Science.gov

Sample records for meeting aquatic species

  1. 75 FR 61175 - Aquatic Nuisance Species Task Force Meeting

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-10-04

    ... Fish and Wildlife Service Aquatic Nuisance Species Task Force Meeting AGENCY: Fish and Wildlife Service... Species (ANS) Task Force. The meeting is open to the public. The meeting topics are identified in the SUPPLEMENTARY INFORMATION section. DATES: The ANS Task Force will meet from 8 a.m. to 5 p.m. on...

  2. 78 FR 60306 - Aquatic Nuisance Species Task Force Meeting

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-10-01

    ... implement a program for U.S. waters to prevent introduction and dispersal of aquatic invasive species (AIS... Snakehead and Lionfish Management Plans. Biocontrol Programs. National Invasive Species Awareness Week... Fish and Wildlife Service Aquatic Nuisance Species Task Force Meeting AGENCY: Fish and Wildlife...

  3. Proceedings of the Subcontractors' Review Meeting: Aquatic Species Program

    SciTech Connect

    Not Available

    1981-07-01

    The Aquatic Species Program (ASP) addresses the utilization of plant biomass that naturally occurs in wetland or submerged areas. Processes are being developed through this program to make use of such aquatic species, capitalizing on their inherent capacity for rapid growth as well as their extraordinary chemical compositions.

  4. Aquatic Species Program review: proceedings of principal investigators meeting

    SciTech Connect

    Not Available

    1985-06-01

    The purpose of the Aquatic Species Program is to improve the productivity, conversion to fuels, and cost efficiency of aquatic plant culture technologies. The emphasis of the program is on developing a mass culture technology for cultivating oil-yielding microalgae in the American southwest. A technical and economic analysis indicated that such a concept would be feasible if (1) lipid yields from microalgae are improved, (2) there is sufficient saline water for large-scale development, and (3) microalgal lipids can be economically converted to conventional fuels. It was determined that fuels from microalgal lipids presented better options than converting the microalgal biomass to either alcohols or methane. All lipids can potentially be catalytically converted to gasoline, or the fatty acids can be converted to substitute diesel fuels. The Southwest has the necessary low, flat, underutilized lands, and carbon dioxide is available from either natural deposits or flue gas from industrial plants. The amount of saline water available will probably determine how much fuel can be produced from aquatic species, and this question should be answered during 1985. The largest constraint of this technology is the economical production of an oil-rich microalgal feedstock. The agenda for the review was divided into four sections: species selection and characterization, applied physiological studies, outdoor mass cultivation, and systems design and analysis. Papers from these presentations are included in these proceedings. Program advances were reported in the areas of species collection and selection, modulated light physiology, mass culture yields, harvesting of microalgae, mass culture facility design and analysis, and assessments on fuel options from microalgae. Separate abstracts have been prepared for each paper for inclusion in the Energy Data Base.

  5. 77 FR 16256 - Aquatic Nuisance Species Task Force Meeting

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-03-20

    ... minutes on the ANS Task Force Web site at: http://anstaskforce.gov/meetings.php . FOR FURTHER INFORMATION... site at: http://anstaskforce.gov/meetings.php . Accessibility Information The meeting location...

  6. 77 FR 61019 - Aquatic Nuisance Species Task Force Meeting

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-10-05

    ....php . FOR FURTHER INFORMATION CONTACT: Susan Mangin, Executive Secretary, ANS Task Force, at (703) 358... site at: http://anstaskforce.gov/meetings.php . Accessibility Information The meeting location...

  7. 76 FR 60863 - Aquatic Nuisance Species Task Force Meeting

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-09-30

    .... You may also view the minutes on the ANS Task Force Web site at http://anstaskforce.gov/meetings.php... Task Force Web site at http://anstaskforce.gov/meetings.php . Accessibility Information The...

  8. 75 FR 15457 - Aquatic Nuisance Species Task Force Meeting

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-03-29

    ... Task Force Web site at: http://anstaskforce.gov/meetings.php . FOR FURTHER INFORMATION CONTACT: Susan... on the ANS Task Force Web site at: http://anstaskforce.gov/meetings.php . Dated: March 19,...

  9. 76 FR 15334 - Aquatic Nuisance Species Task Force Meeting

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-03-21

    ... minutes on the ANS Task Force Web site at: http://anstaskforce.gov/meetings.php . FOR FURTHER INFORMATION... on the ANS Task Force Web site at: http://anstaskforce.gov/meetings.php . Dated: March 14,...

