences of isolated peptides were estimated to be Val-Trp, Leu-Gly-Trp, and Met-Val-Trp-Thr. To study its in vivo action, spontaneously hypertensive rats (SHRs) were orally administration with high- or low-dose of HBMP for 28 days. Major components of the renin-angiotensin (RAS) system in serum of SHRs from different groups were analyzed, and gene expression profiling were performed in the kidney of SHRs, using the Whole Rat Genome Oligonucleotide Microarray. Results indicated although genes involved in RAS system were not significantly altered, those related to blood coagulation system, cytokine and growth factor, and fatty acids metabolism were remarkablely changed. Several genes which were seldom reported to be implicated in pathogenesis of hypertension also showed significant expression alterations after oral administration of HBMP. These data provided valuable information for our understanding of the molecular mechanisms that underlie the potential antihypertensive activities of HBMP, and will contribute towards increased value-added utilization of blue mussel protein. PMID:26517713

  4. The influence of ph and waterborne metals on egg fertilization of the blue mussel (Mytilus edulis), the oyster (Crassostrea gigas) and the sea urchin (Paracentrotus lividus).

    PubMed

    Riba, Inmaculada; Gabrielyan, Bardukh; Khosrovyan, Alla; Luque, Angel; Del Valls, T Angel

    2016-07-01

    This study evaluated the combined effect of pH and metals on the egg fertilization process of two estuarine species, the blue mussel (Mytilus edulis), the oyster (Crassostrea gigas) and a marine species, the sea urchin (Paracentrotus lividus). The success of egg fertilization was examined after exposure of gametes to sediment extracts of various degrees of contamination at pH 6.0, 6.5, 7.0, 7.5 and 8.0. At the pH levels from 6.5 to 8.0, the egg fertilization of the different species demonstrated different sensitivity to metal and/or acidic exposure. In all species, the results revealed that egg fertilization was almost completely inhibited at pH 6.0. The egg fertilization of the blue mussel M. edulis was the least sensitive to the exposure while that of the sea urchin P. lividus demonstrated a concentration-dependent response to the pH levels from 6.5 to 8.0. The results of this study revealed that acidity increased the concentration of several metal ions (Cr, Ni, Cu, Zn, Cd, and Pb) but reduced its availability to the organisms, probably related to the reactivity of the ions with most non-metals or to the competition among metals and other waterborne constituents. PMID:27068916

  5. Alteration of Gene Expression Profile in Kidney of Spontaneously Hypertensive Rats Treated with Protein Hydrolysate of Blue Mussel (Mytilus edulis) by DNA Microarray Analysis

    PubMed Central

    Feng, Junli; Dai, Zhiyuan; Zhang, Yanping; Meng, Lu; Ye, Jian; Ma, Xuting

    2015-01-01

    Marine organisms are rich sources of bioactive components, which are often reported to have antihypertensive effects. However, the underlying mechanisms have yet to be fully identified. The aim of this study was to investigate the antihypertensive effect of enzymatic hydrolysis of blue mussel protein (HBMP) in rats. Peptides with in vitro ACE inhibitory activity were purified from HBMP by ultrafiltration, gel filtration chromatography and reversed-phase high performance liquid chromatography. And the amino acid sequences of isolated peptides were estimated to be Val-Trp, Leu-Gly-Trp, and Met-Val-Trp-Thr. To study its in vivo action, spontaneously hypertensive rats (SHRs) were orally administration with high- or low-dose of HBMP for 28 days. Major components of the renin-angiotensin (RAS) system in serum of SHRs from different groups were analyzed, and gene expression profiling were performed in the kidney of SHRs, using the Whole Rat Genome Oligonucleotide Microarray. Results indicated although genes involved in RAS system were not significantly altered, those related to blood coagulation system, cytokine and growth factor, and fatty acids metabolism were remarkablely changed. Several genes which were seldom reported to be implicated in pathogenesis of hypertension also showed significant expression alterations after oral administration of HBMP. These data provided valuable information for our understanding of the molecular mechanisms that underlie the potential antihypertensive activities of HBMP, and will contribute towards increased value-added utilization of blue mussel protein. PMID:26517713

  6. Across-shelf distribution of blue mussel larvae in the northern Gulf of Maine: consequences for population connectivity and a species range boundary.

    PubMed

    Yund, Philip O; Tilburg, Charles E; McCartney, Michael A

    2015-12-01

    Studies of population connectivity have largely focused on along-shelf, as opposed to across-shelf, processes. We hypothesized that a discontinuity in across-shelf mixing caused by the divergence of the Eastern Maine Coastal Current (EMCC) from shore acts as an ecological barrier to the supply of mussel larvae to the coast. Existing data on the relative abundance of two congeneric blue mussels, Mytilus edulis and M. trossulus, were analysed to quantify the association of M. trossulus with the colder temperature signal of the EMCC and generate larval distribution predictions. We then sampled the across-shelf distribution of larvae along two transects during 2011. Larvae were identified using restriction digests of PCR amplicons from the mitochondrial 16S rDNA. Mytilus edulis larvae were consistently abundant on either the inshore and offshore transect ends, but not homogeneously distributed across the shelf, while M. trossulus larvae were less common throughout the study area. The divergence of the EMCC from shore appears to create a break in the connectivity of M. edulis populations by isolating those inshore of the EMCC from upstream larval sources. Across-shelf transport processes can thus produce connectivity patterns that would not be predicted solely on the basis of along-shelf processes. PMID:27018654

  7. Across-shelf distribution of blue mussel larvae in the northern Gulf of Maine: consequences for population connectivity and a species range boundary

    PubMed Central

    Yund, Philip O.; Tilburg, Charles E.; McCartney, Michael A.

    2015-01-01

    Studies of population connectivity have largely focused on along-shelf, as opposed to across-shelf, processes. We hypothesized that a discontinuity in across-shelf mixing caused by the divergence of the Eastern Maine Coastal Current (EMCC) from shore acts as an ecological barrier to the supply of mussel larvae to the coast. Existing data on the relative abundance of two congeneric blue mussels, Mytilus edulis and M. trossulus, were analysed to quantify the association of M. trossulus with the colder temperature signal of the EMCC and generate larval distribution predictions. We then sampled the across-shelf distribution of larvae along two transects during 2011. Larvae were identified using restriction digests of PCR amplicons from the mitochondrial 16S rDNA. Mytilus edulis larvae were consistently abundant on either the inshore and offshore transect ends, but not homogeneously distributed across the shelf, while M. trossulus larvae were less common throughout the study area. The divergence of the EMCC from shore appears to create a break in the connectivity of M. edulis populations by isolating those inshore of the EMCC from upstream larval sources. Across-shelf transport processes can thus produce connectivity patterns that would not be predicted solely on the basis of along-shelf processes. PMID:27018654

  8. The influence of structural features of marine humic substances on the accumulation rates of cadmium by a blue mussel Mytilus edulis

    SciTech Connect

    Pempkowiak, J.; Kozuch, J. ); Southon, T. )

    1994-01-01

    Laboratory experiments revealed that both concentration and origin of humic substances (HS) influence the accumulation rates of cadmium by the blue mussel Mytilus edulis. In the concentration of humic substances typical of seawater, the increase is about 60% and 100%, respectively, for aquatic and sedimentary humic substances. The phenomenon was attributed to the stimulation of cadmium uptake due to complexing properties of the substances toward cadmium. Complexing capacity of sedimentary humic substances was found to be 0.57 [mu]g/mg HS, that of aquatic substances 0.41 [mu]g/mg HS. Cross Polarization Magic Angle Spinning (CP/MAS) [sup 13]C NMR of the investigated humic substances revealed differences in the spectra at about 175, 100, 55 and 32 ppm. This was attributed to the varying content of oxygen containing functional groups involved in formation of complexes with metal ions. 8 refs., 4 figs., 3 tabs.

  9. An examination of the ingestion, bioaccumulation, and depuration of titanium dioxide nanoparticles by the blue mussel (Mytilus edulis) and the eastern oyster (Crassostrea virginica).

    PubMed

    Doyle, John J; Ward, J Evan; Mason, Robert

    2015-09-01

    The production rates of titanium dioxide (TiO2) nanoparticles for consumer products far exceed the pace at which research can determine the effects of these particles in the natural environment. Sedentary organisms such as suspension-feeding bivalves are particularly vulnerable to anthropogenic contaminants, such as nanoparticles, that enter coastal environments. The purpose of this work was to examine the ingestion, bioaccumulation, and depuration rates of TiO2 nanoparticles by two species of suspension-feeding bivalves, the blue mussel (Mytilus edulis) and the eastern oyster (Crassostrea virginica). Two representative TiO2 nanoparticles, UV-Titan M212 (Titan) and Aeroxide P25 (P25), were delivered to the animals either incorporated into marine snow or added directly to seawater at a concentration of 1.0 mg/L for exposure periods of 2 and 6 h. After feeding, the animals were transferred to filtered-seawater and allowed to depurate. Feces and tissues were collected at 0, 12, 24, 72, and 120 h, post-exposure, and analyzed for concentrations of titanium by inductively coupled plasma-mass spectrometry. Results indicated that the capture and ingestion (i.e., transfer to the gut) of TiO2 nanoparticles by both mussels and oysters was not dependent on the presence of marine snow, and weight-standardized clearance rates of bivalves exposed to TiO2 nanoparticles were not significantly different than those of unexposed control animals. Both species ingested about half of the nanoparticles to which they were exposed, and >90% of the nanoparticles were egested in feces within 12 h, post-exposure. The findings of this study demonstrate that mussels and oysters can readily ingest both Titan and P25 nanoparticles regardless of the form in which they are encountered, but depurate these materials over a short period of time. Importantly, bioaccumulation of Titan and P25 nanoparticles does not occur in mussels and oysters following exposures of up to 6 h. PMID:26263835

  10. Studying longterm effects of micro gravity on basic immune functions - The development of an application based on the measuring of phagocytosis activity of Blue Mussel hemocytes

    NASA Astrophysics Data System (ADS)

    Unruh, Eckehardt

    The immunsystem of astronauts exposed to microgravity is declining. Whether this effect is caused by microgravity or in combination with cosmic radiation is so far not clear. The immune system of vertebrates has several defence strategies but the basic immune response (Phagocytosis) is present as well in invertebrates. Phagocytotic cells are drawn by chemotaxis to the origin of an infection. By adhesion, ingestion and phagosome formation foreign particles, bacteria etc are transported inside of a cell were they are destroyed by native powerful biocides. Related to this biocide production is the formation of Reactive Oxygen Species (ROS). ROS can be measured by luminescence. The effects of microgravity will be simultaneously tested by exposure of phagocytotic hemocytes on orbit under microgravity, artificial gravity and, on ground under natural gravity. To address this purpose defined pools of Blue Mussel (Mytilus edulis) hemocytes will be launched frozen to the ISS. References for all batches will stay on ground. Shortly after arrival and then in three-month intervals batches of the same pool will be thawed and reconstituted. The phagocytosis related production of ROS will be stimulated with opsonized Zymosan. Luminescence will be measured and the data will be sent to ground. The experiment is scheduled for the Columbus Biolab early 2009. In preparation of this flight experiments the following procedures were investigated and the results will be presented: - a protocol for the cryoconservation and reconstituton of blue mussel hemocytes. - preliminary results of phagocytosis activity by reconstituted hemocytes after cryo-conservation and hemocytes without cryo-conservation treatment. The TRIPLELUX-B Experiment contributes to risk assessment concerning longterm immunotoxicity under space flight conditions. The immune system of invertebrates has not been studied so far in space. The choice of the phagocytes from invertebrates is justified by the claim to study the

  11. A comparison of scope for growth (SFG) and dynamic energy budget (DEB) models applied to the blue mussel ( Mytilus edulis)

    NASA Astrophysics Data System (ADS)

    Filgueira, Ramón; Rosland, Rune; Grant, Jon

    2011-11-01

    Growth of Mytilus edulis was simulated using individual based models following both Scope For Growth (SFG) and Dynamic Energy Budget (DEB) approaches. These models were parameterized using independent studies and calibrated for each dataset by adjusting the half-saturation coefficient of the food ingestion function term, XK, a common parameter in both approaches related to feeding behavior. Auto-calibration was carried out using an optimization tool, which provides an objective way of tuning the model. Both approaches yielded similar performance, suggesting that although the basis for constructing the models is different, both can successfully reproduce M. edulis growth. The good performance of both models in different environments achieved by adjusting a single parameter, XK, highlights the potential of these models for (1) producing prospective analysis of mussel growth and (2) investigating mussel feeding response in different ecosystems. Finally, we emphasize that the convergence of two different modeling approaches via calibration of XK, indicates the importance of the feeding behavior and local trophic conditions for bivalve growth performance. Consequently, further investigations should be conducted to explore the relationship of XK to environmental variables and/or to the sophistication of the functional response to food availability with the final objective of creating a general model that can be applied to different ecosystems without the need for calibration.

  12. Validation of the flooding dose technique to determine fractional rates of protein synthesis in a model bivalve species, the blue mussel (Mytilus edulis L.).

    PubMed

    McCarthy, Ian D; Nicholls, Ruth; Malham, Shelagh K; Whiteley, Nia M

    2016-01-01

    For the first time, use of the flooding dose technique using (3)H-Phenylalanine is validated for measuring whole-animal and tissue-specific rates of protein synthesis in the blue mussel Mytilus edulis (61mm shell length; 4.0g fresh body mass). Following injection, the phenylalanine-specific radioactivities in the gill, mantle and whole-animal free pools were elevated within one hour and remained elevated and stable for up to 6h following injection of (3)H-phenylalanine into the posterior adductor muscle. Incorporation of (3)H-phenylalanine into body protein was linear over time following injection and the non-significant intercepts for the regressions suggested incorporation into body protein occurred rapidly after injection. These results validate the technique for measuring rates of protein synthesis in mussels. There were no differences in the calculated rates following 1-6h incubation in gill, mantle or whole-animal and fractional rates of protein synthesis from the combined time course data were 9.5±0.8%d(-1) for the gill, 2.5±0.3%d(-1) for the mantle and 2.6±0.3%d(-1) for the whole-animal, respectively (mean values±SEM). The whole-animal absolute rate of protein synthesis was calculated as 18.9±0.6mg protein day(-1). The use of this technique in measuring one of the major components of maintenance metabolism and growth will provide a valuable and convenient tool in furthering our understanding of the protein metabolism and energetics of this keystone marine invertebrate and its ability to adjust and respond to fluctuations, such as that expected as a result of climate change. PMID:26497279

  13. Seasonal variation in biomarkers in blue mussel (Mytilus edulis), Icelandic scallop (Chlamys islandica) and Atlantic cod (Gadus morhua): implications for environmental monitoring in the Barents Sea.

    PubMed

    Nahrgang, J; Brooks, S J; Evenset, A; Camus, L; Jonsson, M; Smith, T J; Lukina, J; Frantzen, M; Giarratano, E; Renaud, P E

    2013-02-01

    In the Barents Sea, the limited data on biological relevant indicators and their responses to various anthropogenic stressors have hindered the development of a consistent scientific basis for selecting indicator species and developing practical procedures for environmental monitoring. Accordingly, the main aim of the present study was to develop a common set of baseline values for contaminants and biomarkers in three species, and to identify their strengths and limitations in monitoring of the Barents Sea. Blue mussel (Mytilus edulis), Icelandic scallop (Chlamys islandica) and Atlantic cod (Gadus morhua) were sampled from a north Norwegian fjord in March, June, September and December 2010. Digestive glands from the bivalve species and liver from Atlantic cod were analysed for biomarkers of oxidative stress (catalase [CAT], glutathione peroxidase [GPX], glutathione-S-transferase activities [GST], lipid peroxidation as thiobarbituric reactive substances [TBARS] and total oxyradical scavenging capacity [TOSC]), biotransformation (ethoxyresorufine-O-deethylase activity [EROD]) and general stress (lysosomal membrane stability [LMS]). Concentrations of polycyclic aromatic hydrocarbons (PAHs) and metals in the bivalves and PAH metabolites in fish bile were quantified. Finally, energy reserves (total lipids, proteins and carbohydrates) and electron transport system (ETS) activity in the digestive gland of the bivalves and liver of Atlantic cod provided background information for reproductive cycle and general physiological status of the organisms. Blue mussel and Icelandic scallop showed very similar trends in biological cycle, biomarker expression and seasonality. Biomarker baselines in Atlantic cod showed weaker seasonal variability. However, important biological events may have been undetected due to the large time intervals between sampling occasions. Physiological biomarkers such as energy reserves and ETS activity were recommended as complementary parameters to the

  14. Genotoxic and immunotoxic potential effects of selected psychotropic drugs and antibiotics on blue mussel (Mytilus edulis) hemocytes.

    PubMed

    Lacaze, Emilie; Pédelucq, Julie; Fortier, Marlène; Brousseau, Pauline; Auffret, Michel; Budzinski, Hélène; Fournier, Michel

    2015-07-01

    The potential toxicity of pharmaceuticals towards aquatic invertebrates is still poorly understood and sometimes controversial. This study aims to document the in vitro genotoxicity and immunotoxicity of psychotropic drugs and antibiotics on Mytilus edulis. Mussel hemocytes were exposed to fluoxetine, paroxetine, venlafaxine, carbamazepine, sulfamethoxazole, trimethoprim and erythromycin, at concentrations ranging from μg/L to mg/L. Paroxetine at 1.5 μg/L led to DNA damage while the same concentration of venlafaxine caused immunomodulation. Fluoxetine exposure resulted in genotoxicity, immunotoxicity and cytotoxicity. In the case of antibiotics, trimethoprim was genotoxic at 200 μg/L and immunotoxic at 20 mg/L whereas erythromycin elicited same detrimental effects at higher concentrations. DNA metabolism seems to be a highly sensitive target for psychotropic drugs and antibiotics. Furthermore, these compounds affect the immune system of bivalves, with varying intensity. This attests the relevance of these endpoints to assess the toxic mode of action of pharmaceuticals in the aquatic environment. PMID:25829077

  15. Active and passive biomonitoring suggest metabolic adaptation in blue mussels (Mytilus spp.) chronically exposed to a moderate contamination in Brest harbor (France).

    PubMed

    Lacroix, Camille; Richard, Gaëlle; Seguineau, Catherine; Guyomarch, Julien; Moraga, Dario; Auffret, Michel

    2015-05-01

    Brest harbor (Bay of Brest, Brittany, France) has a severe past of anthropogenic chemical contamination, but inputs tended to decrease, indicating a reassessment of its ecotoxicological status should be carried out. Here, native and caged mussels (Mytilus spp.) were used in combination to evaluate biological effects of chronic chemical contamination in Brest harbor. Polycyclic aromatic hydrocarbon (PAH) contamination was measured in mussel tissues as a proxy of harbor and urban pollution. Biochemical biomarkers of xenobiotic biotransformation, antioxidant defenses, generation of reducing equivalents, energy metabolism and oxidative damage were studied in both gills and digestive glands of native and caged mussels. In particular, activities of glutathione-S-transferase (GST), superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GPx), glutathione reductase (GR), NADP-dependent isocitrate dehydrogenase (IDP), pyruvate kinase (PK) and phosphoenolpyruvate carboxykinase (PEPCK) were measured and lipid peroxidation was assessed by malondialdehyde (MDA) quantification. In addition, a condition index was calculated to assess the overall health of the mussels. Moderate PAH contamination was detected in digestive glands of both native and caged individuals from the exposed site. Modulations of biomarkers were detected in digestive glands of native harbor mussels indicating the presence of a chemical pressure. In particular, results suggested increased biotransformation (GST), antioxidant defenses (CAT), NADPH generation (IDP) and gluconeogenesis (PEPCK), which could represent a coordinated response against chemically-induced cellular stress. Lipid peroxidation assessment and condition index indicated an absence of acute stress in the same mussels suggesting metabolic changes could, at least partially, offset the negative effects of contamination. In caged mussels, only GR was found modulated compared to non-exposed mussels but significant differences in

  16. COMPARISON OF SEVERAL PHYSIOLOGICAL MONITORING TECHNIQUES AS APPLIED TO THE BLUE MUSSEL, 'MYTILUS EDULIS' ALONG A GRADIENT OF POLLUTANT STRESS IN NARRAGANSETT BAY, RHODE ISLAND

    EPA Science Inventory

    Sublethal pollutant stress in mussels was clearly detected in a field-monitoring situation and provides an evaluation of several criteria of physiological response. This study presents the necessary coupling of tissue residue analyses to biological effects, a blending of chemistr...

  17. Environmental factors influencing human viral pathogens and their potential indicator organisms in the blue mussel, Mytilus edulis: the first Scandinavian report.

    PubMed

    Hernroth, Bodil E; Conden-Hansson, Ann-Christine; Rehnstam-Holm, Ann-Sofi; Girones, Rosina; Allard, Annika K

    2002-09-01

    This study was carried out in order to investigate human enteric virus contaminants in mussels from three sites on the west coast of Sweden, representing a gradient of anthropogenic influence. Mussels were sampled monthly during the period from February 2000 to July 2001 and analyzed for adeno-, entero-, Norwalk-like, and hepatitis A viruses as well as the potential viral indicator organisms somatic coliphages, F-specific RNA bacteriophages, bacteriophages infecting Bacteroides fragilis, and Escherichia coli. The influence of environmental factors such as water temperature, salinity, and land runoff on the occurrence of these microbes was also included in this study. Enteric viruses were found in 50 to 60% of the mussel samples, and there were no pronounced differences between the samples from the three sites. E. coli counts exceeded the limit for category A for shellfish sanitary safety in 40% of the samples from the sites situated in fjords. However, at the site in the outer archipelago, this limit was exceeded only once, in March 2001, when extremely high levels of atypical indole-negative strains of E. coli were registered at all three sites. The environmental factors influenced the occurrence of viruses and phages differently, and therefore, it was hard to find a coexistence between them. This study shows that, for risk assessment, separate modeling should be done for every specific area, with special emphasis on environmental factors such as temperature and land runoff. The present standard for human fecal contamination, E. coli, seems to be an acceptable indicator of only local sanitary contamination; it is not a reliable indicator of viral contaminants in mussels. To protect consumers and get verification of "clean" mussels, it seems necessary to analyze for viruses as well. The use of a molecular index of the human contamination of Swedish shellfish underscores the need for reference laboratories with high-technology facilities. PMID:12200309

  18. Environmental Factors Influencing Human Viral Pathogens and Their Potential Indicator Organisms in the Blue Mussel, Mytilus edulis: the First Scandinavian Report

    PubMed Central

    Hernroth, Bodil E.; Conden-Hansson, Ann-Christine; Rehnstam-Holm, Ann-Sofi; Girones, Rosina; Allard, Annika K.

    2002-01-01

    This study was carried out in order to investigate human enteric virus contaminants in mussels from three sites on the west coast of Sweden, representing a gradient of anthropogenic influence. Mussels were sampled monthly during the period from February 2000 to July 2001 and analyzed for adeno-, entero-, Norwalk-like, and hepatitis A viruses as well as the potential viral indicator organisms somatic coliphages, F-specific RNA bacteriophages, bacteriophages infecting Bacteroides fragilis, and Escherichia coli. The influence of environmental factors such as water temperature, salinity, and land runoff on the occurrence of these microbes was also included in this study. Enteric viruses were found in 50 to 60% of the mussel samples, and there were no pronounced differences between the samples from the three sites. E. coli counts exceeded the limit for category A for shellfish sanitary safety in 40% of the samples from the sites situated in fjords. However, at the site in the outer archipelago, this limit was exceeded only once, in March 2001, when extremely high levels of atypical indole-negative strains of E. coli were registered at all three sites. The environmental factors influenced the occurrence of viruses and phages differently, and therefore, it was hard to find a coexistence between them. This study shows that, for risk assessment, separate modeling should be done for every specific area, with special emphasis on environmental factors such as temperature and land runoff. The present standard for human fecal contamination, E. coli, seems to be an acceptable indicator of only local sanitary contamination; it is not a reliable indicator of viral contaminants in mussels. To protect consumers and get verification of “clean” mussels, it seems necessary to analyze for viruses as well. The use of a molecular index of the human contamination of Swedish shellfish underscores the need for reference laboratories with high-technology facilities. PMID:12200309

  19. Flow cytometric measurement of the clearance rate in the blue mussel Mytilus edulis and the development of a new individual exposure system for aquatic immunotoxicological studies.

    PubMed

    Duchemin, Matthieu B; Wessel, Nathalie; Fournier, Michel; Auffret, Michel

    2008-05-01

    Animals in poor health condition are not relevant biological models. The current study focused on the use of the clearance rate of Mytilus edulis to assess the gross physiological condition of individuals maintained in stressful experimental conditions. This approach was developed in a new, highly controlled experimental exposure device designed to investigate individual responses in aquatic ecotoxicological studies. Both clearance rate values and immune parameters analysis indicated that the health condition of mussels kept in 50ml tubes for 24h or 48h was not altered compared to controls, while most parameters were depressed after 72h. Moreover, this study confirms the relevance of flow cytometric for the measurement of clearance rate compared to techniques utilizing microscopy. Current results prompted us to perform further 24h chemical exposure using this "in tubo" device. PMID:17905494

  20. 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.

  1. Improved detection of β-N-methylamino-L-alanine using N-hydroxysuccinimide ester of N-butylnicotinic acid for the localization of BMAA in blue mussels (Mytilus edulis).

    PubMed

    Andrýs, Rudolf; Zurita, Javier; Zguna, Nadezda; Verschueren, Klaas; De Borggraeve, Wim M; Ilag, Leopold L

    2015-05-01

    β-N-Methylamino-L-alanine (BMAA) is an important non-protein amino acid linked to neurodegenerative diseases, specifically amyotrophic lateral sclerosis (ALS). Because it can be transferred and bioaccumulated higher up the food chain, it poses significant public health concerns; thus, improved detection methods are of prime importance for the identification and management of these toxins. Here, we report the successful use of N-hydroxysuccinimide ester of N-butylnicotinic acid (C4-NA-NHS) for the efficient separation of BMAA from its isomers and higher sensitivity in detecting BMAA compared to the current method of choice using 6-aminoquinolyl-N-hydroxysuccinimidyl carbamate (AQC) derivatization. Implementation of this efficient method allowed localization of BMAA in the non-visceral tissues of blue mussels, suggesting that more efficient depuration may be required to remove this toxin prior to consumption. This is a crucial method in establishing the absence or presence of the neurotoxic amino acid BMAA in food, environmental or biomedical samples. PMID:25821115

  2. 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

    1. Exotic zebra mussels, Dreissena polymorpha, occur in southern U.S. waterways in high densities, but little is known about the interaction between native fish predators and zebra mussels. Previous studies have suggested that exotic zebra mussels are low profitability prey items and native vertebrate predators are unlikely to reduce zebra mussel densities. We tested these hypotheses by observing prey use of fishes, determining energy content of primary prey species of fishes, and conducting predator exclusion experiments in Lake Dardanelle, Arkansas. 2. Zebra mussels were the primary prey eaten by 52.9% of blue catfish, Ictalurus furcatus; 48.2% of freshwater drum, Aplodinotus grunniens; and 100% of adult redear sunfish, Lepomis microlophus. Blue catfish showed distinct seasonal prey shifts, feeding on zebra mussels in summer and shad, Dorosoma spp., during winter. Energy content (joules g-1) of blue catfish prey (threadfin shad, Dorosoma petenense; gizzard shad, D. cepedianum; zebra mussels; and asiatic clams, Corbicula fluminea) showed a significant species by season interaction, but shad were always significantly greater in energy content than bivalves examined as either ash-free dry mass or whole organism dry mass. Fish predators significantly reduced densities of large zebra mussels (>5 mm length) colonising clay tiles in the summers of 1997 and 1998, but predation effects on small zebra mussels (???5 mm length) were less clear. 3. Freshwater drum and redear sunfish process bivalve prey by crushing shells and obtain low amounts of higher-energy food (only the flesh), whereas blue catfish lack a shell-crushing apparatus and ingest large amounts of low-energy food per unit time (bivalves with their shells). Blue catfish appeared to select the abundant zebra mussel over the more energetically rich shad during summer, then shifted to shad during winter when shad experienced temperature-dependent stress and mortality. Native fish predators can suppress adult zebra

  3. The Mussels' Message.

    ERIC Educational Resources Information Center

    Stolzenburg, William

    1992-01-01

    Presents research findings about mussels, an indicator species for the health of U.S. rivers and streams. Provides mussel descriptions, a history of the decline of mussel populations and cooperative efforts to repair damaged ecosystems cited as the root of the problem. (MCO)

  4. Detection of mutagenicity in mussels and their ambient water

    SciTech Connect

    Kira, Shohei; Hayatsu, Hikoya; Ogata, Masana )

    1989-10-01

    Mussels provide an excellent system for monitoring marine pollutants: the system is often called mussel watch. Investigators have reported the susceptibility of this organism to petroleum hydrocarbons and polynuclear aromatic hydrocarbons. The authors showed the applicability of this organism to monitor oil pollutions by detecting organosulfur compounds in field samples. In the present study, they undertook the mutagen screening of mussel bodies and ambient water, and investigated the correlation between the mussel- and water-mutagenicities. Mutagenic compounds being detected here are those adsorbable to blue cotton or blue rayon and extractable with a methanol-ammonia solution, and the Ames assay was used for the detection of mutagenicity, with Salmonella typhimurium TA98 as the ester strain and with S9-mix for metabolic activation.

  5. Polycyclic aromatic hydrocarbons in mussel and fish from the Finnish Archipelago Sea

    SciTech Connect

    Not Available

    1986-09-01

    Marine organisms are known to adsorb and accumulate PAH's from water. Mussels due to their widespread distribution in coastal waters have been studied in many laboratory and field experiments for their responses to PAH exposures. The occurrence of PAH's has been studied also in fish. This report presents preliminary data for the PAH content in blue mussel and fish from the Finnish Archipelago Sea. Mussel and fish samples were collected from the Finnish Archipelago Sea during 1978-1979.

  6. 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.

  7. Zebra mussel monitoring

    SciTech Connect

    Hennagir, T.

    1994-01-01

    In less than a decade, zebra mussels have become the latest environmental scourge to plague the North American power industry. Infestations in the Great Lakes region have already reached natural disaster proportions. The invasion shows little sign of subsiding; Michigan's inland waters are the next most likely threatened area. In the southern United States, the mussles' migration has extended about 50 miles deeper than experts had originally predicted. By the year 2000, zebra mussel monitoring and control efforts will cost business and industry $5 billion, according to the federal Aquatic Nuisance Prevention and Control Act of 1990. Estimates of more than $1 million to control mussel fouling are projected for the Great Lakes area alone. While small independent hydropower stations are not as susceptible to zebra mussles as coal or nuclear facilities, there is cause for concern. Infestations can quickly foul hydropower plant components, hampering equipment operation and reducing facility efficiency. In extreme cases, leaving the mussels unchecked can result in stoplog gate flow blockage or false water level gauge readings. Advance prevention is often an effective first-line of defense against this troublesome, rapidly spreading and extremely prolific mollusk. Mussel monitoring efforts should begin a year in advance of when zebra mussels are expected to appear in a given location. Hydropower facility components that come into contact or rely exclusively on raw water are at greatest risk, as are other external components such as embayment walls, screens, trashracks and fish ladders.

  8. Zebra mussel life history

    SciTech Connect

    Ackerman, J.D.

    1995-06-01

    The success of introduced zebra mussels (Dreissena polymorpha (Pallas) and Dreissena bugensis Andrusova) can be related in large parttot a life history that is unlike that of the indigenous freshwater fauna and yet is conserved with marine bivalves. Following external fertilization and embryological development, there is a brief trochophore stage. With the development of a velum and the secretion of a D-shaped larval shell, the larva becomes a D-shaped veliger, which is the first recognizable planktonic larva. Later, the secretion of a second larval shell leads to the last obligate free-swimming veliger stage known as the veliconcha. The last larval stage known as the pediveliger, however, can both swim using its velum or crawl using its fully-functional foot. Pediveligers actively select substrates on which they {open_quotes}settle{close_quotes} by secreting byssal threads and undergo metamorphosis to become plantigrade mussels. The secretion of the adult shell and concomitant changes in growth axis leads to the heteromyariant or mussel-like shape, which is convergent with marine mussels. Like a number of other bivalves, zebra mussels produce byssal threads as adults, but these attachments may be broken enabling their translocation to new areas. The recognition and examination of these life history traits will lead to a better understanding of zebra mussel biology.

  9. Dreissenid mussel research priorities workshop

    USGS Publications Warehouse

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

    2016-01-01

    On November 4-5, 2015, a Dreissenid Mussel Research Priorities Workshop funded by the Great Northern Landscape Conservation Cooperative occurred at Portland State University. The purpose of the workshop was to update research priorities in the 2010 Quagga-Zebra Mussel Action Plan in light of the westward expansion of mussels in the United States and Canada.

  10. Zebra mussel mitigation; overview

    SciTech Connect

    Claudi, R.

    1995-06-01

    Zebra mussels cause a number of problems to industrial raw water users as well as having serious impact on civil structures exposed to mussel infested waters. The largest volume of water (up to 90% of the total) drawn into most industrial and power generating plants, is for cooling and heat transfer. The rest of the volume is used for other plant processes, such as make-up in steam systems, and service systems used for cleaning, air conditions, fire protection and human consumption. All raw water systems are vulnerable to zebra mussel infestation to greater or lesser degree. To-date, many different chemical and non-chemical techniques for zebra mussel control have been investigated. However, the treatment of choice for most facilities is based on chemical control. This has been the common practice in Europe and so far it has been the case in North America. This is likely to change as the environmental constraints on release of chemicals into natural water bodies continue to increase. This paper deals with the different steps raw water users should take when deciding on a mitigation strategy, the mitigation measures available to-date and those that have been proposed for the control of zebra mussels in industrial systems.

  11. Mussel-Inspired Materials: Self-Healing through Coordination Chemistry.

    PubMed

    Krogsgaard, Marie; Nue, Vicki; Birkedal, Henrik

    2016-01-18

    Improved understanding of the underwater attachment strategy of the blue mussels and other marine organisms has inspired researchers to find new routes to advanced materials. Mussels use polyphenols, such as the catechol-containing amino acid 3,4-dihydroxyphenylalanine (DOPA), to attach to surfaces. Catechols and their analogues can undergo both oxidative covalent cross-linking under alkaline conditions and take part in coordination chemistry. The former has resulted in the widespread use of polydopamine and related materials. The latter is emerging as a tool to make self-healing materials due to the reversible nature of coordination bonds. We review how mussel-inspired materials have been made with a focus on the less developed use of metal coordination and illustrate how this chemistry can be widely to make self-healing materials. PMID:26558881

  12. Of Mussels and Men.

    PubMed

    Evans, Robert G

    2016-08-01

    Some species are more equal than others. Robert T. Paine (American ecologist, 1933-2016) discovered that if you remove starfish - what he called a "keystone species" - from a tide pool, the complex ecosystem collapses. Without the predator starfish, mussels choke out other animals and plants. This phenomenon is general. Sea otters eat the sea urchins that eat the kelp that provides food and habitat for other species. On the vast Serengeti plains, wildebeest "mow" the grass, protecting habitat for many other species. Understanding the "rules" that govern the numbers and diversity of species in an ecosystem is essential to efficient and sustainable management. But those same rules apply to us. Free of predation, humans are swarming over the planet, choking out other species. We are the planetary mussels. What next? A "mussel-bound" world, or perhaps renewed microbial predation? PMID:27585022

  13. Chemical and ancillary data associated with bed sediment, young of year Bluefish (Pomatomus saltatrix) tissue, and mussel (Mytilus edulis and Geukensia demissa) tissue collected after Hurricane Sandy in bays and estuaries of New Jersey and New York, 2013–14

    USGS Publications Warehouse

    Smalling, Kelly L.; Deshpande, Ashok D.; Blazer, Vicki; Galbraith, Heather S.; Dockum, Bruce W.; Romanok, Kristin M.; Colella, Kaitlyn; Deetz, Anna C.; Fisher, Irene J.; Imbrigiotta, Thomas E.; Sharack, Beth; Summer, Lisa; Timmons, DeMond; Trainor, John J.; Wieczorek, Daniel; Samson, Jennifer; Reilly, Timothy J.; Focazio, Michael J.

    2015-01-01

    Twenty three PCB congeners, 9 PBDE congeners, and 20 OCPs were detected in composite mussel samples collected throughout the study area. The co-eluting PCB congeners 153 and 132, PBDE 47, 99, and 100, and p,p’-DDE were detected in samples from each site. The highest median concentrations of PCBs and PBDEs were present in mussels from Raritan Bay, N.Y., whereas the highest median concentrations of OCPs were present in mussels from Fire Island Inlet, N.Y., and Shark River, N.J. Mytilus edulis (blue mussels) and Geukensia demissa (ribbed mussels) were thin-sectioned and aged. The blue mussels collected ranged in age from 4 to 13 years, and the ribbed mussels ranged in age from 3 to 12 years.

  14. Measuring bioavailable metals using diffusive gradients in thin films (DGT) and transplanted seaweed (Fucus vesiculosus), blue mussels (Mytilus edulis) and sea snails (Littorina saxatilis) suspended from monitoring buoys near a former lead-zinc mine in West Greenland.

    PubMed

    Søndergaard, Jens; Bach, Lis; Gustavson, Kim

    2014-01-15

    Measuring loads of bioavailable metals is important for environmental assessment near mines and other industrial sources. In this study, a setup of monitoring buoys was tested to assess loads of bioavailable metals near a former Pb-Zn mine in West Greenland using transplanted seaweed, mussels and sea snails. In addition, passive DGT samplers were installed. After a 9-day deployment period, concentrations of especially Pb, Zn and Fe in the species were all markedly elevated at the monitoring sites closest to the mine. Lead concentrations in all three species and the DGT-Pb results showed a significant linear correlation. Zinc and Fe concentrations were less correlated indicating that the mechanisms for Zn and Fe accumulation in the three species are more complex. The results show that there is still a significant load of metals from the mine and that such buoys can be an adequate method to assess present loads of bioavailable metals. PMID:24253021

  15. Norovirus recognizes histo-blood group antigens on the gastrointestinal cells of clams, mussels and oysters: a possible mechanism of bio-accumulation

    Technology Transfer Automated Retrieval System (TEKTRAN)

    In this study, a set of HBGA-specific monoclonal antibodies (MAbs) was used to detect the expression of HBGA in three oyster species consumed commonly (pacific, virginica, and kumamato), and manila clams, and blue mussels. rNVLPs were applied to plate coated with oyster, mussel or clam GI homogena...

  16. Somatic growth of mussels Mytilus edulis in field studies compared to predictions using BEG, DEB, and SFG models

    NASA Astrophysics Data System (ADS)

    Larsen, Poul S.; Filgueira, Ramón; Riisgård, Hans Ulrik

    2014-04-01

    Prediction of somatic growth of blue mussels, Mytilus edulis, based on the data from 2 field-growth studies of mussels in suspended net-bags in Danish waters was made by 3 models: the bioenergetic growth (BEG), the dynamic energy budget (DEB), and the scope for growth (SFG). Here, the standard BEG model has been expanded to include the temperature dependence of filtration rate and respiration and an ad hoc modification to ensure a smooth transition to zero ingestion as chlorophyll a (chl a) concentration approaches zero, both guided by published data. The first 21-day field study was conducted at nearly constant environmental conditions with a mean chl a concentration of C = 2.7 μg L- 1, and the observed monotonous growth in the dry weight of soft parts was best predicted by DEB while BEG and SFG models produced lower growth. The second 165-day field study was affected by large variations in chl a and temperature, and the observed growth varied accordingly, but nevertheless, DEB and SFG predicted monotonous growth in good agreement with the mean pattern while BEG mimicked the field data in response to observed changes in chl a concentration and temperature. The general features of the models were that DEB produced the best average predictions, SFG mostly underestimated growth, whereas only BEG was sensitive to variations in chl a concentration and temperature. DEB and SFG models rely on the calibration of the half-saturation coefficient to optimize the food ingestion function term to that of observed growth, and BEG is independent of observed actual growth as its predictions solely rely on the time history of the local chl a concentration and temperature.

  17. Detroit Edison conquers zebra mussels

    SciTech Connect

    Harwood, D.B.; Buda, D.J. )

    1993-11-01

    A potentially troublesome zebra mussel infestation at Detroit Edison's Harbor Beach Power Plant was nipped in time. Reducing the oxygen content of water inside the plant's water systems and using steam to thermally treat a colony of mussels that was established in the plant's screenhouse prevented the problem. So successful was the temperature treatment that it will be used regularly as part of the plant's annual mussel removal program.

  18. Elemental Fingerprinting of Mussel Shells to Predict Population Sources and Redistribution Potential in the Gulf of Maine

    PubMed Central

    Sorte, Cascade J. B.; Etter, Ron J.; Spackman, Robert; Boyle, Elizabeth E.; Hannigan, Robyn E.

    2013-01-01

    As the climate warms, species that cannot tolerate changing conditions will only persist if they undergo range shifts. Redistribution ability may be particularly variable for benthic marine species that disperse as pelagic larvae in ocean currents. The blue mussel, Mytilus edulis, has recently experienced a warming-related range contraction in the southeastern USA and may face limitations to northward range shifts within the Gulf of Maine where dominant coastal currents flow southward. Thus, blue mussels might be especially vulnerable to warming, and understanding dispersal patterns is crucial given the species' relatively long planktonic larval period (>1 month). To determine whether trace elemental “fingerprints” incorporated in mussel shells could be used to identify population sources (i.e. collection locations), we assessed the geographic variation in shell chemistry of blue mussels collected from seven populations between Cape Cod, Massachusetts and northern Maine. Across this ∼500 km of coastline, we were able to successfully predict population sources for over two-thirds of juvenile individuals, with almost 80% of juveniles classified within one site of their collection location and 97% correctly classified to region. These results indicate that significant differences in elemental signatures of mussel shells exist between open-coast sites separated by ∼50 km throughout the Gulf of Maine. Our findings suggest that elemental “fingerprinting” is a promising approach for predicting redistribution potential of the blue mussel, an ecologically and economically important species in the region. PMID:24244724

  19. Putative identification of expressed genes associated with attachment of the zebra mussel (Dreissena polymorpha).

    PubMed

    Xu, Wei; Faisal, Mohamed

    2008-01-01

    Because of its aggressive growth and firm attachment to substrata, the zebra mussel (Dreissena polymorpha) has caused severe economic and ecological problems since its invasion into North America. The nature and details of attachment of this nuisance mollusc remains largely unexplored. Byssus, a special glandular apparatus located at the root of the foot of the mussel produces threads and plates through which firm attachment of the mollusc to underwater objects takes place. In an attempt to better understand the adhesion mechanism of the zebra mussel, the suppression subtractive hybridization (SSH) assay was employed to produce a cDNA library with genes unique to the foot of the mussel. Analysis of the SSH cDNA library revealed the presence of 750 new expressed sequence tags (ESTs) including 304 contigs and 446 singlets. Using BLAST search, 365 zebra mussel ESTs showed homology to other gene sequences with putative functions. The putative functions of the homologues included proteins involved in byssal thread formation in zebra and blue mussels, exocrine gland secretion, host defence, and house keeping. The generated data provide, for the first time, some useful insights into the foot structure of the zebra mussel and its underwater adhesion. PMID:18330781

  20. Results of an in-situ mussel bioassay in the Puget Sound

    SciTech Connect

    Houkal, D.; Rummel, B.; Shephard, B.

    1995-12-31

    As part of an ecological evaluation in the Puget Sound, Washington, an in situ bioassay using the blue mussel (Mytilus galloprovincialis) was conducted to determine the effect of sediment-borne chemicals on bioaccumulation and growth of shellfish. The assay included four sample stations from a contaminated embayment (Sinclair Inlet) and one station from a reference site (Holmes Harbor). At each station, 300 mussels were deployed 1 meter above the sediment surface and maintained for a period of 3 months. The length and total weight of each mussel was measured at the beginning of the exposure period and the length, total weight, tissue weight, and shell weight of each mussel was measured at the end of the exposure period. Composite tissue samples from 100 mussels were collected at the beginning and end of the exposure period and analyzed for semivolatile organic chemicals, chlorinated pesticides, polychlorinated biphenyls, inorganic chemicals, organotin, and lipids. Water quality measurements (including temperature, salinity, dissolved oxygen, and chlorophyll a) were made at each station every two weeks during the assay to characterize environmental factors influencing mussel bioaccumulation and growth. Weight growth was similar among stations in Sinclair Inlet, but was significantly greater in all Sinclair Inlet stations compared to the Holmes Harbor reference station. Length growth was statistically indistinguishable among stations in Sinclair Inlet. Only one Sinclair Inlet station had a significantly greater length growth compared to the Holmes Harbor reference station. The influence of water quality on mussel growth is presented. The correlation between sediment chemistry and bioaccumulation is discussed.