  10. Aquatic Species Program Review: Proceedings of the March 1983 Principal Investigators Meeting

    SciTech Connect

    Not Available

    1983-06-01

    The Aquatic Species Program (ASP) addresses the utilization of plant biomass that naturally occurs in wetland or submerged areas. Processes are being developed through this program to make use of such aquatic species, capitalizing on their inherent capacity for rapid growth as well as their extraordinary chemical compositions.

  11. Abstracts of Presentation: Aquatic Species Program Annual Review Meeting, Golden, Colorado, 24-25 September 1986

    SciTech Connect

    Not Available

    1986-09-01

    The goal of the aquatic species program is to produce gasoline and diesel fuels from microalgae grown in saline waters of the desert southwest. Microalgae are known to accumulate lipids in large quantities and can thrive in high salinity water which currently has no other use.

  12. Aquatic invasive species

    USGS Publications Warehouse

    Thorsteinson, Lyman

    2005-01-01

    Invasive species are plants or animals that are present in an ecosystem beyond their native range. They may have few natural controls in their new environment and proliferate. They can threaten native species and interfere with human activities. The Western Fisheries Research Center (WFRC) has been conducting research to understand how non-native species invade and affect ecosystems, thus aiding management efforts.

  13. Proceedings of the SERI Biomass Program Principal Investigators' Review Meeting: Aquatic Species Program Reports; 23-25 June 1982, Washington, DC

    SciTech Connect

    Not Available

    1982-12-01

    The Aquatic Species Program (ASP) is concerned with how plant biomass that naturally occurs in wetland or submerged areas is utilized. Processes are being developed in this program to make use of those aquatic species, capitalizing on their inherent capacity for rapid growth as well as on their extraordinary chemical compositions.

  14. Dicer Functions in Aquatic Species

    PubMed Central

    Kitagishi, Yasuko; Okumura, Naoko; Yoshida, Hitomi; Tateishi, Chika; Nishimura, Yuri; Matsuda, Satoru

    2011-01-01

    Dicer is an RNase III enzyme with two catalytic subunits, which catalyzes the cleavage of double-stranded RNA to small interfering RNAs and micro-RNAs, which are mainly involved in invasive nucleic acid defense and endogenous genes regulation. Dicer is abundantly expressed in embryos, indicating the importance of the protein in early embryonic development. In addition, Dicer is thought to be involved in defense mechanism against foreign nucleic acids such as viruses. This paper will mainly focus on the recent progress of Dicer-related research and discuss potential RNA interference pathways in aquatic species. PMID:22312469

  15. The National Nonindigenous Aquatic Species Program

    USGS Publications Warehouse

    Pawlitz, Rachel J.; David, Kayla D.

    2012-01-01

    The U.S. Geological Survey (USGS) Nonindigenous Aquatic Species (NAS) Program monitors, analyzes, and records sightings of non-native (introduced) aquatic species throughout the United States. The program is based at the USGS Southeast Ecological Science Center in Gainesville, Florida. The initiative to maintain scientific information on nationwide occurrences of non-native aquatic species began with the Aquatic Nuisance Species Task Force, a group created by Congress in 1990 to address the need for this type of information by natural resource managers. Since then, the NAS program has maintained the database as a clearinghouse of information for confirmed sightings of non-native aquatic species throughout the Nation. The program also produces email alerts, maps, summary graphs, publications, and other information products to support natural resource managers.

  16. Aquatic invasive species: Lessons from cancer research

    USGS Publications Warehouse

    Sepulveda, Adam; Ray, Andrew; Al-Chokhachy, Robert K.; Muhlfeld, Clint C.; Gresswell, Robert E.; Gross, Jackson A.; Kershner, Jeffrey L.

    2014-01-01

    Aquatic invasive species are disrupting ecosystems with increasing frequency. Successful control of these invasions has been rare: Biologists and managers have few tools for fighting aquatic invaders. In contrast, the medical community has long worked to develop tools for preventing and fighting cancer. Its successes are marked by a coordinated research approach with multiple steps: prevention, early detection, diagnosis, treatment options and rehabilitation. The authors discuss how these steps can be applied to aquatic invasive species, such as the American bullfrog (Lithobates catesbeianus), in the Northern Rocky Mountain region of the United States, to expedite tool development and implementation along with achievement of biodiversity conservation goals.

  17. Estimation of inorganic species aquatic toxicity

    USGS Publications Warehouse

    Hickey, James P.; Ostrander, Gary K.

    2005-01-01

    The acute aquatic toxicities (narcoses) for a range of organism types may be estimated with LSER for a large number of inorganic and organometal species, many with an accuracy at or within an order of magnitude. Optimum estimations make use of a bioavailable metal fraction and a more accurate structure(s) for the toxic solution species. The estimated toxicities for a number of salts were quite different from the observed values, likely due to a dominant specific toxicity mechanism other than baseline narcosis. The tool still requires fine-tuning.

  18. Persistent toxic substances in Mediterranean aquatic species.

    PubMed

    Miniero, Roberto; Abate, Vittorio; Brambilla, Gianfranco; Davoli, Enrico; De Felip, Elena; De Filippis, Stefania P; Dellatte, Elena; De Luca, Silvia; Fanelli, Roberto; Fattore, Elena; Ferri, Fabiola; Fochi, Igor; Rita Fulgenzi, Anna; Iacovella, Nicola; Iamiceli, Anna Laura; Lucchetti, Dario; Melotti, Paolo; Moret, Ivo; Piazza, Rossano; Roncarati, Alessandra; Ubaldi, Alessandro; Zambon, Stefano; di Domenico, Alessandro

    2014-10-01

    Fish and fishery products may represent one of the main sources of dietary exposure to persistent toxic substances (PTSs) such as polychlorinated dibenzodioxins, dibenzofurans, and biphenyls; polybromodiphenyl ethers; organochlorine pesticides; perfluorooctanoic acid and perfluorooctane sulfonate; and inorganic mercury and methyl mercury. In this study, PTS contamination of Mediterranean fish and crustaceans caught in Italian coastal waters was investigated in order to increase the representativeness of the occurrence database for wild species. The objectives were to verify the suitability of regulatory limits for PTSs, identify background concentrations values, if any, and examine the possible sources of variability when assessing the chemical body burdens of aquatic species. Twelve wild species of commercial interest and two farmed fish species were chosen. Excluding methyl mercury, chemical concentrations found in wild species fell generally towards the low ends of the concentration ranges found in Europe according to EFSA database and were quite lower than the tolerable maximum levels established in the European Union; farmed fish always showed contamination levels quite lower than those detected in wild species. The data obtained for wild species seemed to confirm the absence of local sources of contamination in the chosen sampling areas; however, species contamination could exceed regulatory levels even in the absence of specific local sources of contamination as a result of the position in the food web and natural variability in species' lifestyle. A species-specific approach to the management of contamination in aquatic organisms is therefore suggested as an alternative to a general approach based only on contaminant body burden. A chemical-specific analysis performed according to organism position in the food chain strengthened the need to develop this approach. PMID:25020099

  19. Persistent toxic substances in Mediterranean aquatic species.

    PubMed

    Miniero, Roberto; Abate, Vittorio; Brambilla, Gianfranco; Davoli, Enrico; De Felip, Elena; De Filippis, Stefania P; Dellatte, Elena; De Luca, Silvia; Fanelli, Roberto; Fattore, Elena; Ferri, Fabiola; Fochi, Igor; Rita Fulgenzi, Anna; Iacovella, Nicola; Iamiceli, Anna Laura; Lucchetti, Dario; Melotti, Paolo; Moret, Ivo; Piazza, Rossano; Roncarati, Alessandra; Ubaldi, Alessandro; Zambon, Stefano; di Domenico, Alessandro

    2014-10-01

    Fish and fishery products may represent one of the main sources of dietary exposure to persistent toxic substances (PTSs) such as polychlorinated dibenzodioxins, dibenzofurans, and biphenyls; polybromodiphenyl ethers; organochlorine pesticides; perfluorooctanoic acid and perfluorooctane sulfonate; and inorganic mercury and methyl mercury. In this study, PTS contamination of Mediterranean fish and crustaceans caught in Italian coastal waters was investigated in order to increase the representativeness of the occurrence database for wild species. The objectives were to verify the suitability of regulatory limits for PTSs, identify background concentrations values, if any, and examine the possible sources of variability when assessing the chemical body burdens of aquatic species. Twelve wild species of commercial interest and two farmed fish species were chosen. Excluding methyl mercury, chemical concentrations found in wild species fell generally towards the low ends of the concentration ranges found in Europe according to EFSA database and were quite lower than the tolerable maximum levels established in the European Union; farmed fish always showed contamination levels quite lower than those detected in wild species. The data obtained for wild species seemed to confirm the absence of local sources of contamination in the chosen sampling areas; however, species contamination could exceed regulatory levels even in the absence of specific local sources of contamination as a result of the position in the food web and natural variability in species' lifestyle. A species-specific approach to the management of contamination in aquatic organisms is therefore suggested as an alternative to a general approach based only on contaminant body burden. A chemical-specific analysis performed according to organism position in the food chain strengthened the need to develop this approach.