  1. Comparison of metal accumulation in mussels at different local and global scales.

    PubMed

    Blackmore, Graham; Wang, Wen-Xiong

    2003-02-01

    Cadmium and zinc uptake from the dissolved phase, assimilation efficiency (AE) from the dietary phase, and body burden as well as clearance rate were measured in green mussels, Perna viridis, and blue mussels Mytilus edulis, M. galloprovincialis and Mytilus trossulus. Perna viridis was collected from four sites differentially enriched with trace metals in Hong Kong and blue mussels were collected from different climatic zones, i.e., subarctic and temperate, to allow comparisons with the more tropical green mussels. Despite similar shell length, the dry weight of mussels varied significantly between sites and species and this had a large effect on Cd and Zn accumulation, clearance rate, and metal body burden. All data were, therefore, weight adjusted to allow comparison without this confounding factor. Trace-metal body concentrations were significantly different between sites, and P. viridis collected from Tsing Yi, Hong Kong, had the highest levels of all measured metals when compared with other Hong Kong sites. There was, however, no relationship between the degree of metal enrichment and the Cd and Zn uptake (both from dissolved and particulate sources) and clearance rates. Furthermore, Cd and Zn uptake (dissolved and particulate) and clearance rate varied little between species or climatic zones of collection. Thus, over the range of body trace-metal concentrations measured and between mussel species over large geographical distances and climatic zones, the uptake rates, AEs, and clearance rates are similar when measured under the same laboratory conditions after body-size correction. When other factors such as salinity are also corrected, biomonitoring data from different areas and even utilizing different mussel species may be directly comparable. This study therefore provides important evidence in support of Mussel Watch Programs. PMID:12558172

  2. Effect of salinity on filtration rates of mussels Mytilus edulis with special emphasis on dwarfed mussels from the low-saline Central Baltic Sea

    NASA Astrophysics Data System (ADS)

    Riisgård, H. U.; Lüskow, F.; Pleissner, D.; Lundgreen, K.; López, M. Á. P.

    2013-09-01

    The effect of salinity on the filtration rate of blue mussels, Mytilus edulis, from the brackish Great Belt (Denmark) and the low-saline Central Baltic Sea, respectively, was studied. First, we measured the effect of long-term (weeks) constant ambient salinities between 5 and 30 psu on the filtration rate of M. edulis collected in the Great Belt where the mean salinity is 17 psu. At salinities between 10 and 30 psu, the filtration rates did not vary much, but at 5 psu the filtration rates were significantly lower. Next, we studied dwarfed M. edulis (<25 mm shell length) from Central Baltic Sea (Askö, Sweden) where the mean salinity is 6.5 psu. The maximum filtration rate ( F, ml min-1 ind.-1) as a function of shell length ( L, mm) and dry weight of soft parts ( W, mg) were found to be: F = 0.003 L 2.71 and F = 0.478 W 0.92, respectively, and these results indicate that the filtration rates of dwarfed Baltic Sea mussels are comparable to filtration rates of Great Belt mussels of similar size exposed to salinities >10 psu. When Baltic Sea mussels acclimatized to 20 psu in the laboratory were exposed to 6.5 psu this caused a drastic reduction in the filtration rate, but after about 2 days the previous high filtration rate was regained at 6.5 psu, and further, a similar pattern was observed when the 6.5 psu exposed mussels were finally re-exposed to 20 psu. The observed lack of Great Belt mussels to completely adjust to 5 psu, in contrast to the ease of Baltic Sea mussels to adjust back and forth between 6.5 and 20 psu, is remarkable and may perhaps be explained by different genotypes of Great Belt and Baltic Sea mussels.

  3. Zebra mussel mortality with chlorine

    SciTech Connect

    Van Benschoten, J.E.; Jensen, J.N.; Harrington, D.; DeGirolamo, D.J.

    1995-05-01

    The rate of mortality of the zebra mussel in response to chlorine is described by a kinetic model that combines a statistical characterization of mussel mortality with a disinfection-type modeling approach. Parameter estimates were made with nine sets of data from experiments conducted in Niagara River water. From the kinetic model, an operational diagram was constructed that describes the time to 95% mortality as a function of chlorine concentration and temperature. Either the model or the diagram can be used to assist utilities in planning chlorination treatments for controlling zebra mussels.

  4. Improving marine water quality by mussel farming: a profitable solution for Swedish society.

    PubMed

    Lindahl, Odd; Hart, Rob; Hernroth, Bodil; Kollberg, Sven; Loo, Lars-Ove; Olrog, Lars; Rehnstam-Holm, Ann-Sofi; Svensson, Jonny; Svensson, Susanne; Syversen, Ulf

    2005-03-01

    Eutrophication of coastal waters is a serious environmental problem with high costs for society globally. In eastern Skagerrak, reductions in eutrophication are planned through reduction of nitrogen inputs, but it is unclear how this can be achieved. One possible method is the cultivation of filter-feeding organisms, such as blue mussels, which remove nitrogen while generating seafood, fodder and agricultural fertilizer, thus recycling nutrients from sea to land. The expected effect of mussel farming on nitrogen cycling was modeled for the Gullmar Fjord on the Swedish west coast and it is shown that the net transport of nitrogen (sum of dissolved and particulate) at the fjord mouth was reduced by 20%. Existing commercial mussel farms already perform this service for free, but the benefits to society could be far greater. We suggest that rather than paying mussel farmers for their work that nutrient trading systems are introduced to improve coastal waters. In this context an alternative to nitrogen reduction in the sewage treatment plant in Lysekil community through mussel farming is presented. Accumulation of bio-toxins has been identified as the largest impediment to further expansion of commercial mussel farming in Sweden, but the problem seems to be manageable through new techniques and management strategies. On the basis of existing and potential regulations and payments, possible win-win solutions are suggested. PMID:15865310

  5. Heavy metals in seaducks and mussels from Misty Fjords National Monument in southeast Alaska

    USGS Publications Warehouse

    Franson, J.C.; Koehl, P.S.; Derksen, D.V.; Rothe, T.C.; Bunck, C.M.; Moore, J.F.

    1995-01-01

    Quartz Hill, in Misty Fjords National Monument near Ketchikan, Alaska, is the site of a proposed molybdenum-producing mine. To provide baseline data for use in post-development comparisons, we analyzed tissues of Barrow's goldeneyes (Bucephala islandica), common mergansers (Mergus merganser), and blue mussels (Mytilus edulis) for seven heavy metals that could potentially be released into the environment as a result of mining operations. Specimens were collected in 1980, 1981, and 1982 from two fjords likely to be used for discharge of tailings from the proposed mine and from two control fjords. Concentrations of arsenic, cadmium, copper, chromium, molybdenum, lead, and zinc were measured in soft tissues of mussels and in kidney, liver, and muscle of birds. The highest mean concentrations of metals found in bird tissues were 55.7 ppm dry weight cadmium in kidneys and 154 ppm dry weight zinc in livers of Barrow's goldeneyes. Concentrations of several metals in blue mussels differed among seasons and locations, but the most significant finding in mussels was a maximum mean cadmium concentration of 9.6 ppm dry weight, a level higher than normally found in undisturbed areas. With the exception of 104 ppm dry weight cadmium in the kidney of one common merganser and 12.7 ppm dry weight lead in the kidney of another, concentrations of other metals in seaduck and mussel tissues were low, consistent with what would be expected for a pre-development environment. Molybdenum was found in low concentrations ( 10 ppm dry weight) in all avian kidney samples and most liver samples, but was not detected in blue mussels.

  6. Birds, seals and the suspension culture of mussels in Bantry Bay, a non-seaduck area in Southwest Ireland

    NASA Astrophysics Data System (ADS)

    Roycroft, D.; Kelly, T. C.; Lewis, L. J.

    2004-12-01

    Concerns about the environmental impacts of mariculture have grown in recent years in response to the rapid expansion of the industry. The blue mussel ( Mytilus edulis) is the main product of shellfish mariculture in the Northeast Atlantic and Baltic Sea, with approximately one third of the harvest cultured using suspended longlines within sheltered marine areas. The main aim of this study was to examine the interactions, and assess the impacts (if any) of mussel suspension culture on the seabird and seal community, employing a simultaneous study of culture and control sites. The study spanned a 20-month period (from November 2001 to August 2003) and encompassed six sites in Bantry Bay (Southwest Ireland). There was no significant difference in species richness between mussel and control sites. Similarly, species diversity did not significantly differ between the mussel and control sites although control sites were generally more diverse than mussel sites, the latter particularly dominated by large numbers of Laridae. Significantly higher numbers of Phalacrocoracidae, Laridae and Alcidae were recorded in mussel sites than in control sites. However, no significant difference was found between Gaviidae or common seal ( Phoca vitulina) numbers in mussel and control sites. Seasonal patterns of abundance were similar in mussel and control sites, with peak numbers of most species groups occurring in spring. Mussel suspension culture does not appear to have an adverse effect on the abundance of seabirds or common seals in this area. The safe perching platforms provided by suspension culture floats, combined with a number of other factors, contribute to an increased abundance of a number of seabird species, particularly Laridae. The possible interactions between vertebrate predators and mussel suspension aquaculture are discussed and possible explanations for the increased seabird abundance observed in these areas are offered.

  7. Spatial organisation and biomass development after relaying of mussel seed

    NASA Astrophysics Data System (ADS)

    Capelle, Jacob J.; Wijsman, Jeroen W. M.; Schellekens, Tim; van Stralen, Marnix R.; Herman, Peter M. J.; Smaal, Aad C.

    2014-01-01

    It is not known whether and by what factors spatial heterogeneity in mussels (Mytilus edulis L.) affects mussel production in human-created mussel beds. In a field experiment, the same number of mussels was relayed on four different areas within plots of the same size, resulting in four treatments with different mussel densities. Density, individual weight and spatial structure of mussels were followed per treatment. The uniformly placed mussels on different areas redistributed into new patches, but mussels did not spread out over a larger area. Initial mussel density affected redistribution and mussel survival. At high densities mussels redistributed into a uniform matrix or in a few larger patches, that showed larger losses than at low densities, where mussels redistributed into a high number of patches. Growth rate and condition index of the mussels did not differ between treatments and no relation was found between treatment and number of foraging shore crabs, which was the major predator of mussels in this experiment. We hypothesise that the relation between initial mussel density and mussel loss after relaying is associated with redistribution, with less competition for space when mussels are positioned at the edge of a mussel patch. The very high mussel losses that we observed in the experiment within four weeks after relaying were the major factor in biomass development. Mussel bed formation concerns mussel growers and managers involved in natural mussel bed restoration. Initial mussel survival determines the success of these activities. The present study shows the effects of mussel relaying on spatial redistribution for the first time under field conditions, and underlines the importance of edge effects in understanding mussel loss in redistribution. Mussel survival after relaying will be higher when the mussels are distributed homogeneously and in relatively low density.

  8. Blue Note

    ScienceCinema

    Murray Gibson

    2010-01-08

    Argonne's Murray Gibson is a physicist whose life's work includes finding patterns among atoms. The love of distinguishing patterns also drives Gibson as a musician and Blues enthusiast."Blue" notes are very harmonic notes that are missing from the equal temperament scale.The techniques of piano blues and jazz represent the melding of African and Western music into something totally new and exciting.

  9. Blue Note

    SciTech Connect

    Murray Gibson

    2007-04-27

    Argonne's Murray Gibson is a physicist whose life's work includes finding patterns among atoms. The love of distinguishing patterns also drives Gibson as a musician and Blues enthusiast."Blue" notes are very harmonic notes that are missing from the equal temperament scale.The techniques of piano blues and jazz represent the melding of African and Western music into something totally new and exciting.

  10. MAINE MUSSEL SEED CONSERVATION AREAS

    EPA Science Inventory

    SEED shows point locations of Maine mussel seed conservation areas at 1:24,000 scale. Data for this coverage were screen digitized on a 1:24000 scale base using descriptions contained in Maine Department of Marine Resources (MDMR) rules. Coastal arcs from Maine Office of GIS 1:24...

  11. Caged mussels and semipermeable membrane devices as indicators of organic contaminant uptake in Dorchester and Duxbury Bays, Massachusetts

    SciTech Connect

    Peven, C.S.; Uhler, A.D.; Querzoli, F.J.

    1996-02-01

    An experiment to measure organic contaminant depuration by the blue mussel (Mytilus edulis) was carried out by transplanting mussels in stainless steel cages from a known contaminated site in Dorchester Bay, Massachusetts to a documented clean site in Duxbury Bay, Massachusetts approximately 30 nmi south of the original collection site. A parallel contaminant uptake experiment was performed in which mussels from Duxbury Bay were collected and deployed in similar cages in Dorchester Bay. The bivalves were collected from each transplant site at set intervals over a period of 95 days to monitor the rates and selectivity of depuration and uptake, respectively, of polynuclear atomic hydrocarbons (PAH), polychlorinated biphenyls (PCB), and chlorinated pesticides. In a related study, semipermeable membrane devices (SPMD: polyethylene bags) containing the lipid material triolein were deployed in Dorchester Bay and collected at the same frequency as the caged mussels to evaluate their effectiveness as models for estimating bioconcentration of target organic contaminants. At the Duxbury site, results suggest that the caged mussels depurated contaminants within 68 days to levels found in native animals at the site. At the Dorchester site, bivalves concentrated the contaminants to a level similar to the native M. edulis. PCB and DDT uptake rates were found to be similar between caged mussels and SPMDs; PAH uptake by the SPMDs was initially lower than by transplanted bivalves. PCB and PAH assemblages were noticeably different between bivalves and SPMDs deployed at the same site.

  12. 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.

  13. A historical assessment of coastal contamination in Birch Harbor, Maine based on the analysis of mussels collected in the 1940s and the Mussel Watch Program.

    PubMed

    Apeti, D A; Lauenstein, G G; Christensen, J D; Kimbrough, K; Johnson, W E; Kennedy, M; Grant, K G

    2010-05-01

    Coastal contamination in the 1940s was assessed based on analysis of canned blue mussels presumably collected from Birch Harbor, Maine, USA. Analytical results on legacy organic contaminants were compared to long-term National Oceanic and Atmospheric Administration (NOAA) Mussel Watch (MW) monitoring data to estimate the degree of coastal contamination before World War II (WWII) when many synthetic organic compounds were first introduced into the environment. While dieldrin and chlordane were not detected in the canned mussels, dichloro-diphenyl-trichloroethane (DDT) and hexachlorocyclohexanes (HCHs) were present at lower concentrations relative to the more recent MW data. Polychlorinated biphenyls (PCBs) and polycyclic aromatic hydrocarbons (PAHs) were detected, and the later were significantly higher in canned mussels relative to the MW data (p<0.05). Furthermore, moving average analysis applied to the MW data depicted three-phased temporal trend patterns (increase-decrease-steady state) for virtually all contaminants indicating an overall increased coastal contamination in post WWII era. PMID:20097385

  14. Environmental DNA mapping of Zebra Mussel populations

    USGS Publications Warehouse

    Amberg, Jon; Merkes, Christopher

    2016-01-01

    Environmental DNA (eDNA) has become a popular tool for detecting aquatic invasive species, but advancements have made it possible to potentially answer other questions like reproduction, movement, and abundance of the targeted organism. In this study we developed a Zebra Mussel (Dreissena polymorpha) eDNA protocol. We then determined if this assay could be used to help determine Zebra Mussel biomass in a lake with a well-established population of Zebra Mussels and a lake with an emerging population of mussels. Our eDNA assay detected DNA of Zebra Mussels but not DNA from more than 20 other species of fish and mussels, many commonly found in Minnesota waters. Our assay did not predict biomass. We did find that DNA from Zebra Mussels accumulated in softer substrates in both lakes, even though the mussels were predominately on the harder substrates. Therefore, we concluded that eDNA may be useful to detect the presence of Zebra Mussels in these lakes but our assay/approach could not predict biomass.

  15. Lipophilic toxin profiles detected in farmed and benthic mussels populations from the most relevant production zones in Southern Chile.

    PubMed

    Garcia, Carlos; Rodriguez-Unda, Nelson; Contreras, Cristóbal; Barriga, Andrés; Lagos, Néstor

    2012-01-01

    Lipophilic toxins associated with diarrhoeic toxins were found in Mytilus chilensis (Blue mussels) and Aulacomya ater (Ribbed mussels). These shellfish samples were collected from Chiloe Island, Southern Chile. The samples were tested by liquid chromatography-tandem mass spectrometry (LC-MS/MS). After the analysis, four toxins were found: DTX-1, DTX-3, YTX and PTX. All toxins were identified by comparing their HPLC retention times with those of analytical standards and confirmed by LC-MS/MS. Dinophysistoxin-1 (DTX-1) and dinophysistoxin-3 (DTX-3) toxins were the major components within the mussel extracts. Nevertheless, the percentages of these toxins differed depending on the area they were collected from and/or the sampling date. The levels detected in Butacheuques Island for okadaic acid (OA) was 267 ± 3.5 µg OA eq kg(-1) (p < 0.05) and for DTX-3 was 183.4 ± 7.5 µg kg(-1) in ribbed mussels. Pectenotoxin (PTX) and yessotoxin (YTX) were the toxins detected in minor proportions in the toxic profile of the bivalves. The maximum concentration of YTX detected in ribbed mussels was 85.2 ± 2.8 µg kg(-1) in Mechuque Island, whereas the PTX-2 level in ribbed mussels was 82.0 ± 2.4 µg kg(-1) in Cailin Island. Analogues of YTX and PTX-2 were not detected in any of the analysed mussels, which did not support the supposed presence of isomers of toxins as a result of the enzymatic metabolism of bivalves. This study found evidence proving co-occurrence of lipophilic toxins - like PTX and YTX - with diarrhoeic toxin in samples collected in Southern Chile, which is, to date, the more complex mix of lipophilic toxins ever found in mussels samples from Southern Chile. PMID:22424031

  16. 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.

  17. Zebra mussels. The assault continues

    SciTech Connect

    Lamarre, L.

    1993-09-01

    Over the past seven years, zebra mussel infestation has spread relentlessly, fouling up utility cooling intakes and other industrial operations that draw fresh water. The striped invader has flourished in all of the Great Lakes and most of the major river systems east of and including the Mississippi. It has also migrated much deeper into the South than experts anticipated and is making its way westward. Now biologists have turned up a separate, look-alike species they fear may be just as destructive. EPRI is continuing its work to improve control techniques and has published a comprehensive monitoring and control guide that outlines the best practices currently available for dealing with the mussel problem. This article reviews the results of this work.

  18. Dynamics of mussel plaque detachment.

    PubMed

    Desmond, Kenneth W; Zacchia, Nicholas A; Waite, J Herbert; Valentine, Megan T

    2015-09-14

    Mussels are well known for their ability to generate and maintain strong, long-lasting adhesive bonds under hostile conditions. Many prior studies attribute their adhesive strength to the strong chemical interactions between the holdfast and substrate. While chemical interactions are certainly important, adhesive performance is also determined by contact geometry, and understanding the coupling between chemical interactions and the plaque shape and mechanical properties is essential in deploying bioinspired strategies when engineering improved adhesives. To investigate how the shape and mechanical properties of the mussel's plaque contribute to its adhesive performance, we use a custom built load frame capable of fully characterizing the dynamics of the detachment. With this, we can pull on samples along any orientation, while at the same time measuring the resulting force and imaging the bulk deformations of the plaque as well as the holdfast-substrate interface where debonding occurs. We find that the force-induced yielding of the mussel plaque improves the bond strength by two orders of magnitude and that the holdfast shape improves bond strength by an additional order of magnitude as compared to other simple geometries. These results demonstrate that optimizing the contact geometry can play as important a role on adhesive performance as optimizing the chemical interactions as observed in other organisms and model systems. PMID:26223522

  19. Accumulation of polycyclic aromatic hydrocarbons in semipermeable membrane devices and caged mussels (Mytilus edulis L.) in relation to water column phase distribution

    SciTech Connect

    Axelman, J.; Naes, K.; Naef, C.; Broman, D.

    1999-11-01

    Semipermeable membrane devices (SPMDs) and blue mussels (Mytilus edulis L.) were deployed at a site contaminated by discharges of polycyclic aromatic hydrocarbons (PAHs) from an aluminium reduction plant, and at a reference site. The accumulation of PAHs in SPMDs versus mussels, along with the ability of the two matrices to predict contaminant concentrations in the ambient environment, were evaluated through concurrent measurements of particulate, dissolved, and colloidal PAHs in the water column. Analysis of the results showed that blue mussels were more efficient at sequestering PAHs than were SPMDs. The PAH profile (i.e,, the relative abundance of individual PAHs) in the two matrices were similar, but differed significantly from the profile in the dissolved phase. Further, back-calculation of the ambient dissolved concentrations from SPMDs indicated systematic overtrapping with increasing hydrophobicity. Calculation of in situ bioconcentration factors (BCFs) for the blue mussels at the smelter site indicated that uptake via particles or from colloids dominated over direct uptake from the dissolved phase, as opposed to the reference site. The in situ BCFs differed markedly from literature values, which implies that the use of mussels to predict ambient concentrations would require that site-specific BCFs be applied.

  20. 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)

  1. Research continues on zebra mussel control

    SciTech Connect

    Not Available

    1993-04-01

    Researchers are working on many fronts to learn methods for controlling and combatting zebra mussels, a species of mussel that can attach to the inside of water intakes at hydroelectric and thermal power plants, and can reduce or block water flow. Biologists at the University of Toledo in Ohio report that compounds from the African soapberry plant called lemmatoxins are lethal to zebra mussels. In laboratory tests, researchers have determined 1 to 2 milligrams of purified lemmatoxins per liter will kill the mussels. In field tests, biologist Harold Lee flushed water through a mussel-infested pipe. He found that the berry extract killed mussels in four to eight hours, making continuous treatment of water intake pipes unnecessary, according to a report in New Scientists. The University of Toledo participated in another project, funded by the American Water Works Association Research Foundation. That project team included the cities of Toledo and Cleveland, Ohio, Finkbeiner, Pettis Strout, Ltd. consulting engineers, and researchers from Ohio's Case Western Reserve University. The team identified a chemical oxidant, sodium hypochlorite, as a cost-effective agent for controlling zebra mussels at water treatment plant intakes. Toledo has used the sodium hypochlorite and reports the chemical has cleared colonies of zebra mussels that had attached to the intake of its water treatment plant.

  2. Blue gods, blue oil, and blue people.

    PubMed

    Fairbanks, V F

    1994-09-01

    Studies of the composition of coal tar, which began in Prussia in 1834, profoundly affected the economies of Germany, Great Britain, India, and the rest of the world, as well as medicine and surgery. Such effects include the collapse of the profits of the British indigo monopoly, the growth in economic power of Germany based on coal tar chemistry, and an economic crisis in India that led to more humane tax laws and, ultimately, the independence of India and the end of the British Empire. Additional consequences were the development of antiseptic surgery and the synthesis of a wide variety of useful drugs that have eradicated infections and alleviated pain. Many of these drugs, particularly the commonly used analgesics, sulfonamides, sulfones, and local anesthetics, are derivatives of aniline, originally called "blue oil" or "kyanol." Some of these aniline derivatives, however, have also caused aplastic anemia, agranulocytosis, and methemoglobinemia (that is, "blue people"). Exposure to aniline drugs, particularly when two or three aniline drugs are taken concurrently, seems to be the commonest cause of methemoglobinemia today. PMID:8065194

  3. Zebra mussels anchor byssal threads faster and tighter than quagga mussels in flow.

    PubMed

    Peyer, Suzanne M; McCarthy, Alice J; Lee, Carol Eunmi

    2009-07-01

    While the invasive zebra mussel Dreissena polymorpha has rapidly spread throughout the Great Lakes and inland waterways, it is being displaced by the quagga mussel Dreissena bugensis in shallow water habitats. However, zebra mussels remain dominant in areas with higher water velocity. We hypothesized that the persistence of zebra over quagga mussels in habitats with higher water velocity might result from greater rate and strength of byssal thread attachment. We examined whether zebra mussels relative to quagga mussels have: (1) higher byssal thread synthesis rate, (2) lower dislodgment in flow and (3) greater mechanical force required for detachment from substrate. Specifically, we examined byssal thread synthesis rate and dislodgment of both species in response to water velocities of 0, 50, 100 and 180 cm s(-1). Byssal thread synthesis rate was significantly higher for zebra than for quagga mussels at all velocities. Dislodgment from the substrate increased for both species with increasing velocity but was significantly lower for zebra than for quagga mussels. We also tested the mechanical force to detach mussels after short (32 h) and long (two and three months) periods of attachment on hard substrate. Detachment force was significantly higher for zebra than for quagga mussels only after short-term attachment. Higher byssal thread synthesis rate in zebra mussels was a likely factor that minimized their dislodgment in flow and increased short-term attachment strength. Differences in byssal thread synthesis rate between the two species might partly account for the ability of zebra mussels to maintain dominance over quagga mussels in habitats with high velocities. PMID:19525429

  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. PMID:25910461

  5. Occurrence of polychlorinated biphenyls and polybrominated diphenyl ethers in green mussels (Perna viridis) from Singapore, Southeast Asia.

    PubMed

    Bayen, Stéphane; Thomas, Gareth Owen; Lee, Hian Kee; Obbard, Jeffrey Philip

    2003-10-01

    The green mussel, Perna viridis, was used in this study to measure levels of polychlorinated biphenyls (PCBs) and, for the first time, polybrominated diphenyl ethers (PBDE) in the marine environment. Samples were collected from eight different locations in the coastal waters of Singapore between April and May 2002. Forty-one PCB and 21 PBDE congeners were quantified by gas chromatography-mass spectrometry and were all positively detected in the mussel tissues. Total concentrations in green mussel tissues ranged from 6.1 to 82 ng/g and 2.0 to 38 ng/g on a dry-weight basis for PCBs and PBDEs, respectively. Such levels reflect the ubiquity of these persistent organic pollutants in a tropical marine environment. Principal component analysis was applied to the PCB data and revealed similarities in the congener composition of mussel tissues to that of the commercial PCB mixture, Aroclor 1254. The PBDE levels, to date, were approximately one order of magnitude greater than the upper concentrations reported for blue mussel (Mytilus edulis) tissues in Europe. At some sampling sites, the congener composition of PBDEs in P. viridis tissues indicated recent exposure to a commercial pentabrominated flame retardant. PMID:14552008

  6. Environmentally Safe Control of Zebra Mussel Fouling

    SciTech Connect

    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.

  7. Antifouling bastadin congeners target mussel phenoloxidase and complex copper(II) ions.

    PubMed

    Bayer, Mirko; Hellio, Claire; Maréchal, Jean-Philippe; Frank, Walter; Lin, Wenhan; Weber, Horst; Proksch, Peter

    2011-12-01

    Synthetically prepared congeners of sponge-derived bastadin derivatives such as 5,5'-dibromohemibastadin-1 (DBHB) that suppress the settling of barnacle larvae were identified in this study as strong inhibitors of blue mussel phenoloxidase that is involved in the firm attachment of mussels to a given substrate. The IC₅₀ value of DBHB as the most active enzyme inhibitor encountered in this study amounts to 0.84 μM. Inhibition of phenoloxidase by DBHB is likely due to complexation of copper(II) ions from the catalytic centre of the enzyme by the α-oxo-oxime moiety of the compound as shown here for the first time by structure activity studies and by X-ray structure determination of a copper(II) complex of DBHB. PMID:21547349

  8. Absence of histophatological response to cadmium in gill and digestive diverticula of the mussel, Mytilus edulis

    SciTech Connect

    Giraud, A.S.; Webster, L.K.; Fabris, J.G.; Collett, L.C.; Yeomans, N.D.

    1986-01-01

    The blue mussel (Mytilus edulis) has been proposed for use as a sentinel organism to monitor the effects of marine pollution (Goldberg et al., 1978). Recently, there has been interest in quantifying histopathological changes in mussel tissues, as one indicator of pollution-induced stress. Cadmium is a common and toxic aquatic pollutant. Gill and digestive diverticula have been shown to be major sites of cadmium detoxification. In these same tissues, histopathological changes have been demonstrated after exposure to crude oil and to an oil dispersant. However, whether similar morphological changes are induced by heavy metals, such as cadmium, is not known. In this study, the authors have assessed the cellular effects of sublethal concentrations of cadmium on the gill and digestive diverticula of Mytilus.

  9. Bioaccumulation of trace metals in mussel (Mytilus galloprovincialis) from Mali Ston Bay during DSP toxicity episodes.

    PubMed

    Ujević, Ivana; Vuletić, Nenad; Lušić, Jelena; Nazlić, Nikša; Kušpilić, Grozdan

    2015-01-01

    The Croatian National Monitoring Program revealed the presence of Diarrhetic Shellfish Poisoning (DSP) toxicity in Mediterranean blue mussel (Mytilus galloprovincialis) from breeding farms in southern Adriatic Sea through January to June 2011. The mouse bioassay tests (MBA; at the time the official method for DSP toxins) were accompanied by atypical symptomatology in the animals and this caused doubts about the assay results. Consequently, in parallel studies reported here, the concentration of Cd, Cr, Cu, Ni, Pb and Zn in soft tissue of DSP positive and negative mussels samples was determined. Cd, Cr, Zn and Ni show higher values in approximately 75% of the DSP positive samples, whereas for Pb and Cr the values were 26% and 34%, respectively. This trend was unchanged during the whole observation period. PMID:26193253

  10. Temporal consistency of spatial pattern in growth of the mussel, Mytilus edulis: Implications for predictive modelling

    NASA Astrophysics Data System (ADS)

    Bergström, Per; Lindegarth, Susanne; Lindegarth, Mats

    2013-10-01

    Human pressures on coastal seas are increasing and methods for sustainable management, including spatial planning and mitigative actions, are therefore needed. In coastal areas worldwide, the development of mussel farming as an economically and ecologically sustainable industry requires geographic information on the growth and potential production capacity. In practice this means that coherent maps of temporally stable spatial patterns of growth need to be available in the planning process and that maps need to be based on mechanistic or empirical models. Therefore, as a first step towards development of models of growth, we assessed empirically the fundamental requirement that there are temporally consistent spatial patterns of growth in the blue mussel, Mytilus edulis. Using a pilot study we designed and dimensioned a transplant experiment, where the spatial consistency in the growth of mussels was evaluated at two resolutions. We found strong temporal and scale-dependent spatial variability in growth but patterns suggested that spatial patterns were uncoupled between growth of shell and that of soft tissue. Spatial patterns of shell growth were complex and largely inconsistent among years. Importantly, however, the growth of soft tissue was qualitatively consistent among years at the scale of km. The results suggest that processes affecting the whole coastal area cause substantial differences in growth of soft tissue among years but that factors varying at the scale of km create strong and persistent spatial patterns of growth, with a potential doubling of productivity by identifying the most suitable locations. We conclude that the observed spatial consistency provides a basis for further development of predictive modelling and mapping of soft tissue growth in these coastal areas. Potential causes of observed patterns, consequences for mussel-farming as a tool for mitigating eutrophication, aspects of precision of modelling and sampling of mussel growth as well

  11. Molecular interactions of mussel protective coating protein, mcfp-1, from Mytilus californianus.

    PubMed

    Lu, Qingye; Hwang, Dong Soo; Liu, Yang; Zeng, Hongbo

    2012-02-01

    Protective coating of the byssus of mussels (Mytilus sp.) has been suggested as a new paradigm of medical coating due to its high extensibility and hardness co-existence without their mutual detriment. The only known biomacromolecule in the extensible and tough coating on the byssus is mussel foot protein-1 (mfp-1), which is made up with positively charged residues (~20 mol%) and lack of negatively charged residues. Here, adhesion and molecular interaction mechanisms of Mytilus californianus foot protein-1 (mcfp-1) from California blue mussel were investigated using a surface forces apparatus (SFA) in buffer solutions of different ionic concentrations (0.2-0.7 M) and pHs (3.0-5.5). Strong and reversible cohesion between opposed positively charged mcfp-1 films was measured in 0.1 M sodium acetate buffer with 0.1 M KNO(3). Cohesion of mcfp-1 was gradually reduced with increasing the ionic strength, but was not changed with pH variations. Oxidation of 3,4-dihydroxyphenylalanine (DOPA) residues of mcfp-1, a key residue for adhesive and coating proteins of mussel, didn't change the cohesion strength of mcfp-1 films, but the addition of chemicals with aromatic groups (i.e., aspirin and 4-methylcatechol) increased the cohesion. These results suggest that the cohesion of mcfp-1 films is mainly mediated by cation-π interactions between the positively charged residues and benzene rings of DOPA and other aromatic amino acids (~20 mol% of total amino acids of mcfp-1), and π-π interactions between the phenyl groups in mcfp-1. The adhesion mechanism obtained for the mcfp-1 proteins provides important insight into the design and development of functional biomaterials and coatings mimicking the extensible and robust mussel cuticle coating. PMID:22138031

  12. Geographical distribution of non-PBDE-brominated flame retardants in mussels from Asian coastal waters.

    PubMed

    Isobe, Tomohiko; Ogawa, Shohei P; Ramu, Karri; Sudaryanto, Agus; Tanabe, Shinsuke

    2012-09-01

    Hexabromocyclododecanes (HBCDs), 1,2-bis(2,4,6-tribromophenoxy) ethane (BTBPE), and decabromodiphenyl ethane (DBDPE) used as alternatives for polybrominated diphenyl ethers (PBDEs) are also persistent in the environment as PBDEs. Limited information on these non-PBDE brominated flame retardants (BFRs) is available; in particular, there are only few publications on environmental pollution by these contaminants in the coastal waters of Asia. In this regard, we investigated the contamination status of HBCDs, BTBPE, and DBDPE in the coastal waters of Asia using mussels as a bioindicator. Concentrations of HBCDs, BTBPE, and DBDPE were determined in green (Perna viridis) and blue mussels (Mytilus edulis) collected from the coastal areas in Cambodia, China (mainland), SAR China (Hong Kong), India, Indonesia, Japan, Malaysia, the Philippines, and Vietnam on 2003-2008. BTBPE and DBDPE were analyzed using GC-MS, whereas HBCDs were determined by LC-MS/MS. HBCDs, BTBPE, and DBDPE were found in mussels at levels ranging from <0.01 to 1,400, <0.1 to 13, and <0.3 to 22 ng/g lipid wt, respectively. Among the three HBCD diastereoisomers, α-HBCD was the dominant isomer followed by γ- and β-HBCDs. Concentrations of HBCDs and DBDPE in mussels from Japan and Korea were higher compared to those from the other Asian countries, indicating extensive usage of these non-PBDE BFRs in Japan and Korea. Higher levels of HBCDs and DBDPE than PBDEs were detected in some mussel samples from Japan. The results suggest that environmental pollution by non-PBDE BFRs, especially HBCDs in Japan, is ubiquitous. This study provides baseline information on the contamination status of these non-PBDE BFRs in the coastal waters of Asia. PMID:22875421

  13. Controlling zebra mussel infestations at hydroelectric plants

    SciTech Connect

    Sblendorio, R.P.; Malinchock, J.C. ); Claudi, R. )

    1991-07-01

    U.S. and Canadian utilities in the great lakes area have adopted techniques to temporarily prevent infestation of the zebra mussel in their hydro facilities, but are still looking for more permanent solutions.

  14. Introduced species, zebra mussels in North America

    USGS Publications Warehouse

    Schloesser, Don W.

    1995-01-01

    The discovery of zebra mussels in North America in 1988 raised concern for water users because the species became abundant enough to obstruct the flow of water in human-made structures such as pipes and screens. This work reviews the biology, distribution, and impacts of zebra mussels in the context of its discovery in the Laurentian Great Lakes and its impending spread to most surface waters of North America.

  15. Stravation tolerance of zebra mussels, Dreissena polymorpha

    SciTech Connect

    Chase, R.; McMahon, R.F.

    1995-06-01

    Samples of zebra mussels, Dreissena polymorpha (n=30), were held without food at 5{degrees}, 15{degrees}, or 25{degrees}C and examined daily for mortality. Further samples of 210 mussels at each test temperature were periodically subsampled (n=10) throughout the starvation period. Tissues and shells of sampled specimens were dried to a constant weight. Zebra mussels held at 25{degrees}C experienced 100% mortality after 166 days of starvation while mussels at 15{degrees}C experienced 100% mortality after 545 days. A mortality of 60% was recorded in mussels after 524 days at 5{degrees}C. Dry shell weight (DSW) of starving zebra mussels at 25{degrees}C remained constant; at 15{degrees}C, DSW increased, likely due to deposition of new shell without increase in length. At 5{degrees}C DSW decreased possibly due to the high solubility of shell calcium carbonate at this low temperature. Dry tissue weight (DTW) decreased linearly during starvation at all test temperatures with the rate of DTW loss increasing at higher holding temperatures. Estimated percent tissue biomass reductions in a 20 mm long starved individual were 73.8% after 132 days at 25{degrees}C, 68.9% after 545 days at 15{degrees}C and 61.6% after 516 days at 5{degrees}C. When DTW loss rates were converted to O{sub 2} consumption rates (O{sub 2}), the O{sub 2} of a 20 mm long mussel was estimated to be 22.2% of prestarvation O{sub 2} at 25{degrees}C, 11.0% at 15{degrees}C and 10.2% at 5{degrees}C. Major reduction in metabolic demand in starving zebra mussels at low temperatures allows overwintering without appreciable loss of organic energy stores.

  16. Radium-226 accumulation in Florida freshwater mussels

    USGS Publications Warehouse

    Brenner, M.; Smoak, J.M.; Leeper, D.A.; Streubert, M.; Baker, S.M.

    2007-01-01

    Selected lakes in Hillsborough County, Florida have been hydrologically augmented with groundwater to offset stage declines caused by excessive pumping of the Floridan Aquifer. Augmentation water can be relatively rich in 226Ra (>5 decays per minute [dpm] L-1). We measured 226Ra activities in shells and soft tissues of adult bivalve molluscs (Elliptio cf. buckleyi) from groundwater-augmented and nonaugmented lakes to assess bioaccumulation of 226Ra by mussels. Mussels from augmented lakes displayed higher 226Ra in both shells and tissues than did mussels from nonaugmented lakes. Within a sample, 226Ra activity in Elliptio tissues was higher than the value measured in shells. Highest activities were found in a composite mussel sample (n = 6) from an augmented lake; soft tissue activity was 619 ?? 33 dpm g-1 dry weight and shell activity was 147 ?? 7 dpm g-1 g dry weight. Large mussels displayed greater activities in soft tissues and shells than did small mussels. We transplanted animals from a nonaugmented lake into a groundwater-augmented water body. 226Ra activity in dry tissue rose from 32 ?? 1 to 196 ?? 2 dpm g-1 within 2 months. When 226Ra-rich mussels (232 ?? 2 dpm g-1) from the augmented lake were transferred to the nonaugmented lake, they showed no significant 226Ra loss over the 69-d experiment. Large Elliptio mussels concentrated 226Ra in their soft tissues to levels about 1,000 to 25,000 times concentrations in lake water. Pumping of groundwater in Florida for residential, agricultural, and industrial use contributes dissolved 226Ra to some surface water bodies, where it can be bioaccumulated by bivalve molluscs. ?? 2007, by the American Society of Limnology and Oceanography, Inc.

  17. Danish auroral science history

    NASA Astrophysics Data System (ADS)

    Stauning, P.

    2011-01-01

    Danish auroral science history begins with the early auroral observations made by the Danish astronomer Tycho Brahe during the years from 1582 to 1601 preceding the Maunder minimum in solar activity. Included are also the brilliant observations made by another astronomer, Ole Rømer, from Copenhagen in 1707, as well as the early auroral observations made from Greenland by missionaries during the 18th and 19th centuries. The relations between auroras and geomagnetic variations were analysed by H. C. Ørsted, who also played a vital role in the development of Danish meteorology that came to include comprehensive auroral observations from Denmark, Iceland and Greenland as well as auroral and geomagnetic research. The very important auroral investigations made by Sophus Tromholt are outlined. His analysis from 1880 of auroral observations from Greenland prepared for the significant contributions from the Danish Meteorological Institute, DMI, (founded in 1872) to the first International Polar Year 1882/83, where an expedition headed by Adam Paulsen was sent to Greenland to conduct auroral and geomagnetic observations. Paulsen's analyses of the collected data gave many important results but also raised many new questions that gave rise to auroral expeditions to Iceland in 1899 to 1900 and to Finland in 1900 to 1901. Among the results from these expeditions were 26 unique paintings of the auroras made by the artist painter, Harald Moltke. The expedition to Finland was headed by Dan la Cour, who later as director of the DMI came to be in charge of the comprehensive international geomagnetic and auroral observations made during the Second International Polar Year in 1932/33. Finally, the article describes the important investigations made by Knud Lassen during, among others, the International Geophysical Year 1957/58 and during the International Quiet Sun Year (IQSY) in 1964/65. With his leadership the auroral and geomagnetic research at DMI reached a high international

  18. Steam treatment of zebra mussels

    SciTech Connect

    Tsou, J.; Rybarik, D.L.; Thiel, J.

    1995-06-01

    Steam injection into intake bays is a nonchemical method to control zebra mussels. This technique was demonstrated at Dairyland Power Cooperative`s J.P. Madgett Station located in Alma, Wisconsin. The project was funded by the EPRI Zebra Mussel Consortium which includes: Dairyland Power Cooperative, Central Illinois Public Service, Duke Power, Illinois Power Company, PSI Energy, Public Service Electric & Gas, and Tennessee Valley Authority. This technique can be used by other power plants with a similar problem. A contract between Electric Power Research Institute (EPRI) and Stone & Webster Engineering Corporation (Stone & Webster) was initiated in August 1994. The steam treatments were performed at the J.P. Madgett intake in Alma, Wisconsin, on September 14 and 18, 1994. The J.P. Madgett Station has two water intake bays with storage capacities of approximately 295,000 and 265,000 gallons, respectively. Each intake can be isolated, permitting either full or reduced generation depending on river temperature conditions. In addition to the intake bays, the outside fire protection loop and hydrants were also treated with the hot water from one of the bays. This paper presents the process design, piping and steam educator configurations, portable industrial boiler sizing and description, and the thermocouples to monitor the water temperature in the intake bay. The biological mortality and control test protocol and treatment results are also presented. Treatment effectiveness was 100%; however, equipment installation and operation was more problematic than anticipated. A generic computer program is developed and verified using thermal data from the test. The PC program will allow other utilities to size the boiler and estimate the heat losses from an intake bay. The treatment also provided valuable information that simplifies future applications and provides for more realistic design and installation schedules and costs.

  19. Is the body condition of the invasive zebra mussel (Dreissena polymorpha) enhanced through attachment to native freshwater mussels (Bivalvia, Unionidae)?

    PubMed

    Pilotto, Francesca; Sousa, Ronaldo; Aldridge, David C

    2016-05-15

    The invasion of zebra mussels, Dreissena polymorpha, into Western Europe and North America has driven widespread ecological change. Attachment of zebra mussels to the shell of native unionoid mussels has resulted in reductions in unionoid abundance and, in extreme cases, their localised extirpations. While the impacts of zebra mussels on infested unionoids are well documented, the possible benefits of the association to the zebra mussel have been little considered. We collected zebra mussels attached to unionoids and to inanimate structures. Zebra mussels attached to unionoids had significantly larger shells, higher standardized body mass and glycogen content than those attached to inanimate substrates, suggesting that D. polymorpha benefits from settling upon unionoids. The body condition of individual zebra mussels was negatively correlated with the number of zebra mussels attached to the unionoid, indicating intraspecific competition. Therefore, zebra mussels seem positively affected through attachment to unionoid mussels, but that these benefits decrease at higher densities of fouling. This association may offer advantages to the spread of zebra mussels within unionoid-rich systems, especially at sites with soft substrates and at the early stages of the invasion process where intraspecific competition is likely to be lower and benefits to the zebra mussels are higher. PMID:26925735

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

    USGS Publications Warehouse

    Nalepa, Thomas F., (Edited By); 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.