  20. Aquatic species project report: FY 1991

    SciTech Connect

    Brown, L.M.; Sprague, S.

    1992-04-01

    This report summarizes the progress and research accomplishments of the Aquatic Species Project, which is managed by the National Renewable Energy Laboratory for the US Department of Energy. The project is focused on applying genetic engineering techniques to enhance the lipid, or oil, production of microalgae. Those lipids can be extracted and processed into high-energy liquid fuels such as diesel. Because microalgae require carbon dioxide, a major ``greenhouse`` gas, as a nutrient, project researchers also study the role that microalgae could play in a possible global climate change mitigation strategy.

  1. Aquatic species project report: FY 1991

    SciTech Connect

    Brown, L.M. ); Sprague, S. )

    1992-04-01

    This report summarizes the progress and research accomplishments of the Aquatic Species Project, which is managed by the National Renewable Energy Laboratory for the US Department of Energy. The project is focused on applying genetic engineering techniques to enhance the lipid, or oil, production of microalgae. Those lipids can be extracted and processed into high-energy liquid fuels such as diesel. Because microalgae require carbon dioxide, a major greenhouse'' gas, as a nutrient, project researchers also study the role that microalgae could play in a possible global climate change mitigation strategy.

  2. ESTIMATION OF AQUATIC SPECIES SENSITIVITY AND POPULATION-LEVEL RESPONSES

    EPA Science Inventory

    Determining species sensitivity and population-level responses of aquatic organisms to contaminants are critical components of criteria development and ecological risk assessment. To address data gaps in species sensitivity, the U.S. EPA developed the Interspecies Correlation Est...

  3. FY 1987 Aquatic Species Program: Annual report

    SciTech Connect

    Johnson, D.A.; Sprague, S.

    1987-09-01

    The goal of the Department of Energy/Solar Energy Research Institute Aquatic Species Program is to develop the technology base to produce liquid fuels from microalagae at prices competitive with conventional alternatives. Microalgae are unusual plants that can accumulate large quantities of oil and can thrive in high-salinity water, which currently has no competing uses. The algal oils, in turn, are readily converted into gasoline and diesel fuels. The best site for successful microalgae production was determined to be the US desert Southwest, with potential applications to other warm areas. Aggressive research is needed, but the improvements required are attainable. The four prime research areas in the development of this technology are growth and production, engineering design, harvesting, and conversion. Algae are selected for three criteria: tolerance to environmental fluctuations, high growth rates, and high lipid production. From 1982 to 1986, the program collected more than 3000 strains of microalgae that are more than twice as tolerant to temperature and salinity fluctuation than the initial strains. Productivity has been increased by a factor of two in outdoor culture systems since 1982, and lipid content has also been increased from 20% of body weight in 1982 to greater than 66% of body weight in 1987. Research programs are ongoing in lipid biochemistry and genetic engineering so that ultimately strains can be modified and improved to combine their best characteristics. An outdoor test facility is being built in Roswell, New Mexico.

  4. Mapping, Monitoring and Modeling Submersed Aquatic Vegetation Species and Communities

    NASA Astrophysics Data System (ADS)