  1. 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.

  2. Cheating the Locals: Invasive Mussels Steal and Benefit from the Cooling Effect of Indigenous Mussels

    PubMed Central

    Lathlean, Justin A.; Seuront, Laurent; McQuaid, Christopher D.; Ng, Terence P. T.; Zardi, Gerardo I.; Nicastro, Katy R.

    2016-01-01

    The indigenous South African mussel Perna perna gapes during periods of aerial exposure to maintain aerobic respiration. This behaviour has no effect on the body temperatures of isolated individuals, but when surrounded by conspecifics, beneficial cooling effects of gaping emerge. It is uncertain, however, whether the presence of the invasive mussel Mytilus galloprovincialis limits the ability of P. perna for collective thermoregulation. We investigated whether varying densities of P. perna and M. galloprovincialis influences the thermal properties of both natural and artificial mussel beds during periods of emersion. Using infrared thermography, body temperatures of P. perna within mixed artificial beds were shown to increase faster and reach higher temperatures than individuals in conspecific beds, indicating that the presence of M. galloprovincialis limits the group cooling effects of gaping. In contrast, body temperatures of M. galloprovincialis within mixed artificial mussel beds increased slower and exhibited lower temperatures than for individuals in beds comprised entirely of M. galloprovincialis. Interestingly, differences in bed temperatures and heating rates were largely dependent on the size of mussels, with beds comprised of larger individuals experiencing less thermal stress irrespective of species composition. The small-scale patterns of thermal stress detected within manipulated beds were not observed within naturally occurring mixed mussel beds. We propose that small-scale differences in topography, size-structure, mussel bed size and the presence of organisms encrusting the mussel shells mask the effects of gaping behaviour within natural mussel beds. Nevertheless, the results from our manipulative experiment indicate that the invasive species M. galloprovincialis steals thermal properties as well as resources from the indigenous mussel P. perna. This may have significant implications for predicting how the co-existence of these two species may

  3. Cheating the Locals: Invasive Mussels Steal and Benefit from the Cooling Effect of Indigenous Mussels.

    PubMed

    Lathlean, Justin A; Seuront, Laurent; McQuaid, Christopher D; Ng, Terence P T; Zardi, Gerardo I; Nicastro, Katy R

    2016-01-01

    The indigenous South African mussel Perna perna gapes during periods of aerial exposure to maintain aerobic respiration. This behaviour has no effect on the body temperatures of isolated individuals, but when surrounded by conspecifics, beneficial cooling effects of gaping emerge. It is uncertain, however, whether the presence of the invasive mussel Mytilus galloprovincialis limits the ability of P. perna for collective thermoregulation. We investigated whether varying densities of P. perna and M. galloprovincialis influences the thermal properties of both natural and artificial mussel beds during periods of emersion. Using infrared thermography, body temperatures of P. perna within mixed artificial beds were shown to increase faster and reach higher temperatures than individuals in conspecific beds, indicating that the presence of M. galloprovincialis limits the group cooling effects of gaping. In contrast, body temperatures of M. galloprovincialis within mixed artificial mussel beds increased slower and exhibited lower temperatures than for individuals in beds comprised entirely of M. galloprovincialis. Interestingly, differences in bed temperatures and heating rates were largely dependent on the size of mussels, with beds comprised of larger individuals experiencing less thermal stress irrespective of species composition. The small-scale patterns of thermal stress detected within manipulated beds were not observed within naturally occurring mixed mussel beds. We propose that small-scale differences in topography, size-structure, mussel bed size and the presence of organisms encrusting the mussel shells mask the effects of gaping behaviour within natural mussel beds. Nevertheless, the results from our manipulative experiment indicate that the invasive species M. galloprovincialis steals thermal properties as well as resources from the indigenous mussel P. perna. This may have significant implications for predicting how the co-existence of these two species may

  4. Molecular mechanics of mussel adhesion proteins

    NASA Astrophysics Data System (ADS)

    Qin, Zhao; Buehler, Markus J.

    2014-01-01

    Mussel foot protein (mfp), a natural glue produced by marine mussel, is an intriguing material because of its superior ability for adhesion in various environments. For example, a very small amount of this material is sufficient to affix a mussel to a substrate in water, providing structural support under extreme forces caused by the dynamic effects of waves. Towards a more complete understanding of its strength and underwater workability, it is necessary to understand the microscropic mechanisms by which the protein structure interacts with various substrates. However, none of the mussel proteins' structure is known, preventing us from directly using atomistic modeling to probe their structural and mechanical properties. Here we use an advanced molecular sampling technique to identify the molecular structures of two mussel foot proteins (mfp-3 and mfp-5) and use those structures to study their mechanics of adhesion, which is then incorporated into a continuum model. We calculate the adhesion energy of the mussel foot protein on a silica substrate, compute the adhesion strength based on results obtained from molecular modeling, and compare with experimental data. Our results show good agreement with experimental measurements, which validates the multiscale model. We find that the molecular structure of the folded mussel foot protein (ultimately defined by its genetic sequence) favors strong adhesion to substrates, where L-3,4-dihydroxyphenylalanine (or DOPA) protein subunits work in a cooperative manner to enhance adhesion. Our experimental data suggests a peak attachment force of 0.4±0.1 N, which compares favorably with the prediction from the multiscale model of Fc=0.21-0.33 N. The principles learnt from those results could guide the fabrication of new interfacial materials (e.g. composites) to integrate organic with inorganic surfaces in an effective manner.

  5. The Blue Bottle Revisited.

    ERIC Educational Resources Information Center

    Vandaveer, Walter R., IV; Mosher, Mel

    1997-01-01

    Presents a modification of the classic Blue Bottle demonstration that involves the alkaline glucose reduction of methylene blue. Uses other indicators in the classic Blue Bottle to produce a rainbow of colors. (JRH)

  6. 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.

  7. Expression and functional analysis of mussel taurine transporter, as a key molecule in cellular osmoconforming.

    PubMed

    Hosoi, Masatomi; Takeuchi, Kazuharu; Sawada, Hideki; Toyohara, Haruhiko

    2005-11-01

    Most aquatic invertebrates adapt to environmental osmotic changes primarily by the cellular osmoconforming process, in which osmolytes accumulated in their cells play an essential role. Taurine is one of the most widely utilized osmolytes and the most abundant in many molluscs. Here, we report the structure, function and expression of the taurine transporter in the Mediterranean blue mussel (muTAUT), as a key molecule in the cellular osmoconforming process. Deduced amino acid sequence identity among muTAUT and vertebrate taurine transporters is lower (47-51%) than that among vertebrate taurine transporters (>78%). muTAUT has a lower affinity and specificity for taurine and a requirement for higher NaCl concentration than vertebrate taurine transporters. This seems to reflect the internal environment of the mussel; higher NaCl and taurine concentrations. In addition to the hyperosmotic induction that has been reported for cloned taurine transporters, the increase in muTAUT mRNA was unexpectedly observed under hypoosmolality, which was depressed by the addition of taurine to ambient seawater. In view of the decrease in taurine content in mussel tissue under conditions of hypoosmolality reported previously, our results lead to the conclusion that muTAUT does not respond directly to hypoosmolality, but to the consequent decrease in taurine content. By immunohistochemistry, intensive expression of muTAUT was observed in the gill and epithelium of the mantle, which were directly exposed to intensive osmotic changes of ambient seawater. PMID:16272243

  8. 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.

  9. Asia-Pacific mussel watch for emerging pollutants: Distribution of synthetic musks and benzotriazole UV stabilizers in Asian and US coastal waters.

    PubMed

    Nakata, Haruhiko; Shinohara, Ryu-Ichi; Nakazawa, Yusuke; Isobe, Tomohiko; Sudaryanto, Agus; Subramanian, Annamalai; Tanabe, Shinsuke; Zakaria, Mohamad Pauzi; Zheng, Gene J; Lam, Paul K S; Kim, Eun Young; Min, Byung-Yoon; We, Sung-Ug; Viet, Pham Hung; Tana, Touch Seang; Prudente, Maricar; Frank, Donnell; Lauenstein, Gunnar; Kannan, Kurunthachalam

    2012-10-01

    We analyzed 68 green and blue mussels collected from Cambodia, China, Hong Kong, India, Indonesia, Japan, Korea, Malaysia, Philippines, Vietnam and the USA during 2003 and 2007, to elucidate the occurrence and widespread distributions of emerging pollutants, synthetic musks and benzotriazole UV stabilizers (BUVSs) in Asia-Pacific coastal waters. Synthetic musks and BUVSs were detected in mussels from all countries, suggesting their ubiquitous contamination and widespread distribution. High concentrations of musks and BUVSs were detected in mussels from Japan and Korea, where the levels were comparable or greater than those of PCBs, DDTs and PBDEs. Significant correlations were found between the concentrations of HHCB and AHTN, and also between the concentrations of UV-327 and UV-328, which suggest similar sources and compositions of these compounds in commercial and industrial products. To our knowledge, this is the first study of large-scale monitoring of synthetic musks and BUVSs in Asia-Pacific coastal waters. PMID:22910332

  10. Distribution of persistent organic pollutants (POPs) in cultured mussels from the Croatian coast of the Adriatic Sea.

    PubMed

    Herceg-Romanić, Snježana; Kljaković-Gašpić, Zorana; Klinčić, Darija; Ujević, Ivana

    2014-11-01

    In this study we investigated the distribution of 7 organochlorine pesticides (OCPs) and 17 polychlorinated biphenyl (PCBs) congeners in the edible tissue of the blue mussels (Mytilusgalloprovincialis) collected at 15 shellfish breeding farms and 1 harvesting area along the Croatian Adriatic coast. All analyzed OCPs were found in all samples (0.011-1.47 ng g(-)(1) w.wt.). Concentrations of PCB congeners in positive samples ranged between 0.007 and 7.66 ng g(-)(1) w.wt. The most abundant compounds were γ-HCH, PCB-138 and PCB-153. Overall levels of PCBs and OCPs were in the lower end of the concentration ranges reported in literature. Significant differences of all contaminants were recorded between seasons, with higher values in the warmer part of the year. Results of the evaluation of the risks to human health associated with consumption of the mussels containing organic contaminants suggest that the levels of these compounds in mussels do not pose any threat for consumers of cultivated mussels. PMID:25113185

  11. 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

  12. 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.

  13. Chlorine dioxide treatment for zebra mussel control

    SciTech Connect

    Rybarik, D.; Byron, J.; Germer, M.

    1995-06-01

    Chlorine is recognized and commonly used biocide for power plant cooling water and service water treatment programs, including the control of zebra mussels. Chlorine dioxide has recently become a popular method of zebra mussel control because of its economy, safety, environmental acceptability, and effectiveness when compared to other mussel control methods. This control technique was recently demonstrated at Dairyland Power Cooperative`s Alma Generating Station on the east bank of the upper Mississippi River in Alma, Wisconsin. The project was assisted with EPRI Tailored Collaboration Program funds. The Dairyland Power Alam Generating Station consists of five generating units that utilize raw, untreated Mississippi River water for condenser, circulating, and service water supplies. The first units were built in 1947, with the final and largest unit being completed in 1960. Total station generating capacity is 200 MW. Because of recent increases in the zebra mussel density at the station intake, Dairyland Power selected the team of Nalco and Rio Linda to perform a chlorine dioxide treatment of the station`s new water systems to eradicate and control the mussels before their presence created operational difficulties. This paper will present the results of the treatment including treatment theory, design and construction of the treatment system, the method of chlorine dioxide generation, treatment concentration, analytical methods o monitoring chlorine dioxide generation, residuals and trihalomethane (THM) concentrations, protocol for monitoring treatment mortality, and the effects of chlorine dioxide and detoxification on other water chemistry parameters and equipment materials. The goal of this paper is to inform and assist users with establishing consistent and uniform practices for safely utilizing and monitoring chlorine dioxide in the eradication and control of zebra mussels.

  14. Zebra mussels enter the compost pile

    SciTech Connect

    Not Available

    1992-08-01

    Zebra mussels, introduced accidentally into the Great Lakes, are overpopulating at phenomenal rates, especially in Lake Erie, where they damage oyster beds, foster excessive algae growth and cling to boats. They also clog the intake pipes of city water systems and power generating plants. The expense of cleaning intake screens is considerable, since they have to be physically removed and cleaned. Then the mussels must be disposed of, costing some power plants as much as $50,000 a year to landfill, says Wayne Koser of the Michigan Department of Natural Resources.

  15. A modeling study on the hydrodynamics of a coastal embayment occupied by mussel farms (Ria de Ares-Betanzos, NW Iberian Peninsula)

    NASA Astrophysics Data System (ADS)

    Duarte, Pedro; Alvarez-Salgado, Xosé Antón; Fernández-Reiriz, Maria José; Piedracoba, Silvia; Labarta, Uxío

    2014-06-01

    The present study suggests that both under upwelling and downwelling winds, the residual circulation of Ria de Ares-Betanzos remains positive with a strong influence from river discharge and a positive feedback from wind, unlike what is generally accepted for Galician rias. Furthermore, mussel cultivation areas may reduce residual velocities by almost 40%, suggesting their potential feedbacks on food replenishment for cultivated mussels. The Ria de Ares-Betanzos is a partially stratified estuary in the NW Iberian upwelling system where blue mussels are extensively cultured on hanging ropes. This type of culture depends to a large extent on water circulation and residence times, since mussels feed on suspended particles. Therefore, understanding the role of tides, continental runoff, and winds on the circulation of this embayment has important practical applications. Furthermore, previous works have emphasized the potential importance of aquaculture leases on water circulation within coastal ecosystems, with potential negative feedbacks on production carrying capacity. Here we implemented and validated a 3D hydrodynamic numerical model for the Ria de Ares-Betanzos to (i) evaluate the relative importance of the forcing agents on the circulation within the ria and (ii) estimate the importance of culture leases on circulation patterns at the scale of the mussel farms from model simulations. The model was successfully validated with empirical current velocity data collected during July and October 2007 using an assortment of efficiency criteria. Model simulations were carried out to isolate the effects of wind and river flows on circulation patterns.

  16. 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.

  17. Thermal criteria for early life stage development of the winged mapleleaf mussel (Quadrilla fragosa)

    USGS Publications Warehouse

    Steingraeber, M.T.; Bartsch, M.R.; Kalas, J.E.; Newton, T.J.

    2007-01-01

    The winged mapleleaf mussel [Quadrula fragosa (Conrad)] is a Federal endangered species. Controlled propagation to aid in recovering this species has been delayed because host fishes for its parasitic glochidia (larvae) are unknown. This study identified blue catfish [Ictaluris furcatus (Lesueur)] and confirmed channel catfish [Ictaluris punctatus (Rafinesque)] as suitable hosts. The time required for glochidia to metamorphose and for peak juvenile excystment to begin was water temperature dependent and ranged from 28 to 37 d in a constant thermal regime (19 C); totaled 70 d in a varied thermal regime (12-19 C); and ranged 260 to 262 d in simulated natural thermal regimes (0-21 C). We developed a quantitative model that describes the thermal-temporal relation and used it to empirically estimate the species-specific low-temperature threshold for development of glochidia into juveniles on channel catfish (9.26 C) and the cumulative temperature units of development required to achieve peak excystment of juveniles from blue catfish (383 C???d) and channel catfish (395 C???d). Long-term tests simulated the development of glochidia into juveniles in natural thermal regimes and consistently affirmed the validity of these estimates, as well as provided evidence for a thermal cue (17-20 C) that presumably is needed to trigger peak juvenile excystment. These findings substantiate our model and provide an approach that could be used to determine corresponding thermal criteria for early life development of other mussel species. These data can be used to improve juvenile mussel production in propagation programs designed to help recover imperiled species and may also be useful in detecting temporal climatic changes within a watershed.

  18. Mytilid mussels: global habitat engineers in coastal sediments

    NASA Astrophysics Data System (ADS)

    Buschbaum, Christian; Dittmann, Sabine; Hong, Jae-Sang; Hwang, In-Seo; Strasser, Matthias; Thiel, Martin; Valdivia, Nelson; Yoon, San-Pil; Reise, Karsten

    2009-03-01

    Dense beds of mussels of the family Mytilidae occur worldwide on soft-bottoms in cold and warm temperate coastal waters and have usually been considered hot spots of biodiversity. We examined intertidal mussel beds at four distant locations around the globe with the same sampling method, to find out whether this “hot spot” designation holds universally. We studied species assemblages within the matrices of byssally interconnected mussels engineered by Mytilus edulis in the North Sea, by mixed Perumytilus purpuratus and Mytilus chilensis at the southern Chilean coast, by Musculista senhousia in the Yellow Sea and by Xenostrobus inconstans at the coast of southern Australia. In all cases, species assemblages inside mussel beds were significantly different from those outside with many species being restricted to one habitat type. However, species richness and diversity were not generally higher in mussel beds than in ambient sediments without mussels. In the North Sea ( M. edulis) and at the Chilean coast ( P. purpuratus, M. chilensis), mussel beds have markedly higher species numbers and diversities than surrounding sediments, but this was not the case for mussel beds in Australia ( X. inconstans) and the Yellow Sea ( M. senhousia) where numbers of associated species were only slightly higher and somewhat lower than in adjacent sediments, respectively. In conclusion, although soft bottom mytilid mussels generally enhance habitat heterogeneity and species diversity at the ecosystem level, mussel beds themselves are not universal centres of biodiversity, but the effects on associated species are site specific.

  19. Processes limiting mussel bed restoration in the Wadden-Sea

    NASA Astrophysics Data System (ADS)

    de Paoli, Hélène; van de Koppel, Johan; van der Zee, Els; Kangeri, Arno; van Belzen, Jim; Holthuijsen, Sander; van den Berg, Aniek; Herman, Peter; Olff, Han; van der Heide, Tjisse

    2015-09-01

    This paper reports on experimental restoration of mussel beds in the Wadden Sea and the processes that might limit successful restoration of this foundation species (i.e. substrate, predation, hydrodynamics). The importance of substrate, predation, hydrodynamic conditions and location on mussel restoration success was studied using artificially created mussel beds. Experimental beds established on a stable substrate (coir net) were compared with control beds established on sand, at three locations in the Wadden Sea. Their persistence was followed over time. The results revealed a near disappearance of all experimental beds in just over 7 months. Providing a stable substrate did not improve mussel survival. Predation could not explain the disappearance of the beds, as the maximal predation rate by birds was found to be insufficient to have a significant effect on mussel cover. Differences in wave conditions alone could also not explain the variation in decline of mussel cover between the locations. However, the gradual disappearance of mussels from the seaward side of the bed strongly suggested that hydrodynamic conditions (i.e. combined effects of waves and current) played an important role in the poor persistence of the artificial beds. Our results highlight the fact that restoration of mussel beds in dynamic areas cannot simply be implemented by mussel transplantation, particularly if additional measures to prevent wave losses are not taken, even when artificial substrate is provided to facilitate mussel adhesion.

  20. Zebra mussel-directed foodchain transfer of environmental contaminants

    SciTech Connect

    Fisher, S.W.; Bruner, K.A.; Landrum, P.F.

    1994-12-31

    Zebra mussel densities in some near-shore areas of Lake Erie exceed 500,000 individuals m{sup 3}. Because of their large biomass, the zebra mussels can collectively filter the entire volume of Lake Erie`s western basin in approximately 7 days. In so doing, the mussels remove a significant fraction of suspended particles, including algae and sediment. If those particles are contaminated with PCBs, the mussels could potentially redirect contaminant cycling in Lake Erie. Their data show that contaminated particles are a significant source of contaminants for the zebra mussel with sediment being more significant source than algae. When particles are the source of contamination for the zebra mussel, significant foodchain contamination may result from direct consumption of contaminated mussels or via an indirect route in which unassimilated contaminants are shunted into zebra mussel feces and the latter are consumed by benthic invertebrates. Trophic transfer of PCBs from zebra mussel feces to gammarids was measured. Importantly, biomagnification of some PCB congeners occurred during foodchain transfer from particles to mussels to feces such that the indirect route of transfer through ingestion of contaminated feces is more significant ecologically. Implications for Lake Erie foodchains will be discussed.

  1. 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.

  2. NATIVE FRESHWATER FISH AND MUSSEL SPECIES RICHNESS

    EPA Science Inventory

    These data represent predicted current distributions of all native freshwater fish and freshwater mussels in the Middle-Atlantic region. The data are available for both 8-digit HUCs and EMAP hexagons and represent total species counts for each spatial unit.

  3. Unique alloys prevent zebra mussel attachment

    SciTech Connect

    Ranschaert, B.; Maxson, D.

    1995-10-01

    This article describes cooperative research and application by a utility and an intake screen manufacturer of materials that are resistive to fouling by mussels. The article describes the intake structure, the screen manufacturer`s efforts to identify resistive materials, manufacture and installation of screens using the resistive copper alloys and the results achieved.

  4. Zebra Mussel Monitoring and Control Guide

    SciTech Connect

    Not Available

    1992-12-01

    The Electric Power Research Institute (EPRI) Zebra Mussel Monitoring and Control Guide is a comprehensive compilation of US and European practices as reported in the open literature as of the end of 1992. EPRI considers the guide to be a living' document and will update it periodically in order to provide results of current research on chemical and nonchemical control technologies and utility experiences. The zebra mussel has infested all of the Great Lakes and other major rivers and waterways and is positioned to spread even more to the adjoining river basins. The impact of the zebra mussel on industrial power plantsis as a biofouler that clogs water systems and heat exchangers. This EPRI guideline identifies the zebra mussel, discusses its distribution in the United States, presents the potential threats to power plants, and presents the methods to initiate monitoring and control programs. Both preventive and corrective measures are presented. Preventive measures include various monitoring methods to initiate control techniques. The control techniques include both chemical and nonchemical together with combining techniques. Corrective methods include operational considerations, chemical cleaning, and mechanical/physical cleaning. It also may be possible to incorporate design changes, such as open to closed-loop backfit, backflushing, or pretreatment for closed systems. Various appendices are included that contain specifications to aid utilities in implementing several of the monitoring and control technologies, results of chemical evaluations at Cleveland Electric Illuminating Company plants, and data on the fate of various commercial molluscicides.

  5. Zebra mussel control using acoustic energy

    SciTech Connect

    Tiller, G.W.; Gaucher, T.A.; Menezes, J.K.; Dolat, S.W. )

    1992-01-01

    A practical and economical device or method that reduces zebra mussel colonization without detrimental side effects is highly desirable. An ideal method is one that could be installed near, on, or in existing raw water intakes and conduits. It must have a known effect that is limited to a defined area, should have maximum effects on a targeted species, and preferably have a low life cycle cost than the current alternative methods of control and maintenance. Underwater sound could be such a desirable solution, if found to be an effective control measure for zebra mussels. Although sound most often applies specifically to acoustic energy that is audible to humans, 20 Hertz (Hz) to 20 kiloHertz (kHz), in this report we will use the terms sound and acoustic to include acoustic energy between 100 Hz and 100 MegaHertz (MHz). This research on zebra mussel biofouling is designed to effect the early developmental stages in the life cycle of Dreissena polymorpha (Pallas). Vulnerable stages in the development of D. polymorpha that might yield to site-specific acoustic deterrence measures include the free-swimming larval veliger stage, the postveliger pre-attachment demersal stage, and the immediate post-attachment stage. The proposed applications include surface treatment to prevent, reduce or eliminate colonization on underwater structures, and the stream treatment to reduce or eliminate (destroy) mussel larvae entrained in a moving volume of water.

  6. 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)

  7. Control of zebra mussels with ultraviolet radiation

    SciTech Connect

    Lewis, D.P.

    1998-07-01

    This paper presents the results of research on the effects of low and medium pressure ultraviolet (UV) radiation on zebra mussel mortality carried out between 1992 and 1995. An initial 1992 study, carried out by Aquatic Sciences (ASI), showed that flow-through UV systems have the ability to kill zebra mussels and prevent them from attaching to downstream surfaces. However, this work did not include expanded testing to determine the limitations of UV radiation at higher flow rates or to further define effective working parameters. The 1994 study was carried out at the Lennox Thermal Generating Station (TGS) of Ontario Hydro in Kingston, Ontario. This study involved the testing of two open channel UV systems (medium and low pressure) in an effort to determine flow rates and volumes for which UV disinfection would be effective and practical for the prevention of zebra mussel infestation. It was recommended that medium pressure (MP) and low pressure (LP) UV systems be tested for their ability to control downstream settlement of zebra mussels, in flow-through trials.

  8. Factors influencing trematode parasite burdens in mussels (Mytilus spp) from the north Atlantic ocean across to the north Pacific

    NASA Astrophysics Data System (ADS)

    Wilson, J. G.; Galaktionov, K. V.; Sukhotin, A. A.; Skirnisson, K.; Nikolaev, K. E.; Ivanov, M. I.; Bustnes, J. O.; Saville, D. H.; Regel, K. V.

    2013-11-01

    The level and incidence of infection of blue mussels (Mytilus spp) by the trematode parasites Himasthla, Renicola and Gymnophallus were studied at 22 sites from north Atlantic waters (Ireland, Iceland, Norway) and across the Arctic Ocean to the Sea of Ohktosk in the north Pacific. Only at one site (Pechora Sea) were no parasites at all recorded. Infestation levels ranged up to 100% of individuals sampled.Data were analysed with the PRIMER-E package BEST routine. The analysis indicated a considerable influence of geographic location, with closely-connected sites also grouped together on the basis of their parasite communities. The BEST routine suggested that the major influence on infestation was bird (final host) numbers, but that exposure was also a strong factor. The implications of these findings in relation to human exploitation of mussels, to bird conservation, and to the provision of ecosystem goods and services in general is discussed.

  9. An updated molecular basis for mussel immunity.

    PubMed

    Gerdol, Marco; Venier, Paola

    2015-09-01

    Non-self recognition with the consequent tolerance or immune reaction is a crucial process to succeed as living organisms. At the same time the interactions between host species and their microbiome, including potential pathogens and parasites, significantly contribute to animal life diversity. Marine filter-feeding bivalves, mussels in particular, can survive also in heavily anthropized coastal waters despite being constantly surrounded by microorganisms. Based on the first outline of the Mytilus galloprovincialis immunome dated 2011, the continuously growing transcript data and the recent release of a draft mussel genome, we explored the available sequence data and scientific literature to reinforce our knowledge on the main gene-encoded elements of the mussel immune responses, from the pathogen recognition to its clearance. We carefully investigated molecules specialized in the sensing and targeting of potential aggressors, expected to show greater molecular diversification, and outlined, whenever relevant, the interconnected cascades of the intracellular signal transduction. Aiming to explore the diversity of extracellular, membrane-bound and intracellular pattern recognition receptors in mussel, we updated a highly complex immune system, comprising molecules which are described here in detail for the first time (e.g. NOD-like receptors) or which had only been partially characterized in bivalves (e.g. RIG-like receptors). Overall, our comparative sequence analysis supported the identification of over 70 novel full-length immunity-related transcripts in M. galloprovincialis. Nevertheless, the multiplicity of gene functions relevant to immunity, the involvement of part of them in other vital processes, and also the lack of a refined mussel genome make this work still not-exhaustive and support the development of more specific studies. PMID:25700785

  10. Establishing mussel behavior as a biomarker in ecotoxicology.

    PubMed

    Hartmann, Jason T; Beggel, Sebastian; Auerswald, Karl; Stoeckle, Bernhard C; Geist, Juergen

    2016-01-01

    Most freshwater mussel species of the Unionoida are endangered, presenting a conservation issue as they are keystone species providing essential services for aquatic ecosystems. As filter feeders with limited mobility, mussels are highly susceptible to water pollution. Despite their exposure risk, mussels are underrepresented in standard ecotoxicological methods. This study aimed to demonstrate that mussel behavioral response to a chemical stressor is a suitable biomarker for the advancement of ecotoxicology methods that aids mussel conservation. Modern software and Hall sensor technology enabled mussel filtration behavior to be monitored real-time at very high resolution. With this technology, we present our method using Anodonta anatina and record their response to de-icing salt pollution. The experiment involved an environmentally relevant 'pulse-exposure' design simulating three subsequent inflow events. Three sublethal endpoints were investigated, Filtration Activity, Transition Frequency (number of changes from opened to closed, or vice versa) and Avoidance Behavior. The mussels presented a high variation in filtration behavior, behaving asynchronously. At environmentally relevant de-icing salt exposure scenarios, A. anatina behavior patterns were significantly affected. Treated mussels' Filtration Activity decreased during periods of very high and long de-icing salt exposure (p<0.001), however, increased during short de-icing salt exposure. Treated mussels' Transition Frequency increased during periods of very high and long de-icing salt exposure (p<0.001), which mirrored the Avoidance Behavior endpoint observed only by mussels under chemical stress. Characteristics of Avoidance Behavior were tighter shell closures with repeated and irregular shell movements which was significantly different to their undisturbed resting behavior (p<0.001). Additionally, we found that mussels were sensitive to a chemical stressor even when the mussel's valves were closed. Due

  11. The Danish vaccination register.

    PubMed

    Grove Krause, T; Jakobsen, S; Haarh, M; Mølbak, K

    2012-01-01

    Immunisation information systems (IIS) are valuable tools for monitoring vaccination coverage and for estimating vaccine effectiveness and safety. Since 2009, an advanced IIS has been developed in Denmark and will be implemented during 2012–14. This IIS is based on a database existing since 2000. The reporting of all administered vaccinations including vaccinations outside the national programme will become mandatory. Citizens will get access to data about their own vaccinations and healthcare personnel will get access to information on the vaccinations of their patients. A national concept of identification, a national solution combining a personal code and a card with codes, ensures easy and secure access to the register. From the outset, the IIS will include data on childhood vaccinations administered from 1996 and onwards. All Danish citizens have a unique identifier, a so called civil registration number, which allows the linking of information on vaccinations coming from different electronic data sources. The main challenge will be to integrate the IIS with the different electronic patient record systems currently existing at general practitioner, vaccination clinic and hospital level thereby avoiding double-entry. A need has been identified for an updated international classification of vaccine products on the market. Such a classification would also be useful for the future exchange of data on immunisations from IIS between countries. PMID:22551494

  12. Mussel beds — amensalism or amelioration for intertidal fauna?

    NASA Astrophysics Data System (ADS)

    Dittmann, Sabine

    1990-09-01

    The faunal assemblages of a mussel bed ( Mytilus edulis L.) and ambient sandflat were compared to study how a bioherm of suspension feeding organisms affects benthic communities in a tidal flat. During a survey of mussel beds in the Wadden Sea at the island of Sylt (North Sea), a total of 52 macrofaunal species and 44 meiobenthic plathelminth species were detected. They occupied different microhabitats in the mussel bed. 56% of the macrofauna species were dwelling in the sediment beneath the mussels and 42% were epibenthic or epiphytic. The latter were restricted in their occurrence to the mussel bed. Along a transect from the sandflat to the mussel bed the mean species densities of macrofauna did not differ significantly, while abundances were significantly lower in the mussel bed than in the sandflat. The composition of the assemblages shifted from a dominance of Polychaeta in the sandflat to Oligochaeta in the mussel bed. Surface filter-feeding polychaetes of the sandflat ( Tharyx marioni) were displaced by deposit feeding polychaetes under the mussel cover ( Capitella capitata, Heteromastus filiformis). The total meiobenthic density was lower and single taxa (Ostracoda, Plathelminthes, Nematoda) were significantly less abundant in the mud of the mussel bed. The plathelminth assemblage was dominated by grazing species ( Archaphanostoma agile), and differed in community structure from a sandflat aseemblage. An amensalistic relationship was found between the suspension-feeding mussels and suspension-feeding infauna, while deposit-feeders were enhanced. The presence of epibenthic microhabitats results in a variety of trophic groups co-occurring in a mussel bed. This is hypothesized as trophic group amelioration and described as an attribute of heterotrophic reefs.

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

    SciTech Connect

    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.

  14. 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.

  15. The interaction between sediment, hydraulics and mussels in a river

    NASA Astrophysics Data System (ADS)

    Schwarzwälder, Kordula

    2015-04-01

    Sarah Scholtissek Technische Universität München, Hydraulic and Water Resources Engineering, München, Germany Peter Rutschmann Technische Universität München, Hydraulic and Water Resources Engineering, München, Germany Bottom structures in rivers are not only depending on the current profile, turbulence in the flow and other hydraulic conditions, but also on the biota living in the river like e.g. mussels. There is also some influence of the sediment on the biota and their decision where they settle and so on. The interaction between the current, the mussels and the sediment is actually not very well known, especially in fresh waters. Therefore experiments were cunducted in a flume in the lab in Obernach to gain more information about these interactions. The mussels used for these experiments are painters mussels (Unio Pictorum). These mussels are widely spreaded in European fresh waters, but their behaviour is also comparable to mussels which are more sensitive and therefore rare like the pearl mussel (Margaritifera Margaritifera). In the experiments 15 individuals are monitored how they move and spread in the flume. Then the hydraulic conditions and the sediment around the mussels are measured with laser scanning and PIV (particle image velocimetry). with the help of these measurement techniques it is possible to do contactless measurements even of the small eddies around and caused by the mussels which exist only for a very short time but have an enormous effect on the sediment.

  16. A sampling method for conducting relocation studies with freshwater mussels

    USGS Publications Warehouse

    Waller, D.L.; Rach, J.J.; Cope, W.G.; Luoma, J.A.

    1993-01-01

    Low recovery of transplanted mussels often prevents accurate estimates of survival. We developed a method that provided a high recovery of transplanted mussels and allowed for a reliable assessment of mortality. A 3 x 3 m polyvinyl chloride (PVC) pipe grid was secured to the sediment with iron reinforcing bars. The grid was divided into nine 1-m super(2) segments and each treatment segment, was stocked with 100 marked mussels. The recovery of mussels after six months exceeded 80% in all but one treatment group.

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

    PubMed Central

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

    2015-01-01

    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. PMID:26508080

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

    PubMed

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

    2015-01-01

    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. PMID:26508080

  19. 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.

  20. Blue-green algae

    MedlinePlus

    ... Talk with your health provider.Medications that slow blood clotting (Anticoagulant / Antiplatelet drugs)Blue-green algae might slow blood clotting. Taking blue-green algae along with medications that ...

  1. Greening the Blue Bottle.

    ERIC Educational Resources Information Center

    Wellman, Whitney E.; Noble, Mark E.

    2003-01-01

    Compares the revised Blue Bottle formulation to the classical Blue Bottle. Indicates that the revised formulation gives a somewhat bluer solution, but initially slower reduction when compared to the classical formulation. (Author/KHR)

  2. The Blue Water

    ERIC Educational Resources Information Center

    Berger, J. Joel

    1973-01-01

    Describes some of the advantages of an elementary science activity in which students discover that blowing through a straw into a bromthymol blue solution changes the color to yellow. Directions are provided for preparing the bromthymol blue solution. (JR)

  3. Blue nightshade poisoning

    MedlinePlus

    ... when someone eats parts of the blue nightshade plant. This article is for information only. DO NOT ... is found in the blue nightshade ( Solanum dulcamara ) plant, especially in the fruit and leaves.

  4. Gospel and Blues Improvisation.

    ERIC Educational Resources Information Center

    Smallwood, Richard

    1980-01-01

    The similarities and differences between blues and gospel music are identified and the author suggests that both blues and gospel music have inherent improvisational qualities. Methods of capitalizing on these qualities are presented. Selected readings and recordings are included. (KC)

  5. Blue nightshade poisoning

    MedlinePlus

    Blue nightshade poisoning occurs when someone eats parts of the blue nightshade plant. This article is for information only. DO NOT use it to treat or manage an actual poison exposure. If you or someone you ...

  6. Metabolomics analysis of shucked mussels' freshness.

    PubMed

    Aru, Violetta; Pisano, Maria Barbara; Savorani, Francesco; Engelsen, Søren Balling; Cosentino, Sofia; Cesare Marincola, Flaminia

    2016-08-15

    In this work a NMR metabolomics approach was applied to analyze changes in the metabolic profile of the bivalve mollusk Mytilus galloprovincialis upon storage at 0°C and 4°C for 10 and 6 days, respectively. The most significant microbial groups involved in spoilage of mussels were also investigated. The time-related metabolic signature of mussels was analysed by Orthogonal Partial Least Squares Discriminant Analysis (OPLS-DA) which revealed a clear discrimination between the fresh samples and those stored at 0°C and 4°C. The results evidenced a noticeable increase in acetate, lactate, succinate, alanine, branched chain amino acids, trimethylamine and a progressive decline of osmolytes like betaine, homarine and taurine during storage. Exploration of the correlations of these metabolites with microbial counts suggested their use as potential biomarkers of spoilage. The results support the use of NMR metabolomics as a valuable tool to provide information on seafood freshness. PMID:27006214

  7. Ocean acidification impacts mussel control on biomineralisation

    NASA Astrophysics Data System (ADS)

    Fitzer, Susan C.; Phoenix, Vernon R.; Cusack, Maggie; Kamenos, Nicholas A.

    2014-08-01

    Ocean acidification is altering the oceanic carbonate saturation state and threatening the survival of marine calcifying organisms. Production of their calcium carbonate exoskeletons is dependent not only on the environmental seawater carbonate chemistry but also the ability to produce biominerals through proteins. We present shell growth and structural responses by the economically important marine calcifier Mytilus edulis to ocean acidification scenarios (380, 550, 750, 1000 µatm pCO2). After six months of incubation at 750 µatm pCO2, reduced carbonic anhydrase protein activity and shell growth occurs in M. edulis. Beyond that, at 1000 µatm pCO2, biomineralisation continued but with compensated metabolism of proteins and increased calcite growth. Mussel growth occurs at a cost to the structural integrity of the shell due to structural disorientation of calcite crystals. This loss of structural integrity could impact mussel shell strength and reduce protection from predators and changing environments.

  8. 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.

  9. Rope can help with early detection of zebra mussels

    SciTech Connect

    McNabb, C.

    1993-06-01

    Many of the waters in the western US meet all the ecological requirements of suitable habitat for zebra mussels, which can spread to new bodies of water by attaching to boats. With that in mind, Reclamation has launched Zebra Mussel Watch, a program aimed at early detection of the mussel in western waters. As part of the watch program, Reclamation suggests attaching one end of a rope to a weight such as a brock, rick, or cinder block, and placing the weight in shallow water to detect the arrival of zebra mussels. Any kind of rope will do, but nylon is preferred because small mussels are easier to distinguish on nylon's smooth surface than on ropes with rough surfaces. Young mussels smaller than the head of a common straight pin are transparent when they first settle and probably will not be visible to the naked eye for several weeks, when they are larger and they take on the appearance of small, dark-colored clams. [Note: over time, algae, bacteria, and debris will cause the rope to darken. So the color of the rope used doesn't make much difference.] Hang a rope in 8 feet or less of well-oxygenated water where wave action will not move the bottom of the rope to any great degree. (Zebra mussels like slow currents and will not attach where the current is moving 4 to 5 feet per second or faster.) Leave the rope in the water two or three weeks to allow microorganisms to grow on it. Young mussels will settle on surfaces that are coated with algae and other microscopic organisms. Then, at two- to three-week intervals, lift the rope and examine it for young mussels. If adults are around, the young eventually will show up. Reclamation believes that by detecting the first arrival of the mussels, it can implement plans to control the spread of the mussels and alert nearby projects to the approaching menace.

  10. 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.

  11. Fluoranthene transport in mussel blood plasma

    SciTech Connect

    Lazinsky, D.; Robinson, W.E.

    1995-12-31

    The role of mussel (Mytilus edulis) blood plasma in fluoranthene transport was investigated using in vitro binding studies and invivo exposure studies. In vitro binding studies on fluoranthene-spiked plasma utilized dialysis, ultrafiltration and fluorescence quenching. A significant degree of fluoranthene binding was observed with all the methods; as much 99.7% of the fluoranthene was bound to plasma proteins. Conditional affinity constants (log K{sub a}), calculated using a single component complexation model, averaged 6.8 M{sup {minus}1} suggesting a moderate affinity interaction between fluoranthene and plasma proteins. Mussels were exposed in vivo to {sup 3}H-fluoranthene and blood and tissues were sampled at 0.5, 3.5, 7, 24, 72 h post exposure. The mussels removed an average of 90% of the fluoranthene from the seawater within the first 0.5 h of exposure. Body tissues rapidly accumulated fluoranthene. Approximately 50% of the absorbed dose was present in the tissues by 0.5 h and this increased to 96% by 3.5 h of exposure. Within the blood, fluoranthene was mainly partitioned in the plasma. Plasma fluoranthene decreased to 50% within 3.5 h. The fluoranthene distribution remained relatively constant throughout the remainder of the 72 h exposure. Ultrafiltration of plasma exposed in vivo indicated that fluoranthene was not free, but bound to plasma proteins. The plasma protein concentrations fluctuated during exposure, but were virtually the same at 0.5 h and 72 h post exposure.

  12. Zebra mussel control with backwash filtration

    SciTech Connect

    Dardeau, E.A. Jr.; Bivens, T.

    1995-12-31

    Zebra Mussels (Dreissena polymorpha) were found in North American waters in 1988 at Lake St. Clair, Michigan, when a ship from a European freshwater port released its ballast water. These organisms quickly spread from the Great Lakes to many midwestern, eastern, and southern streams and lakes. As macrofoulers, they quickly colonize new areas on many natural and artificial substrates. Zebra mussels clog intakes, piping, and screens. Power production facilities that withdraw large quantities of raw water to generate electricity and cool critical components are especially vulnerable. Many control strategies have been proposed and tested; however, not all of them are environmentally acceptable. The US Army Corps of Engineers, under the auspices of the Nonindigenous Aquatic Nuisance Prevention and Control Act of 1990, has initiated a research program to control zebra mussels at public facilities. One test being conducted under this research program is a cooperative effort between the Corps` Nashville District, the Corps` Waterways Experiment Station, and several other agencies. The test involves the design and test of a backwash filtration system for a hydropower project in the Cumberland River Basin. The preliminary design, based on lessons learned from associated tests, is discussed. In addition, recommendations for future use are presented.

  13. Relationships between community structure of freshwater mussels and host fishes in a central Ohio watershed

    Technology Transfer Automated Retrieval System (TEKTRAN)

    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 ...

  14. Effects of ammonia on freshwater mussels in the St. Croix River

    USGS Publications Warehouse

    Newton, Teresa J.

    2004-01-01

    The St. Croix River contains a diverse and abundant group of freshwater mussels. The St. Croix is one of the few rivers in the Midwest not substantially affected by the invasion of the exotic zebra mussel, which encrusts and kills native freshwater mussels. Increased concentrations of ammonia in river sediments, however, poses a significant threat to mussels.

  15. 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…

  16. Reducing costly zebra mussel infestations at power plants

    SciTech Connect

    Smythe, G.

    1994-10-01

    The fast-spreading-zebra mussel has significant potential to foul intakes and other water systems at North American hydro projects. Chemical controls can be effective in reducing infestations, but most have environmental and other drawbacks. Several non-chemical methods promise to help project operators reduce problems associated with the mussels.

  17. In situ assessment of genotoxicity using caged freshwater mussels

    SciTech Connect

    Black, M.C.; Westerfield, S.M.

    1995-12-31

    In recent years a decline in mussel populations has been documented in many areas, particularly in contaminated environments. Mussels are particularly vulnerable to exposure to xenobiotics in sediment and/or water because of their modes of feeding and respiration and close association with sediments. Because of this potential for exposure, their apparent sensitivity to xenobiotics, and their ease in collection and handling, mussels are an excellent species for in situ biomonitoring. Recently the authors have adapted an electrophoretic assay for detecting DNA strand breakage in freshwater mussels. Using this assay DNA damage was quantified in selected tissues in two mussel species, Quadrula quadrula and Anodonta grandis, following subchronic laboratory exposures to lead and benzo[a]pyrene. Current experiments involve exposing mussels in situ in polyethylene cages and exposure racks in several environments containing genotoxic agents, including a fly ash settling pond and a site contaminated with mercury. Mussels will be exposed for 1 week to 3 months and sampled at 2 to 4week intervals. Upon removal mussels will be dissected, and mantle, adductor muscle, and foot tissue will be analyzed for DNA strand breakage and xenobiotic residues. These data will be compared with laboratory exposures to single compounds conducted over the same exposure durations.