    Hartis, Brett Michael

    Aquatic macrophyte communities are critically important habitat species in aquatic systems worldwide. None are more important than those found beneath the water's surface, commonly referred to as submersed aquatic vegetation (SAV). Although vital to such systems, many native submersed plants have shown near irreversible declines in recent decades as water quality impairment, habitat destruction, and encroachment by invasive species have increased. In the past, aquatic plant science has emphasized the restoration and protection of native species and the management of invasive species. Comparatively little emphasis has been directed toward adequately mapping and monitoring these resources to track their viability over time. Modeling the potential intrusion of certain invasive plant species has also been given little attention, likely because aquatic systems in general can be difficult to assess. In recent years, scientists and resource managers alike have begun paying more attention to mapping SAV communities and to address the spread of invasive species across various regions. This research attempts to provide new, cutting-edge techniques to improve SAV mapping and monitoring efforts in coastal regions, at both community and individual species levels, while also providing insights about the establishment potential of Hydrilla verticillata, a noxious, highly invasive submersed plant. Technological advances in satellite remote sensing, interpolation and spatial analysis in geographic information systems, and state-of-the-art climate envelope modeling techniques were used to further assess the dynamic nature of SAV on various scales. This work contributes to the growing science of mapping, monitoring, and modeling of SAV

  5. Environmental Effects of BPA: Focus on Aquatic Species.

    PubMed

    Canesi, Laura; Fabbri, Elena

    2015-01-01

    Research on bisphenol A (BPA) as an environmental contaminant has now major regulatory implications toward the ecosystem health, and hence it is incumbent on scientists to do their research to the highest standards possible, in order that the most appropriate decisions are made to mitigate the impacts to aquatic wildlife. However, the contribution given so far appears rather fragmented. The present overview aims to collect available information on the effects of BPA on aquatic vertebrates and invertebrates to provide a general scenario and to suggest future developments toward more comprehensive approaches useful for aquatic species protection. PMID:26674307

  6. Molecular Species Delimitation and Morphology of Aquatic and Sub-Aquatic Bugs (Heteroptera) in Cameroon.

    PubMed

    Meyin A Ebong, Solange; Petit, Elsa; Le Gall, Philippe; Chen, Ping-Ping; Nieser, Nico; Guilbert, Eric; Njiokou, Flobert; Marsollier, Laurent; Guégan, Jean-François; Pluot-Sigwalt, Dominique; Eyangoh, Sara; Harry, Myriam

    2016-01-01

    Aquatic and semi-aquatic bugs (Heteroptera) represent a remarkable diversity and a resurging interest has been given to documenting at the species level these insects inhabiting Cameroon in Central Africa due to their potential implication in the transmission of the bacterium Mycobacterium ulcerans, the causal agent of Buruli ulcer, an emerging human disease. A survey was carried out over two years in Cameroon. Morphological analyses were done in two steps. A first step consisted in separating the specimens based on broadly shared characters into morphotypes. The specimens were then separated into two independent batches containing each the same representation of each morphotype. One batch (309 specimens) was used by taxonomy experts on aquatic bugs for species level identification and/or to reconcile nymph with their corresponding adult species. The second batch (188 specimens) was used to define species based on the COI DNA sequences (standard sequence used for "DNA barcoding") and using the Automatic Barcode Gap Discovery (ABGD) method. The first morphological analysis step separated the specimens into 63 different morphotypes (49 adults and 14 nymphs), which were then found to belong to 54 morphological species in the infra-orders Gerromorpha and Nepomorpha based on the species-level morphological identification, and 41-45 putative molecular species according to the gap value retained in the ABGD. Integrating morphology and "DNA barcoding" reconciled all the specimens into 62 aquatic bug species in Cameroon. Generally, we obtained a good congruence between species a priori identified based on morphology from adult morphotypes and molecular putative species. Moreover, molecular identification has allowed the association of 86% of nymphs with adults. This work illustrates the importance of integrative taxonomy.

  7. Molecular Species Delimitation and Morphology of Aquatic and Sub-Aquatic Bugs (Heteroptera) in Cameroon

    PubMed Central

    Le Gall, Philippe; Chen, Ping-Ping; Nieser, Nico; Guilbert, Eric; Njiokou, Flobert; Marsollier, Laurent; Guégan, Jean-François; Pluot-Sigwalt, Dominique; Eyangoh, Sara; Harry, Myriam