  18. Subjectless Sentences in Child Danish.

    ERIC Educational Resources Information Center

    Hamann, Cornelia; Plunkett, Kim

    1998-01-01

    Examined data for two Danish children to determine subject omission, verb usage, and sentence subjects. Found that children exhibit asymmetry in subject omission according to verb type as subjects are omitted from main verb utterances more frequently than from copula utterances. Concluded that treatment of child subject omission should involve…

  19. Nature and Nationhood: Danish Perspectives

    ERIC Educational Resources Information Center

    Schnack, Karsten

    2009-01-01

    In this paper, I shall discuss Danish perspectives on nature, showing the interdependence of conceptions of "nature" and "nationhood" in the formations of a particular cultural community. Nature, thus construed, is never innocent of culture and cannot therefore simply be "restored" to some pristine, pre-lapsarian state. On the other hand,…

  20. Spatial and temporal trends of contaminants in mussel sampled around the Icelandic coastline.

    PubMed

    Sturludottir, Erla; Gunnlaugsdottir, Helga; Jorundsdottir, Hronn O; Magnusdottir, Elin V; Olafsdottir, Kristin; Stefansson, Gunnar

    2013-06-01

    Contaminants have been determined in blue mussels (Mytilus edulis) at 11 locations around the Icelandic coastline from 1990 to 2010. The aim of the present study was to investigate if there has been a change in concentration of contaminants around the Icelandic coastline for the last two decades and if the concentrations and changes, if present, were consistent between locations. Concentrations of the persistent organic pollutants, p,p'-dichlorodiphenyldichloroethene (p,p'-DDE), hexachlorobenzene (HCB), α-hexachlorocyclohexane (α-HCH), polychlorinated biphenyl (PCB-153) and trans-nonachlor, have decreased at most of the sampling locations in Iceland in recent years. However, an increasing trend was found at a few locations that could be explained by anthropogenic activity. The concentration levels of the persistent organics were much lower than found at the Norwegian, USA and Chinese coasts, especially levels of p,p'-DDE. The concentration of copper and selenium had a consistent pattern of change and concentration between locations over the period which showed a decreasing trend in recent years. The trace elements arsenic, cadmium, mercury and zinc showed more variation in concentration between locations, the concentration of arsenic, mercury and zinc was fairly stable over the period, whereas there were fluctuations in cadmium concentrations. The concentrations of cadmium and zinc were observed to be somewhat higher than found in mussels from Norway, USA and China but values of mercury and lead were much lower in the mussel sampled in Iceland. The higher concentrations of cadmium and zinc can be explained by the volcanic activity in Iceland but no major anthropogenic sources of trace elements are known in Iceland. PMID:23567170

  1. IMPACT OF WATER PH ON ZEBRA MUSSEL MORTALITY

    SciTech Connect

    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. 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.

  2. Cumberlandian Mollusk Conservation Program. Activity 1: mussel distribution surveys

    SciTech Connect

    Ahlstedt, S.A.

    1986-01-01

    The distribution of Cumberlandian mollusks in the Tennessee Valley is one of nine research activities developed as part of TVA's Cumberlandian Mollusk Conservation Program (CMCP). The name Cumberlandian refers to an endemic faunal assemblage that encompasses portions of 7 states bordering the southern Appalachian Mountains and the Cumberland Plateau Region. This geographic region is known as one of the major centers for mussel speciation and is considered the most prolific areas of the world for this particular group of organisms. Nine Tennessee Valley streams were selected for intensive qualitative and quantitative mussel surveys under Activity I of the CMCP. The surveys were designed to gather information on the present distribution of Cumberlandian mollusks. The streams chosen for surveys were based on the documented presence of diverse mussel fauna, endangered mussels, and/or sufficient information (diverse fish fauna, good water quality, etc.) to suggest potential for occurrence of diverse mussel fauna or endangered species.

  3. 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.

  4. California sea mussel and bay mussel: Species profiles: Life histories and environmental requirements of coastal fishes and invertebrates (Pacific Southwest)

    SciTech Connect

    Shaw, W.N.; Hassler, T.J.; Moran, D.P.

    1988-09-01

    Species profiles are literature summaries of the taxonomy, morphology, distribution, life history, and environmental requirements of coastal aquatic species. They are prepared to assist in environmental impact assessment. The California sea mussel, Mytilus californianus, and the bay mussel, M. edulis, are commonly collected for bait. Some commercial landing and aquaculture occurs at a very low level of production. Both species are distributed along the California coast; the sea mussel is more commonly found on intertidal coastal rocks and the bay mussel on pilings and other hard substrates in bays and estuaries. The eggs of both species develop into a trochophore stage in 12--24 hours after fertilization, and the planktonic larval stage lasts 3--4 weeks. Sexual maturity can occur in one year. Spawning of the sea mussel occurs sporadically throughout the year; the bay mussel spawns in central California in late fall and winter. Maximum length is 120--150 mm for the bay mussel and 200--250 mm for the sea mussel. Both species are regarded as unsafe to eat from May 1 to October 31 due to the possible presence of paralytic shellfish poisoning. 55 refs., 4 figs., 5 tabs.

  5. 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. PMID:27233049

  6. Microplastics are taken up by mussels (Mytilus edulis) and lugworms (Arenicola marina) living in natural habitats.

    PubMed

    Van Cauwenberghe, Lisbeth; Claessens, Michiel; Vandegehuchte, Michiel B; Janssen, Colin R

    2015-04-01

    We studied the uptake of microplastics under field conditions. At six locations along the French-Belgian-Dutch coastline we collected two species of marine invertebrates representing different feeding strategies: the blue mussel Mytilus edulis (filter feeder) and the lugworm Arenicola marina (deposit feeder). Additional laboratory experiments were performed to assess possible (adverse) effects of ingestion and translocation of microplastics on the energy metabolism (cellular energy allocation) of these species. Microplastics were present in all organisms collected in the field: on average 0.2 ± 0.3 microplastics g(-1) (M. edulis) and 1.2 ± 2.8 particles g(-1) (A. marina). In a proof of principle laboratory experiment, mussels and lugworms exposed to high concentrations of polystyrene microspheres (110 particles mL(-1) seawater and 110 particles g(-1) sediment, respectively) showed no significant adverse effect on the organisms' overall energy budget. The results are discussed in the context of possible risks as a result of the possible transfer of adsorbed contaminants. PMID:25617854

  7. Maintained larval growth in mussel larvae exposed to acidified under-saturated seawater

    PubMed Central

    Ventura, Alexander; Schulz, Sabrina; Dupont, Sam

    2016-01-01

    Ocean acidification (OA) is known to affect bivalve early life-stages. We tested responses of blue mussel larvae to a wide range of pH in order to identify their tolerance threshold. Our results confirmed that decreasing seawater pH and decreasing saturation state increases larval mortality rate and the percentage of abnormally developing larvae. Virtually no larvae reared at average pHT 7.16 were able to feed or reach the D-shell stage and their development appeared to be arrested at the trochophore stage. However larvae were capable of reaching the D-shell stage under milder acidification (pHT ≈ 7.35, 7.6, 7.85) including in under-saturated seawater with Ωa as low as 0.54 ± 0.01 (mean ± s. e. m.), with a tipping point for normal development identified at pHT 7.765. Additionally growth rate of normally developing larvae was not affected by lower pHT despite potential increased energy costs associated with compensatory calcification in response to increased shell dissolution. Overall, our results on OA impacts on mussel larvae suggest an average pHT of 7.16 is beyond their physiological tolerance threshold and indicate a shift in energy allocation towards growth in some individuals revealing potential OA resilience. PMID:27020613

  8. Maintained larval growth in mussel larvae exposed to acidified under-saturated seawater.

    PubMed

    Ventura, Alexander; Schulz, Sabrina; Dupont, Sam

    2016-01-01

    Ocean acidification (OA) is known to affect bivalve early life-stages. We tested responses of blue mussel larvae to a wide range of pH in order to identify their tolerance threshold. Our results confirmed that decreasing seawater pH and decreasing saturation state increases larval mortality rate and the percentage of abnormally developing larvae. Virtually no larvae reared at average pHT 7.16 were able to feed or reach the D-shell stage and their development appeared to be arrested at the trochophore stage. However larvae were capable of reaching the D-shell stage under milder acidification (pHT ≈ 7.35, 7.6, 7.85) including in under-saturated seawater with Ωa as low as 0.54 ± 0.01 (mean ± s. e. m.), with a tipping point for normal development identified at pHT 7.765. Additionally growth rate of normally developing larvae was not affected by lower pHT despite potential increased energy costs associated with compensatory calcification in response to increased shell dissolution. Overall, our results on OA impacts on mussel larvae suggest an average pHT of 7.16 is beyond their physiological tolerance threshold and indicate a shift in energy allocation towards growth in some individuals revealing potential OA resilience. PMID:27020613

  9. Radioprotection against DNA damage by an extract of Indian green mussel, Perna viridis (L).

    PubMed

    Kumaran, Sreekumar P; Kutty, Binoj C; Chatterji, Anil; Subrayan, Parameswaran P; Mishra, Kaushala Prasad

    2007-01-01

    This study describes the radioprotective ability of a hydrolysate prepared using an enzyme-acid hydrolysis method from the green mussel Perna viridis in terms of its ability to prevent radiation-induced damage in plasmid DNA, cell death, reactive oxygen species (ROS) formation, and DNA damage in mice lymphocytes. The mussel hydrolysate (MH) present during irradiation showed significant protection from gamma-radiation-induced strand breaks in plasmid DNA as evaluated by gel electrophoresis. Viability studies by trypan blue dye exclusion and MTT assay showed that preincubation of mice splenic lymphocytes with MH protected them from gamma-radiation-mediated killing. Moreover, the presence of MH during irradiation of isolated mice lymphocytes significantly decreased the DNA damage, as measured by comet assay. Measurement of intracellular ROS by dichlorofluorescein fluorescence revealed that the presence of MH effectively reduced the ROS generated in lymphocytes by both chemical method and gamma-irradiation. Prevention of DNA damage both in plasmid and lymphocytes and cell death in lymphocytes appears correlated with reduction of oxidatively generated free radicals. It is concluded that protection against radiation-induced cell death and DNA damage by MH was attributable to reduction of reactive free radical species generated by gamma-radiation. PMID:18197824

  10. 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

  11. 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. PMID:16599964

  12. 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.

  13. Restoration of oiled mussel beds in Prince William Sound, Alaska.

    PubMed

    Carls, Mark G; Harris, Patricia M; Rice, S D

    2004-06-01

    Natural loss of hydrocarbons was often low from mussel (Mytilus trossulus) beds (which were typically not cleaned after the Exxon Valdez oil spill), thus this habitat remained a long-term source of oil. Consequently, experimental restoration of nine contaminated beds was attempted in 1994; mussels were removed, contaminated surface sediment was replaced (33 metric tons), and original mussels were returned. Hydrocarbon concentrations and mussel populations were monitored for 5 years thereafter. Post-restoration mussel population fluctuations were indistinguishable from regional changes. Increased short-term oil loss was apparent, but long-term (5 year) improvement was equivocal and difficult to distinguish from natural losses. By 1999, oil concentrations in mussels were typically at baseline levels in restored and oiled reference beds; concentrations in replaced sediment were elevated in one third of restored beds, indicating recontamination from underlying or surrounding sediment. Our results suggest mussel relocation is feasible but suggest oil might more effectively be removed from sediment mechanically or chemically than manually. PMID:14967519

  14. 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.

  15. Copper and copper-nickel alloys as zebra mussel antifoulants

    SciTech Connect

    Dormon, J.M.; Cottrell, C.M.; Allen, D.G.; Ackerman, J.D.; Spelt, J.K.

    1996-04-01

    Copper has been used in the marine environment for decades as cladding on ships and pipes to prevent biofouling by marine mussels (Mytilus edulis L.). This motivated the present investigation into the possibility of using copper to prevent biofouling in freshwater by both zebra mussels and quagga mussels (Dreissena polymorpha and D. bugensis collectively referred to as zebra mussels). Copper and copper alloy sheet proved to be highly effective in preventing biofouling by zebra mussels over a three-year period. Further studies were conducted with copper and copper-nickel mesh (lattice of expanded metal) and screen (woven wire with a smaller hole size), which reduced the amount of copper used. Copper screen was also found to be strongly biofouling-resistant with respect to zebra mussels, while copper mesh reduced zebra mussel biofouling in comparison to controls, but did not prevent it entirely. Preliminary investigations into the mechanism of copper antifouling, using galvanic couples, indicated that the release of copper ions from the surface of the exposed metal into the surrounding water is directly or indirectly responsible for the biofouling resistance of copper.

  16. 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.

  17. 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.

  18. Templated blue phases.

    PubMed

    Ravnik, Miha; Fukuda, Jun-ichi

    2015-11-21

    Cholesteric blue phases of a chiral liquid crystal are interesting examples of self-organised three-dimensional nanostructures formed by soft matter. Recently it was demonstrated that a polymer matrix introduced by photopolymerization inside a bulk blue phase not only stabilises the host blue phase significantly, but also serves as a template for blue phase ordering. We show with numerical modelling that the transfer of the orientational order of the blue phase to the surfaces of the polymer matrix, together with the resulting surface anchoring, can account for the templating behaviour of the polymer matrix inducing the blue phase ordering of an achiral nematic liquid crystal. Furthermore, tailoring the anchoring conditions of the polymer matrix surfaces can bring about orientational ordering different from those of bulk blue phases, including an intertwined complex of the polymer matrix and topological line defects of orientational order. Optical Kerr response of templated blue phases is explored, finding large Kerr constants in the range of K = 2-10 × 10(-9) m V(-2) and notable dependence on the surface anchoring strength. More generally, the presented numerical approach is aimed to clarify the role and actions of templating polymer matrices in complex chiral nematic fluids, and further to help design novel template-based materials from chiral liquid crystals. PMID:26412643

  19. Blue Willow Story Plates

    ERIC Educational Resources Information Center

    Fontes, Kris

    2009-01-01

    In the December 1997 issue of "SchoolArts" is a lesson titled "Blue Willow Story Plates" by Susan Striker. In this article, the author shares how she used this lesson with her middle-school students many times over the years. Here, she describes a Blue Willow plate painting project that her students made.

  20. Introducing the Blues.

    ERIC Educational Resources Information Center

    Sinclair, Bryan

    2000-01-01

    Discusses the history of the blues and presents a list of resources that are designed to introduce the blues, both as a feeling and as an influential part of American music and culture. Includes picture books and nonfiction for young readers, nonfiction for older readers, Web sites, and compact disks. (LRW)

  1. Comparison of organic contaminant accumulation by semipermeable membrane devices (SPMDs) and the caged mussel species Mytilus edulis

    SciTech Connect

    Hofelt, C.; Shea, D.

    1995-12-31

    The accumulation of anthropogenic contaminants by sentinel species such as the blue mussel, Mytilus edulis, is common in many monitoring programs such as the National Status and Trends Mussel Watch Program. Bivalves are used because they are filter-feeding organisms with a high lipid content and therefore accumulate pollutants readily, and they do not appear to metabolize contaminants to a large extent. There are difficulties associated with this approach however, such as mortality, changing lipid mass and respiration rates, and interspecies differences; therefore the use of a non-living substrate may be more practical. The semipermeable membrane device (SPMD) consists of a length of thin-walled polyethylene tubing with a film of high molecular weight neutral lipid (triolein) sealed inside. The SPMD, when suspended in the water column, will concentrate lipophilic organic contaminants from the surrounding environment. The authors deployed SPMDs and caged Mytilus edulis side-by-side at five sites near New Bedford Harbor, MA; an area highly contaminated with polychlorinated biphenyls (PCBs). A good correlation was observed between the SPMDs and the caged blue mussels, with R{sup 2} ranging from 0.57 to 0.85 (N = 16) for chlorinated pesticides and from 0.81 to 0.96 (N = 20) for PCBs. Bioconcentration factors (BCF) based on water column concentrations were also calculated and a good correlation was obtained between the SPMD BCFs and corresponding octanol-water partition coefficients. Unlike previous investigations, the authors found good agreement even with the highest chlorinated PCBs suggesting that there was no steric hindrance of uptake through the SPMD membrane.

  2. IMPACT OF WATER TEMPERATURE ON ZEBRA MUSSEL MORTALITY

    SciTech Connect

    Daniel P. Molloy

    2002-08-07

    These tests conducted this past quarter have indicated that the bacterium Pseudomonas fluorescens strain CL0145A is effective at killing zebra mussels at water temperatures ranging from 7 to 23 C. Percent kill will likely be somewhat lower at very low temperatures, e.g., 7 C, but even at such low temperatures high mussel kill can still be achieved (>70% kill). This is significant because the development of a zebra mussel control method that is efficacious in such a wide range of temperatures broadens its usefulness as a potential commercial product.

  3. Effects of Fucus vesiculosus covering intertidal mussel beds in the Wadden Sea

    NASA Astrophysics Data System (ADS)

    Albrecht, A.; Reise, K.

    1994-06-01

    The brown alga Fucus vesiculosus forma mytili (Nienburg) Nienhuis covered about 70% of mussel bed ( Mytilus edulis) surface area in the lower intertidal zone of Königshafen, a sheltered sandy bay near the island of Sylt in the North Sea. Mean biomass in dense patches was 584 g ash-free dry weight m-2 in summer. On experimental mussel beds, fucoid cover enhanced mud accumulation and decreased mussel density. The position of mussels underneath algal canopy was mainly endobenthic (87% of mussels with >1/3 of shell sunk into mud). In the absence of fucoids, mussels generated epibenthic garlands (81% of mussels with <1/3 of shell buried in mud). Mussel density underneath fucoid cover was 40 to 73% of mussel density without algae. On natural beds, barnacles (Balanidae), periwinkles ( Littorina littorea) and crabs (particularly juveniles of Carcinus maenas) were significantly less abundant in the presence of fucoids, presumably because most of the mussels were covered with sediment, whereas in the absence of fucoids, epibenthic mussel clumps provided substratum as well as interstitial hiding places. The endobenthic macrofauna showed little difference between covered and uncovered mussel beds. On the other hand, grazing herbivores — the flat periwinkle Littorina mariae, the isopod Jaera albifrons and the amphipods Gammarus spp. — were more abundant at equivalent sites with fucoid cover. The patchy growth of Fucus vesiculosus on mussel beds in the intertidal Wadden Sea affects mussels and their epibionts negatively, but supports various herbivores and increases overall benthic diversity.

  4. 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.

  5. Blue ocean strategy.

    PubMed

    Kim, W Chan; Mauborgne, Renée

    2004-10-01

    Despite a long-term decline in the circus industry, Cirque du Soleil profitably increased revenue 22-fold over the last ten years by reinventing the circus. Rather than competing within the confines of the existing industry or trying to steal customers from rivals, Cirque developed uncontested market space that made the competition irrelevant. Cirque created what the authors call a blue ocean, a previously unknown market space. In blue oceans, demand is created rather than fought over. There is ample opportunity for growth that is both profitable and rapid. In red oceans--that is, in all the industries already existing--companies compete by grabbing for a greater share of limited demand. As the market space gets more crowded, prospects for profits and growth decline. Products turn into commodities, and increasing competition turns the water bloody. There are two ways to create blue oceans. One is to launch completely new industries, as eBay did with online auctions. But it's much more common for a blue ocean to be created from within a red ocean when a company expands the boundaries of an existing industry. In studying more than 150 blue ocean creations in over 30 industries, the authors observed that the traditional units of strategic analysis--company and industry--are of limited use in explaining how and why blue oceans are created. The most appropriate unit of analysis is the strategic move, the set of managerial actions and decisions involved in making a major market-creating business offering. Creating blue oceans builds brands. So powerful is blue ocean strategy, in fact, that a blue ocean strategic move can create brand equity that lasts for decades. PMID:15559577

  6. Status of fresh water mussel research in Virginia

    SciTech Connect

    Neves, R.J.

    1983-10-01

    In addition to the previously described mussel research projects in Virginia, the Tennessee Valley Authority (TVA) has undertaken a wide-ranging Cumberlandian Mollusc Conservation Program to (a) accumulate information on the present distribution, life histories, and ecological requirements of the Cumberlandian mussel fauna and (b) conserve or increase populations of these species in the Tennessee River drainage. This TVA program has contributed greatly toward a better understanding of species status, water quality problems, and research needs for this unique faunal group. The attention currently being given to fresh water mussels in the upper Tennessee River system is unprecedented, and participating State and Federal agencies are to be commended for supporting conservation activities far beyond what is legally required. The success of a mollusk conservation effort will depend on public awareness, not of mussels in and for themselves but as indicators of riverine degradation and its effect on environmental health and recreational opportunities for man.

  7. Mussels as a model system for integrative ecomechanics.

    PubMed

    Carrington, Emily; Waite, J Herbert; Sarà, Gianluca; Sebens, Kenneth P

    2015-01-01

    Mussels form dense aggregations that dominate temperate rocky shores, and they are key aquaculture species worldwide. Coastal environments are dynamic across a broad range of spatial and temporal scales, and their changing abiotic conditions affect mussel populations in a variety of ways, including altering their investments in structures, physiological processes, growth, and reproduction. Here, we describe four categories of ecomechanical models (biochemical, mechanical, energetic, and population) that we have developed to describe specific aspects of mussel biology, ranging from byssal attachment to energetics, population growth, and fitness. This review highlights how recent advances in these mechanistic models now allow us to link them together across molecular, material, organismal, and population scales of organization. This integrated ecomechanical approach provides explicit and sometimes novel predictions about how natural and farmed mussel populations will fare in changing climatic conditions. PMID:25195867

  8. Impact tolerance in mussel thread networks by heterogeneous material distribution

    NASA Astrophysics Data System (ADS)

    Qin, Zhao; Buehler, Markus J.

    2013-07-01

    The Mytilidae, generally known as marine mussels, are known to attach to most substrates including stone, wood, concrete and iron by using a network of byssus threads. Mussels are subjected to severe mechanical impacts caused by waves. However, how the network of byssus threads keeps the mussel attached in this challenging mechanical environment is puzzling, as the dynamical forces far exceed the measured strength of byssus threads and their attachment to the environment. Here we combine experiment and simulation, and show that the heterogeneous material distribution in byssus threads has a critical role in decreasing the effect of impact loading. We find that a combination of stiff and soft materials at an 80:20 ratio enables mussels to rapidly and effectively dissipate impact energy. Notably, this facilitates a significantly enhanced strength under dynamical loading over 900% that of the strength under static loading.

  9. Impact tolerance in mussel thread networks by heterogeneous material distribution.

    PubMed

    Qin, Zhao; Buehler, Markus J

    2013-01-01

    The Mytilidae, generally known as marine mussels, are known to attach to most substrates including stone, wood, concrete and iron by using a network of byssus threads. Mussels are subjected to severe mechanical impacts caused by waves. However, how the network of byssus threads keeps the mussel attached in this challenging mechanical environment is puzzling, as the dynamical forces far exceed the measured strength of byssus threads and their attachment to the environment. Here we combine experiment and simulation, and show that the heterogeneous material distribution in byssus threads has a critical role in decreasing the effect of impact loading. We find that a combination of stiff and soft materials at an 80:20 ratio enables mussels to rapidly and effectively dissipate impact energy. Notably, this facilitates a significantly enhanced strength under dynamical loading over 900% that of the strength under static loading. PMID:23880603

  10. Mussels as a Model System for Integrative Ecomechanics

    NASA Astrophysics Data System (ADS)

    Carrington, Emily; Waite, J. Herbert; Sarà, Gianluca; Sebens, Kenneth P.

    2015-01-01

    Mussels form dense aggregations that dominate temperate rocky shores, and they are key aquaculture species worldwide. Coastal environments are dynamic across a broad range of spatial and temporal scales, and their changing abiotic conditions affect mussel populations in a variety of ways, including altering their investments in structures, physiological processes, growth, and reproduction. Here, we describe four categories of ecomechanical models (biochemical, mechanical, energetic, and population) that we have developed to describe specific aspects of mussel biology, ranging from byssal attachment to energetics, population growth, and fitness. This review highlights how recent advances in these mechanistic models now allow us to link them together across molecular, material, organismal, and population scales of organization. This integrated ecomechanical approach provides explicit and sometimes novel predictions about how natural and farmed mussel populations will fare in changing climatic conditions.

  11. Mussel-inspired dendritic polymers as universal multifunctional coatings.

    PubMed

    Wei, Qiang; Achazi, Katharina; Liebe, Hendrik; Schulz, Andrea; Noeske, Paul-Ludwig Michael; Grunwald, Ingo; Haag, Rainer

    2014-10-20

    A rapid and universal approach for multifunctional material coatings was developed based on a mussel-inspired dendritic polymer. This new kind of polymer mimics not only the functional groups of mussel foot proteins (mfps) but also their molecular weight and molecular structure. The large number of catechol and amine groups set the basis for heteromultivalent anchoring and crosslinking. The molecular weight reaches 10 kDa, which is similar to the most adhesive mussel foot protein mfp-5. Also, the dendritic structure exposes its functional groups on the surface like the folded proteins. As a result, a very stable coating can be prepared on virtually any type of material surface within 10 min by a simple dip-coating method, which is as fast as the formation of mussel byssal threads in nature. PMID:25200129

  12. 78 FR 5481 - Quagga Mussel Strategic Planning Meeting

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-01-25

    ... for working beyond FY13. Priorities for minimizing the spread of these mussels will be discussed. The..., February 20, 2013. ADDRESSES: The meeting will take place at the Utah Division of Wildlife, 1594 W...

  13. 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

  14. 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.

  15. The effect of sodium chlorite solutions on zebra mussel mortality

    SciTech Connect

    Dion, J.; Richer, Y.; Messer, R.

    1995-06-01

    The effect of four dilutions, 8 ppm, 40 ppm, 120 ppm and 473 ppm of the stock solution of a first product, Z-8, on zebra mussel mortality was investigated in static continuous exposure systems and compared to controls. The entire size class spectrum of the mussel population present at the sampling site was tested by leaving mussels attached to their original rock substrata. Two size class grouping of mussels, 13 mm and less and more than 13 mm in length, were exposed in the same test chambers but were analyzed separately. No mortality occurred in the controls. Concentration 8 ppm had no effect after 166 hours on both size class groupings. Concentrations 40, 120 and 473 ppm had observable killing effect within the 331 hours of experiment for both size groupings. The smaller mussels died faster than the larger ones. Another product, Z-11, was similarly tested during fall 1994 with dilutions 8, 40, 80 and 120 ppm. At 8 ppm dilution, Z-11 had induced only little mortality on both size class groupings after 739 hours. At 40, 80 and 120 ppm dilutions, Z-11 had interesting killing effect for both mussel size groupings within the 739 hours of experiment considering the somehow intermittent treatment used. The results already appear to show that sodium chlorite solutions have the potential for eventually becoming a surrogate to the use of chlorine for the control of zebra mussels. That is because they already show a good killing efficiency without being involved in the formation of undesired by-products such as the use of chlorine is. On this purpose, the product is engaged in the process of homologation by Agriculture Canada for it use as treatment against zebra mussels.

  16. Effect of diet quality on mussel biomarker responses to pollutants.

    PubMed

    González-Fernández, Carmen; Lacroix, Camille; Paul-Pont, Ika; Le Grand, Fabienne; Albentosa, Marina; Bellas, Juan; Viñas, Lucía; Campillo, Juan A; Hegaret, Helene; Soudant, Philippe

    2016-08-01

    The effect of the quality of two microalgal species on select biological and biochemical responses used as indicators of pollution were assessed. Mussels were conditioned for 6 weeks with the diatom Chaetoceros neogracile and the dinoflagellate Heterocapsa triquetra, chosen for being two clearly different types of primary production quality that differ in both biometric and biochemical characteristics. After dietary conditioning, the mussels were exposed to a polycyclic aromatic hydrocarbon, fluoranthene (FLU), for 1 week followed by 1 week of depuration. Results showed higher FLU accumulation in mussels fed on C. neogracile compared to those fed on H. triquetra. Concomitantly, a greater impact of this toxicant was observed in the biomarker responses of mussels fed on C. neogracile. These mussels showed an increase in the percentage of dead hemocytes, an activation of phagocytosis and ROS production of hemocytes after exposure. Some enzymatic activities also increased upon FLU exposure (superoxide dismutase -SOD-, catalase -CAT-, and glutathione reductases -GR-) and after depuration (glutathione-s-transferase -GST-). Results suggest that FLU exposure as well as food quality influence biomarker responses, with higher values of SOD, CAT and GR in non-exposed mussels fed on C. neogracile. In addition, upon exposure to the same FLU concentration, GR response varied according to dietary conditioning, suggesting that diet could act as a confounding factor in biomarker responses to pollution. Consequently, trophic conditions should be considered in marine pollution monitoring programs for a better interpretation of biomarker responses. PMID:27300503

  17. How does tidal flow affect pattern formation in mussel beds?

    PubMed

    Sherratt, Jonathan A; Mackenzie, Julia J

    2016-10-01

    In the Wadden Sea, mussel beds self-organise into spatial patterns consisting of bands parallel to the shore. A leading explanation for this phenomenon is that mussel aggregation reduces losses from dislodgement and predation, because of the adherence of mussels to one another. Previous mathematical modelling has shown that this can lead to spatial patterning when it is coupled to the advection from the open sea of algae-the main food source for mussels in the Wadden Sea. A complicating factor in this process is that the advection of algae will actually oscillate with the tidal flow. This has been excluded from previous modelling studies, and the present paper concerns the implications of this oscillation for pattern formation. The authors initially consider piecewise constant ("square-tooth") oscillations in advection, which enables analytical investigation of the conditions for pattern formation. They then build on this to study the more realistic case of sinusoidal oscillations. Their analysis shows that future research on the details of pattern formation in mussel beds will require an in-depth understanding of how the tides affect long-range inhibition among mussels. PMID:27343625

  18. Occurence of the Quagga Mussel Dreissena bugensis and the Zebra Mussel Dreissena polymorha in the Upper Mississippi River System

    EPA Science Inventory

    This manuscript reports on a range expansion of the invasive quagga mussel in the Great Rivers of the Upper Missippi River Basin. This research will be of interest to great river ecologists and to invasive species specialists.

  19. Successful School Principalship in Danish Schools

    ERIC Educational Resources Information Center

    Moos, Lejf; Krejsler, John; Kofod, Klaus Kasper; Jensen, Bent Brandt

    2005-01-01

    Purpose: Aims at conceptualizing and investigating the meaning of good school principalship within the space for manoeuvring that is available within the context of Danish comprehensive schools. The paper aims to present findings from case studies of two Danish schools within the frame of reference. Design/methodology/approach: Outlines the…

  20. Mongolian blue spots

    MedlinePlus

    ... bruises. This can raise a question about possible child abuse. It is important to recognize that Mongolian blue ... Elsevier Saunders; 2011:chap 11. Read More Benign Child abuse - physical Rashes Update Date 4/14/2015 Updated ...

  1. Blue Ribbon Panel Report

    Cancer.gov

    An NCI Cancer Currents blog by the NCI acting director thanking the cancer community for contributing to the Cancer Moonshot Blue Ribbon Panel report, which was presented to the National Cancer Advisory Board on September 7.

  2. Methylene blue unresponsive methemoglobinemia

    PubMed Central

    Patnaik, Sibabratta; Natarajan, Manivachagan Muthappa; James, Ebor Jacob; Ebenezer, Kala

    2014-01-01

    Acquired methemoglobinemia is an uncommon blood disorder induced by exposure to certain oxidizing agents and drugs. Although parents may not give any history of toxin ingestion; with the aid of pulse-oximetry and blood gas analysis, we can diagnose methemoglobinemia. Prompt recognition of this condition is required in emergency situations to institute early methylene blue therapy. We report an unusual case of severe toxic methemoglobinemia, which did not respond to methylene blue, but was successfully managed with exchange transfusion. PMID:24872659

  3. Evidence for PSP in mussels in Trinidad.

    PubMed

    Ammons, D; Rampersad, J; Poli, M A

    2001-06-01

    Herein we present the first evidence for the presence of Paralytic Shellfish Poison (PSP) in Trinidadian waters. The toxin was found in a meat extract of the mussel, Perna viridis. PSP has not previously been demonstrated in the shellfish of Caribbean islands. The presence of PSP in Trinidad is therefore significant in that it presents an opportunity to better understand the dynamics of PSP and algal blooms in both a region and island environment not normally associated with PSP.P. viridis is not native to Trinidad, but rather originates from eastern Asia. It presented itself only recently in Trinidadian waters. Interestingly, shellfish consumption and algal blooms have had a long history of coexistence in Trinidad without any record of human intoxications. In this context, potential Public Health implications of finding PSP in a non-native shellfish species are briefly discussed. PMID:11137550

  4. Assessing the Exposure and Relative Sensitivity of Native Freshwater Mussels to Environmental Stressors and Laboratory Conditions

    EPA Science Inventory

    1. Expands the database for pesticide toxicity on native freshwater mussels. 2. Aids in determining any potential differences in toxic sensitivity of gravid female mussel attributed to age and laboratory holding times. 3. Aids in determining potential differences in juvenile ...

  5. Cellular biomarkers for monitoring estuarine environments: transplanted versus native mussels.

    PubMed

    Nigro, M; Falleni, A; Barga, I Del; Scarcelli, V; Lucchesi, P; Regoli, F; Frenzilli, G

    2006-05-25

    In developed countries, estuarine environments are often subjected to chemical pollution, whose biological impact is profitably evaluated by the use of multi-biomarker approaches on sentinel species. In this paper, we investigate genotoxicity and lysosomal alterations in the Mediterranean mussel (Mytilus galloprovincialis), from the estuary of the River Cecina (Tuscany, Italy), selected as "pilot basin" within the Water Frame Directive (2000/60 European Community). Both native and 1 month transplanted mussels were used in order to compare these two approaches in terms of sensitiveness of specific biomarker responses. Genotoxic effects were evaluated as strand breaks, by single cell gel electrophoresis (or Comet assay), and as chromosomal alterations, by the micronucleus test in gill cells. Lysosomal alterations were assessed by the neutral red retention time (in haemocytes), lipofuscin accumulation and ultrastructure (in digestive cells). Heavy metal bioaccumulation was also analysed. Mussels from the River Cecina showed a general alteration of all the biomarkers investigated, accompanied by an elevation of tissue metal levels. However, some differences in specific responses occurred between transplanted and native mussels. Early biomarkers, such as those based on DNA and lysosomal membrane integrity, were induced at similar degree in native and transplanted mussels; while alterations resulting from cumulative events, as the increase of micronuclei frequency were much more elevated in native specimens (23.1+/-7.6) than in transplanted (9.3+/-4.7) and reference ones (5.8+/-5.2). Similarly, the comparison between lipofuscin accumulation and mean lysosomal diameter in impacted and control sites, gave significant differences exclusively with transplanted mussels. These results suggest that the parallel use of caged and native mussels in environmental biomonitoring can improve the characterization of the study area. PMID:16480782

  6. 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.

  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 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

  8. 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

  9. Ingestion and potential risks to wildlife from Exxon Valdez oil residues in mussels

    SciTech Connect

    Hartung, R.

    1995-12-31

    Mussels are important bioaccumulators of polycyclic aromatic hydrocarbons (PAHs), a toxicologically important fraction of crude oils. In some dense mussel beds in Prince William Sound, oil and PAH residues derived from the Exxon Valdez Oil Spill (EVOS) have persisted. The potential risks to wildlife from the consumption of these mussels are related to the degree of contamination of the mussels, the dietary intake of mussels, and the toxicity of the oils. Sea Otters (Enhydra lutris), Harlequin Ducks (Histrionicus histrionicus), and American Black Oystercatchers (Haematopus bachmanil) were identified as species that consumed significant quantities of mussels. The consumption of mussels was estimated from the percentage of mussels in the diet and the caloric requirements of each species. Caloric requirements were taken either from direct observations or calculated from allometric equations adjusted for nonbasal energy expenditures. Daily intakes of oils were estimated from the percentage of PAHs in oils, PAH levels in mussels from contaminated beds, and mussel consumption by these species. The highest estimated daily oil intake occurred in Black Oystercatchers at 22 mg/kg bodyweight, assuming that these birds consumed mussels at the 95th percentile of oil contamination and that 75% of the caloric requirements are obtained from mussels. These levels of estimated oil ingestion are considerably lower than levels which have been found to produce toxicological effects in extended feeding studies in surrogate species.

  10. DNA ADDUCTS IN MARINE MUSSEL MYTILUS GALLOPROVINCIALIS LIVING IN POLLUTED AND UNPOLLUTED ENVIRONMENTS

    EPA Science Inventory

    We have used a generally applicable 32P-postlabeling assay to examine for the presence of DNA adducts in mussels experimentally exposed to known carcinogens and in mussels collected from sites impacted by wastewaters. Mussels exposed to seawater artificially polluted with 2-amino...

  11. Native Mussels Alter Nutrient Availability and Reduce Blue-Green Algae Abundance

    EPA Science Inventory

    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...

  12. Free amino acid pattern in blue mussel (Mytilus edulis) exposed to crude oil

    SciTech Connect

    Soini, J.; Rantamaeki, P.

    1985-12-01

    In this study the authors investigated changes of free amino acid levels in different tissues of Mytilus edulis exposed to low concentrations of crude oil in a short term study. This investigation was accomplished in the northern area of the Baltic Sea, in the Archipelago of Turku. In this area the salinity of the sea water varies between 6-7%. Mytilus edulis lives there in its extreme conditions and it is therefore especially sensitive to disturbances in its environment.

  13. Evidence of Anti-Proliferative Activities in Blue Mussel (Mytilus edulis) By-Products

    PubMed Central

    Beaulieu, Lucie; Thibodeau, Jacinthe; Bonnet, Claudie; Bryl, Piotr; Carbonneau, Marie-Elise

    2013-01-01

    Shellfish waste components contain significant levels of high quality protein and are therefore a potential source for biofunctional high-value peptides. The feasibility of applying a pilot scale enzymatic hydrolysis process to whole Mytilus edulis and, by fractionation, recover hydrolysates presenting a biological activity of interest, was evaluated. Fractions were tested on four immortalized cancerous cell lines: A549, BT549, HCT15 and PC3. The 50 kDa fraction, enriched in peptides, presented anti-proliferative activity with all cell lines and results suggest a bioactive molecule synergy within the fraction. At a protein concentration of 44 µg/mL, the 50 kDa fraction induced a mortality of 90% for PC3, 89% for A549, 85% for HCT15 and of 81% for BT549 cell lines. At the low protein concentration of only 11 µg/mL the 50 kDa fraction still entails a cell mortality of 76% for A549 and 87% for PC3 cell lines. The 50 kDa fraction contains 56% of proteins, 3% of lipids and 6% of minerals on a dry weight basis and the lowest levels detected of taurine and methionine and highest levels of threonine, proline and glycine amino acids. The enzymatic hydrolysis process suggests that Mytilus edulis by-products should be viewed as high-valued products with strong potential as anti-proliferative agent and promising active ingredients in functional foods. PMID:23535393

  14. A Novel Mitochondrial Genome Organization for the Blue Mussel, Mytilus Edulis

    PubMed Central

    Hoffmann, R. J.; Boore, J. L.; Brown, W. M.

    1992-01-01

    The sequence of 13.9 kilobases (kb) of the 17.1-kb mitochondrial genome of Mytilus edulis has been determined, and the arrangement of all genes has been deduced. Mytilus mitochondrial DNA (mtDNA) contains 37 genes, all of which are transcribed from the same DNA strand. The gene content of Mytilus is typically metazoan in that it includes genes for large and small ribosomal RNAs, for a complete set of transfer RNAs and for 12 proteins. The protein genes encode the cytochrome b apoenzyme, cytochrome c oxidase (CO) subunits I-III, NADH dehydrogenase (ND) subunits 1-6 and 4L, and ATP synthetase (ATPase) subunit 6. No gene for ATPase subunit 8 could be found. The reading frames for the ND1, COI, and COIII genes contain long extensions relative to those genes in other metazoan mtDNAs. There are 23 tRNA genes, one more than previously found in any metazoan mtDNA. The additional tRNA appears to specify methionine, making Mytilus mtDNA unique in having two tRNA(Met) genes. Five lengthy unassigned intergenic sequences are present, four of which vary in length from 79 to 119 nucleotides and the largest of which is 1.2 kb. The base compositions of these are unremarkable and do not differ significantly from that of the remainder of the mtDNA. The arrangement of genes in Mytilus mtDNA is remarkably unlike that found in any other known metazoan mtDNA. PMID:1386586

  15. The use of transplanted mussels in the California State Mussel Watch Program

    SciTech Connect

    Stephenson, M.D.; Ichikawa, G.S.; Goetzl, J.

    1995-12-31

    Many contaminant programs have been established to study the geographical distributions of potential pollutants, but unfortunately, many have relied solely on resident bivalves. This approach limits the versatility of monitoring programs in that residents are not often found in all the places necessary to sample and there are factors which are inherent in using residents that confound the results. The California State Mussel Watch Program has relied heavily on transplants because they eliminate much of the variation inherent in using residents and they can be transplanted almost anywhere. Examples are given that demonstrate the advantages of using transplants over residents.

  16. 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.

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

    USGS Publications Warehouse

    Ram, Jeffrey L.; Nichols, S. Jerrine

    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.

  18. 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. PMID:27086073

  19. Influence of mussel biological variability on pollution biomarkers.

    PubMed

    González-Fernández, Carmen; Albentosa, Marina; Campillo, Juan A; Viñas, Lucía; Fumega, José; Franco, Angeles; Besada, Victoria; González-Quijano, Amelia; Bellas, Juan

    2015-02-01

    This study deals with the identification and characterization of biological variables that may affect some of the biological responses used as pollution biomarkers. With this aim, during the 2012 mussel survey of the Spanish Marine Pollution monitoring program (SMP), at the North-Atlantic coast, several quantitative and qualitative biological variables were measured (corporal and shell indices, gonadal development and reserves composition). Studied biomarkers were antioxidant enzymatic activities (CAT, GST, GR), lipid peroxidation (LPO) and the physiological rates integrated in the SFG biomarker (CR, AE, RR). Site pollution was considered as the chemical concentration in the whole tissues of mussels. A great geographical variability was observed for the biological variables, which was mainly linked to the differences in food availability along the studied region. An inverse relationship between antioxidant enzymes and the nutritional status of the organism was evidenced, whereas LPO was positively related to nutritional status and, therefore, with higher metabolic costs, with their associated ROS generation. Mussel condition was also inversely related to CR, and therefore to SFG, suggesting that mussels keep an "ecological memory" from the habitat where they have been collected. No overall relationship was observed between pollution and biomarkers, but a significant overall effect of biological variables on both biochemical and physiological biomarkers was evidenced. It was concluded that when a wide range of certain environmental factors, as food availability, coexist in the same monitoring program, it determines a great variability in mussel populations which mask the effect of contaminants on biomarkers. PMID:25483414

  20. Do invasive mussels restrict offshore phosphorus transport in Lake Huron?

    PubMed

    Cha, Yoonkyung; Stow, Craig A; Nalepa, Thomas F; Reckhow, Kenneth H

    2011-09-01

    Dreissenid mussels were first documented in the Laurentian Great Lakes in the late 1980s. Zebra mussels (Dreissena polymorpha) spread quickly into shallow, hard-substrate areas; quagga mussels (Dreissena rostriformis bugensis) spread more slowly and are currently colonizing deep, offshore areas. These mussels occur at high densities, filter large water volumes while feeding on suspended materials, and deposit particulate waste on the lake bottom. This filtering activity has been hypothesized to sequester tributary phosphorus in nearshore regions reducing offshore primary productivity. We used a mass balance model to estimate the phosphorus sedimentation rate in Saginaw Bay, a shallow embayment of Lake Huron, before and after the mussel invasion. Our results indicate that the proportion of tributary phosphorus retained in Saginaw Bay increased from approximately 46-70% when dreissenids appeared, reducing phosphorus export to the main body of Lake Huron. The combined effects of increased phosphorus retention and decreased phosphorus loading have caused an approximate 60% decrease in phosphorus export from Saginaw Bay to Lake Huron. Our results support the hypothesis that the ongoing decline of preyfish and secondary producers including diporeia (Diporeia spp.) in Lake Huron is a bottom-up phenomenon associated with decreased phosphorus availability in the offshore to support primary production. PMID:21812427

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

    USGS Publications Warehouse

    Michael, Holliman F.; Davis, D.; Bogan, A.E.; Kwak, T.J.; Gregory, Cope W.; Levine, J.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 vivo evaluation of the structure, function, and integrity of mussel soft tissues. ?? 2008, The American Microscopical Society, Inc.

  2. 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.

  3. Dynamics of submersible mussel rafts in waves and current

    NASA Astrophysics Data System (ADS)

    Wang, Xin-xin; Swift, M. Robinson; Dewhurst, Tobias; Tsukrov, Igor; Celikkol, Barbaros; Newell, Carter

    2015-06-01

    To investigate the dynamics of submersible mussel rafts, the finite element program Aqua-FE™, developed by the University of New Hampshire (UNH), was applied to rafts moored at the surface and submerged. The submerged configuration is used to reduce wave forcing and to avoid contact with floating ice during winters in northern waters. Each raft consists of three pontoons connected by a grid framework. Rafts are intended to support densely spaced mussel ropes hung from the framework. When submerged, the pontoons are flooded, and the raft is held vertically by floats attached by lines. The computer models were developed in Aqua-FE™ to simulate the effects of waves and current. They were validated by comparison with wave tank results by use of a 1/10 scale raft physical model. Comparisons showed good agreement for the important heave (vertical) and pitch (rotational) motions, though there was a tendency towards conservative results for wave and current drag. Full-scale simulations of surface and submerged single raft and two rafts connected in tandem were performed. Submerged raft wave response was found to be reduced relative to that at the surface for both the single and two-raft configurations. In particular, the vertical motion of mussel rope connection points was significantly reduced by submergence, resulting in reduced potential for mussel drop-off. For example, the maximum vertical velocities of mussel rope attachment points in the submerged two raft case were 7%-20% of the corresponding velocities when at the surface.

  4. Sublethal effects of a chlorinated and heated effluent on the physiology of the mussel, Mytilus edulis L.: a reduction in fitness for survival?

    PubMed

    Mazik, Krysia; Hitchman, Natasha; Quintino, Victor; Taylor, Colin J L; Butterfield, Jonathan; Elliott, Michael

    2013-12-15

    Coastal power stations entrain large volumes of cooling water, requiring biocidal treatment to prevent biological fouling. Discharged effluent is both heated and contaminated with residual traces of biocide and so it is necessary to quantify the impacts of this discharge. Cooling water from Heysham 2 nuclear power station, NW England, UK, is discharged to the intertidal area, via a culvert (to minimise erosion and maximise dilution and dispersion by directing the effluent into the receiving water at all states of the tide) within which the effluent is contained at low water. The culvert and surrounding coastal area support a population of blue mussels (Mytilus edulis). Mussel health was determined along a gradient of exposure, using three physiological indices: Scope for Growth, Gonad Mantle Index and Somatic Condition Index (K Factor). The Mussels within the culvert exhibited reduced physiological index values compared to an external site. A trend was identified down the length of the culvert, representing a gradient of exposure and indicating a potential negative effect on growth and reproductive output. PMID:24210945

  5. Evaluation of a recirculating pond system for rearing juvenile freshwater mussels at White Sulphur Springs National Fish Hatchery, West Virginia, U.S.A.

    USGS Publications Warehouse

    Mummert, A.; Newcomb, T.J.; Neves, R.J.; Parker, B.

    2006-01-01

    A recirculating double-pond system at White Sulphur Springs National Fish Hatchery in West Virginia, U.S.A., was evaluated for suitability for culturing juvenile freshwater mussels. Newly metamorphosed juveniles of Villosa iris and Lampsilis fasciola were placed in the system, and their growth and survival were evaluated for 94 days. Throughout the study, parameters of water quality remained within ranges suitable for mussel survival. Planktonic algal densities in the pond system ranged from 2850 to 6892 cells/ml. Thirty-seven algal taxa were identified, primarily green algae (Chlorophyta), diatoms (Bacillariophyceae), and blue-green algae (Cyanoprokaryota). Over the culture period, juveniles of L. fasciola experienced significantly lower (p < 0.001) survival (6.3% ?? 4.5) than those of V. iris (49.8% ?? 14.5). The very low survival rate of L. fasciola may indicate a failure of the flow-through pond environment to meet its habitat requirements or that variable microhabitat conditions within culture containers existed. Growth did not differ significantly between the species (p = 0.13). Survival of V. iris and growth of both species were similar to previous trials to culture juvenile mussels. Survival rates as high as 66.4% at 93 days for V. iris suggest that juveniles of some riverine species can be successfully cultured in a recirculating pond environment.

  6. Toxic and nutrient element concentrations in soft tissues of zebra and quagga mussels from Lakes Erie and Ontario.

    PubMed

    Rutzke, M A; Gutenmann, W H; Lisk, D J; Mills, E L

    2000-06-01

    Zebra and quagga mussels were collected from Lakes Erie and Ontario in 1997 and the soft mussel tissues were analyzed for Ca, Cd, Cr, Cu, Fe, Hg, K, Mg, Mn, Mo, Na, Ni, Pb, Se, Sr, V and Zn. No consistent relationships were apparent when comparing element concentrations in soft mussel tissues and mussel type, size range or sampling location. Literature dealing with the absorption of metals by both mussel types is reviewed. PMID:10789974

  7. 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.

  8. Blue honeysuckle list 47

    Technology Transfer Automated Retrieval System (TEKTRAN)

    This manuscript summarizes descriptions for two newly released Lonicera caerulea L., blue honeysuckle, cultivars released for northern production. This fruit is popular in Russia and in Japan, particularly Hokkaido. It has possibility as a new fruit cultivar for North America. The University of Sask...

  9. Are Predators Limiting Zebra Mussel Colonization of Unionid Mussels in Great Lake Coastal Wetlands?

    NASA Astrophysics Data System (ADS)

    de Szalay, F. A.; Bowers, R.

    2005-05-01

    Although many native mollusc populations have been eliminated in the Laurentian Great Lakes by the exotic zebra mussel, recent surveys have found abundant unionid (Bivalvia: Unionidae) populations in some coastal wetlands. Unionid burrowing in soft sediments and predation by fish have been shown to reduce numbers of attached zebra mussels, and we tested these factors in a Lake Erie coastal wetland. In 2002, we held live unionids (Leptodea fragilis, Quadrula quadrula) and Pyganodon grandis shells in exclosures with wire mesh bottoms that were buried to sediment depths of either 5, 10, or 20 cm. After 2 months, numbers of attached dreissenids on unionids were significantly higher inside all exclosure treatments than outside exclosures. This indicated that either unionid burrowing was prevented in all sediment depth treatments or molluscivores were excluded by exclosures. In 2004, we measured dreissenid colonization on Q. quadrula and PVC plates in bottomless exclosures with different mesh sizes. After 6 months, dreissenid numbers on PVC plates and on Q. quadrula in 2.5 cm X 2.5 cm and 5 cm X 10 cm mesh exclosures were significantly higher than in open exclosures. These data suggest that molluscivores are important in limiting dreissenids in Great Lake coastal wetlands.

  10. IMPACT OF OXYGEN CONCENTRATION ON ZEBRA MUSSEL MORTALITY

    SciTech Connect

    Daniel P. Molloy

    2003-01-27

    These tests have indicated that the bacterium Pseudomonas fluorescens strain CL0145A is effective at killing zebra mussels in environments having dissolved oxygen (DO) concentrations ranging from very low to very high. The results suggest that the highest mussel kill can be achieved in moderately to highly aerated environments, while kill may be 0-20% lower under conditions of very low oxygen. For example, under highly oxygenated conditions 97% kill was achieved while conditions having low DO produced 79% mussel kill. Service water measured in a local power plant indicated that DO concentrations were in the range of 8-9 ppm (e.g., highly aerated) within their pipes. Therefore, we will not expect to see decreases in the efficacy of CL0145A treatments due to oxygen levels within such power plant pipes.

  11. IMPACT OF FIVE TREATMENT FACTORS ON MUSSEL MORTALITY

    SciTech Connect

    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 to the pipe is a constant; and (5) whether the water temperature is between 13 C and 23 C.

  12. Perforation of esophagus and subsequent mediastinitis following mussel shell ingestion

    PubMed Central

    Park, Il Hwan; Lim, Hyun Kyo; Song, Seung Woo

    2016-01-01

    Esophageal perforation is a very rare occurrence because accidental swallowing of foreign bodies is uncommon in adults. Thus, perforation due to swallowing of a foreign body and subsequent development of mediastinitis is rarely encountered by physicians. We experienced such a case and described an adult male patient who had perforated esophagus after accidentally swallowing a mussel shell. The patient visited our emergency department complaining of painful dysphagia for 4 days. A review of history revealed that he consumed a spicy seafood noodle soup containing mussel shells 4 days ago. Computed tomography (CT) of the chest showed the foreign body in the esophagus and pneumomediastinum was identified. We removed the mussel shell fragment using rigid esophagoscopy; explo-thoracotomy, debridement of mediastinal abscess and irrigation were performed.

  13. DNA damage and apoptosis in the mussel Mytilus galloprovincialis.

    PubMed

    Micić, Milena; Bihari, Nevenka; Jaksić, Zeljko; Müller, Werner E G; Batel, Renato

    2002-04-01

    The effects of known genotoxic substances (4-nitroquinoline-N-oxide, benzo[a]pyrene, teniposide, etoposide, cycloheximide, tributyltin) on human cells (FLC, HL-60) and on mussels were investigated. The correlations between formation of DNA strand breaks and DNA fragmentation characteristic for the process of apoptosis were estimated. Strand breaks induced by 4-nitroquinoline-N-oxide and benzo[a]pyrene did not correlate with DNA fragmentation detected in the process of apoptosis. Induction of internucleosomal DNA fragmentation in HL-60 cells was initiated by teniposide, etoposide and tributyltin, while in the gills of mussels this was detected only with tributyltin. Levels of DNA strand breaks in natural mussel populations, living at locations under the influence of urban and industrial wastes, do not mirror the apoptotic processes. PMID:11939292

  14. 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.

  15. Seasonal, geographic and individual variation of okadaic acid content in cultivated mussels in Sweden.

    PubMed

    Edebo, L; Lange, S; Li, X P; Allenmark, S; Lindgren, K; Thompson, R

    1988-11-01

    In Western Europe the dinoflagellate toxin, okadaic acid (OA) has been the main cause of diarrheic shellfish poisoning (DSP). Chemical determination of OA in mussels by homogenization of the hepatopancreas, extraction, purification, reaction with 9-anthryldiazomethane (ADAM), HPLC-separation, and fluorometric quantification has been used for weekly monitoring of mussel growing farms and to control harvested mussels. Within a week, substantial rises (from 0.41 to 5.4 micrograms OA/g hepatopancreas) as well as great reductions (from 7.2 to 1.8 micrograms/g hepatopancreas) were recorded. The rapid rise implies that weekly sampling is not sufficient to ensure that mussels are free from toxic levels of OA. The rapid decrease reveals that efficient toxin clearance mechanisms exist in the mussels. Substantial OA clearance occurs also at low temperatures (1.4-3 degrees C). Within a mussel growing site the OA concentrations could differ considerably between adjacent mussels (0.63 and 4.2 micrograms OA/g hepatop.) and even more between mussels grown at different depths along the same rope (0.63 and 10 micrograms OA/g hepatop.). These data emphasize the importance of sampling in studies on DST in mussels. Great differences between the different mussel growing sites were also observed. These data have been discussed with respect to the spread of the toxin by the sea, and the possibilities of reducing the exposure of the mussels to the toxic algae. PMID:3196475

  16. Survey design for detecting rare freshwater mussels

    USGS Publications Warehouse

    Smith, D.R.

    2006-01-01

    A common objective when surveying freshwater mussels is to detect the presence of rare populations. In certain situations, such as when endangered or threatened species are potentially in the area of a proposed impact, the survey should be designed to ensure a high probability of detecting species presence. Linking survey design to probability of detecting species presence has been done for quantitative surveys, but commonly applied designs that are based on timed searches have not made that connection. I propose a semiquantitative survey design that links search area and search efficiency to probability of detecting species presence. The survey can be designed to protect against failing to detect populations above a threshold abundance (or density). I illustrate the design for surveys to detect clubshell (Pluerobema clava) and northern riffleshell (Epioblasma torulosa rangiana) in the Allegheny River. Monte Carlo simulation indicated that the proposed survey design performs well under a range of spatial distributions and low densities (<0.05 m2) where search area is sufficient to ensure that the probability of detecting species presence is predicted to be ???0.85. ?? 2006 by The North American Benthological Society.

  17. Proceedings: Third International Zebra Mussel Conference, 1993

    SciTech Connect

    Tsou, J.L.; Mussalli, Y.G.

    1993-06-01

    This Third International Conference on Zebra Mussels was held on February 23--26, 1993 in Toronto, Ontario, Canada. The Conference was sponsored by American Water Works Association Research Foundation, Electric Power Research Institute, Environment Canada - Fisheries and Oceans, Great Lakes Seal Grant Network, Ontario Hydro, the Ontario Ministry of the Environment, and Ontario Ministry of Natural Resources to bring together representatives of utilities, manufacturers, researchers, and consultants. There were 105 papers presented in 16 sessions over 4 days, typically with 2 sessions running concurrently. These sessions were devoted to the following general topics: General Information, Biological and Ecological Considerations, Chemical Treatments, and Non-Chemical Treatments. A panel discussion devoted to the same topics was conducted on the second day, two concurrent special meetings (Workshop on Application of Electric Power Technology for Biofouling and Research Protocol Panel Meeting) were held on the third day, and a poster session containing 56 poster papers was held on the fourth day. Approximately 700 people attended this conference. This report contains selected technical papers from the formal presentations and the poster session. Of these 49 selected papers, there are 9 papers related to general information, 8 papers related to biological and ecological considerations, 20 papers related to chemical treatments, and 12 papers related to nonchemical treatments. Individual papers have been cataloged separately.

  18. Experimental trials on the feasibility of offshore seed production of the mussel Mytilus edulis in the German Bight: installation, technical requirements and environmental conditions

    NASA Astrophysics Data System (ADS)

    Buck, Bela Hieronymus

    2007-06-01

    This study summarizes the activities and findings during a 2 year investigation on the grow-out of blue mussels ( Mytilus edulis) and the technical requirements to withstand harsh weather conditions at an offshore location. The experimental sites were two different test areas, each 5 ha in size, 12-15 m in depth, in the vicinity of the offshore lighthouse “Roter Sand” located 15-17 nautical miles northwest of the city of Bremerhaven (Germany). Two versions of submerged longline systems were deployed: a conventional polypropylene longline in 2002 as well as a steel hawser longline in 2003, both featuring different versions of buoyancy modes. The spat collectors and grow-out ropes were suspended perpendicular from the horizontal longline for several months beginning in March of each respective year. The test sites were visited and sampled on a monthly basis using research vessels. Larval abundances in the surrounding water column reached numbers of up to 1,467 individuals m-3. Post-larval settlement success varied through the entire experimental period, ranging from 29 to 796 individuals of spat per meter of collector. Settled mussels reached a shell length of up to 28 mm 6 months after settlement. Based on the growth rates observed for the seed, it is projected that mussels would reach market size (50 mm) in 12-15 months post settlement, and at the observed densities, each meter of collector rope could yield 10.9 kg of harvestable mussels. The polypropylene line resisted storm conditions with wind waves of up to 6.4 m and current velocities of 1.52 m s-1 and was retrieved in autumn of 2002. In contrast, the steel hawser-based line did not withstand the harsh weather conditions. The steel-based line consisted of six twisted strands that were untwisted by the strong currents and turbulences and consequently the individual strands were torn. Additionally, the line was accidentally cut by a yacht in July 2003. The biological study revealed that the tested location

  19. Host-Fish Identification and Early Life Thermal Requisites of the Federal Endangered Winged Mapleleaf Mussel (Quadrula fragosa)

    NASA Astrophysics Data System (ADS)

    Steingraeber, M. T.; Hove, M. C.; Bartsch, M. R.; Kalas, J. A.; Newton, T. J.

    2005-05-01

    The winged mapleleaf mussel (Quadrula fragosa) is a federal endangered species with only one known reproducing population. Controlled propagation is needed to aid in recovering this species, but little is known of its specific early life-history requirements, including the identity of host-fish that facilitate transformation of its parasitic glochidia (larvae) into free-living juveniles. In autumn 2003, we initiated three winged mapleleaf host-fish identification tests that were each conducted in different thermal regimes. Results of the two shorter-term tests at warmer temperatures identified blue catfish (Ictalurus furcatus) and channel catfish (I. punctatus) as suitable host-fish species. Close examination of these test data allowed us to empirically estimate: the minimum daily mean water temperature (9.24°C) required for glochidia to grow and develop into juveniles; and the cumulative water temperature units of net daily growth (395°C•d)needed to initiate peak juvenile recovery. We applied these findings to the longer-term third test and predicted with great accuracy (±7 d) the initial date of peak juvenile mussel recovery after >8 months development in a colder, more natural thermal regime. Our final results also indicated a consistent daily temperature >17°C is needed to trigger the large-scale release of winged mapleleaf juveniles from the gills of host-fish.

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

    USGS Publications Warehouse

    French, John R. P., III; 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

  1. Mutagenicity test using Vibrio harveyi in the assessment of water quality from mussel farms.

    PubMed

    Ruiz, Yolanda; Suárez, Pilar; Alonso, Ana; Longo, Elisa; San Juan, Fuencisla

    2013-05-15

    This work analyses the mutagenicity of seawater from mussel farms using the Vibrio harveyi mutagenicity test and its relationship with the accumulated pollutants and the development of gonadal neoplasia in mussels. Histological disorders identified as germinoma were observed in the gonad of Mytilus galloprovincialis during the period of study. The prevalence of this pathology is significantly correlated with certain levels of pollutants accumulated in mussels, mainly of PAHs and PCBs, whose toxic equivalents were calculated as EROD induction equivalency. The mutagenicity and toxicity of the water surrounding mussel's farms is clearly correlated with the pollutants accumulated and with the neoplasia prevalence in mussels. Such correlations are corroborated by a multivariate analysis. Our results conclude with the utility of V. harveyi test as an optimal and rapid method in the monitoring of the quality of the water from mussel farms and as a tool to control the risks of pollution on mussel production and its safety for human food. PMID:23510693

  2. World mussel watch database. National status and trends program for marine environmental quality: Technical memo

    SciTech Connect

    Cantillo, A.Y.

    1997-04-01

    The Global Ocean Observing System (GOOS) is an internationally cooordinated system for systematic operational data collection and analysis. This contribution to GOOS is an attempt to determine the levels of contaminants in mussels and oysters collected worldwide and to compare the results with the long-term Mussel Watch programs of the United States and France. A comprehensive literature search of studies using any species of mussels and/or oysters worldwide to monitor the levels of trace metals and organic contaminants was conducted and the data compiled into the World Mussel Watch database. Data sources and statistics of the database are included. Results of the World Mussel Watch and the US and France Mussel Watch programs were compared and typical levels of some trace metals in uncontaminated mussels and oysters were calculated.

  3. Enemies with benefits: parasitic endoliths protect mussels against heat stress.

    PubMed

    Zardi, G I; Nicastro, K R; McQuaid, C D; Ng, T P T; Lathlean, J; Seuront, L

    2016-01-01

    Positive and negative aspects of species interactions can be context dependant and strongly affected by environmental conditions. We tested the hypothesis that, during periods of intense heat stress, parasitic phototrophic endoliths that fatally degrade mollusc shells can benefit their mussel hosts. Endolithic infestation significantly reduced body temperatures of sun-exposed mussels and, during unusually extreme heat stress, parasitised individuals suffered lower mortality rates than non-parasitised hosts. This beneficial effect was related to the white discolouration caused by the excavation activity of endoliths. Under climate warming, species relationships may be drastically realigned and conditional benefits of phototrophic endolithic parasites may become more important than the costs of infestation. PMID:27506855

  4. 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.

  5. Enemies with benefits: parasitic endoliths protect mussels against heat stress

    PubMed Central

    Zardi, G. I.; Nicastro, K. R.; McQuaid, C. D.; Ng, T. P. T.; Lathlean, J.; Seuront, L.

    2016-01-01

    Positive and negative aspects of species interactions can be context dependant and strongly affected by environmental conditions. We tested the hypothesis that, during periods of intense heat stress, parasitic phototrophic endoliths that fatally degrade mollusc shells can benefit their mussel hosts. Endolithic infestation significantly reduced body temperatures of sun-exposed mussels and, during unusually extreme heat stress, parasitised individuals suffered lower mortality rates than non-parasitised hosts. This beneficial effect was related to the white discolouration caused by the excavation activity of endoliths. Under climate warming, species relationships may be drastically realigned and conditional benefits of phototrophic endolithic parasites may become more important than the costs of infestation. PMID:27506855

  6. The availability and quality of the mussel prey ( Mytilus edulis) of oystercatchers ( Haematopus ostralegus)

    NASA Astrophysics Data System (ADS)

    Goss-Custard, J. D.; West, A. D.; Dit Durell, S. E. A. LeV

    Spatial variations in the availability and quality of the mussel Mytilus edulis food supply of Oystercatchers Haematopus ostralegus on the Exe estuary, England, are described. Oystercatchers open mussels by stabbing into gaping mussels (or prising open closed ones) or by hammering a hole in either the dorsal or ventral shells. Spatial variations in the food supply are considered at four scales. In decreasing order of size, these are (i) whole mussel beds, (ii) zones within a mussel bed, (iii) different places within one zone, and (iv) different places within one clump of mussels. The first two scales are clearly related to exposure time. Both between and within the 12 main mussel beds of the estuary, most upshore mussels are up to 10% less likely than downshore mussels to be hidden under mud. However, upshore mussels of a given length contain less flesh, have thicker ventral shells and, except on high-level beds subject to wave erosion, have thicker dorsal shells than downshore mussels. Mussels at the top of the shore also contain the highest infestations of the helminth parasite of Oystercatchers, Psilostomum brevicolle. At a particular shore level, mussels of a given length have less flesh and thicker shells, though only on the dorsal side, in areas of high mussel density. Within one clump, mussels of a given length with thick dorsal shells have more flesh than those with thin shells. In contrast, flesh content is slightly higher in mussels that are thin on the ventral side. Flesh content and shell thickness on both sides are unaffected by whether a mussel is visible at the edge of a clump or hidden inside. Simulations with a model of foraging Oystercatchers suggested that variations in mussel availability (visibility and shell thickness) and flesh content at all four scales could sometimes have an important influence on intake rate. Most published values of intake rates of Oystercatchers eating surface-dwelling mussels may be biassed (and often considerably over

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

    PubMed

    Hoy, Marshal S; Kelly, Kevin; Rodriguez, Rusty 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. PMID:21565008

  8. 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

  9. The Blue Emu

    NASA Technical Reports Server (NTRS)

    Descalzi, Doug; Gillett, John; Gordon, Carlton; Keener, ED; Novak, Ken; Puente, Laura

    1993-01-01

    The primary goal in designing the Blue Emu was to provide an airline with a cost efficient and profitable means of transporting passengers between the major cities in Aeroworld. The design attacks the market where a demand for inexpensive transportation exists and for this reason the Blue Emu is an attractive investment for any airline. In order to provide a profitable aircraft, special attention was paid to cost and economics. For example, in manufacturing, simplicity was stressed in structural design to reduce construction time and cost. Aerodynamic design employed a tapered wing which reduced the induced drag coefficient while also reducing the weight of the wing. Even the propulsion system was selected with cost effectiveness in mind, yet also to maintain the marketability of the aircraft. Thus, in every aspect of the design, consideration was given to economics and marketability of the final product.

  10. Prostatic blue nevus.

    PubMed

    Anderco, Denisa; Lazăr, Elena; Tăban, Sorina; Miclea, Fl; Dema, Alis

    2010-01-01

    We report the case of a 69-year-old patient with no significant personal urological history. The clinical and ultrasound examination revealed a prostatic gland with increased volume and homogenous appearance. After transurethral resection, multiples gray-brown-blackish prostatic chips were obtained, which could be confused with a malignant melanoma. The histological routine examination in conjunction with the histochemical (Fontana-Masson) and immunohistochemical (S100, HMB45) reactions established the diagnosis of prostatic blue nevus. The presence of melanin in prostatic tissue is an unusual aspect, being encountered three distinct lesions: blue nevus, melanosis and malignant melanoma. Recognition and correct classification of each of these three entities is fundamental, concerning the clinical and prognosis implications. PMID:20809037

  11. Diet and population metrics of the introduced blue catfish population in the Altamaha, River, GA

    USGS Publications Warehouse

    Bonvechio, Timothy F.; Jennings, Cecil A.

    2011-01-01

    Blue catfish (Ictalurus furcatus) were first detected in the Altamaha River, Georgia, during an access creel survey in 2005 and subsequently in 2006 during annual ictalurid sampling. Introduction of this species in the Altamaha River is believed to have occurred via escape from normal upstream reservoir releases from Lake Sinclair and Lake Oconee. Relative abundance, as indexed by electrofishing catch rate (fish per hour), has increased from 2.9±1.0 SE in 2006 to 38.8±8.2 SE in 2011. The size of blue catfish captured ranged from 56 to 820 mm total length and 0.001 to 7.7 kg. Using otoliths obtained in 2010 (n=214), age of fish ranged from 0 to 6 yrs, which indicated a relatively young population. The catch-curve analysis resulted in an instantaneous mortality rate (Z) of 0.75. Despite concerns of blue catfish predation on native fishes and mussels, a diet analysis of blue catfish (n=257) obtained in 2010 revealed that diets of fish in all size groups were dominated by the introduced Asiatic clam (Corbicula fluminea). This study describes a recently introduced blue catfish population in an Atlantic coastal plain river and provides insight on possible ecological effects during the early phases of establishment. These results offer an early status assessment of the invasion dynamics before the system has had time to reach a new equilibrium state.

  12. Voyager 1 'Blue Movie'

    NASA Technical Reports Server (NTRS)

    2000-01-01

    This is the original Voyager 'Blue Movie' (so named because it was built from Blue filter images). It records the approach of Voyager 1 during a period of over 60 Jupiter days. Notice the difference in speed and direction of the various zones of the atmosphere. The interaction of the atmospheric clouds and storms shows how dynamic the Jovian atmosphere is.

    As Voyager 1 approached Jupiter in 1979, it took images of the planet at regular intervals. This sequence is made from 66 images taken once every Jupiter rotation period (about 10 hours). This time-lapse movie uses images taken every time Jupiter longitude 68W passed under the spacecraft. These images were acquired in the Blue filter from Jan. 6 to Feb. 3 1979. The spacecraft flew from 58 million kilometers to 31 million kilometers from Jupiter during that time.

    This time-lapse movie was produced at JPL by the Image Processing Laboratory in 1979.

  13. Differential recruitment of introduced Pacific oysters and native mussels at the North Sea coast: coexistence possible?

    NASA Astrophysics Data System (ADS)

    Diederich, Susanne

    2005-04-01

    Pacific oysters ( Crassostrea gigas Thunberg 1793) have been introduced into the Wadden Sea (North Sea), where they settle on native mussel beds ( Mytilus edulis L.), which represent the only extensive insular hard substrata in this soft-sediment environment. As abundances of C. gigas rose, some mussel beds became increasingly overgrown with oysters, whereas others did not. Field experiments revealed that recruitment of C. gigas was higher in the lower intertidal than in the upper subtidal zone, that it was higher on conspecifics than on mussels, and that it was not affected by barnacle epigrowth except when settling on mussels. Mussel recruitment is known from inter- and subtidal zones. It occurred equally on oyster and mussel shells but showed a clear preference for barnacle epigrowth over clean shells. Assuming that settlement and recruitment are key processes for species abundances on the North Sea coast, it is predicted that the positive feedback in oyster settlement will lead to rapid reef formation of this invader at the expense of mussel beds. Mussels, however, may escape competitive exclusion by settling between or on the larger oysters especially when barnacles are abundant. Experimental patches with mussels were more often covered by fucoid algae ( Fucus vesiculosus forma mytili Nienburg) than patches with oysters, and oyster recruitment was poor underneath such algal canopies. Thus, fucoids may provide the native mussels with a refuge from the invading oysters and the two bivalves may coexist, provided food is not limiting.

  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. GPAW on Blue Gene/P

    NASA Astrophysics Data System (ADS)

    Romero, Nichols; Enkovaara, Jussi; Dulak, Marcin; Glinsvad, Christian; Larsen, Ask; Mortensen, Jens; Shende, Sameer; Morozov, Vitali; Greeley, Jeffrey

    2011-03-01

    Density function theory (DFT) is the most widely employed electronic structure method due to its favorable scaling with system size and accuracy for a broad range of molecular and condensed-phase systems. The advent of massively parallel supercomputers have enhanced the scientific community's ability to study larger system sizes. Ground state DFT calculations of systems with O (103) valence electrons can be routinely performed on present-day supercomputers. The performance of these massively parallel DFT codes at the scale of 1 - 10K execution threads are not well understood; even experienced DFT users are unaware of Amdahl's Law and the non-trivial scaling bottlenecks that are present in standard O (N3) DFT algorithms. The GPAW code was ported an optimized for the Blue Gene/P. We present our algorithmic parallelization strategy and interpret the results for a number of benchmark tests cases. Lastly, I will describe opportunities for computer allocations at the Argonne Leadership Computing Facility. This work has been supported by the Academy of Finland (Project 110013), Tekes MASI-program, Danish Center for Scientific Computing, Lundbeck Foundation, Office of Science of the U.S. Department of Energy under contract DE-AC02-06CH11357.

  16. Effects of different biotic substrata on mussel attachment.

    PubMed

    Ank, Glaucia; Porto, Tiago F; Pereira, Renato C; da Gama, Bernardo A P

    2009-01-01

    Surface colonization by invertebrates can be stimulated or inhibited by cues produced by biofilms, conspecifics or other macroorganisms. To study the effects of living substrata on the attachment of the brown mussel, Perna perna, two different approaches were employed: (1) mussels were distributed in sets of Petri dishes consisting of one sterile set (controls), three sets in which marine biofilms were allowed to develop in aquaria for 1, 7 or 15 days and another set that had been immersed in a natural marine environment for 1-day. There was no significant effect of biofilms on attachment, suggesting that neither age nor the source of the biofilm influenced attachment. (2) Mussels were suspended over PVC panels (controls) and over panels on which Balanus trigonus (Crustacea), Schizoporella errata (Bryozoa), Symplegma rubra or Didemnum speciosum (Ascidiacea) were present. Attachment was significantly higher on the controls and on B. trigonus than on colonial taxa such as S. rubra, S. errata and D. speciosum, probably due to antifouling defenses of these species. The results show that the composition of the biological substratum is an important factor affecting mussel behavior. PMID:19048423

  17. Interfacial pH during mussel adhesive plaque formation.

    PubMed

    Martinez Rodriguez, Nadine R; Das, Saurabh; Kaufman, Yair; Israelachvili, Jacob N; Waite, J Herbert

    2015-01-01

    Mussel (Mytilus californianus) adhesion to marine surfaces involves an intricate and adaptive synergy of molecules and spatio-temporal processes. Although the molecules, such as mussel foot proteins (mfps), are well characterized, deposition details remain vague and speculative. Developing methods for the precise surveillance of conditions that apply during mfp deposition would aid both in understanding mussel adhesion and translating this adhesion into useful technologies. To probe the interfacial pH at which mussels buffer the local environment during mfp deposition, a lipid bilayer with tethered pH-sensitive fluorochromes was assembled on mica. The interfacial pH during foot contact with modified mica ranged from 2.2 to 3.3, which is well below the seawater pH of ~ 8. The acidic pH serves multiple functions: it limits mfp-Dopa oxidation, thereby enabling the catecholic functionalities to adsorb to surface oxides by H-bonding and metal ion coordination, and provides a solubility switch for mfps, most of which aggregate at pH ≥ 7-8. PMID:25875963

  18. Induction of chromosomal aberrations in the mussel Mytilus galloprovincialis watch

    SciTech Connect

    Al-Sabti, K.; Kurelec, B.

    1985-11-01

    In this paper the authors present an investigation into the occurrence of chromosomal aberration (CA) induction in mussels. The feasibility of using this as an indicator of genotoxins under actual field conditions has been evaluated. Benzo(a)pyrene was used in these experiments.

  19. Interfacial pH during mussel adhesive plaque formation

    PubMed Central

    Rodriguez, Nadine R. Martinez; Das, Saurabh; Kaufman, Yair; Israelachvili, Jacob N.; Waite, J. Herbert

    2015-01-01

    Mussel (Mytilus californianus) adhesion to marine surfaces involves an intricate and adaptive synergy of molecules and spatio-temporal processes. Although the molecules, such as mussel foot proteins (mfps), are well characterized, deposition details remain vague and speculative. Developing methods for the precise surveillance of conditions that apply during mfp deposition would aid both in understanding mussel adhesion and translating this adhesion into useful technologies. To probe the interfacial pH at which mussels buffer the local environment during mfp deposition, a lipid bilayer with tethered pH-sensitive fluorochromes was assembled on mica. The interfacial pH during foot contact with modified mica ranged from 2.2−3.3, which is well below the seawater pH of ~8. The acidic pH serves multiple functions: it limits mfp-Dopa oxidation, thereby enabling the catecholic functionalities to adsorb to surface oxides by H-bonding and metal ion coordination, and provides a solubility switch for mfps, most of which aggregate at pH ≥ 7-8. PMID:25875963

  20. THREATENED AND ENDANGERED FRESHWATER FISH AND MUSSEL SPECIES RICHNESS

    EPA Science Inventory

    These data represent predicted current distributions of all US listed Threatened and Endangered freshwater fish and freshwater mussels in the Middle-Atlantic region. The data are available for both 8-digit HUCs and EMAP hexagons and represent total species counts for each spatia...

  1. Mussel fouling on the Celtic Sea Kinsale Field gas platforms

    NASA Astrophysics Data System (ADS)

    Southgate, T.; Myers, A. A.

    1985-06-01

    Fouling was investigated on Marathon Kinsale Field Alpha and Bravo platforms in the Celtic Sea between June 1978 and June 1981. In shallow depths, algae dominated, chiefly Polysiphonia brodiaei and Ulva lactuca. Mussels formed the dominant fouling organism between 6 and 20 m depth, below which were zones of Metridium senile and Alcyonium digitatum, serpulids and the deep water barnacle Balanus hameri. In September 1979 mussels exceeded 2500 m -2 with a modal length of 42 mm. By June 1981, modal length had increased to 67 mm at -4 m and 73 mm at -18 m (maximum size 97 mm). Populations on Bravo were similar. Comparison is made with growth rates on North Sea platforms. On Alpha, percentage cover m -2 in March 1980 was much greater at -4 m than at -18 m, but mean thickness was similar. At -18 m mussels were a heavier fouler on Bravo than Alpha. On Alpha mussel weight did not show a linear relationship with percentage cover.

  2. Standardization of the juvenile mussel bioassay: Dietary requirements

    SciTech Connect

    Warren, L.W.; Klaine, S.J.

    1995-12-31

    Optimizing a feeding regime is essential for establishing juvenile mussels (Utterbackia imbecillus) as a standard toxicity test organism. Although very little is known about their dietary requirements, these juveniles appear to derive adequate nourishment for survival and growth in batch culture from a diet of the green alga Chlorella vulgaris and Ankistrodesmus falcatus. However, results of previous studies have suggested that mussel diet in culture prior to exposure influences the sensitivity of these organisms to aqueous copper and cadmium exposure. Dietary components included three species of live algae (A. falcatus, C. vulgaris, and Scenedesmus quadricauda) and a suspension of rehydrated, dried Spirulina sp. Less than 24-hr laboratory cultured juveniles were fed all four components or combinations of three algal species daily to determine which mixtures promoted maximal growth. Preliminary data showed growth of control mussels receiving no food was comparable to those organisms fed all four algal species in combination. The greatest increase in shell length of juvenile mussels over 6 days was obtained with the tri-algal combination of A. falcatus, C. vulgaris, and S. quadricauda. The mixture resulting in the least growth included A. falcatus, S. quadricauda, and dried Spirulina sp.

  3. Byssal proteins of the freshwater zebra mussel, Dreissena polymorpha.

    PubMed

    Gantayet, Arpita; Ohana, Lily; Sone, Eli D

    2013-01-01

    The freshwater zebra mussel (Dreissena polymorpha) is a notorious biofouling organism. It adheres to a variety of substrata underwater by means of a proteinaceous structure called the byssus, which consists of a number of threads with adhesive plaques at the tips. The byssal proteins are difficult to characterize due to extensive cross-linking of 3,4-dihydroxyphenylalanine (DOPA), which renders the mature structure largely resistant to protein extraction and immunolocalization. By inducing secretion of fresh threads and plaques in which cross-linking is minimized, three novel zebra mussel byssal proteins were identified following extraction and separation by gel electrophoresis. Peptide fragment fingerprinting was used to match tryptic digests of several gel bands against a cDNA library of genes expressed uniquely in the mussel foot, the organ which secretes the byssus. This allowed identification of a more complete sequence of Dpfp2 (D. polymorpha foot protein 2), a known DOPA-containing byssal protein, and a partial sequence of Dpfp5, a novel protein with several typical characteristics of mussel adhesive proteins. PMID:23211030

  4. Mussel-inspired antifouling coatings bearing polymer loops.

    PubMed

    Li, Lin; Yan, Bin; Zhang, Ling; Tian, Yu; Zeng, Hongbo

    2015-11-11

    This work reports the preparation of antifouling coatings bearing polymer loops using a mussel-inspired ABA triblock copolymer using a simple drop coating method. With similar end graft density, the loop-bearing surfaces show a more enhanced protein-reduction performance than the brush-bearing surfaces. PMID:26364998

  5. Zebra mussel control using periodic chlorine dioxide treatments. Final report

    SciTech Connect

    Mussalli, Y.G.; Martin, P.D.

    1995-11-01

    Chlorine dioxide was injected into the water intakes at two power plants in Illinois and one in Indiana in an effort to eradicate the existing population of zebra mussels and mitigate further settlement in station river water cooling systems. Results of the treatments at Illinois Power Company`s Wood River Station on the Mississippi River, Central Illinois Public Service`s Meredosia Station on the Illinois River, and SI Energy`s Gallagher Station on the Ohio River are reported. Treatments were performed on a turnkey basis, with three treatments performed at Meredosia Station in 1994, six treatments performed at Wood River Station between July 1993 and September 1994, and 2 treatments performed at Gallagher Station in 1994. For each treatment, a contractor installed and operated a portable chlorine dioxide generator, monitored water quality and oxidant levels, and provided and monitored bioboxes containing test mussels. Results of the treatments were very favorable, indicating a good potential for periodic treatments with chlorine dioxide to control zebra mussel infestations in the raw water systems of power plants and other industrial facilities. Some difficulties with the chlorine dioxide generation system and cold temperature effects reduced the treatment effectiveness, particularly the second treatment at Gallagher Station. Average induced mortalities ranged from 70 to 100% at Wood River, 87 to 92% at Meredosia, and 30 to 100% at Gallagher for native mussels. Dechlorination successfully kept total oxidant residual levels at or below 0.05 ppM during all treatments at all stations.

  6. Zebra Mussel Monitoring and Control Guide. Final report

    SciTech Connect

    Not Available

    1992-12-01

    The Electric Power Research Institute (EPRI) Zebra Mussel Monitoring and Control Guide is a comprehensive compilation of US and European practices as reported in the open literature as of the end of 1992. EPRI considers the guide to be a living` document and will update it periodically in order to provide results of current research on chemical and nonchemical control technologies and utility experiences. The zebra mussel has infested all of the Great Lakes and other major rivers and waterways and is positioned to spread even more to the adjoining river basins. The impact of the zebra mussel on industrial power plantsis as a biofouler that clogs water systems and heat exchangers. This EPRI guideline identifies the zebra mussel, discusses its distribution in the United States, presents the potential threats to power plants, and presents the methods to initiate monitoring and control programs. Both preventive and corrective measures are presented. Preventive measures include various monitoring methods to initiate control techniques. The control techniques include both chemical and nonchemical together with combining techniques. Corrective methods include operational considerations, chemical cleaning, and mechanical/physical cleaning. It also may be possible to incorporate design changes, such as open to closed-loop backfit, backflushing, or pretreatment for closed systems. Various appendices are included that contain specifications to aid utilities in implementing several of the monitoring and control technologies, results of chemical evaluations at Cleveland Electric Illuminating Company plants, and data on the fate of various commercial molluscicides.

  7. Optimizing efficiency of zebra mussel monitoring at TVA power plants

    SciTech Connect

    Kerley, B.L.

    1995-06-01

    The Tennessee Valley Authority (TVA) began monitoring for zebra mussels in spring 1992 and first detected veligers entering plant intake at Shawnee, Allen and Cumberland Fossil Plans in summer 1993. Existing information indicated that densities of zebra mussel veligers at plant intakes did not always correspond to densities in critical pipe units; however, a more accurate predictive technique was unavailable. The two sites chosen for this project were Shawnee Fossil Plant on the Ohio River and Allen Fossil Plant on the Mississippi River. The project involved a coordinated series of experiments to determine how densities of zebra mussel veligers varied throughout the day, how veliger densities estimated outside the plants related to estimates at different internal locations, and how growth rate of adult zebra mussels compared using measurements taken inside and outside the plants and from the two different rivers. The data indicated no significant difference in veliger densities from samples collected at the intakes and samples collected inside the plants. There was also no significant difference in densities between samples collected inside the plants. There was also no significant difference in densities between samples taken at different times of the day. The data did indicate a significant difference in density estimates between samples collected on different days and between densities in the rivers compared to densities being drawn into the plant. The results will be used to assist plant staff in evaluating future data and in planning a more effective and cost efficient monitoring program.

  8. 75 FR 17758 - Approved Recovery Plan for the Scaleshell Mussel

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-04-07

    ... Fish and Wildlife Service Approved Recovery Plan for the Scaleshell Mussel AGENCY: Fish and Wildlife Service, Interior. ACTION: Notice of document availability. ] SUMMARY: We, the U.S. Fish and Wildlife... achieve removal of the species from the protections of the Endangered Species Act (Act). ADDRESSES:...

  9. 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...

  10. REGIONAL SUSCEPTIBILITY OF NORTHEAST LAKES TO ZEBRA MUSSEL INVASION

    EPA Science Inventory

    The rapid spread of the exotic zebra mussel (Dreissena polymorpha) concerns aquatic resource managers in the United States and Canada. ince 1990 it has been spreading from the Great Lakes into the Northeast. he primary goal of this study is to provide lake resource managers in th...

  11. A biomarker study using mussels deployed in San Diego Bay

    SciTech Connect

    Steinert, S.; Montee, R.S.; Chadwick, B.; Leather, J.; Sanders, B. Salazar, M.; Salazar, S.; Anderson, J.

    1995-12-31

    In the summer of 1995 a comprehensive assessment of the extent and consequences of marine environmental contamination in the area of Naval Station San diego was conducted. The study addressed contamination sources, distributions, concentrations, transport, sediment-water exchange, biological effects, and degradation. The biological effects portion of the study included contaminant bioaccumulation, growth, and biomarker measurements, in mussels deployed at six stations around the Naval Station. The mussels were deployed for {approximately} 30 days in plastic mesh bags, placed 1 meter above the bottom. To reduce variability the mussels for the study were initially sorted within an extremely narrow size range, 37.8 {+-} 0.6 mm. DNA damage as measured using the comet assay, and tissue levels of stress proteins hsp 60 and hsp 70, were the biomarkers measured. In addition, mussel tissue extracts were applied to the P450 (CYP1A1) reporter gene system. Stress related biological effects increased in relation to sediment contaminants at all but one station. Evidence from this study and an earlier 1993 study suggests that the non-sediment associated effects observed at one station may be the result of PAH photoactivation of accumulated PAHs.