    2016-01-01

    Aquatic and semi-aquatic bugs (Heteroptera) represent a remarkable diversity and a resurging interest has been given to documenting at the species level these insects inhabiting Cameroon in Central Africa due to their potential implication in the transmission of the bacterium Mycobacterium ulcerans, the causal agent of Buruli ulcer, an emerging human disease. A survey was carried out over two years in Cameroon. Morphological analyses were done in two steps. A first step consisted in separating the specimens based on broadly shared characters into morphotypes. The specimens were then separated into two independent batches containing each the same representation of each morphotype. One batch (309 specimens) was used by taxonomy experts on aquatic bugs for species level identification and/or to reconcile nymph with their corresponding adult species. The second batch (188 specimens) was used to define species based on the COI DNA sequences (standard sequence used for “DNA barcoding”) and using the Automatic Barcode Gap Discovery (ABGD) method. The first morphological analysis step separated the specimens into 63 different morphotypes (49 adults and 14 nymphs), which were then found to belong to 54 morphological species in the infra-orders Gerromorpha and Nepomorpha based on the species-level morphological identification, and 41–45 putative molecular species according to the gap value retained in the ABGD. Integrating morphology and “DNA barcoding” reconciled all the specimens into 62 aquatic bug species in Cameroon. Generally, we obtained a good congruence between species a priori identified based on morphology from adult morphotypes and molecular putative species. Moreover, molecular identification has allowed the association of 86% of nymphs with adults. This work illustrates the importance of integrative taxonomy. PMID:27149077

  8. SERI Aquatic Species Program: 1983 Annual Report

    SciTech Connect

    Not Available

    1984-03-01

    During 1983 research was carried out under three tasks: biological, engineering, and analysis. Biological research was aimed at screening for promising species of microalgae, macroalgae, and emergent plants that could be cultivated for energy products. Promising species were studied further to improve yields.

  9. Aquatic invasive species harming U.S. ecosystems, fisheries

    NASA Astrophysics Data System (ADS)

    Showstack, Randy

    Biological invasions are fundamentally changing the structure and function of many ecosystems around the world, Gregory Ruiz, senior scientist with the Smithsonian Environmental Research Center in Edgewater, Maryland, told a 20 June U.S. Congressional hearing on aquatic invasive species."Not only have many [nuisance aquatic species] become established, but many communities are now dominated by [them] in terms of number or organisms, biomass, and ecological processes," Ruiz said. "In some cases, it is clear that invasions have caused dramatic shifts in food webs, chemical cycling, disease outbreaks, and commercial fisheries."

  10. Aquatic invasive species harming U.S. ecosystems, fisheries

    NASA Astrophysics Data System (ADS)

    Showstack, Randy

    Biological invasions are fundamentally changing the structure and function of many ecosystems around the world, Gregory Ruiz, senior scientist with the Smithsonian Environmental Research Center in Edgewater, Maryland, told a 20 June U.S. Congressional hearing on aquatic invasive species.“Not only have many [nuisance aquatic species] become established, but many communities are now dominated by [them] in terms of number or organisms, biomass, and ecological processes,” Ruiz said. “In some cases, it is clear that invasions have caused dramatic shifts in food webs, chemical cycling, disease outbreaks, and commercial fisheries.”

  11. Induced pluripotent stem cell technology and aquatic animal species.

    PubMed

    Temkin, Alexis M; Spyropoulos, Demetri D

    2014-06-01

    Aquatic animal species are the overall leaders in the scientific investigation of tough but important global health issues, including environmental toxicants and climate change. Historically, aquatic animal species also stand at the forefront of experimental biology, embryology and stem cell research. Over the past decade, intensive and high-powered investigations principally involving mouse and human cells have brought the generation and study of induced pluripotent stem cells (iPSCs) to a level that facilitates widespread use in a spectrum of species. A review of key features of these investigations is presented here as a primer for the use of iPSC technology to enhance ongoing aquatic animal species studies. iPSC and other cutting edge technologies create the potential to study individuals from "the wild" closer to the level of investigation applied to sophisticated inbred mouse models. A wide variety of surveys and hypothesis-driven investigations can be envisioned using this new capability, including comparisons of organism-specific development and exposure response and the testing of fundamental dogmas established using inbred mice. However, with these new capabilities, also come new criteria for rigorous baseline assessments and testing. Both the methods for inducing pluripotency and the source material can negatively impact iPSC quality and bourgeoning applications. Therefore, more rigorous strategies not required for inbred mouse models will have to be implemented to approach global health issues using individuals from "the wild" for aquatic animal species.

  12. Aquatic Species Project report, FY 1989--1990

    SciTech Connect

    Brown, L.M.; Sprague, S.