  12. INVASIVE MUSSEL SPECIES AND THE INTEGRITY OF LARGE RIVERS

    EPA Science Inventory

    Presentation is a summary of patterns of invasion and ecological risk associated with invasive mussel species in Great Rivers. Data from EMAP-GRE are included. Findings of this study can inform expectations about where and what invasive species may colonize North American River...

  13. The zebra mussel: US utility implications. [Contains Glossary

    SciTech Connect

    McMahon, R.F. )

    1990-11-01

    Dreissena polymorpha, the freshwater macrofouling zebra mussel, was introduced to Lake St. Clair, near Detroit, Michigan, in 1985. It has since spread throughout Lake Erie. Its planktonic veliger larval stage disperses on water currents and adults are transported by human and natural vectors, making it likely to spread throughout most of the United States and southern Canada except for the southwestern and southern United State, where summer water temperatures are above tolerated levels. Veligers enter raw water systems on intake currents to settle and grow to adults attached by secreted byssal threads to hard surfaces. Accumulations of adults impede flow, aggravate sedimentation and corrosion, and foul small-diameter components. Settlement occurs at flow velocities less than 1.5--2.0 m/sec. Mussels can reduce effective pipe diameters and foul intake structures, steam condensers, heat exchangers, fire protection systems, and cooling tower basins. Establishment of mussels in raw water systems should be prevented because subsequent removal is difficult and expensive. Mitigation procedures include manual removal, robotic cleaning, thermal backwashing, water jetting, application of molluscicides, and possibly line pigging and acidic chemical cleaning. Control technologies include oxidizing and non-oxidizing molluscicides, robotic cleaning, shell strainers, exposure of veligers to high voltage electrical fields, thermal backwashing and sand-filtration. The United States power industry can utilize extensive European experience with this species and domestic experience with the Asian clam in its development of effective controls for zebra mussel fouling.

  14. Mogens Jansen: An Interview with a Danish Reading Educator.

    ERIC Educational Resources Information Center

    Engberg, Eva

    1985-01-01

    The president of the Danish Association of Reading Teachers discusses the positive effects of international cooperation on reading education, the influence of society's demands on curriculum, and the instinctive features and benefits of Danish Reading instruction. (FL)

  15. The Danish Collaborative Bacteraemia Network (DACOBAN) database

    PubMed Central

    Gradel, Kim Oren; Schønheyder, Henrik Carl; Arpi, Magnus; Knudsen, Jenny Dahl; Østergaard, Christian; Søgaard, Mette

    2014-01-01

    The Danish Collaborative Bacteraemia Network (DACOBAN) research database includes microbiological data obtained from positive blood cultures from a geographically and demographically well-defined population serviced by three clinical microbiology departments (1.7 million residents, 32% of the Danish population). The database also includes data on comorbidity from the Danish National Patient Registry, vital status from the Danish Civil Registration System, and clinical data on 31% of nonselected records in the database. Use of the unique civil registration number given to all Danish residents enables linkage to additional registries for specific research projects. The DACOBAN database is continuously updated, and it currently comprises 39,292 patients with 49,951 bacteremic episodes from 2000 through 2011. The database is part of an international network of population-based bacteremia registries from five developed countries on three continents. The main purpose of the DACOBAN database is to study surveillance, risk, and prognosis. Sex- and age-specific data on background populations enables the computation of incidence rates. In addition, the high number of patients facilitates studies of rare microorganisms. Thus far, studies on Staphylococcus aureus, enterococci, computer algorithms for the classification of bacteremic episodes, and prognosis and risk in relation to socioeconomic factors have been published. PMID:25258557

  16. 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.

  17. The Danish Communicative Developmental Inventories: Validity and Main Developmental Trends

    ERIC Educational Resources Information Center

    Bleses, Dorthe; Vach, Werner; Slott, Malene; Wehberg, Sonja; Thomsen, Pia; Madsen, Thomas O.; Basboll, Hans

    2008-01-01

    This paper presents a large-scale cross-sectional study of Danish children's early language acquisition based on the Danish adaptation of the "MacArthur-Bates Communicative Development Inventories" (CDI). Measures of validity and reliability imply that the Danish adaptation of the American CDI has been adjusted linguistically and culturally in…

  18. The Blue Marble

    NASA Technical Reports Server (NTRS)

    2002-01-01

    This spectacular Moderate Resolution Imaging Spectroradiometer (MODIS) 'blue marble' image is based on the most detailed collection of true-color imagery of the entire Earth to date. Using a collection of satellite-based observations, scientists and visualizers stitched together months of observations of the land surface, oceans, sea ice, and clouds into a seamless, true-color mosaic of every square kilometer (.386 square mile) of our planet. Most of the information contained in this image came from MODIS, illustrating MODIS' outstanding capacity to act as an integrated tool for observing a variety of terrestrial, oceanic, and atmospheric features of the Earth. The land and coastal ocean portions of this image is based on surface observations collected from June through September 2001 and combined, or composited, every eight days to compensate for clouds that might block the satellite's view on any single day. Global ocean color (or chlorophyll) data was used to simulate the ocean surface. MODIS doesn't measure 3-D features of the Earth, so the surface observations were draped over topographic data provided by the U.S. Geological Survey EROS Data Center. MODIS observations of polar sea ice were combined with observations of Antarctica made by the National Oceanic and Atmospheric Administration's AVHRR sensor-the Advanced Very High Resolution Radiometer. The cloud image is a composite of two days of MODIS imagery collected in visible light wavelengths and a third day of thermal infra-red imagery over the poles. A large collection of imagery based on the blue marble in a variety of sizes and formats, including animations and the full (1 km) resolution imagery, is available at the Blue Marble page. Image by Reto Stockli, Render by Robert Simmon. Based on data from the MODIS Science Team

  19. Accumulation, elimination, and speciation of cadmium and zinc in mussels, Mytilus edulis, in the natural environment

    SciTech Connect

    Luten, J.B.; Bouquet, W.; Burggraaf, M.M.; Rus, J.

    1986-10-01

    Accumulation of trace metals like cadmium and zinc by the common mussel (Mytilus edulis) has been often studied. Most of these studies have been carried out under laboratory conditions. It has been shown that the accumulation of cadmium by the common mussel is affected by abiotic factors like salinity, temperature and the presence of complexing agents and biotic factors like animal size, sex and maturity. Elimination studies of cadmium from the common mussel are scarce. Detoxification of cadmium by the common mussel takes place by binding to low (metallothionein) and high molecular weight proteins. The objective of this study was to investigate accumulation and elimination of cadmium and zinc by the common mussel in the natural environment in combination with a study about the speciation of cadmium and zinc in the common mussel.

  20. Moderate establishment success of Pacific oyster, Crassostrea gigas, on a sheltered intertidal mussel bed

    NASA Astrophysics Data System (ADS)

    Holm, Mark Wejlemann; Davids, Jens Kristian; Dolmer, Per; Vismann, Bent; Hansen, Benni Winding

    2015-10-01

    The Pacific oyster (Crassostrea gigas Thunberg 1793) is introduced into marine ecosystems worldwide. In Denmark, C. gigas was introduced into the micro tidal Limfjord, around 1972 for aquaculture. This study describes the population structure of C. gigas at Agger Tange in 2007, 2009, 2010 and 2011. Here, C. gigas use beds of Blue mussels (Mytilus edulis L.) as primary habitat. The mean abundance (± 1 SD) of C. gigas was unchanged during our study (45 ± 2 indv. m- 2), while it increased for M. edulis from 2010 to 2011 (934 ± 610 to 1434 ± 750 indv. m- 2, respectively). In 2009, a newly settled cohort of C. gigas was present, but in the succeeding years no or negligible recruitment was recorded. However, age cohort analyses, based on individual shell size at different ages, suggest successful recruitment in three out of seven years. A comparison with the course of the bioinvasion in List Tidal Basin, suggests that the population at Agger Tange is not in the expansion phase of the bioinvasion, despite of frequent settlement, high shell growth rates and relatively high abundance. So far, C. gigas has had moderate establishment success. We conclude that C. gigas is still in the establishment phase, but that this is prolonged, presumably due to low food availability.

  1. 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.

  2. IMPACT OF SIPHONING ACTIVITY AND NATURALLY SUSPENDED PARTICLE LOAD ON MUSSEL KILL by PSEUDOMONAS FLUORESCENS

    SciTech Connect

    Daniel Molloy

    2003-08-04

    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 into 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.

  3. Estimation of Mussel Population Response to Hydrologic Alteration in a Southeastern U.S. Stream

    NASA Astrophysics Data System (ADS)

    Peterson, James T.; Wisniewski, Jason M.; Shea, Colin P.; Rhett Jackson, C.

    2011-07-01

    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

  4. 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.

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

    PubMed

    Peterson, James T; Wisniewski, Jason M; Shea, Colin P; Jackson, C Rhett

    2011-07-01

    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

  6. Proceedings of the fifth international zebra mussel and other aquatic nuisance organisms conference 1995

    SciTech Connect

    Ackerman, J.D.

    1995-06-01

    This report contains articles from the proceedings of the fifth international zebra mussel & other aquatic nuisance organisms conference. Topics include articles on: Zebra mussel life history; Strategies for application of non-oxidizing biocides; examination of the potential of chlorine dioxide for use in zebra mussel veliger control; and ballast water control; overview of the Canadian approach. Selected papers are indexed separately for inclusion in the Energy Science and Technology Database.

  7. Sea Otters Homogenize Mussel Beds and Reduce Habitat Provisioning in a Rocky Intertidal Ecosystem

    PubMed Central

    Singh, Gerald G.; Markel, Russell W.; Martone, Rebecca G.; Salomon, Anne K.; Harley, Christopher D. G.; Chan, Kai M. A.

    2013-01-01

    Sea otters (Enhydra lutris) are keystone predators that consume a variety of benthic invertebrates, including the intertidal mussel, Mytilus californianus. By virtue of their competitive dominance, large size, and longevity, M. californianus are ecosystem engineers that form structurally complex beds that provide habitat for diverse invertebrate communities. We investigated whether otters affect mussel bed characteristics (i.e. mussel length distributions, mussel bed depth, and biomass) and associated community structure (i.e. biomass, alpha and beta diversity) by comparing four regions that varied in their histories of sea otter occupancy on the west coast of British Columbia and northern Washington. Mussel bed depth and average mussel lengths were 1.5 times lower in regions occupied by otters for >20 years than those occupied for <5 yrs. Diversity of mussel bed associated communities did not differ between regions; however, the total biomass of species associated with mussel beds was more than three-times higher where sea otters were absent. We examined alternative explanations for differences in mussel bed community structure, including among-region variation in oceanographic conditions and abundance of the predatory sea star Pisaster ochraceus. We cannot discount multiple drivers shaping mussel beds, but our findings indicate the sea otters are an important one. We conclude that, similar to their effects on subtidal benthic invertebrates, sea otters reduce the size distributions of intertidal mussels and, thereby, habitat available to support associated communities. Our study indicates that by reducing populations of habitat-providing intertidal mussels, sea otters may have substantial indirect effects on associated communities. PMID:23717697

  8. Assessment of freshwater mussels in the Allegheny River at Foxburg, Pennsylvania, 1998

    USGS Publications Warehouse

    Anderson, Robert M.

    2000-01-01

    The upper reaches of the Allegheny River are a high-quality resource that supports populations of a number of endangered species. Two endangered species of freshwater mussel, the northern riffleshell, Epioblasma torulosa rangiana, and clubshell, Pleurobema clava, are present in this river reach. Prior to a bridge-replacement project at the Allegheny River at Foxburg, Pa. (river mile 86.2), a mussel survey was conducted to determine if either of the protected endangered species are present and to assess the quality of the mussel bed at this site. Shore and near-shore searches followed by SCUBA diving transects determined that a mussel bed is present at this location. The freshwater-mussel community consists of at least 14 species and includes both endangered species. Substrate type, stream velocity, and channel morphology combined with results from the transect searches documented that the mussel bed is largely limited to the east side of the river. A two-stage sampling design was employed to estimate the overall mussel abundance within the bed. Twelve 4-m2 (square meter) cells were sampled with four 0.25-m2 quadrants per cell. The mean population density within the mussel bed is 8.4 mussel per square meter. The overall mussel population in the survey area is 225,567 individuals (95-percent confidence interval, 135,973 to 374,195). River-bed scour and acid mine drainage appear to limit mussel distribution in the center and left section of the channel. Overall, a healthy and diverse mussel bed exists at this site.

  9. 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

  10. Recruitment of shore crabs Carcinus maenas on tidal flats: Mussel clumps as an important refuge for juveniles

    NASA Astrophysics Data System (ADS)

    Thiel, M.; Dernedde, T.

    1994-06-01

    During the late summer and early fall, juvenile shore crabs ( Carcinus maenas L.) occurred in high abundances in mussel clumps scattered on tidal flats of the Wadden Sea. Abundances were much lower on bare tidal flats without mussel clumps and decreased substantially from July to November, whereas numbers in mussel clumps remained high. Large crabs left the tidal flats in early fall, whereas juveniles undertook tidal migrations only in the late fall. In March very few shore crabs were found in the intertidal area. The size of juvenile shore crabs living between mussels did not increase significantly during fall. On the bare tidal flats surrounding the mussels, a size increase was observed. Mussel beds and mussel clumps serve as a spatial refuge for the early benthic phases of juvenile shore crabs. Between mussels they can hide effectively from their epibenthic predators. Juvenile shore crabs do not leave the intertidal area and the mussel habitats before their major predators have left the area. Mussel clumps scattered over the tidal flats may be a critical refuge for juvenile shore crabs settling on tidal flats. Intensified efforts in mussel culturing in the European Wadden Sea during recent decades may have caused an increased abundance of mussel clumps on tidal flats, thus enhancing habitat availability for some mussel-clump inhabitants.

  11. Blue ocean leadership.

    PubMed

    Kim, W Chan; Mauborgne, Renée

    2014-05-01

    Ten years ago, two INSEAD professors broke ground by introducing "blue ocean strategy," a new model for discovering uncontested markets that are ripe for growth. In this article, they apply their concepts and tools to what is perhaps the greatest challenge of leadership: closing the gulf between the potential and the realized talent and energy of employees. Research indicates that this gulf is vast: According to Gallup, 70% of workers are disengaged from their jobs. If companies could find a way to convert them into engaged employees, the results could be transformative. The trouble is, managers lack a clear understanding of what changes they could make to bring out the best in everyone. Here, Kim and Mauborgne offer a solution to that problem: a systematic approach to uncovering, at each level of the organization, which leadership acts and activities will inspire employees to give their all, and a process for getting managers throughout the company to start doing them. Blue ocean leadership works because the managers' "customers"-that is, the people managers oversee and report to-are involved in identifying what's effective and what isn't. Moreover, the approach doesn't require leaders to alter who they are, just to undertake a different set of tasks. And that kind of change is much easier to implement and track than changes to values and mind-sets. PMID:24956870

  12. Blue emitting undecaplatinum clusters

    NASA Astrophysics Data System (ADS)

    Chakraborty, Indranath; Bhuin, Radha Gobinda; Bhat, Shridevi; Pradeep, T.

    2014-07-01

    A blue luminescent 11-atom platinum cluster showing step-like optical features and the absence of plasmon absorption was synthesized. The cluster was purified using high performance liquid chromatography (HPLC). Electrospray ionization (ESI) and matrix assisted laser desorption ionization (MALDI) mass spectrometry (MS) suggest a composition, Pt11(BBS)8, which was confirmed by a range of other experimental tools. The cluster is highly stable and compatible with many organic solvents.A blue luminescent 11-atom platinum cluster showing step-like optical features and the absence of plasmon absorption was synthesized. The cluster was purified using high performance liquid chromatography (HPLC). Electrospray ionization (ESI) and matrix assisted laser desorption ionization (MALDI) mass spectrometry (MS) suggest a composition, Pt11(BBS)8, which was confirmed by a range of other experimental tools. The cluster is highly stable and compatible with many organic solvents. Electronic supplementary information (ESI) available: Details of experimental procedures, instrumentation, chromatogram of the crude cluster; SEM/EDAX, DLS, PXRD, TEM, FT-IR, and XPS of the isolated Pt11 cluster; UV/Vis, MALDI MS and SEM/EDAX of isolated 2 and 3; and 195Pt NMR of the K2PtCl6 standard. See DOI: 10.1039/c4nr02778g

  13. 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.

  14. 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.

  15. Biomarker responses in mussels, an integrated approach to biological effects measurements.

    PubMed

    Brooks, Steven; Lyons, Brett; Goodsir, Freya; Bignell, John; Thain, John

    2009-01-01

    Biological effects techniques have been used with the aim to further integrate biological effects measurements with chemical analysis and apply these methods to provide an assessment of mussel health status. Live native mussels were collected from selected coastal and estuarine sites around the British Isles, including the rivers Test, Thames, Tees, and Clyde, and Lunderston Bay. A suite of biological effects techniques was undertaken on these mussels, including whole organism responses (scope for growth), tissue responses (histopathology), and subcellular responses (lysosomal stability, multi-xenobiotic resistance [MXR], and Comet assay). In addition, whole mussel homogenates were used to measure organic (polycyclic aromatic hydrocarbons [PAH], polychlorinated biphenyls [PCB]) and metal concentrations. Overall the mussels collected from the Thames were in relatively poor health, based on histopathological markers, significantly higher DNA damage, and elevated expression of MXR detoxifying proteins. In contrast, the mussels collected from the River Test were in the best health, based on histopathological markers, respiration rate (SFG), and low frequency of DNA damage. In conclusion, the biological effects techniques were able to distinguish between relatively contaminated and clean environments, with the Thames mussels in worst health. Mussel tissue chemistry data were not able to explain the variations in biological response. Evidence indicates that the difference in the health of the mussels between the different sites was due to either effects of contaminants that were not measured, or the combined effects of mixture toxicity resulting in a threshold effect. PMID:19184734

  16. Mussels as ecosystem engineers: Their contribution to species richness in a rocky littoral community

    NASA Astrophysics Data System (ADS)

    Borthagaray, Ana Inés; Carranza, Alvar

    Mussels are important ecosystem engineers in marine benthic systems because they aggregate into beds, thus modifying the nature and complexity of the substrate. In this study, we evaluated the contribution of mussels ( Brachidontes rodriguezii, Mytilus edulis platensis, and Perna perna) to the benthic species richness of intertidal and shallow subtidal communities at Cerro Verde (Uruguay). We compared the richness of macro-benthic species between mussel-engineered patches and patches without mussels but dominated by algae or barnacles at a landscape scale (all samples), between tidal levels, and between sites distributed along a wave exposition gradient. Overall, we found a net increase in species richness in samples with mussels (35 species), in contrast to samples where mussels were naturally absent or scarce (27 species). The positive trend of the effect did not depend upon tidal level or wave exposition, but its magnitude varied between sites. Within sites, a significant positive effect was detected only at the protected site. Within the mussel-engineered patches, the richness of all macro-faunal groups (total, sessile and mobile) was positively correlated with mussel abundance. This evidence indicates that the mussel beds studied here were important in maintaining species richness at the landscape-level, and highlights that beds of shelled bivalves should not be neglected as conservation targets in marine benthic environments.

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

    USGS Publications Warehouse

    Cope, W.G.; Waller, D.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.

  18. 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. PMID:27003262

  19. Clearance Rate of the Mussel Anodonta Californiensis Exposed to Nannochloropsis Algae

    NASA Astrophysics Data System (ADS)

    Castañeda, G. R.; Luthy, R. G.; Ismail, N.

    2012-12-01

    Bivalves such as mussels and clams are filter feeding organisms that can be utilized to remove particulate matter from water. The native mussel species Anodonta californiensis is being studied for use as a potential natural treatment mechanism to filter water within treatment wetlands. Quantifying the ability of these mussels to remove particulate matter is important information necessary to understand their potential to purify water. Results from clearance rate experiments will be discussed. Information obtained from these clearance rate experiments can potentially be extrapolated to understand the capability of mussels to remove other particulate matter or contaminants.

  20. Effects of substrate and hydrodynamic conditions on the formation of mussel beds in a large river

    USGS Publications Warehouse

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

    2006-01-01

    A numerical model for simulation of freshwater mussel dynamics was used to investigate the effects of substrate and hydrodynamic conditions on the formation of mussel beds in a 10-km reach of the Upper Mississippi River (UMR). Suitable habitats for mussel survival were identified by creating a dimensionless parameter (shear stress ratio) combining shear force and substrate type. This parameter is a measure of substrate stability that could be used in many different applications. Dispersal of juvenile mussels with flow as they detach from their fish hosts was simulated by a particle-tracking mechanism that identified suitable areas for colonization with the potential to evolve into mussel beds. Simulated areas of mussel accumulation coincided with reported locations of mussel beds, and simulated densities were in the range of abundant mussel beds in other reaches of the UMR. These results, although more qualitative than quantitative, provide insight into factors influencing the formation of mussel beds in a large river. ?? 2006 by The North American Benthological Society.

  1. 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

  2. Bioaccumulation of PAHs in the zebra mussel, Dreissena polymorpha, at Times Beach, New York

    SciTech Connect

    Roper, J.M. |; Cherry, D.S.; Simmers, J.W.

    1994-12-31

    While zebra mussels have not been reported in confined disposal facilities (CDFs), recent reports of zebra mussels in soft sediments indicate a possible concern for dredging and the disposal of dredged material. In response to this concern, an insitu biomonitoring study utilizing the zebra mussel was performed at the Times Beach CDF, in Buffalo, NY. Mussels were placed at the facility for 30 days at sites of known PAH concentrations. The placement occurred at areas of comparably high, intermediate and low total PAH sediment concentrations. At each site the mussels were placed both in the water column and at the sediment surface. Mussels were collected on Day 34 of the study for tissue analysis. Tissues concentrations of total PAHs from mussels placed in water column and the sediment respectively were at the high site 8.4 and 5.6 mg/Kg, the intermediate site 4.3 and 3.3 mg/Kg and low site 3.2 and 2.7 mg/Kg. The following issues will be addressed; PAH concentration in the tissues compared to site sediment concentrations and the accumulation differences of mussels placed in the water column versus those in the sediment. The data indicate that zebra mussel PAH bioaccumulation potential is of environmental concern.

  3. 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

  4. Conditions for coexistence of freshwater mussel species via partitioning of fish host resources

    USGS Publications Warehouse

    Rashleigh, B.; DeAngelis, D.L.

    2007-01-01

    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 larval stage may promote coexistence. A model of resource utilization was developed for two mussel species and analyzed to determine conditions for coexistence. Mussel species were predicted to coexist when they differed in terms of their success in contacting different fish host species; very similar strategies offered limited possibilities for coexistence. Differences in the mussel species' maximum infestation loads on the fish hosts that coincided with differences in their fish host contact success promoted coexistence. Mussel species with a given set of trade-offs in fish host use were predicted to coexist only for a subset of relative fish host abundances, so a shift in relative fish host abundances could result in the loss of a mussel species. An understanding of the conditions for freshwater mussel species coexistence can help explain high mussel diversity in rivers and guide ongoing conservation activities. ?? 2006 Elsevier B.V. All rights reserved.

  5. Removal of algae by the zebra mussel (Dreissena polymorpha) population in western Lake Erie: a bioenergetics approach

    USGS Publications Warehouse

    Madenjian, Charles P.

    1995-01-01

    A bioenergetics model for growth of a zebra mussel (Dreissena polymorpha) individual was verified with observations on zebra mussel growth in western Lake Erie. The bioenergetics model was then applied to the zebra mussel population in the western basin of Lake Erie to estimate the removal of phytoplankton by mussels. According to the modeling results, the zebra mussel population consumed 5.0 million tonnes of phytoplankton, while 1.4 million tonnes of phytoplankton was deposited in pseudofeces from the mussels. Thus, a total of 6.4 ± 2.4 million tonnes of phytoplankton was removed from the water column by zebra mussel in western Lake Erie during 1990. Primary production was estimated to be 24.8 million tonnes; therefore, zebra mussel removed the equivalent of 26 ± 10% of the primary production for western Lake Erie.

  6. Selective settlement of the barnacle Semibalanus balanoides (L.) facilitates its growth and reproduction on mussel beds in the Wadden Sea

    NASA Astrophysics Data System (ADS)

    Buschbaum, Christian

    2001-07-01

    On the unstable sedimentary tidal flats of the Wadden Sea, a suitable attachment substrate for sessile organisms is generally lacking. Epibenthic mussel beds (Mytilus edulis L.) provide the only and strongly limited settlement sites available for the barnacle, Semibalanus balanoides (L.). Field investigations showed that barnacles were non-randomly distributed within a mussel bed. They preferentially occurred near the siphonal apertures of living mussels but rarely grew on dead mussels or shell fragments. Field experiments revealed that this was due to selective settlement of barnacle cyprid larvae. Growth of barnacles was significantly higher upon living mussels than on empty mussel shells. Moreover, a higher reproductive output was obtained by individuals on living mussels which produced twice as many nauplii larvae than barnacles attached to empty shells. This study shows that selective settlement of S. balanoides cyprid larvae on living mussels is adaptive with respect to individual fitness.

  7. Habitat engineering by the invasive zebra mussel Dreissena polymorpha (Pallas) in a boreal coastal lagoon: impact on biodiversity

    NASA Astrophysics Data System (ADS)

    Zaiko, Anastasija; Daunys, Darius; Olenin, Sergej

    2009-03-01

    Habitat engineering role of the invasive zebra mussel Dreissena polymorpha (Pallas) was studied in the Curonian lagoon, a shallow water body in the SE Baltic. Impacts of live zebra mussel clumps and its shell deposits on benthic biodiversity were differentiated and referred to unmodified (bare) sediments. Zebra mussel bed was distinguished from other habitat types by higher benthic invertebrate biomass, abundance, and species richness. The impact of live mussels on biodiversity was more pronounced than the effect of shell deposits. The structure of macrofaunal community in the habitats with >103 g/m2 of shell deposits devoid of live mussels was similar to that found within the zebra mussel bed. There was a continuous shift in species composition and abundance along the gradient ‘bare sediments—shell deposits—zebra mussel bed’. The engineering impact of zebra mussel on the benthic community became apparent both in individual patches and landscape-level analyses.

  8. Trend Analyses of Nitrate in Danish Groundwater

    NASA Astrophysics Data System (ADS)

    Hansen, B.; Thorling, L.; Dalgaard, T.; Erlandsen, M.

    2012-04-01

    This presentation assesses the long-term development in the oxic groundwater nitrate concentration and nitrogen (N) loss due to intensive farming in Denmark. Firstly, up to 20-year time-series from the national groundwater monitoring network enable a statistically systematic analysis of distribution, trends and trend reversals in the groundwater nitrate concentration. Secondly, knowledge about the N surplus in Danish agriculture since 1950 is used as an indicator of the potential loss of N. Thirdly, groundwater recharge CFC (Chlorofluorocarbon) age determination allows linking of the first two dataset. The development in the nitrate concentration of oxic groundwater clearly mirrors the development in the national agricultural N surplus, and a corresponding trend reversal is found in groundwater. Regulation and technical improvements in the intensive farming in Denmark have succeeded in decreasing the N surplus by 40% since the mid 1980s while at the same time maintaining crop yields and increasing the animal production of especially pigs. Trend analyses prove that the youngest (0-15 years old) oxic groundwater shows more pronounced significant downward nitrate trends (44%) than the oldest (25-50 years old) oxic groundwater (9%). This amounts to clear evidence of the effect of reduced nitrate leaching on groundwater nitrate concentrations in Denmark. Are the Danish groundwater monitoring strategy obtimal for detection of nitrate trends? Will the nitrate concentrations in Danish groundwater continue to decrease or are the Danish nitrate concentration levels now appropriate according to the Water Framework Directive?

  9. Escherichia vulneris in a Danish soccer wound.

    PubMed

    Jepsen, C F; Klebe, T M; Prag, J

    1997-01-01

    Escherichia vulneris was isolated from an infected soccer wound, a finding which has not apparently been described in Europe before, but by questioning Danish clinical microbiological laboratories a further 12 cases were discovered. Treatment with simple debridement and cefuroxime quickly eradicated the bacteria in our case. PMID:9255899

  10. Evaluating University Continuing Education: A Danish Case.

    ERIC Educational Resources Information Center

    Thune, Christian

    2002-01-01

    The Danish Evaluation Institute is conducting systematic assessments of three master's programs in public administration, public policy, and public management. They have found that explicit criteria have advantages and disadvantages. Development of criteria attempts to meet the following demands: uniformity, relevance of level, scope, precision,…

  11. Care and Education in the Danish Creche

    ERIC Educational Resources Information Center

    Brostrom, Stig; Hansen, Ole Henrik

    2010-01-01

    This article seeks to identify the relation between policy and lived life, for the small child in the Danish creche. To accomplish this, the article integrates demography, traditions, national curriculum and psychological, educational, and recent developments in research. It is an attempt to reveal knowledge and consequences, by conducting the…

  12. The Danish Free School Tradition under Pressure

    ERIC Educational Resources Information Center

    Olsen, Tore Vincents

    2015-01-01

    The Danish free school tradition has entailed a large degree of associational freedom for non-governmental schools, religious as well as non-religious. Until the late 1990s, the non-governmental schools were under no strict ideological or pedagogical limitations; they could recruit teachers and students according to their own value base, and were…

  13. Mussel foot protein-1 (mcfp-1) interaction with titania surfaces†

    PubMed Central

    Harrington, Matthew J.; Lu, Qingye; Masic, Admir

    2012-01-01

    Marine mussels utilize a variety of DOPA-rich proteins for purposes of underwater adhesion, as well as for creating hard and flexible surface coatings for their tough and stretchy byssal fibers. In the present study, moderately strong, yet reversible wet adhesion between the protective mussel coating protein, mcfp-1, and amorphous titania was measured with a surface force apparatus (SFA). In parallel, resonance Raman spectroscopy was employed to identify the presence of bidentate DOPA–Ti coordination bonds at the TiO2–protein interface, suggesting that catechol–TiO2 complexation contributes to the observed reversible wet adhesion. These results have important implications for the design of protective coatings on TiO2. PMID:23100857

  14. Metals and PCB concentrations in mussels from Long Island Sound

    SciTech Connect

    Greig, R.A.; Sennefelder, G.

    1985-09-01

    Metals and polychlorinated biphenyls (PCBs) are contaminants of concern in Long Island Sound. To gain an understanding of contaminant inputs from the major rivers of Connecticut into the Sound, a continuous measurement over time should be made of the concentrations of contaminants in the river water. Analyses of water for contaminants are quite complex and often ambiguous because of the dynamic nature of river water. To alleviate this problem, the mussel, Mytilus edulis, has been proposed by various researchers to be a good subject for monitoring contaminants present in the water column. For this study, mussels were collected from the mouths of various rivers and inshore areas along the Connecticut shoreline and analyzed for cadmium, copper, and PCBs.

  15. Electric utility Zebra Mussel Control technology conference: Proceedings

    SciTech Connect

    Tsou, J.L. ); Mussalli, Y.G. )

    1992-03-01

    This Conference on Zebra Mussel Control technology was held on October 22--23, 1991 in Itasca (Chicago), Illinois. The Conference was sponsored by EPRI Zebra Mussel Task Force and hosted by Commonwealth Edison Company to bring together representatives of utilities, manufacturers, researches, and consultants. Nineteen papers were presented in three sessions. These sessions were devoted to the following topics: Overview and Control Strategy, Monitoring and Non-Chemical Control Technology, and Chemical Control Technology. A half-day workshop/panel discussion devoted to the same topics was conducted at the second day of the formal presentations. More than 160 people attended this Conference. This report contains technical papers and summaries of the workshop/panel sessions. Of these 19 papers, there are 4 papers related to overview and control strategy, 7 papers related to monitoring and non-chemical control technology, and 8 papers related to chemical control technology.

  16. Liquid Chromatographic Determination of Amnesic Shellfish Poison in Mussels

    NASA Astrophysics Data System (ADS)

    Duxbury, Mark

    2000-10-01

    A simple, rapid, high-performance liquid chromatographic experiment suitable for undergraduate students is described for determining amnesic shellfish poison in mussels. The poison itself is an unusual naturally occurring amino acid, domoic acid, that has been found in seafood, particularly shellfish, worldwide. The symptoms of poisoning include amnesia (memory loss), loss of balance, mental confusion, nausea, vomiting, diarrhea, coma, and in extreme cases death. The domoic acid is extracted from homogenized mussel tissue by boiling in water for 5 minutes. The homogenate is cooled and centrifuged, and an aliquot of the supernatant is diluted and analyzed by isocratic HPLC using a C18 column and an acetonitrile-water mobile phase at pH 2.5 with UV detection at 242 nm.

  17. Determination of Polonium-210 in Mussels from the Adria Sea

    NASA Astrophysics Data System (ADS)

    Bylyku, Elida; Bode, Kozeta; Fisnka, Kujtim; Cfarku, Florinda

    2010-01-01

    The important role played by alpha radioactive nuclides in the marine radiation environment is already evident. The dominant contribution made by natural fall-out nuclide Polonium-210 to the alpha radioactivity of most marine organisms is very important. The common mussel Mytilus galloprovincialis is selected as unique bio monitor species to be analyzed. Samples are collected at the Adria Sea along the Albanian coast. A radiochemical procedure followed by alpha spectrometry measurement of 210Po is performed. The standard solution of 209Po is used as a yield tracer. Thin sources for alpha spectrometry measurements are prepared by spontaneous deposition of polonium on to silver disks from weakly acid solutions. The value of specific activity of 210Po vary between 200 to 400 Bq/kg dry and are in good agreement with the results found for 210Po in mussels from other countries in the Adria Sea.

  18. The air quality in Danish urban areas.

    PubMed

    Jensen, F P; Fenger, J

    1994-10-01

    The Danish air pollution abatement is based by and large on emission control. Since the ratification of the international sulfur protocol of 1985, there has been a continuous tightening of the permissible sulfur content in fuels and of the maximum emissions from power plants. As a consequence, the total annual emission of sulfur dioxide (SO2) has been reduced from 450,000 tons in the seventies to 180,000 tons in 1990. This has had a pronounced effect on the SO2 levels in Danish urban areas. Thus, in Copenhagen, the yearly averages have fallen to about 25%. For nitrogen oxides emitted from the power plants, similar regulations are in force. With this legislation, the most important and crucial source of air pollution in Danish urban areas is road traffic. The contribution of nitrogen oxides from national traffic accounts for nearly half the total Danish emission and is increasing steadily; this is consistent with an observed increase of nitrogen oxides in ambient air. The permissible levels of lead in petrol has been reduced drastically. After an introduction of reduced tax on lead-free petrol, it now accounts for more than two-thirds of the total consumption. As a result, the concentration of lead in urban ambient air has been reduced to less than one-sixth. The introduction of 3-way catalytic converters from October 1990 will result in reductions in the emission of a series of pollutants, e.g., lead, volatile organic compounds, carbon monoxide, and nitrogen oxides. In 1980, a Danish air quality monitoring program was established as a cooperative effort between the authorities, the Government, the countries, the municipalities, and the Greater Copenhagen Council.(ABSTRACT TRUNCATED AT 250 WORDS) PMID:7821296

  19. A shell regeneration assay to identify biomineralization candidate genes in mytilid mussels.

    PubMed

    Hüning, Anne K; Lange, Skadi M; Ramesh, Kirti; Jacob, Dorrit E; Jackson, Daniel J; Panknin, Ulrike; Gutowska, Magdalena A; Philipp, Eva E R; Rosenstiel, Philip; Lucassen, Magnus; Melzner, Frank

    2016-06-01

    Biomineralization processes in bivalve molluscs are still poorly understood. Here we provide an analysis of specifically expressed sequences from a mantle transcriptome of the blue mussel, Mytilus edulis. We then developed a novel, integrative shell injury assay to test, whether biomineralization candidate genes highly expressed in marginal and pallial mantle could be induced in central mantle tissue underlying the damaged shell areas. This experimental approach makes it possible to identify gene products that control the chemical micro-environment during calcification as well as organic matrix components. This is unlike existing methodological approaches that work retroactively to characterize calcification relevant molecules and are just able to examine organic matrix components that are present in completed shells. In our assay an orthogonal array of nine 1mm holes was drilled into the left valve, and mussels were suspended in net cages for 20, 29 and 36days to regenerate. Structural observations using stereo-microscopy, SEM and Raman spectroscopy revealed organic sheet synthesis (day 20) as the first step of shell-repair followed by the deposition of calcite crystals (days 20 and 29) and aragonite tablets (day 36). The regeneration period was characterized by time-dependent shifts in gene expression in left central mantle tissue underlying the injured shell, (i) increased expression of two tyrosinase isoforms (TYR3: 29-fold and TYR6: 5-fold) at day 20 with a decline thereafter, (ii) an increase in expression of a gene encoding a nacrein-like protein (max. 100-fold) on day 29. The expression of an acidic Asp-Ser-rich protein was enhanced during the entire regeneration process. This proof-of-principle study demonstrates that genes that are specifically expressed in pallial and marginal mantle tissue can be induced (4 out of 10 genes) in central mantle following experimental injury of the overlying shell. Our findings suggest that regeneration assays can be used

  20. Pluto’s Blue Haze

    NASA Video Gallery

    The sky on Pluto is blue! Kind of. This is Pluto in an Minute. So it’s not exactly the case that the sky on Pluto is blue, rather, what the New Horizons science team has found in recent images do...

  1. Hydrological Controls on Water Chemistry that Supports Freshwater Mussel Populations

    NASA Astrophysics Data System (ADS)

    Prestegaard, K. L.

    2012-12-01

    Native freshwater mussel species ranges and population sizes have been declining throughout N. America. Due to their sedentary nature, adult mussels are vulnerable to both local habitat changes (often associated with land-use changes, contaminants, and biological invaders) and to climate changes that can alter river flow regimes, bed stability, and water chemistry. The purpose of this study is to examine the relationship between water chemistry and hydrological events in rivers that support native mussel populations. USGS ion concentration and water quality (pH, temperature, conductivity) data were used to calculate saturation indices for aragonite. For some sites, electrical conductivity was highly correlated with calcium and bicarbonate concentrations and could be used to estimate concentrations when ion chemistry was not measured. Continuous water quality data from datasondes could thus be used to evaluate saturation indices for aragonite on a daily basis for 10-15 year periods. For the Delaware River, which has relatively few carbonate rocks in its watershed, tributary aragonite saturation tended to reflect local geological conditions. The lower main stem of the river integrates the water chemistry of the basin and also responds to climatic conditions. The lower Delaware supports aragonite precipitation approximately 50 days per year, with considerable inter-annual variability. During most years, aragonite precipitation could occur during both the spring and late summer periods, but years with heavy spring rains rather than snowmelt shifts aragonite precipitation to late summer periods. In 2011 when several major tropical storms hit the Delaware basin, streamflow was too dilute for aragonite precipitation for most of the summer period. These data suggest that hydrological changes associated with climatic changes may influence the water chemistry and affect the suitability of some rivers as mussel habitat.

  2. Ammonia excretion in mytilid mussels is facilitated by ciliary beating.

    PubMed

    Thomsen, J; Himmerkus, N; Holland, N; Sartoris, F J; Bleich, M; Tresguerres, M

    2016-08-01

    The excretion of nitrogenous waste products in the form of ammonia (NH3) and ammonium (NH4 (+)) is a fundamental process in aquatic organisms. For mytilid bivalves, little is known about the mechanisms and sites of excretion. This study investigated the localization and the mechanisms of ammonia excretion in mytilid mussels. An Rh protein was found to be abundantly expressed in the apical cell membrane of the plicate organ, which was previously described as a solely respiratory organ. The Rh protein was also expressed in the gill, although at significantly lower concentrations, but was not detectable in mussel kidney. Furthermore, NH3/NH4 (+) was not enriched in the urine, suggesting that kidneys are not involved in active NH3/NH4 (+) excretion. Exposure to elevated seawater pH of 8.5 transiently reduced NH3/NH4 (+) excretion rates, but they returned to control values following 24 h acclimation. These mussels had increased abundance of V-type H(+)-ATPase in the apical membranes of plicate organ cells; however, NH3/NH4 (+) excretion rates were not affected by the V-type H(+)-ATPase specific inhibitor concanamycin A (100 nmol l(-1)). In contrast, inhibition of ciliary beating with dopamine and increased seawater viscosity significantly reduced NH3 excretion rates under control pH (8.0). These results suggest that NH3/NH4 (+) excretion in mytilid mussels takes place by passive NH3 diffusion across respiratory epithelia via the Rh protein, facilitated by the water current produced for filter feeding, which prevents accumulation of NH3 in the boundary layer. This mechanism would be energy efficient for sessile organisms, as they already generate water currents for filter feeding. PMID:27489216

  3. Effect of seeding density on biomass production in mussel bottom culture

    NASA Astrophysics Data System (ADS)

    Capelle, Jacob J.; Wijsman, Jeroen W. M.; van Stralen, Marnix R.; Herman, Peter M. J.; Smaal, Aad C.

    2016-04-01

    Effects of seeding density on biomass production in mussel bottom culture are investigated by detailed monitoring of culture practice in the western Wadden Sea, The Netherlands. The seeds originate from different sources. The seeds differ in size and farmers apply seeding techniques dependent on the seed size resulting in different seed densities on the culture plots. We hypothesise growth to be density dependent and that biomass production is primarily determined by survival and is therefore a function of seed density which is related to the activities of the farmers. Data was collected from 42 different culture plots over a three year period (June 2009-June 2012). During this period, 66 sub-populations were followed from seeding until harvest. Seeding at the start of the culture resulted in an instantaneous drop in biomass production, caused by large losses in mussel number. These losses were on average 42% of the mussels seeded. This seeding loss decreased with mussel size and increased with seeding density. A subsequent density dependent loss of 1.8 mussels per day was found for smaller mussels (< 30 mm), and a non-density dependent loss of 0.8 mussels per day for larger mussels (> 30 mm) during grow out. Overall loss from seeding to harvest was high, from 92% for the smallest seeds collected from spat collectors, to 54% for half-grown mussels fished from natural beds in the spring. No indication was found that growth or mussel condition was affected by culture plot scale density. Growth was dependent on mussel size and age, and this largely determined the differences in biomass production between seed sources. The density dependent seeding loss associated with seeding activities largely determined survival, and hence overall biomass production.

  4. 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.

  5. Modelling growth variability in longline mussel farms as a function of stocking density and farm design

    NASA Astrophysics Data System (ADS)

    Rosland, Rune; Bacher, Cédric; Strand, Øivind; Aure, Jan; Strohmeier, Tore

    2011-11-01

    Mussels ( Mytilus edulis) are commonly cultivated on artificial structures like rafts, poles or longlines to facilitate farming operations. Farm structures and dense mussel populations may result in water flow reduction and seston depletion and thus reduced individual mussel growth and spatial growth variability inside a farm. One of the challenges in mussel farming is thus to scale and configure farms in order to optimise total mussel production and individual mussel quality under different environmental regimes. Here we present a spatially resolved model for simulation of flow reduction, seston depletion and individual mussel growth inside a longline farm based on information about farm configuration (spacing between longlines, farm length and stocking density) and background environmental conditions (current speed, seston concentration and temperature). The model simulations are forced by environmental data from two fjords in south-western Norway and the farm configurations are defined within operational ranges. The simulations demonstrate spatial growth patterns at longlines under environmental settings and farm configurations where flow reduction and seston depletion have significant impacts on individual mussel growth. Longline spacing has a strong impact on the spatial distribution of individual growth, and the spacing is characterised by a threshold value. Below the threshold growth reduction and spatial growth variability increase rapidly as a consequence of reduced water flow and seston supply rate, but increased filtration due to higher mussel densities also contributes to the growth reduction. The spacing threshold is moderated by other farm configuration factors and environmental conditions. Comparisons with seston depletion reported from other farm sites show that the model simulations are within observed ranges. A demonstration is provided on how the model can guide farm configuration with the aim of optimising total farm biomass and individual

  6. Modelling mussel growth in ecosystems with low suspended matter loads

    NASA Astrophysics Data System (ADS)

    Duarte, P.; Fernández-Reiriz, M. J.; Filgueira, R.; Labarta, U.

    2010-10-01

    Over the last decades a large number of bivalve growth models were described in the literature with most emphasis on cultivated species with important economic value. These models describe the rates of energy absorption and utilization as a function of environmental conditions. Some of the most important issues in bivalve modelling are water pumping, filtration, pre-ingestive rejection/pseudofaeces production and ingestion of living and non-living organic and inorganic matter. According to some authors, bivalve suspension-feeders may selectively ingest and/or digest different food items whilst making adjustments to maximize the utilization of chlorophyll rich particles. In clear water ecosystems such as the Galician Rias (total particulate matter ( TPM) < 3 mg l - 1 ), where most of the available seston is phytoplankton, selective processes may be less important than in turbid waters with high TPM loads. The main objectives of this work were to develop, implement and calibrate an Individual Based Model of mussel growth, configured and parameterized for the environmental conditions of ecosystems with low suspended matter loads such as the Galician Rias. Model runs were made for a large number of individual mussels, each with a random parameter set, selected among possible parameter ranges reported in the literature, allowing a quick model calibration and an evaluation of those parameters explaining most of the variance in predicted mussel growth. Obtained results provide a useful feedback for upcoming experimental work where efforts should be concentrated on accurate estimates of these more influential parameters to improve model results.

  7. Mercury-binding proteins from the marine mussel, Mytilus edulis

    SciTech Connect

    Roesijadi, G.

    1986-03-01

    The marine mussel, Mytilus edulis, possesses low molecular weight, metal-binding proteins which can be induced by and, in turn, bind mercury when individuals are exposed to low, but elevated concentrations of mercury as HgCl/sub 2/. Induction of the proteins by exposure of mussels to copper, cadmium, or mercury is associated with enhanced tolerance to mercury toxicity. Mercury-binding proteins isolated from gills of mussels occur as two molecular weight variants of about 20-25 and 10-12 kdaltons, respectively, on Sephadex G-75. These have been designated as HgBP/sub 20/ and HgBP/sub 10/ following the nomenclature used for cadmium-binding proteins. HgBP/sub 20/ represents the primary mercury-binding species. Separation of HgBP/sub 20/ by anion-exchange high-performance liquid chromatography resulted in the resolution of six peaks, indicating a more complex situation than was evident from DEAE-cellulose separations. Although not completely purified, these also contain cysteine- and glycine-rich proteins.

  8. Wresting the muscle from mussel beards: research and applications.

    PubMed

    Rzepecki, L M; Waite, J H

    1995-12-01

    Marine and zebra mussels secrete byssal beards to attach themselves opportunistically to hard surfaces in their environment. By doing this, they naturally earn a reputation as fouling pests. The protein precursors of byssus in mussels are being investigated in the hope not only of discovering specific measures against these marine foulers, but also to gain some insights into the technically challenging task of engineering adhesive bonds underwater. Although byssal proteins are all part of the bearded glue that bonds them to a surface, they can be subdivided into three types depending on the function that they serve in byssal threads: (1) fibrous proteins form the load-bearing cables in the core of the threads, (2) cuticular proteins form a protective coat around the cables, and (3) adhesive proteins connect the cables to a foreign surface. A flaw in any one of these will undermine a mussel's ability to attach. The fibrous proteins can be collagenous, silk-like, elastic, or any combination of these. Covering these are the cuticular proteins, which are distinguished by their surface coupling properties, tandemly repeated primary sequence, and their high content of lysine and the exotic amino acid 3,4-dihydroxyphenyl-L-alanine (DOPA). The adhesive proteins are of low molecular weight, contain DOPA, and assemble to form microcellular solids (foams). Several of these proteins are already attracting biotechnological attention as cell and tissue attachment factors, anticorrosives, and metal-sequestering reagents. PMID:8541982

  9. Glycosylated Hydroxytryptophan in a Mussel Adhesive Protein from Perna viridis*

    PubMed Central

    Zhao, Hua; Sagert, Jason; Hwang, Dong Soo; Waite, J. Herbert

    2009-01-01

    The 3,4-dihydroxyphenyl-l-alanine (Dopa)-containing proteins of mussel byssus play a critical role in wet adhesion and have inspired versatile new synthetic strategies for adhesives and coatings. Apparently, however, not all mussel adhesive proteins are beholden to Dopa chemistry. The cDNA-deduced sequence of Pvfp-1, a highly aromatic and redox active byssal coating protein in the green mussel Perna viridis, suggests that Dopa may be replaced by a post-translational modification of tryptophan. The N-terminal tryptophan-rich domain of Pvfp-1 contains 42 decapeptide repeats with the consensus sequences ATPKPW1TAW2K and APPPAW1TAW2K. A small collagen domain (18 Gly-X-Y repeats) is also present. Tandem mass spectrometry of isolated tryptic decapeptides has detected both C2-hexosylated tryptophan (W1) and C2-hexosylated hydroxytryptophan (W2), the latter of which is redox active. The UV absorbance spectrum of W2 is consistent with 7-hydroxytryptophan, which represents an intriguing new theme for bioinspired opportunistic wet adhesion. PMID:19584055

  10. Radionuclides in Peconic River fish, mussels, and sediments.

    PubMed

    Rapiejko, A; Rosson, R; Lahr, J; Garcia, R; Kahn, B

    2001-12-01

    For regulatory oversight and quality control of Comprehensive Environmental Response, Compensation, and Liability Act (CERCLA) actions, fish, mussels, and sediments were analyzed from the Peconic River system on Long Island, NY, downstream of the Brookhaven National Laboratory, as well as from control locations. The analyses were for photon-emitting radionuclides (notably 60Co and 137Cs), uranium, plutonium, and americium. Sediments were cored in 4 sections to 0.37 m depth, whole fish were analyzed, and mussels were separated into flesh and shells. Radioisotopes of the cited elements were detected in sediment, some of the fish contained 137Cs, 241Am, and uranium, and mussel flesh contained 137Cs and uranium. All of the 60Co, 233U, and enriched uranium, and some of the 137Cs and 241Am, can most likely be attributed to Brookhaven National Laboratory. The other radionuclides (and some of the 137Cs and 241Am) are believed to have either fallout or nature as their origin. The New York State Department of Health (NYSDOH) evaluated the radiological data in terms of adverse health implications due to consumption of fish with the levels of reported radioactivity. The NYSDOH determined that the added radiation doses likely to result from eating this fish are a small fraction of the radiation dose that normally results from radionuclides present in the body from natural sources. PMID:11725889

  11. Mussel-mimetic protein-based adhesive hydrogel.

    PubMed

    Kim, Bum Jin; Oh, Dongyeop X; Kim, Sangsik; Seo, Jeong Hyun; Hwang, Dong Soo; Masic, Admir; Han, Dong Keun; Cha, Hyung Joon

    2014-05-12

    Hydrogel systems based on cross-linked polymeric materials which could provide both adhesion and cohesion in wet environment have been considered as a promising formulation of tissue adhesives. Inspired by marine mussel adhesion, many researchers have tried to exploit the 3,4-dihydroxyphenylalanine (DOPA) molecule as a cross-linking mediator of synthetic polymer-based hydrogels which is known to be able to achieve cohesive hardening as well as adhesive bonding with diverse surfaces. Beside DOPA residue, composition of other amino acid residues and structure of mussel adhesive proteins (MAPs) have also been considered important elements for mussel adhesion. Herein, we represent a novel protein-based hydrogel system using DOPA-containing recombinant MAP. Gelation can be achieved using both oxdiation-induced DOPA quinone-mediated covalent and Fe(3+)-mediated coordinative noncovalent cross-linking. Fe(3+)-mediated hydrogels show deformable and self-healing viscoelastic behavior in rheological analysis, which is also well-reflected in bulk adhesion strength measurement. Quinone-mediated hydrogel has higher cohesive strength and can provide sufficient gelation time for easier handling. Collectively, our newly developed MAP hydrogel can potentially be used as tissue adhesive and sealant for future applications. PMID:24650082

  12. A mussel-derived one component adhesive coacervate.

    PubMed

    Wei, Wei; Tan, Yerpeng; Martinez Rodriguez, Nadine R; Yu, Jing; Israelachvili, Jacob N; Waite, J Herbert

    2014-04-01

    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. The 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 the 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 non- polar 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 ⩽1mJm(-2), 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

  13. Methanotrophic marine molluscan (Bivalvia, Mytilidae) symbiosis: mussels fueled by gas

    SciTech Connect

    Childress, J.J.; Fisher, C.R.; Brooks, J.M.; Kennicutt, M.C. II; Bidigare, R.; Anderson, A.E.

    1986-09-19

    An undescribed mussel (family Mytilidae), which lives in the vicinity of hydrocarbon seeps in the Gulf of Mexico, consumes methane (the principal component of natural gas) at a high rate. The methane consumption is limited to the gills of these animals and is apparently due to the abundant intracellular bacteria found there. This demonstrates a methane-based symbiosis between an animal and intracellular bacteria. Methane consumption is dependent on the availability of oxygen and is inhibited by acetylene. The consumption of methane by these mussels is associated with a dramatic increase in oxygen consumption and carbon dioxide production. As the methane consumption of the bivalve can exceed its carbide dioxide production, the symbiosis may be able to entirely satisfy its carbon needs from methane uptake. The very light (delta/sup 13/C = -51 to -57 per mil) stable carbon isotope ratios found in this animal support methane (delta/sup 13/C = -45 per mil at this site) as the primary carbon source for both the mussels and their symbionts. 19 references, 2 figures, 1 table.

  14. Zebra mussel control using periodic chlorine dioxide treatments

    SciTech Connect

    Tsou, J.; Coyle, J.; Crone, D.

    1996-08-01

    This paper summarizes the EPRI report (TR-105202) on the same topic as well as presents changes in current thinking on the suitability (applicability) of chlorine dioxide for fouling control. Chlorine dioxide was tested as a zebra mussel biocide at two steam electric generating stations in Illinois and one in Indiana. The purpose of these studies was to determine the efficacy of chlorine dioxide in killing zebra mussels and to develop site specific treatment programs for the three utilities. The Electric Power Research Institute (EPRI) Zebra Mussel Consortium sponsored the testing of this recent use of chlorine dioxide. The raw water system at Central Illinois Public Service`s Meredosia Station, on the Illinois River, received applications of chlorine dioxide in April, July, and September 1994. The raw water system at Illinois Power Company`s Wood River Station, on the Mississippi River, received applications in July 1993, January, April, May, July, and September 1994. The Gallagher Station, on the Ohio River, was treated in July and October 1994. Chlorine dioxide was generated on-site and injected into the water intake structure. Both cooling and service water systems were treated at the facilities. 6 refs., 13 figs.

  15. Mortality, movement and behaviour of native mussels during a planned water-level drawdown in the Upper Mississippi River

    USGS Publications Warehouse

    Newton, Teresa J.; Zigler, Steven J.; Gray, Brian R.

    2015-01-01

    Collectively, these data suggest that drawdowns can influence the mortality, movement and behaviour of mussels in the UMR. However, more information on spatial and temporal distributions of mussels is needed to better understand the magnitude of these effects. Results from this study are being used by resource managers to better evaluate the effects of this management tool on native mussel assemblages.

  16. An analysis of mussel bed habitats in the Dutch Wadden Sea

    NASA Astrophysics Data System (ADS)

    Brinkman, A. G.; Dankers, N.; van Stralen, M.

    2002-04-01

    A habitat suitability analysis for littoral mussel beds in the Dutch Wadden Sea was carried out. The analysis was based on the presence of mussel beds in the years 1960-1970, and a number of environmental characteristics: wave action, flow velocity, median grain size, emersion times and distance to a gully border. The habitat model describes mussel bed appearance quantitatively. It predicts the distribution of mussel beds quite well, as well as the distribution of spatfall in the years 1994 and 1996. From the analysis we found that wave action (maximum orbital velocity) was the main structuring factor. A low orbital velocity was preferred. Neither very low, nor maximum flow velocities were favourable for mussel beds. Very coarse sands or silty environments were not preferred. Sites close to the low water line showed lower mussel bed appearance; when emersion time was above 50% , hardly any mussel beds could be found. The habitat suitability analysis and the construction of a habitat suitability map was performed in the framework of the discussions on a further or reduced exploitation of the tidal flats in the Dutch Wadden Sea by cockle and mussel fishery activities.

  17. Bioactive compounds from marine mussels and their effects on human health.

    PubMed

    Grienke, Ulrike; Silke, Joe; Tasdemir, Deniz

    2014-01-01

    The consumption of marine mussels as popular seafood has increased steadily over the past decades. Awareness of mussel derived molecules, that promote health, has contributed to extensive research efforts in that field. This review highlights the bioactive potential of mussel components from species of the genus Mytilus (e.g. M. edulis) and Perna (e.g. P. canaliculus). In particular, the bioactivity related to three major chemical classes of mussel primary metabolites, i.e. proteins, lipids, and carbohydrates, is evaluated. Within the group of proteins the focus is mainly on mussel peptides e.g. those obtained by bio-transformation processes, such as fermentation. In addition, mussel lipids, comprising polyunsaturated fatty acids (PUFAs), are discussed as compounds that are well known for prevention and treatment of rheumatoid arthritis (RA). Within the third group of carbohydrates, mussel polysaccharides are investigated. Furthermore, the importance of monitoring the mussel as food material in respect to contaminations with natural toxins produced by microalgae is discussed. PMID:24001811

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

    SciTech Connect

    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.

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

    USGS Publications Warehouse

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

    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.

  20. SPATIAL VARIABILITY IN MUSSELS USED TO ASSESS BASE LEVEL NITROGEN ISOTOPE RATIO IN FRESHWATER ECOSYSTEMS

    EPA Science Inventory

    Freshwater mussels have been used to establish base level nitrogen isotope ratio values ( 15N) used in trophic position and food web studies in freshwater ecosystems. In this study, we assess the variability introduced when using unionid mussels in this manner by investigating th...

  1. ZEBRA MUSSEL COLONIZATION OF RUSTY CRAYFISH IN GREEN BAY, LAKE MICHIGAN

    EPA Science Inventory

    In August, 1995 six rusty crayfish colonized with zebra mussels were captured in small-meshed fyke-nets sets set apart as of a fish sampling effort at Peter's Marsh and Long-Tail Point Wetland in lower Green Bay. Mussels colonized virtually all areas of the crayfish bodies, but ...

  2. 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.

  3. Effects of a municipal effluent on the freshwater mussel Elliptio complanata following challenge with Vibrio anguillarum.

    PubMed

    François, Gagné; Mélanie, Douville; Marlène, Fortier; Michel, Fournier

    2015-11-01

    The purpose of this study was to examine the cumulative effects of exposure to a pathogenic bacteria and municipal effluent in the freshwater mussel Elliptio complanata. Mussels were exposed to increasing concentrations of an ozone-treated effluent at 15°C for 7days. A sub-group of mussels was inoculated with Vibrio anguillarum and exposed to the same conditions as above. After the exposure period, mussels were collected to assess hemocyte count and viability, immunocompetence (phagocytosis and nitrite production), oxidative stress/inflammation (cyclooxygenase and lipid peroxidation) and oxygen radical/xenobiotic scavenging activity (metallothioniens, glutathione S-transferase). The results showed that mussels exposed to municipal effluent had increased hemocyte counts, phagocytosis, nitrites, lipid peroxidation and metallothioneins. In the inoculated mussels, the same responses were observed, in addition to cyclooxygenase and glutathione S-transferase activities. Multivariate analyses revealed that (1) the response pattern changed with effluent concentration, where increased responses observed at low effluent concentrations (>10%, V/V) were attenuated at higher effluent concentrations, (2) the effluent produced more pronounced changes in lipid peroxidation, metallothionein and hemocyte viability, and (3) the simultaneous presence of V. anguillarum led to more important changes in hemocyte count and viability and nitrite levels. In conclusion, the presence of V. anguillarum could alter the response of mussels to municipal effluent, which could lead to increased inflammation in mussels. PMID:26574092

  4. Comparison of freshwater mussel communities from 1988 to 2015 in the Cedar Creek Watershed, Indiana

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Out of the 300 genera of freshwater mussels (Unionidae) represented in North America, most species have shown declines in abundance and distribution largely due to human-mediated factors. This study compares current community composition, abundance and richness of mussels in Cedar Creek, Indiana wit...

  5. 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...

  6. 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. PMID:25042075

  7. Detoxification and protein quality control markers in the mussel Mytilus edulis (Linnaeus) exposed to crude oil: Salinity-induced modulation

    NASA Astrophysics Data System (ADS)

    Lysenko, Liudmila; Sukhovskaya, Irina; Borvinskaya, Ekaterina; Krupnova, Marina; Kantserova, Nadezda; Bakhmet, Igor'; Nemova, Nina

    2015-12-01

    Marine and coastal ecosystems are influenced by oil from chronic contamination or sporadic oil spills. An oil spill was simulated in an aquarium-based experiment designed to reproduce interactions of crude oil with inert environmental components, particularly adhesion on shore gravel and dissolution in sea water. Total experimental oil concentrations were in the range of comparable hydrocarbon concentrations following an oil spill. Furthermore, the possible interaction of a chemical (anthropogenic) stressor, such as oil PAHs, and a "natural" stressor like desalination, was simulated. In order to assess the biological effects of crude oil contamination and desalination (each individually and in combination) on the blue mussel Mytilus edulis L., biochemical responses were estimated including: detoxification capacity by glutathione-S-transferase (GST) activity, reduced glutathione (GSH) level, and protein quality control by autophagy-related proteases cathepsin B (CatB), cathepsin D (CatD), and calcium-dependent calpain-like proteases. Oil treatment stimulated defense system response in the mussels with primary effects on GST and protease-mediated reactions such as the activation of CatB, CatD, and calpains. Most of biomarkers responded to oil in a dose- and time-dependent manner. Additional environmental stress, such as desalination, promoted the oil-induced activation of GST and CatD while resulting in a delay or impairement of the defense response to oil by GSH and proteases CatB and calpains. Thus, biomarker data shows that combined effects of oil compounds and desalination can be realized in both a synergistic and an antagonistic manner. The evaluated interaction between oil pollution effects and sub-optimal salinity on M. edulis indicates the potential risk of maladaptation to the biota of estuaries.

  8. Modeling and predicting the growth of the mussel, Mytilus edulis: implications for planning of aquaculture and eutrophication mitigation.

    PubMed

    Bergström, Per; Lindegarth, Susanne; Lindegarth, Mats

    2015-12-01

    The increased pressure on the marine ecosystems highlights the need for policies and integrated approaches for sustainable management of coastal areas. Spatial planning based on geographic information of human activities, ecological structures and functions, and their associated goods and services is a fundamental component in this context. Here, we evaluate the potential of predictive modeling to provide spatial data on one ecosystem function, mussel growth for use in such processes. We developed a methodology based on statistical modeling, spatial prediction, and mapping for the relative growth of the blue mussel, Mytilus edulis. We evaluated the performance of different modeling techniques and classification schemes using empirical measurements of growth from 144 sampling sites and data on biological, chemical, and physical predictors. Following comparisons of the different techniques and schemes, we developed random forest models to predict growth along the Swedish west coast. Implemented into GIS the best model produced in this study predicts that low, intermediate, and high growth rates can be expected in 53%, 32%, and 15% of modeled area, respectively. The results of this study also suggest that the nature and quality of predictor data hold the key to improving the predictive power of models. On a more general note, this study exemplifies a feasible approach based on measuring, modeling, and mapping for obtaining scientifically based spatial information on ecosystem functions and services affected by a complex set of factors. Such information is fundamental for maritime spatial planning and ecosystem-based management and its importance is likely to increase in the future. Because of its close link to nutrient assimilation and production yield, site-specific information of soft tissue growth such as the map of predicted growth rate developed in this study can be used as a tool for optimizing actions aimed at mitigating eutrophication and aquaculture

  9. Disturbance of eelgrass Zostera marina by commercial mussel Mytilus edulis harvesting in Maine: dragging impacts and habitat recovery

    USGS Publications Warehouse

    Neckles, H.A.; Short, F.T.; Barker, S.; Kopp, B.S.

    2005-01-01

    We studied the effects of commercial harvest of blue mussels Mytilus edulis on eelgrass Zostera marina L. in Maquoit Bay, Maine, USA, at a hierarchy of scales. We used aerial photography, underwater video, and eelgrass population- and shoot-based measurements to quantify dragging impacts within 4 sites that had been disturbed at different times over an approximate 7 yr interval, and to project eelgrass meadow recovery rates. Dragging had disturbed 10% of the eelgrass cover in Maquoit Bay, with dragged sites ranging from 3.4 to 31.8 ha in size. Dragging removed above- and below-ground plant material from the majority of the bottom in the disturbed sites. One year following dragging, eelgrass shoot density, shoot height and total biomass of disturbed sites averaged respectively 2 to 3%, 46 to 61% and < 1% that of the reference sites. Substantial differences in eelgrass biomass persisted between disturbed and reference sites up to 7 yr after dragging. Dragging did not affect physical characteristics of the sediment. The pattern and rate of eelgrass bed recovery depended strongly on initial dragging intensity; areas of relatively light dragging with many remnant eelgrass patches (i.e. patches that were missed by the mussel dredge) showed considerable revegetation in 1 yr. However, by developing recovery trajectories from measurements at sites disturbed in different years, we projected that it would require a mean of 10.6 yr for recovery of eelgrass shoot density within the areas of intense dragging characterizing most of the disturbed sites. A spatial simulation model based on measured rates of lateral patch-expansion (mean 12.5 cm yr(-1)) and new-patch recruitment (mean 0.19 patches m(-2) yr(-1)) yielded a mean bed recovery time of 9 to 11 yr following dragging, depending on initial degree of plant removal. Model simulations suggested that with favorable environmental conditions, eelgrass beds might recover from dragging disturbance in 6 yr; conversely, recovery under

  10. Disturbance of eelgrass Zostera marina by commercial mussel Mytilus edulis harvesting in Maine: Dragging impacts and habitat recovery

    USGS Publications Warehouse

    Neckles, H.A.; Short, F.T.; Barker, S.; Kopp, B.S.

    2005-01-01

    We studied the effects of commercial harvest of blue mussels Mytilus edulis on eelgrass Zostera marina L. in Maquoit Bay, Maine, USA, at a hierarchy of scales. We used aerial photography, underwater video, and eelgrass population- and shoot-based measurements to quantify dragging impacts within 4 sites that had been disturbed at different times over an approximate 7 yr interval, and to project eelgrass meadow recovery rates. Dragging had disturbed 10% of the eelgrass cover in Maquoit Bay, with dragged sites ranging from 3.4 to 31.8 ha in size. Dragging removed above- and belowground plant material from the majority of the bottom in the disturbed sites. One year following dragging, eelgrass shoot density, shoot height and total biomass of disturbed sites averaged respectively 2 to 3 %, 46 to 61 % and <1 % that of the reference sites. Substantial differences in eelgrass biomass persisted between disturbed and reference sites up to 7 yr after dragging. Dragging did not affect physical characteristics of the sediment. The pattern and rate of eelgrass bed recovery depended strongly on initial dragging intensity; areas of relatively light dragging with many remnant eelgrass patches (i.e. patches that were missed by the mussel dredge) showed considerable revegetation in 1 yr. However, by developing recovery trajectories from measurements at sites disturbed in different years, we projected that it would require a mean of 10.6 yr for recovery of eelgrass shoot density within the areas of intense dragging characterizing most of the disturbed sites. A spatial simulation model based on measured rates of lateral patch-expansion (mean 12.5 cm yr-1) and new-patch recruitment (mean 0.19 patches m-2 yr-1) yielded a mean bed recovery time of 9 to 11 yr following dragging, depending on initial degree of plant removal. Model simulations suggested that with favorable environmental conditions, eelgrass beds might recover from dragging disturbance in 6 yr; conversely, recovery under

  11. Blue ellipticals in compact groups

    NASA Technical Reports Server (NTRS)

    Zepf, Stephen E.; Whitmore, Bradley C.

    1990-01-01

    By studying galaxies in compact groups, the authors examine the hypothesis that mergers of spiral galaxies make elliptical galaxies. The authors combine dynamical models of the merger-rich compact group environment with stellar evolution models and predict that roughly 15 percent of compact group ellipticals should be 0.15 mag bluer in B - R color than normal ellipticals. The published colors of these galaxies suggest the existence of this predicted blue population, but a normal distribution with large random errors can not be ruled out based on these data alone. However, the authors have new ultraviolet blue visual data which confirm the blue color of the two ellipticals with blue B - R colors for which they have their own colors. This confirmation of a population of blue ellipticals indicates that interactions are occurring in compact groups, but a blue color in one index alone does not require that these ellipticals are recent products of the merger of two spirals. The authors demonstrate how optical spectroscopy in the blue may distinguish between a true spiral + spiral merger and the swallowing of a gas-rich system by an already formed elliptical. The authors also show that the sum of the luminosity of the galaxies in each group is consistent with the hypothesis that the final stage in the evolution of compact group is an elliptical galaxy.

  12. Blue moons and Martian sunsets.

    PubMed

    Ehlers, Kurt; Chakrabarty, Rajan; Moosmüller, Hans

    2014-03-20

    The familiar yellow or orange disks of the moon and sun, especially when they are low in the sky, and brilliant red sunsets are a result of the selective extinction (scattering plus absorption) of blue light by atmospheric gas molecules and small aerosols, a phenomenon explainable using the Rayleigh scattering approximation. On rare occasions, dust or smoke aerosols can cause the extinction of red light to exceed that for blue, resulting in the disks of the sun and moon to appear as blue. Unlike Earth, the atmosphere of Mars is dominated by micron-size dust aerosols, and the sky during sunset takes on a bluish glow. Here we investigate the role of dust aerosols in the blue Martian sunsets and the occasional blue moons and suns on Earth. We use the Mie theory and the Debye series to calculate the wavelength-dependent optical properties of dust aerosols most commonly found on Mars. Our findings show that while wavelength selective extinction can cause the sun's disk to appear blue, the color of the glow surrounding the sun as observed from Mars is due to the dominance of near-forward scattering of blue light by dust particles and cannot be explained by a simple, Rayleigh-like selective extinction explanation. PMID:24663457

  13. Accumulation and depuration of cyanobacterial paralytic shellfish toxins by the freshwater mussel Anodonta cygnea.

    PubMed

    Pereira, Paulo; Dias, Elsa; Franca, Susana; Pereira, Elisa; Carolino, Manuela; Vasconcelos, Vitor

    2004-07-14

    The increasing frequency by which the production of paralytic shellfish toxins (PST) by freshwater bloom-forming cyanobacteria is being noticed world-wide raises the possibility of PST bioaccumulation by freshwater mussels. This study evaluates PST accumulation and depuration by the freshwater mussel Anodonta cygnea exposed over a 14-day period to high densities (mean = 1.4 x 10(9) cells1(-1), S.D. = 0.29 x 10(9) cellsl(-1)) of the toxic cyanobacterium Aphanizomenon issatschenkoi (corresponding to a mean toxin concentration of 25.5 nmol PSTl(-1), S.D. = 9.9 nmol PSTl(-1)). Mussels were subsequently detoxified either by starvation or by feeding on the non-toxic green-algae Ankistodesmus falcatus. Filter feeding activity and toxin uptake by the mussels were followed by cell counting and toxin analysis in water samples taken before and after each daily water renewal. The accumulation and depuration of PST as well as the anatomical distribution of toxins were monitored throughout the experiment by HPLC analysis of mussel extracts. Mussels fed the toxic cyanobacterium removed on average 65.3% of cells and 40.36% of total PST daily provided. Daily rates of cell clearance (% of initial) were negatively correlated with the amounts of PST daily provided (but not with the amount of cells). This suggests a negative effect of toxins on the feeding behaviour of mussels. Small amounts of toxins could be detected in the mussels after the second day of exposure, reaching a maximum of 26 microg PST100 g(-1) by day 7. The viscera contained the greatest proportion of toxins (78%) at the start of the toxification. However, increasing amounts of PST were found in the remaining tissues (gills, mantle and foot) over time. Toxins detected in the mussel extracts were the same provided in the dietary A. issatschenkoi. Nevertheless, mussels showed a higher proportion of saxitoxin and decarbomoylsaxitoxin and a lower proportion of gonyautoxin-5 than the fed cyanobacterium. Similar depuration

  14. Blue upconversion thulium laser

    SciTech Connect

    Nguyen, D.C.; Faulkner, G.E.; Weber, M.E.; Dulick, M.

    1990-01-01

    Upconversion has been an active area of research for at least two decades, mainly because of its wide ranging applications from infrared quantum counters, visible-emitting phosphors, to upconversion lasers. The upconversion lasers have recently become attractive with the advent of semiconductor laser diodes as the pump source. In an upconversion laser, the laser active ion is excited by internal upconversion of near-ir or red light via multiphoton excitation or cooperative processes and emits anti-Stokes visible light. Since the laser diode output wavelength can be composition turned to match the upconversion laser ion absorption lines, a substantial fraction of the ions can be driven into higher energy levels, thus enhancing the upconversion process. These upconversion solid-state lasers offer a potentially simple and compact source of visible coherent light with semiconductor laser diode excitation. We recently reported a novel upconversion thulium laser that emits blue light at 77 K. In this paper additional data on this 77 K upconversion laser as well as preliminary results on the room temperature upconversion laser are presented. In these demonstrations, dye lasers were used instead of diode lasers because they were more readily available than high power semiconductor laser diodes and their wavelengths could be adjusted easily. 14 refs., 5 figs., 1 tab.

  15. Characterizing the effect of heavy metal contamination on marine mussels using metabolomics.

    PubMed

    Kwon, Yong-Kook; Jung, Young-Sang; Park, Jong-Chul; Seo, Jungju; Choi, Man-Sik; Hwang, Geum-Sook

    2012-09-01

    Marine mussels (Mytilus) are widely used as bioindicators to measure pollution in marine environments. In this study, (1)H NMR spectroscopy and multivariate statistical analyses were used to differentiate mussel groups from a heavy metal-polluted area (Onsan Bay) and a clean area (Dokdo area). Principal component analysis and orthogonal projection to latent structure-discriminant analysis revealed significant separation between extracts of mussels from Onsan Bay and from the Dokdo area. Organic osmolytes (betaine and taurine) and free amino acids (alanine, arginine, glutamine, phenylalanine, and threonine) were more highly accumulated in Onsan Bay mussels compared with Dokdo mussels. These results demonstrate that NMR-based metabolomics can be used as an efficient method for characterizing heavy metal contamination derived from polluted area compared to clean area and to identify metabolites related to environments that are contaminated with heavy metals. PMID:22770532

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

    USGS Publications Warehouse

    French, John R. P., III; 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.

  17. Complete mitochondrial genome of the Asian green mussel Perna viridis (Bivalvia, Mytilidae).

    PubMed

    Li, Xiaoling; Wu, Xiangyun; Yu, Ziniu

    2012-10-01

    The complete mitochondrial (mt) genome of the Asian green mussel Perna viridis (16,627 bp), an economically important bivalve, was newly sequenced and annotated. P. viridis is the shortest and has a comparatively highest overall A+T content (68%) among six available genomes of marine mussels to date. The atp8 gene's length (49 a.a.) of the green mussel is unexpectedly greatly shorter than that of other marine mussels (87 a.a.). Comparison of the gene order demonstrated that the six marine mussels share no identical gene blocks although they belong to the same family, which indicates that this group should be a good model to study mtDNA evolution and mitochondria inheritance. PMID:22708864

  18. 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. PMID:16593208

  19. Assessment of metal element concentrations in mussel (M. Galloprovincialis) in Eastern Black Sea, Turkey.

    PubMed

    Cevik, U; Damla, N; Kobya, A I; Bulut, V N; Duran, C; Dalgic, G; Bozaci, R

    2008-12-30

    The main goal of this work is to determine the effects of pollution of copper, lead and zinc mines on the Eastern Black Sea. Metal and heavy metal concentrations in the Eastern Black Sea mussels were measured using Energy Dispersive X-ray Fluorescence (EDXRF) and Flame Atomic Absorption Spectroscopy (FAAS). The analytical results showed that the tissue of mussel in Eastern Black Sea contains K, Ca, Fe, Cu, Zn, and Sr elements, and the shell of mussel contains Ca, Cu, Sr, and Ba elements. Due to the detection limit of EDXRF, the mussels were analyzed with FAAS for Cr, Mn, Ni, Cd and Pb elements. An ANOVA and Pearson correlation analyses were performed. The results showed although that the mean concentrations of Cu and Zn for the tissue of the mussels were markedly above the permissible levels of the Turkish regulations, Zn concentration is in the limits of the Food and Agriculture Organization (FAO). PMID:18417277

  20. The complete F-type mitochondrial genome of Chinese freshwater mussel Anodonta euscaphys.

    PubMed

    Xue, Ting; Chen, Meiling; Wang, Guiling; Han, Zhenyong; Li, Jiale

    2016-07-01

    Anodonta euscaphys is the endemic species of freshwater mussel in China. The complete F-type mitochondrial genome of the A. euscaphys is amplified and analyzed in this study. It is 15,741 bp in length. The base composition of the genome with A + T bias is 64.78%. There are 24 noncoding regions found throughout the mitogenome of A. euscaphys, ranging in size from 3 to 302 bp, the largest of which was between ND2 and tRNA(Glu). The phylogenetic tree based on 22 mitogenome, including 16 F-type freshwater mussels, 2 M-type freshwater mussels and 4 marine mussels were analyzed in our study, the results showed that the F-type and the M-type of the freshwater mussels were clustered respectively, the A. euscaphys was clustered with Anodonta family species firstly, and it was the closest to the Anodonta arcaeformis in our analysis. PMID:26000937

  1. Impact of European zebra mussel infestation to the electric power industry

    SciTech Connect

    McMahon, R.F. )

    1990-01-01

    This paper reports on Dreissena polymorpha, the European freshwater zebra mussel, introduced to the Great Lakes in 1985. It is now found throughout Lakes St. Clair and Erie, in Green Bay, Lake Michigan and invaded western Lake Ontario by Fall 1989. As its planktonic veliger larva is dispersed on water currents and adults are transported by human and natural vectors, it is likely to spread throughout U.S. and southern Canadian freshwaters. Mussel accumulations impede flow, and aggravate sedimentation and corrosion. Settlement occurs at flow velocities less than 1.5-2.0 m/sec. Mussels foul intake structures, low-flow piping, steam condensors, heat exchangers, fire protection systems, and cooling tower basins. Monitoring of source waters for mussels and veligers allows initiation of control measures before macrofouling occurs. Mussel fouling should be prevented as removal is difficult and expensive.

  2. Histopathological and apoptotic changes on marine mussels Mytilus galloprovincialis (Lamark, 1819) following exposure to environmental pollutants.

    PubMed

    Yavaşoğlu, Altuğ; Özkan, Dilara; Güner, Adem; Katalay, Selma; Oltulu, Fatih; Yavaşoğlu, N Ülkü Karabay

    2016-08-15

    Marine bivalve mussels, especially Mytilus species are an earlywarning system used for determining of damage caused by the various aquatic pollutions. In the present study, Mytilus galloprovincialis L. (black mussel) have been utilised as a biomonitoring organism to reveal environmental pollution in the Aliaga, Foca and Urla where located along the Izmir Coast of Turkey. Mussels were collected at these areas and gill and hepatopancreas (digestive gland) tissues were excised. mRNA expressions of initiator (caspase-2 and -8) and executioner (caspase -3/7-1, -3/7-2, -3/7-3 and -3/7-4) caspases of mussels tissues in areas exposed to pollution agent have been observed. TUNEL immunoreactivity in paralel to histopathological changes in both Aliaga and Foca areas were compared with Urla. This study is the first report to reveal the pollution with apoptotic expression on mussels in the coast of Turkey. PMID:27301687

  3. Blue metal complex pigments involved in blue flower color

    PubMed Central

    Takeda, Kosaku

    2006-01-01

    The blue pigment of cornflower, protocyanin, has been investigated for a long time, but its precise structure was not entirely explained until recently. The molecular structure of the pigment was recently shown to be a metal complex of six molecules each of anthocyanin and flavone glycoside, with one ferric iron, one magnesium and two calcium ions by X-ray crystallographic analysis. The studies provided the answer to the question posed in the early part of the last century, “why is the cornflower blue and rose red when both flowers contain the same anthocyanin?” This work was achieved on the basis of the results of long years of the studies made by many researchers. In this review, the author focuses on the investigations of the blue metal complex pigments involved in the bluing of flowers, commelinin from Commelina commusis, protocyanin from Centaurea cyanus, protodelphin from Salvia patens and hydrangea blue pigment. PMID:25792777

  4. 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.

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

    PubMed

    Peyer, Suzanne M; Hermanson, John C; Lee, Carol Eunmi

    2011-07-01

    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 such differences are unknown. We examined effects of shell morphology on locomotion for the three morphotypes on hard (typical of shallow habitats) and soft (characteristic of deep habitats) sedimentary substrates. We quantified morphology using the polar moment of inertia, a parameter used in calculating kinetic energy that describes shell area distribution and resistance to rotation. We quantified mussel locomotion by determining the ratio of rotational (K(rot)) to translational kinetic energy (K(trans)). On hard substrate, K(rot):K(trans) of deep quagga mussels was fourfold greater than for the other morphotypes, indicating greater energy expenditure in rotation relative to translation. On soft substrate, K(rot):K(trans) of deep quagga mussels was approximately one-third of that on hard substrate, indicating lower energy expenditure in rotation on soft substrate. Overall, our study demonstrates that shell morphology correlates with differences in locomotion (i.e. K(rot):K(trans)) among morphotypes. Although deep quagga mussels were similar to zebra and shallow quagga mussels in terms of energy expenditure on sedimentary substrate, their morphology was energetically maladaptive for linear movement on hard substrate. As quagga mussels can possess two distinct morphotypes (i.e. shallow and deep morphs), they might more effectively utilize a broader range of substrates than zebra mussels, potentially enhancing their ability to colonize a wider range of habitats. PMID:21653816

  6. 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

  7. Tolerance of five species of tropical marine mussels to continuous chlorination.

    PubMed

    Rajagopal, S; Venugopalan, V P; Van der Velde, G; Jenner, H A

    2003-05-01

    The paper examines the relative lethal and sublethal response of five important tropical marine mussels (Perna viridis, Perna perna, Brachidontes striatulus, Brachidontes variabilis and Modiolus philippinarum) to different chlorine concentrations varying from 0.25 to 15 mg l(-1). The mussels were observed to co-exist in the cooling water circuits of a coastal power station that adopted intermittent chlorination as a fouling control technique. The five mussel species showed, in response to chlorination, 100% mortality at significantly different exposure times, indicating significant species-specific variability in chlorine tolerance. For example, at 1 mg l(-1) residual chlorine, B. variabilis and P. viridis took 288 and 816 h, respectively, to achieve 100% mortality. The time taken for 100% mortality decreased with increasing chlorine residual concentration. The effect of mussel size (= mussel age) of P. viridis, P. perna, B. striatulus and M. philippinarum on mortality was significant between 1 and 5 mg l(-1) residual chlorine, with larger mussels showing greater resistance than smaller ones. All mussel species showed progressive reduction in physiological activities when chlorine residuals were increased from 0 to 1 mg l(-1). However, species-specific differences in the relative rate of physiological activities were observed. Accordingly, relative reduction in physiological activities in response to chlorination was the lowest in P. viridis and the highest in B. variabilis. The data clearly indicate significant differences in the lethal and sublethal responses of the five mussel species to chlorination. The results, therefore, suggest that for effective fouling control, chlorine treatment against mussels has to be employed judiciously, depending on the mussel species involved. PMID:12517421

  8. 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, J.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

  9. Economic impacts of zebra mussels on drinking water treatment and electric power generation facilities.

    PubMed

    Connelly, Nancy A; O'Neill, Charles R; Knuth, Barbara A; Brown, Tommy L

    2007-07-01

    Invasions of nonnative species such as zebra mussels can have both ecological and economic consequences. The economic impacts of zebra mussels have not been examined in detail since the mid-1990s. The purpose of this study was to quantify the annual and cumulative economic impact of zebra mussels on surface water-dependent drinking water treatment and electric power generation facilities (where previous research indicated the greatest impacts). The study time frame was from the first full year after discovery in North America (Lake St. Clair, 1989) to the present (2004); the study area was throughout the mussels' North American range. A mail survey resulted in a response rate of 31% for electric power companies and 41% for drinking water treatment plants. Telephone interviews with a sample of nonrespondents assessed nonresponse bias; only one difference was found and adjusted for. Over one-third (37%) of surveyed facilities reported finding zebra mussels in the facility and almost half (45%) have initiated preventive measures to prevent zebra mussels from entering the facility operations. Almost all surveyed facilities (91%) with zebra mussels have used control or mitigation alternatives to remove or control zebra mussels. We estimated that 36% of surveyed facilities experienced an economic impact. Expanding the sample to the population of the study area, we estimated 267 million dollars (BCa 95% CI = 161 million dollars - 467 million dollars) in total economic costs for electric generation and water treatment facilities through late 2004, since 1989. Annual costs were greater (44,000 dollars/facility) during the early years of zebra mussel infestation than in recent years (30,000 dollars). As a result of this and other factors, early predictions of the ultimate costs of the zebra mussel invasion may have been excessive. PMID:17530329

  10. Validation of the danish national diabetes register.

    PubMed

    Green, Anders; Sortsø, Camilla; Jensen, Peter Bjødstrup; Emneus, Martha

    2015-01-01

    The Danish National Diabetes Register (NDR) was established in 2006 and builds on data from Danish health registers. We validated the content of NDR, using full information from the Danish National Patient Register and data from the literature. Our study indicates that the completeness in NDR is ≥95% concerning ascertainment from data sources specific for diabetes, ie, prescriptions with antidiabetic drugs and diagnoses of diabetes in the National Patient Register. Since the NDR algorithm ignores diabetes-related hospital contacts terminated before 1990, the establishment of the date of inclusion is systematically delayed for ≥10% of the registrants in general and for ≥30% of the inclusions before 1997 in particular. This bias is enhanced for ascertainment by chiropody services and by frequent measurements of blood glucose because the date of reimbursement of services, rather than the date of encounter, has been taken as the date of inclusion in NDR. We also find that some 20% of the registrations in NDR may represent false positive inclusions of persons with frequent measurements of blood glucose without having diabetes. We conclude that NDR is a novel initiative to support research in the epidemiological and public health aspects of diabetes in Denmark, but we also present a list of recommended changes for improving validity, by reducing the impact of current sources of bias and misclassifications. PMID:25565889

  11. 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.

  12. Direct and indirect effects of seastars Asterias rubens on mussel beds ( Mytilus edulis) in the Wadden Sea

    NASA Astrophysics Data System (ADS)

    Saier, Bettina

    2001-08-01

    Near the island of Sylt in the Wadden Sea (German Bight, North Sea), seastars Asterias rubens (L.) co-occur with their preferred prey, mussels Mytilus edulis (L.), which form extensive beds from the intertidal down to the subtidal zone. Mussel density within these beds is significantly lower in the subtidal than the intertidal zone. Laboratory and field experiments were conducted to check if this was due to seastar predation. Feeding experiments did not indicate size refuge of M. edulis from predation by A. rubens, but showed that seastars preferred clean subtidal mussels above barnacle-overgrown intertidal ones. This preference coincided with higher abundances of both large ( arm length >5.5 cm) and smaller seastars in the shallow subtidal, but their abundance was too low to account for the decreased subtidal mussel density in the area studied. However, seastars may indirectly reduce mussel recruitment in the subtidal zone. This is caused by juvenile seastar predation upon the barnacles that grow on mussels, because such epigrowth strongly enhances recruitment in mussels. Such an indirect effect on mussel recruitment may affect mussel density more than adult seastar predation. An exception may be mass invasions of A. rubens on subtidal mussel beds. One such event happened during this study, clearing a large patch of mussels.

  13. Hazards of solar blue light

    SciTech Connect

    Okuno, Tsutomu

    2008-06-01

    Short-wavelength visible light (blue light) of the Sun has caused retinal damage in people who have stared fixedly at the Sun without adequate protection. The author quantified the blue-light hazard of the Sun according to the International Commission on Non-Ionizing Radiation Protection (ICNIRP) guidelines by measuring the spectral radiance of the Sun. The results showed that the exposure limit for blue light can be easily exceeded when people view the Sun and that the solar blue-light hazard generally increases with solar elevation, which is in accordance with a model of the atmospheric extinction of sunlight. Viewing the Sun can be very hazardous and therefore should be avoided except at very low solar elevations.

  14. Environmental concentrations of 3,4-methylenedioxymethamphetamine (MDMA)-induced cellular stress and modulated antioxidant enzyme activity in the zebra mussel.

    PubMed

    Parolini, Marco; Magni, Stefano; Binelli, Andrea

    2014-09-01

    Recent monitoring studies showed measurable levels of the 3,4-methylenedioxymethamphetamine (MDMA) in aquatic environments. However, no information is currently available on its potential hazard to aquatic non-target organisms. The aim of this study was to investigate the potential sub-lethal effects induced by 14-day exposures to low MDMA concentrations (0.05 and 0.5 μg/L) to zebra mussel (Dreissena polymorpha) specimens through the application of a biomarker suite. The trypan blue exclusion method and the neutral red retention assay (NRRA) were used to assess MDMA cytotoxicity. The activity of superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GPx), and glutathione S-transferase (GST), as well as the lipid peroxidation (LPO) and protein carbonyl content (PCC), were measured as oxidative stress indexes. The single cell gel electrophoresis (SCGE) assay, the DNA diffusion assay, and the micronucleus test (MN test) were applied to investigate DNA damage, while filtration rate was measured as physiological parameter. Despite significant decrease in lysosome membrane stability, hemocyte viability and imbalances in CAT and GST activities pointed out at the end of the exposure to 0.5 μg/L, no significant variations for the other end points were noticed at both the treatments, suggesting that environmentally relevant MDMA concentrations did not induce deleterious effects to the zebra mussel. PMID:24878561

  15. Two simple models for accounting mussel contamination with diarrhoetic shellfish poisoning toxins at Aveiro lagoon: Control by rainfall and atmospheric forcing

    NASA Astrophysics Data System (ADS)

    Vale, Paulo

    2012-02-01

    At Aveiro lagoon (Portuguese northwest coast) bivalve contamination with diarrhoetic shellfish poisoning toxins (DSTs), okadaic acid (OA) and dinophysistoxin-2 (DTX2), is a recurrent annual phenomenon seriously affecting seafood safety. The influence of meteorological parameters was studied to understand accumulation of DSTs in mussels, related to the blooming of the causative toxic microalgae, belonging to genus Dinophysis. Two simplified models were useful in predicting the accumulation of DSTs in blue mussels from this lagoon. Either the May river drainage or the rainfall accumulated from January through May could adequately predict the severity of OA accumulated from predation upon Dinophysis acuminata during June/July. In both cases a linear relationship was obtained, with correlation coefficients of 0.85 or greater. Winds with a west direction favour coastal concentration of Dinophysis acuta in Aveiro region. Both OA and DTX2 contamination increased exponentially in September/October with the cumulative number of days with W-wind orientation in the preceding August (correlation coefficients greater than 0.92). This relationship was attributed to the quadratic effect of wind stress on surface currents. August is a transitional month, when the continental runoff effect upon Dinophysis acuminata can still be observed and Dinophysis acuta advection may be promoted by westerly winds occurring in July. The frequency of periods with northerly winds in July can halt accumulation of toxins derived from Dinophysis acuta.

  16. 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. PMID:26806209

  17. Assimilation and depuration of microcystin-LR by the zebra mussel, Dreissena polymorpha.

    PubMed

    Pires, L M Dionisio; Karlsson, K M; Meriluoto, J A O; Kardinaal, E; Visser, P M; Siewertsen, K; Donk, E Van; Ibelings, B W

    2004-09-20

    Zebra mussels (Dreissena polymorpha) are an important component of the foodweb of shallow lakes in the Netherlands, amongst others in Lake IJsselmeer, an international important wetland. Large numbers of ducks feed on these mussels in autumn and winter. The mussels are filter feeders and are exposed to high densities of cyanobacteria in summer and autumn. Mussels and cyanobacteria both thrive in Lake IJsselmeer. Apparently the mussels are somehow protected against accumulation of harmful quantities of cyanobacterial toxins. In this study, we investigated the assimilation of the cyanobacterial toxin microcystin-LR (MC-LR) in zebra mussels when fed the toxic cyanobacterium Microcystis aeruginosa as sole food or in a mixture with the eustigmatophyte Nannochloropsis limnetica. After 3 weeks of assimilation we studied the depuration of MC-LR during 3 weeks when the food of the mussels was free of cyanobacteria. These assimilation/depuration experiments were combined with grazing experiments, using the same food treatments. Microcystins were analyzed using liquid chromatography-mass spectrometry (LC-MS); in addition, covalently bound MC were analyzed using the MMPB method. The mussels showed higher clearance rates on Microcystis than on Nannochloropsis. No selective rejection of either phytoplankton species was observed in the excretion products of the mussels. Zebra mussels fed Microcystis as single food, assimilated microcystin-LR relatively fast, and after 1 week the maximum value of free unbound microcystin assimilation (ca. 11 microg g DW(-1)) was attained. For mussels, fed with the mixed food, a maximum of only 3.9 microg g DW(-1) was recorded after 3 weeks. Covalently bound MC never reached high values, with a maximum of approximately 62% of free MC in the 2nd week of the experiment. In the depuration period microcystin decreased rapidly to low values and after 3 weeks only very low amounts of microcystin were detectable. The amount of toxin that accumulated in

  18. Assessing accumulation and sublethal effects of lead in a unionid mussel

    USGS Publications Warehouse

    Mosher, Shad; Cope, W. Gregory; Weber, Frank X.; Kwak, Thomas J.; Shea, Damian

    2012-01-01

    Lead (Pb) contamination of the environment remains a global problem. Previous studies have demonstrated that Pb deposited onto roadside sediments from the past use of leaded gasoline in vehicles may be mobilized into rivers and streams, thereby resulting in exposure to aquatic biota. The aims of this study were to conduct a 28-day laboratory toxicity test with Pb and adult Eastern Elliptio (Elliptio complanata; family Unionidae) mussels to determine uptake kinetics and to assess several potential non-lethal biomarkers of Pb exposure. Mussels were collected from a relatively uncontaminated reference site and exposed to a control and eight concentrations of Pb (as lead nitrate) ranging from 1 to 251 µg/L, as a static renewal test. There were five replicates per treatment with one mussel per replicate. The hemolymph of mussels from four of the replicates was repeatedly sampled (days 7, 14, 21, and 28) for analysis of Pb and ion (Na+, K+, Cl-, Ca2+) concentrations. The mussels in the fifth replicate per treatment were only sampled on day 28 and served as a comparison to the repeatedly sampled mussels. The accumulation of Pb in mussel tissue was also evaluated during the study. No mussels died during the test. We found that measured concentrations of Pb in mussel hemolymph suggested regulation of the heavy metal up to 66 μg/L by day 14, whereas concentrations in tissue proved to be strongly correlated (R2 = 0.98; p < 0.0001) throughout the 28-day exposure, displaying concentration dependent uptake. The concentration of Pb in mussel hemolymph, which can be sampled and measured non-lethally, is a suitable marker of recent Pb exposure in mussels. In contrast, none of the ion concentrations measured in the hemolymph from the repeatedly sampled mussels was significantly changed with increasing concentrations of Pb, whereas the mussels from the fifth replicate sampled only on day 28 showed altered calcium concentrations. The activity of δ-aminolevulinic acid dehydratase

  19. Mussel-inspired surface chemistry for multifunctional coatings.

    PubMed

    Lee, Haeshin; Dellatore, Shara M; Miller, William M; Messersmith, Phillip B

    2007-10-19

    We report a method to form multifunctional polymer coatings through simple dip-coating of objects in an aqueous solution of dopamine. Inspired by the composition of adhesive proteins in mussels, we used dopamine self-polymerization to form thin, surface-adherent polydopamine films onto a wide range of inorganic and organic materials, including noble metals, oxides, polymers, semiconductors, and ceramics. Secondary reactions can be used to create a variety of ad-layers, including self-assembled monolayers through deposition of long-chain molecular building blocks, metal films by electroless metallization, and bioinert and bioactive surfaces via grafting of macromolecules. PMID:17947576

  20. 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.

  1. Food habits of diving ducks in the Great Lakes after the zebra mussel invasion

    USGS Publications Warehouse

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

    1996-01-01

    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. Response of glutathione in mussels (Mytilus) exposed to common environmental contaminants

    SciTech Connect

    Inouye, L.S.; Casillas, E.

    1995-12-31

    Mussels (Mytilus sp.) were exposed to PCBs, a mixture of polycyclic aromatic hydrocarbons (PAHs), or extracts of contaminated sediments to determine the response of glutathione content in gill and digestive gland to chemicals contaminants. In addition, a field transplant investigation was conducted to determine if the differences observed in tissue glutathione levels of mussels from reference and contaminated sites were due to the presence of chemical contaminants rather than to population differences in basal glutathione concentrations. Exposure to PCBs or to sediment extracts from a contaminated site resulted in a decrease in glutathione content in the digestive gland, but an increase in glutathione content in gills. In contrast, no alterations in tissue glutathione were observed after exposure to PAHs. Transplant investigation results were consistent with those from the contaminated sediment extract exposure. Glutathione content in digestive glands was higher in mussels from a reference site compared to that found in mussels from the contaminated site, while the opposite trend was found in gill glutathione content of the same mussels. Eight weeks after being transplanted from the reference site to the contaminated site or alternatively from a contaminated site to a reference site, glutathione levels in the gland tissues matched those found in mussels native to the site to which they were transplanted. Although gill glutathione content was significantly different from that found at the site of origin, it did not match levels found in mussels native to the site to which they had been transplanted.

  3. Short-term effects of small dam removal on freshwater mussel assemblage

    USGS Publications Warehouse

    Heise, Ryan J.; Cope, W. Gregory; Kwak, Thomas J.; Eads, Chris B.

    2013-01-01

    Dam removal is increasingly used to restore lotic habitat and biota, but its effects on freshwater mussels (family Unionidae) are not well known. We conducted a four-year study to assess short-term effects on mussels after removal of a small hydropower dam on the Deep River (Cape Fear River drainage), North Carolina, USA, in 2006. We conducted annual pre- and post-removal monitoring of mussel density, richness, and survival (post removal only) with transect surveys and quadrat excavation, and assessed changes in substrate composition at two impact sites (tailrace and impoundment) and two reference sites. Before-after-control-impact (BACI) analyses of variance did not detect a significant change in mussel density (total or individually for the three most abundant species), species richness, Eastern Elliptio (Elliptio complanata) mean length, or substrate composition in the tailrace or drained impoundment following dam removal. Apparent annual survival estimates of Eastern Elliptio at the tailrace site did not differ among sampling periods and were similar to control sites. We observed minimal mussel mortality from stranding in the dewatered reservoir. These results demonstrate that adverse short-term impacts of dam removal on downstream mussel assemblages can be minimized with appropriate planning, timing, and removal techniques, but additional monitoring is warranted to determine long-term effects on mussels within the restored river reach.

  4. 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.

  5. Mussels: the forgotten fauna of regulated rivers: a case study of the Caney Fork River

    USGS Publications Warehouse

    Layzer, James B.; Gordon, Mark E.; Anderson, Robert M.

    1993-01-01

    During the past century freshwater mussel populations have declined precipitously throughout North America. Much of this loss has resulted from the construction of dams. In the Cumberland River system, 23% (22 species) of the historic mussel fauna is extinct or listed as endangered. Several additional species have either been extirpated from the Cumberland River or exist only in small, non-reproducing populations. Mussels of headwater streams have been severely affected by coal mining and poor land use practices. An intensive survey was conducted in the Caney Fork River, a major tributary to the Cumberland River, to determine the historic and extant mussel fauna. The results indicate that at least 37 species of mussels have been extirpated from the Caney Fork River, mainly as a result of the construction and operation of the Center Hill Dam. Among the species extirpated, two are now extinct, five are endangered and five are candidates for listing as threatened or endangered. Effects associated with this dam include the inundation of 102 km of riverine habitat, the discharge of hypolimnetic water (which limits mussel reproduction) and an alternating pattern of stream bed scouring and dewatering. The recognition of mussel life history requirements during preconstruction could have reduced many of these effects.

  6. Biomedical and Clinical Importance of Mussel-Inspired Polymers and Materials.

    PubMed

    Kaushik, Nagendra Kumar; Kaushik, Neha; Pardeshi, Sunil; Sharma, Jai Gopal; Lee, Seung Hyun; Choi, Eun Ha

    2015-11-01

    The substance secreted by mussels, also known as nature's glue, is a type of liquid protein that hardens rapidly into a solid water-resistant adhesive material. While in seawater or saline conditions, mussels can adhere to all types of surfaces, sustaining its bonds via mussel adhesive proteins (MAPs), a group of proteins containing 3,4-dihydroxyphenylalanine (DOPA) and catecholic amino acid. Several aspects of this adhesion process have inspired the development of various types of synthetic materials for biomedical applications. Further, there is an urgent need to utilize biologically inspired strategies to develop new biocompatible materials for medical applications. Consequently, many researchers have recently reported bio-inspired techniques and materials that show results similar to or better than those shown by MAPs for a range of medical applications. However, the susceptibility to oxidation of 3,4-dihydroxyphenylalanine poses major challenges with regard to the practical translation of mussel adhesion. In this review, various strategies are discussed to provide an option for DOPA/metal ion chelation and to compensate for the limitations imposed by facile 3,4-dihydroxyphenylalanine autoxidation. We discuss the anti-proliferative, anti-inflammatory, anti-microbial activity, and adhesive behaviors of mussel bio-products and mussel-inspired materials (MIMs) that make them attractive for synthetic adaptation. The development of biologically inspired adhesive interfaces, bioactive mussel products, MIMs, and arising areas of research leading to biomedical applications are considered in this review. PMID:26569266

  7. Biomedical and Clinical Importance of Mussel-Inspired Polymers and Materials

    PubMed Central

    Kaushik, Nagendra Kumar; Kaushik, Neha; Pardeshi, Sunil; Sharma, Jai Gopal; Lee, Seung Hyun; Choi, Eun Ha

    2015-01-01

    The substance secreted by mussels, also known as nature’s glue, is a type of liquid protein that hardens rapidly into a solid water-resistant adhesive material. While in seawater or saline conditions, mussels can adhere to all types of surfaces, sustaining its bonds via mussel adhesive proteins (MAPs), a group of proteins containing 3,4-dihydroxyphenylalanine (DOPA) and catecholic amino acid. Several aspects of this adhesion process have inspired the development of various types of synthetic materials for biomedical applications. Further, there is an urgent need to utilize biologically inspired strategies to develop new biocompatible materials for medical applications. Consequently, many researchers have recently reported bio-inspired techniques and materials that show results similar to or better than those shown by MAPs for a range of medical applications. However, the susceptibility to oxidation of 3,4-dihydroxyphenylalanine poses major challenges with regard to the practical translation of mussel adhesion. In this review, various strategies are discussed to provide an option for DOPA/metal ion chelation and to compensate for the limitations imposed by facile 3,4-dihydroxyphenylalanine autoxidation. We discuss the anti-proliferative, anti-inflammatory, anti-microbial activity, and adhesive behaviors of mussel bio-products and mussel-inspired materials (MIMs) that make them attractive for synthetic adaptation. The development of biologically inspired adhesive interfaces, bioactive mussel products, MIMs, and arising areas of research leading to biomedical applications are considered in this review. PMID:26569266

  8. Molecular characteristics and expression of calmodulin cDNA from the freshwater pearl mussel, Hyriopsis schlegelii.

    PubMed

    Zeng, L-G; Wang, J-H; Li, Y-J; Sheng, J-Q; Gu, Q; Hong, Y-J

    2012-01-01

    Calmodulin (CaM) is a multifunctional intracellular calcium ion receptor protein that participates in a range of cellular processes, including calcium metabolism in mussels. To investigate the role of CaM in freshwater mollusk shell calcium metabolism, the full-length CaM cDNA was isolated from the freshwater pearl mussel, Hyriopsis schlegelii (referred to as hsCaM) using SMART RACE technology. The full-length hsCaM was 855 bp in size, containing a 70-bp 5'-untranslated sequence, a 447-bp open reading frame, a 309-bp 3'-untranslated sequence, and a 26-nucleotide long poly(A) tail. The hsCaM mRNA expression in different mussel tissues was examined using real-time PCR. The hsCaM mRNA was found to be ubiquitously expressed, but far more abundant in the gill, foot, and mantle than in the posterior adductor muscle. Real-time PCR was also used to determine hsCaM mRNA expression levels in mantle tissues of H. schlegelii at different ages. No significant differences between one-, two-, and three-year-old mussels were detected, but expression increased in four-year-old mussels and then decreased in five-year-old mussels. CaM appears to be involved in calcium regulation of the mantle in four-year-old mussels, which may secrete more mother of pearl during pearl culture. PMID:22290464

  9. Characterization of metallothionein-like proteins from zebra mussels (Dreissena polymorpha)

    SciTech Connect

    High, K.A.; Barthet, V.J.; Blais, J.S.; McLaren, J.W.

    1997-06-01

    Zebra mussels (Dreissena polymorpha) are freshwater mollusks that have recently infested the Great Lakes ecosystem. Possessing a large capacity for filtration, these mussel populations act as bioconcentrators for contaminants, such as heavy metals, found in the Great Lakes ecosystem. Metallothionein is a low-molecular-weight, heavy metal-binding protein found in most living organisms. Characterization and partial purification of metallothionein-like Cd-binding proteins from zebra mussels were performed. Zebra mussels were exposed to 500 {micro}g/L Cd for 14 d. During the exposure period, two mussels were removed on alternate days for analysis of Cd-binding proteins. Gel-filtration high-performance liquid chromatography-microatomization-atomic absorption spectrophotometry results showed a single Cd-binding molecular weight protein fraction after 2 d of Cd exposure. After 10 d of Cd exposure, however, mussels exhibited an additional higher molecular weight, Cd-binding protein fraction. The lower molecular weight metallothionein-like Cd-binding protein was further isolated and purified by acetone fractionation, Sephadex G75, and diethylaminoethyl anion-exchange chromatography. The quantities of Zn, Cu, and Cd in the anion-exchange metallothionein-like protein isoforms were determined by inductively coupled plasma-mass spectrometry. The ability to bioconcentrate heavy metals in a metallothionein-like form coupled with their large population in the Great Lakes make zebra mussels suitable for use in a freshwater biomonitoring program for aquatic metal contamination.

  10. Studies of peripheral benzodiazepine receptors in mussels: comparison between a polluted and a nonpolluted site.

    PubMed

    Betti, Laura; Giannaccini, Gino; Nigro, Marco; Dianda, Sabina; Gremigni, Vittorio; Lucacchini, Antonio

    2003-01-01

    The aim of this study was to investigate the peripheral benzodiazepine receptors in soft tissue membranes of the mussel Mytilus galloprovincialis from both polluted and nonpolluted seawater populations, using a radioligand specific for this receptor, [3H]PK11195. Mussels were dissected into four body parts--mantle, gills, digestive gland, and muscles-to determine the distribution of tissue-specific peripheral benzodiazepine receptors (PBRs). The specific binding was saturable and reversible. A statistically significant increase (muscle, 537% and mantle, 201%, as absolute percentages) in the maximal number of binding sites (B(max)) was found in mussels from the polluted site, compared with mussels from the nonpolluted site. By contrast, the value of the dissociation constant (K(d)) at equilibrium does not show a statistically significant variation between the two groups. In competitive experiments of the compounds clonazepam, flumazenil, flunitrazepam, Ro5-4864, PK11195, and protoporphyrin IX, only PK11195 and protoporphyrin IX displaced [3H]PK11195 specifically bound to soft tissue membranes, revealing that the binding sites of peripheral benzodiazepine receptors of mussels have pharmacological properties comparable to those of low vertebrates such as trout. M. galloprovincialis was also tested as an indicator of heavy metal exposure, and metal accumulation in the digestive gland was measured by atomic absorption spectrophotometry (AAS). The contents of Pb, Mn, and Zn in mussels collected off the polluted site were higher than those in mussels from the nonpolluted site. These data suggest that PBRs are present in the soft tissues of the mussel M. galloprovincialis. Here we report preliminary evidence of biochemical alterations in mussels from the polluted site. PMID:12547633

  11. 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.

  12. Health risk assessments of heavy metal exposure via consumption of marine mussels collected from anthropogenic sites.

    PubMed

    Yap, Chee Kong; Cheng, Wan Hee; Karami, Ali; Ismail, Ahmad

    2016-05-15

    A total of 40 marine mussel Perna viridis populations collected (2002-2009) from 20 geographical sites located in two busy shipping lanes namely the Straits of Malacca (10 sites; 16 populations) and the Straits of Johore (8 sites; 21 populations) and three populations (2 sites) on the east coast of Peninsular Malaysia, was determined for Cd, Cu, Fe, Ni, Pb and Zn concentrations. In comparison with the maximum permissible limits (MPLs) set by existing food safety guidelines, all metal concentrations found in all the mussel populations were lower than the prescribed MPLs. In terms of the provisional tolerable weekly intake prescribed by the Joint FAO/WHO Expert Committee on Food Additives (JECFA) and oral reference doses (ORDs) by the USEPA, all the studied metals (except for Pb) were unlikely to become the limiting factors or unlikely to pose a risk for the consumption of the mussel populations. The estimated daily intake (EDI) for average level mussel (ALM) and high level mussel (HLM) consumers of mussels was found to be lower than the ORD guidelines for Cd, Cu, Fe, Ni and Zn. Furthermore, the target hazard quotient (THQ) was found to be less than 1 for ALM consumers but higher than 1 for HLM consumers in some sites. Therefore, there were no potential human health risks to the ALM consumers of the mussels. However, for Pb THQ values, the Pb levels in some mussel populations could create a health risk problem. Present results indicate that the consumption amounts of mussels should be limited for minimizing potential health risks of heavy metals to the HLM consumers. PMID:26925739

  13. 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

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

    USGS Publications Warehouse

    Starliper, Clifford E.

    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.

  15. Gender-specific metabolic responses in hepatopancreas of mussel Mytilus galloprovincialis challenged by Vibrio harveyi.

    PubMed

    Liu, Xiaoli; Sun, Hushan; Wang, Yiyan; Ma, Mengwen; Zhang, Yuemei

    2014-10-01

    Mussel Mytilus galloprovincialis is a marine aquaculture shellfish and frequently studied in shellfish immunology. In this work, the gender-specific metabolic responses induced by Vibrio harveyi in hepatopancreas from M. galloprovincialis were characterized using NMR-based metabolomics. In details, V. harveyi challenge increased the levels of amino acids including (valine, leucine, isoleucine, threonine, alanine, arginine and tyrosine) and ATP, and decreased the level of glucose in male mussel hepatopancreas. In V. harveyi-challenged female mussel hepatopancreas, both threonine and AMP were significantly elevated, and choline, phoshphocholine, sn-glycero-3-phosphocholine, taurine, betaine and ATP were depleted. Obviously, only threonine was similarly altered to that in V. harveyi-challenged male mussel hepatopancreas. These findings confirmed the gender-specific metabolic responses in mussels challenged by V. harveyi. Overall, V. harveyi induced an enhanced energy demand through activated glycolysis and immune response indicated by increased BCAAs in male mussel hepatopancreas. In female mussel hepatopancreas, V. harveyi basically caused disturbances in both osmotic regulation and energy metabolism through the metabolic pathways of conversions of phosphocholine and ADP to choline and ATP, and sn-glycero-3-phosphocholine and H2O into choline and sn-glycerol 3-phosphate. The altered mRNA expression levels of related genes (Cu/Zn-SOD, HSP90, lysozyme and defensin) suggested that V. harveyi induced obvious oxidative and immune stresses in both male and female mussel hepatopancreas. This work demonstrated that V. harveyi could induce gender-specific metabolic responses in mussel M. galloprovincialis hepatopancreas using NMR-based metabolomics. PMID:25123832

  16. 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

  17. Annoying Danish Relatives: Comprehension and Production of Relative Clauses by Danish Children with and without SLI

    ERIC Educational Resources Information Center

    Jensen De Lopez, Kristine; Olsen, Lone Sundahl; Chondrogianni, Vasiliki

    2014-01-01

    This study examines the comprehension and production of subject and object relative clauses (SRCs, ORCs) by children with Specific Language Impairment (SLI) and their typically developing (TD) peers. The purpose is to investigate whether relative clauses are problematic for Danish children with SLI and to compare errors with those produced by TD…

  18. Cryptosporidium parvum oocysts in zebra mussels (Dreissena polymorpha): evidence from the St Lawrence River.

    PubMed

    Graczyk, T K; Marcogliese, D J; de Lafontaine, Y; Da Silva, A J; Mhangami-Ruwende, B; Pieniazek, N J

    2001-03-01

    Molluscan shellfish can recover and concentrate environmentally derived waterborne pathogens and can be used for the sanitary assessment of water quality. Oocysts of Cryptosporidium parvum (genotype 1) were identified in zebra mussels (Dreissena polymorpha) from the St. Lawrence River, Quebec. Approximately 67 oocysts/ml of hemolymph and 129 oocysts/g of soft tissue were recovered. The adjusted concentration of oocysts per gram of tissue was 2.2 x 10(2), and approximately 4.4 x 10(2) oocysts were recovered from a single mussel. Zebra mussels can serve as biological indicators of waterborne contamination with Cryptosporidium. PMID:11293571

  19. 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. PMID:16902136

  20. Edward D. Goldberg's proposal of "the Mussel Watch": Reflections after 40years.

    PubMed

    Farrington, John W; Tripp, Bruce W; Tanabe, Shinsuke; Subramanian, Annamalai; Sericano, José L; Wade, Terry L; Knap, Anthony H

    2016-09-15

    We chronicle the extensive influence over the past forty years of Professor Edward D. Goldberg and his call in 1975 for a "Mussel Watch" or bivalve sentinel organism approach to assess geographic status and temporal trends of several chemicals of environmental concern in the coastal ocean. Examples of local, regional, national and international programs are discussed briefly as are examples of interesting useful findings and limitations to the Mussel Watch concept. Mussel Watch continues to provide useful data about status and trends of chemical contamination in coastal ecosystems. PMID:27339743

  1. 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

  2. Parenting among Wealthy Danish Families: A Concerted Civilising Process

    ERIC Educational Resources Information Center

    Bach, Dil

    2014-01-01

    This article explores the parenting practices of wealthy Danish families and offers insight into the workings of dominant parenting norms within contemporary Danish society. Based on ethnographic fieldwork conducted among 15 families living north of Copenhagen, Denmark, this article identifies the parenting strategies of people with ample…

  3. Statistical Learning in Emerging Lexicons: The Case of Danish

    ERIC Educational Resources Information Center

    Stokes, Stephanie F.; Bleses, Dorthe; Basboll, Hans; Lambertsen, Claus

    2012-01-01

    Purpose: This research explored the impact of neighborhood density (ND), word frequency (WF), and word length (WL) on the vocabulary size of Danish-speaking children. Given the particular phonological properties of Danish, the impact was expected to differ from that reported in studies on English and French. Method: The monosyllabic words in the…

  4. Educational Ambassadors in the Danish Trade Union Movement

    ERIC Educational Resources Information Center

    Keil, Michael

    2008-01-01

    The concept of Educational Ambassadors is embedded within the so-called "Danish model" of industrial relations. The Danish industrial relations system is characterised by strong collective organisations with national coverage, which conclude the collective agreements for various industries or sectors and which are mostly grouped under central…

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

    PubMed

    Peyer, Suzanne M; Hermanson, John C; Lee, Carol Eunmi

    2010-08-01

    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 difference are unknown. We examined whether quagga mussel shell morphology could be induced by three environmental variables through developmental plasticity. We predicted that shallow-water conditions (high temperature, food quantity, water motion) would yield a morphotype typical of wild quagga mussels from shallow habitats, while deep-water conditions (low temperature, food quantity, water motion) would yield a morphotype present in deep habitats. We tested this prediction by examining shell morphology and growth rate of quagga mussels collected from shallow and deep habitats and reared under common-garden treatments that manipulated the three variables. Shell morphology was quantified using the polar moment of inertia. Of the variables tested, temperature had the greatest effect on shell morphology. Higher temperature (approximately 18-20 degrees C) yielded a morphotype typical of wild shallow mussels regardless of the levels of food quantity or water motion. In contrast, lower temperature (approximately 6-8 degrees C) yielded a morphotype approaching that of wild deep mussels. If shell morphology has functional consequences in particular habitats, a plastic response might confer quagga mussels with a greater ability than zebra mussels to colonize a wider range of habitats within the Great Lakes. PMID:20639421

  6. Screening for celiac disease in Danish adults

    PubMed Central

    Horwitz, Anna; Skaaby, Tea; Kårhus, Line Lund; Schwarz, Peter; Jørgensen, Torben; Rumessen, Jüri J.; Linneberg, Allan

    2015-01-01

    Abstract Objective. The prevalence of celiac disease (CD) as recorded in the Danish National Patient Registry is ∼50/100,000 persons. This is much lower than the reported prevalence of CD in other Nordic countries and underdiagnosis is suspected. Our aim was to estimate the prevalence of CD in a population-based study of Danish adults. Methods. A total of 2297 adults aged 24–76 years living in the southwestern part of Copenhagen were screened for CD by immunoglobulin (Ig)A and IgG antibodies to transglutaminases and deamidated gliadin. IgA/IgG-positive participants were invited to a clinical evaluation, including biopsies, by a gastroenterologist. Results. Of the invited 56 participants, 40 underwent a full clinical evaluation and 8 persons were diagnosed with CD; 2 of the 16 persons, who did not complete the clinical evaluation, were considered by experts to have probable CD. None of the above 56 participants had a known history of CD or a recorded diagnosis of CD in National Patient Registry. By combining cases of biopsy-proven CD (n = 8), probable CD (n = 2), and registry-recorded CD (n = 1), the prevalence of CD was estimated to be 479/100,000 (11/2297) persons (95% CI: 197–761). Conclusion. In this general adult population, the prevalence of CD as estimated by screening and clinical evaluation was 10 times higher than the registry-based prevalence of CD. Of 11 participants diagnosed with CD in our screening study, 10 were unaware of the diagnosis prior to the study. Thus, our study suggests that CD is markedly underdiagnosed in Danish adults. PMID:25687734

  7. Toxic effects of cisplatin cytostatic drug in mussel Mytilus galloprovincialis.

    PubMed

    Trombini, Chiara; Garcia da Fonseca, Taina; Morais, Matilde; Rocha, Thiago Lopes; Blasco, Julián; Bebianno, Maria João

    2016-08-01

    Antineoplastic drugs used in chemotherapy were detected in aquatic environment: despite the very low concentrations (ng L(-1) to ug L(-1)), due to their potent mechanism of action they could have adverse effects on non-target aquatic organisms particularly under chronic exposure. Cisplatin (CDDP) is one of the most effective anticancer drug currently in use but information on its ecotoxicological effects is very limited. In this study, Mytilus galloprovincialis was used to investigate the toxic effects related to CDDP exposure. Mussels were exposed to cisplatin (100 ng L(-1)) for 14 days: antioxidant (superoxide dismutase, catalase, total and selenium-dependent glutathione peroxidase) and phase II (glutathione-S-transferase) enzymes activities, oxidative damage (lipid peroxidation), genotoxicity (DNA damage) and neurotoxicity (acetylcholinesterase) was evaluated. Results indicate that CDDP at tested concentration induce changes in the antioxidant capacity, oxidative stress in target organs (digestive gland and gills) as well as DNA damage in mussel hemocytes and neurotoxicity representing a risk for non-target organisms. PMID:27183200

  8. Complete male mitochondrial genomes of European Mytilus edulis mussels.

    PubMed

    Śmietanka, Beata; Wenne, Roman; Burzyński, Artur

    2016-05-01

    Doubly uniparental inheritance (DUI) results in the existence of two gender-specific, divergent mtDNA lineages within a single species. Under DUI, the female genome (F) is transmitted from mothers to the whole offspring, and the male genome (M) is transmitted exclusively from fathers to sons. This system was first described in a marine mussels Mytilus edulis inhabiting European coastal waters, over a decade ago. Despite that, the complete sequence of the M genome from the European M. edulis mussels remained unknown. Here we announce it for the first time. The announcement is based on the two haplotypes isolated from heteroplasmic males of European M. edulis sampled at two moderately distant locations: southern North Sea and western Baltic. The two M genomes are quite similar both in length (16,631 and 16,632 bp) and in sequence (98.3%). Furthermore, both newly sequenced genomes are closely related to the genomes described from Baltic M. trossulus. PMID:25208162

  9. Acute toxicity of cypermethrin on the freshwater mussel Unio gibbus.

    PubMed

    Khazri, Abdelhafidh; Sellami, Badreddine; Dellali, Mohamed; Corcellas, Cayo; Eljarrat, Ethel; Barceló, Damià; Mahmoudi, Ezzeddine

    2015-05-01

    Cypermethrin is a synthetic pyrethroid insecticide used worldwide in agriculture, home pest control, food stuff protection and disease vector control. We investigate the potential of cypermethrin to induce oxidative stress and enzyme activities within the gills of freshwater mussel Unio gibbus. This study was carried out under laboratory conditions using two nominal cypermethrin concentrations C1 (100µg/L) and C2 (150µg/L) during 96h. The measured concentrations of cypermethrin using GC-MS-MS in the treatment aquariums were respectively 59.7 µg/L and 97.5µg/L. Antioxidant enzyme activities (superoxide dismutase (SOD) and catalase (CAT)) as well as H2O2, malondialdehyde (MDA) and protein carbonyl (PCO) levels were assessed. An exposure during 96h induced the SOD activity at the highest concentration. The CAT activity and H2O2 level were increased significantly (P<0.05) in gills following a dose-dependent profile. Cypermethrin also generated an increase in malondialdehyde (MDA) levels reaching the highest value at the high concentration. The considered parameters can be used as biomarkers of exposure to cypermethrin. Freshwater mussel U. gibbus can be potentially employed in biomonitoring surveys of such threatened ecosystems. PMID:25681606

  10. Hepatitis E virus genotype 3 in mussels (Mytilus galloprovinciallis), Spain.

    PubMed

    Mesquita, João R; Oliveira, Danielle; Rivadulla, Enrique; Abreu-Silva, Joana; Varela, Miguel F; Romalde, Jesús L; Nascimento, Maria S J

    2016-09-01

    Coastal waters can become contaminated with both human waste from sewage treatment plants and runoff following manure application. Thus, shellfish produced close to land can bioaccumulate enteric viruses of human and animal origin, including zoonotic hepatitis E virus that infect both human and swine. The goal of this study was to evaluate the presence of HEV in shellfish from Galicia (NW Spain), a densely populated region with a strong tradition of swine farming, and one of the most important regions in the world for mussel production. We tested 81 mussel batches by RT-qPCR followed by conventional broad-spectrum nested RT-PCR and phylogenetic analysis. We have obtained 12 positive samples by RT-qPCR (14.81%) with HEV contamination levels ranging from 6.7 × 10(1) to 8.6 × 10(4) RNA copies/g digestive tissue. Phylogenetic analysis based on a 330 nt region of the ORF 1 showed that all sequenced isolates belonged to the zoonotic genotype 3 subgenotype e, being closely related to strains of human and swine origin. Results show that shellfish may be a potential route for HEV transmission to humans. PMID:27217353

  11. Phylogeography and systematics of zebra mussels and related species.

    PubMed

    Gelembiuk, Gregory W; May, Gemma E; Lee, Carol Eunmi

    2006-04-01

    The genus Dreissena includes two widespread and aggressive aquatic invaders, the zebra mussel, Dreissena polymorpha, and the quagga mussel, Dreissena bugensis. This genus evolved in the Ponto-Caspian Sea basin, characterized by dynamic instability over multiple timescales and a unique evolutionary environment that may predispose to invasiveness. The objectives of this study were to gain insights into the demographic history of Dreissena species in their endemic range, to reconstruct intraspecific phylogeographic relationships among populations, and to clarify systematics of the genus, using DNA sequences from the mitochondrial cytochrome oxidase I (COI) gene. We found four deeply diverged clades within this genus, with a basal split that approximately coincided with the Cretaceous-Tertiary boundary. Divergence events within the four base clades were much more recent, corresponding to geographically disjunct sets of populations, which might represent species complexes. Across all taxa, populations of Dreissena shared a common pattern of genetic signatures indicating historical population bottlenecks and expansions. Haplotype diversity was relatively low in Ponto-Caspian drainages relative to more stable tectonic lakes in Greece, Macedonia, and Turkey. The phylogeographic and demographic patterns in the endemic range of Dreissena might have resulted from vicariance events, habitat instability, and the high fecundity and passive dispersal of these organisms. PMID:16599965

  12. Behavioral responses of freshwater mussels to experimental dewatering

    USGS Publications Warehouse

    Galbraith, Heather S.; Blakeslee, Carrie J.; Lellis, William A.

    2015-01-01

    Understanding the effects of flow alteration on freshwater ecosystems is critical for predicting species responses and restoring appropriate flow regimes. We experimentally evaluated the effects of 3 dewatering rates on behavior of 6 freshwater mussel species in the context of water-removal rates observed in 21 Atlantic Coast rivers. Horizontal movement differed significantly among species and dewatering rates, but a significant species × dewatering interaction suggested that these factors influence movement in complex ways. Species differences in movement were evident only in controls and under slow dewatering rates, but these differences disappeared at moderate and fast dewatering rates. Burrowing behavior did not differ with respect to species identity or dewatering rate. The proportion of individuals that became stranded did not differ among species, but most individuals became stranded under low and moderate dewatering, and all individuals became stranded under fast dewatering. Mortality after stranding differed strongly among species along a gradient from 25% inPyganodon cataracta to 92% in Alasmidonta marginata. Together, these results suggest that species behavior may differ under gradual dewatering, but all species in our study are poorly adapted for rapid dewatering. Most of the 21 rivers we assessed experienced dewatering events comparable to our moderate rate, and several experienced events comparable to our fast rate. Dewatering events that exceed the movement or survival capability of most mussel species can be expected to result in assemblage-wide impacts. Consequently, the rate of water level change may be important in refining target flow conditions for restoration.

  13. Conservation genetics of North American freshwater mussels Amblema and Megalonaias

    USGS Publications Warehouse

    Mulvey, M.; Lydeard, C.; Pyer, D.L.; Hicks, K.M.; Brim-Box, J.; Williams, J.D.; Butler, R.S.

    1997-01-01

    Freshwater bivalves are among the most endangered groups of organisms in North America. Efforts to protect the declining mussel fauna are confounded by ambiguities associated with recognition of distinct evolutionary entities or species. This, in part, is due to the paucity of reliable morphological characters for differentiating taxa. We have employed allozymes and DNA sequence data to search for diagnosably distinct evolutionary entities within two problematic genera of unionid mussels, Amblema and Megalonaias. Within the genus Amblema three species are recognized based on our DNA sequence data for the mitochondrial 16S rRNA and allozyme data (Amblema neislerii, A. plicata, and A. elliotti). Only one taxonomically distinct entity is recognized within the genus Megalonaias—M. nervosa. Megalonaias boykiniana of the Apalachicolan Region is not diagnosable and does not warrant specific taxonomic status. Interestingly, Megalonaias from west of the Mississippi River, including the Mississippi, exhibited an allozyme and mtDNA haplotype frequency shift suggestive of an east-west dichotomy. The results of this study eliminate one subspecies of Amblema and increase the range of A. plicata. This should not affect the conservation status of “currently stable” assigned to A. plicata by Williams et al. (1993). The conservation status of A. elliotti needs to be reexamined because its distribution appears to be limited to the Coosa River System in Alabama and Georgia.

  14. Interpersonal violence: patterns in a Danish community.

    PubMed Central

    Hedeboe, J; Charles, A V; Nielsen, J; Grymer, F; Møller, B N; Møller-Madson, B; Jensen, S E

    1985-01-01

    We studied all cases of assault with violence (1,639) in a Danish population of 275,000 over a one-year period. Most victims were young men. The incidence rose during evenings, nights and weekends, and assaults were often seen in or around bars and restaurants. Women accounted for 64 per cent of all victims of assault in the home. Influence of alcohol was identified in 43 per cent of all cases. The fist was the most frequent agent of assault; use of firearms was a very rare act of violence but was associated with death in three out of five cases. There were 10 deaths in all. PMID:4003631

  15. Methylene blue related sterile endophthalmitis.

    PubMed

    Lim, A K E; Ulagantheran V, V; Siow, Y C; Lim, K S

    2008-08-01

    To report a case of methylene blue related endophthalmitis. Observational case report. Review of clinical record, photographs. A 60 year old man developed endophthalmitis after methylene blue was accidentally used to stain the anterior capsule during phacoemulsification of cataract. His left visual acuity deteriorated from 6/12 to 6/36 two weeks after the operation. Despite intensive treatment with topical and intravitreal antibiotics, his condition deteriorated. A vitrectomy and silicone oil injection eventually managed to control the progression of the disease and salvage the eye. However the visual outcome remained poor due to corneal decompensation and retinal ischemia. Both vitreous tap and vitreous biopsy were negative for any organism. Methylene blue is extremely toxic to ocular structures and should not be used intraocularly. PMID:19248701

  16. Developing and Evaluating a Multimodal Course Format: Danish for Knowledge Workers--Labour Market-Related Danish

    ERIC Educational Resources Information Center

    Frederiksen, Karen-Margrete; Laursen, Katja Årosin

    2015-01-01

    This paper presents our reflections on developing the Computer-Assisted Language Learning (CALL) course "Danish for knowledge workers--labour market-related Danish." As defined by Laursen and Frederiksen (2015), knowledge workers are "highly educated people who typically work at universities, at other institutions of higher…

  17. The blue-collar brain.

    PubMed

    Van Orden, Guy; Hollis, Geoff; Wallot, Sebastian

    2012-01-01

    Much effort has gone into elucidating control of the body by the brain, less so the role of the body in controlling the brain. This essay develops the idea that the brain does a great deal of work in the service of behavior that is controlled by the body, a blue-collar role compared to the white-collar control exercised by the body. The argument that supports a blue-collar role for the brain is also consistent with recent discoveries clarifying the white-collar role of synergies across the body's tensegrity structure, and the evidence of critical phenomena in brain and behavior. PMID:22719730

  18. Blue-green upconversion laser

    DOEpatents

    Nguyen, D.C.; Faulkner, G.E.

    1990-08-14

    A blue-green laser (450--550 nm) uses a host crystal doped with Tm[sup 3+]. The Tm[sup 3+] is excited through upconversion by a red pumping laser and an IR pumping laser to a state which transitions to a relatively lower energy level through emissions in the blue-green band, e.g., 450.20 nm at 75 K. The exciting laser may be tunable dye lasers or may be solid-state semiconductor laser, e.g., GaAlAs and InGaAlP. 3 figs.

  19. Crater Lake: blue through time

    USGS Publications Warehouse

    Larson, Gary L.; Buktenica, Mark; Collier, Robert

    2003-01-01

    Blue is the color of constancy, hence the term true blue. The unearthly blueness of Crater Lake reflects its pristine character and gives scientists a focal point for studying human impacts on aquatic environments over long periods of time. Scientists with the U.S. Geological Survey (USGS), National Park Service, and Oregon State University have systematically studied the lake for the last two decades. Long-term monitoring of this lake is a priority of Crater Lake National Park and will continue far into the future.

  20. The Blue-Collar Brain

    PubMed Central

    Van Orden, Guy; Hollis, Geoff; Wallot, Sebastian

    2012-01-01

    Much effort has gone into elucidating control of the body by the brain, less so the role of the body in controlling the brain. This essay develops the idea that the brain does a great deal of work in the service of behavior that is controlled by the body, a blue-collar role compared to the white-collar control exercised by the body. The argument that supports a blue-collar role for the brain is also consistent with recent discoveries clarifying the white-collar role of synergies across the body’s tensegrity structure, and the evidence of critical phenomena in brain and behavior. PMID:22719730