    1992-01-01

    This report summarizes the progress and research accomplishments of the Aquatic Species Project. The four articles included are summaries of individual research projects and are entered into the EDB as such. The goal of the Aquatic Species Project is to develop the technology base for large-scale production of oil-rich microalgae. The project is also developing methods to convert the microalgal lipids into liquid fuels needed for industry and transportation. Researchers in the Aquatics Species Project focus on the use of microalgae as a feedstock for producing renewable, high-energy liquid fuels such as diesel. It is important for the United States to develop alternative renewable oil sources because 42% of the current energy market in the United States is for liquid fuels, and 38% of these fuels are imported. In 1979, the US Department of Energy (DOE) and the National Renewable Energy Laboratory (NREL) initiated the Aquatic Species Project as part of the overall effort in biofuels. The project began to focus exclusively on fuels from microalgae in 1982. Estimates show that the technology being developed by the project can provide as much as 7% of the total current energy demand. The program`s basic premise is that microalgae, which have been called the most productive biochemical factories in the world, can produce up to 30 times more oil per unit of growth area than land plants. Selected papers were processed separately for inclusion in the Energy Science and Technology Database.

  13. CLIMATE CHANGE AND AQUATIC INVASIVE SPECIES (Final Report)

    EPA Science Inventory

    This report reviews available literature on climate-change effects on aquatic invasive species (AIS) and examines state-level AIS management activities. Data on management activities came from publicly available information, was analyzed with respect to climate-change effects, a...

  14. Global ecological impacts of invasive species in aquatic ecosystems.

    PubMed

    Gallardo, Belinda; Clavero, Miguel; Sánchez, Marta I; Vilà, Montserrat

    2016-01-01

    The introduction of invasive species, which often differ functionally from the components of the recipient community, generates ecological impacts that propagate along the food web. This review aims to determine how consistent the impacts of aquatic invasions are across taxa and habitats. To that end, we present a global meta-analysis from 151 publications (733 cases), covering a wide range of invaders (primary producers, filter collectors, omnivores and predators), resident aquatic community components (macrophytes, phytoplankton, zooplankton, benthic invertebrates and fish) and habitats (rivers, lakes and estuaries). Our synthesis suggests a strong negative influence of invasive species on the abundance of aquatic communities, particularly macrophytes, zooplankton and fish. In contrast, there was no general evidence for a decrease in species diversity in invaded habitats, suggesting a time lag between rapid abundance changes and local extinctions. Invaded habitats showed increased water turbidity, nitrogen and organic matter concentration, which are related to the capacity of invaders to transform habitats and increase eutrophication. The expansion of invasive macrophytes caused the largest decrease in fish abundance, the filtering activity of filter collectors depleted planktonic communities, omnivores (including both facultative and obligate herbivores) were responsible for the greatest decline in macrophyte abundance, and benthic invertebrates were most negatively affected by the introduction of new predators. These impacts were relatively consistent across habitats and experimental approaches. Based on our results, we propose a framework of positive and negative links between invasive species at four trophic positions and the five different components of recipient communities. This framework incorporates both direct biotic interactions (predation, competition, grazing) and indirect changes to the water physicochemical conditions mediated by invaders (habitat

  15. Global ecological impacts of invasive species in aquatic ecosystems.

    PubMed

    Gallardo, Belinda; Clavero, Miguel; Sánchez, Marta I; Vilà, Montserrat

    2016-01-01

    The introduction of invasive species, which often differ functionally from the components of the recipient community, generates ecological impacts that propagate along the food web. This review aims to determine how consistent the impacts of aquatic invasions are across taxa and habitats. To that end, we present a global meta-analysis from 151 publications (733 cases), covering a wide range of invaders (primary producers, filter collectors, omnivores and predators), resident aquatic community components (macrophytes, phytoplankton, zooplankton, benthic invertebrates and fish) and habitats (rivers, lakes and estuaries). Our synthesis suggests a strong negative influence of invasive species on the abundance of aquatic communities, particularly macrophytes, zooplankton and fish. In contrast, there was no general evidence for a decrease in species diversity in invaded habitats, suggesting a time lag between rapid abundance changes and local extinctions. Invaded habitats showed increased water turbidity, nitrogen and organic matter concentration, which are related to the capacity of invaders to transform habitats and increase eutrophication. The expansion of invasive macrophytes caused the largest decrease in fish abundance, the filtering activity of filter collectors depleted planktonic communities, omnivores (including both facultative and obligate herbivores) were responsible for the greatest decline in macrophyte abundance, and benthic invertebrates were most negatively affected by the introduction of new predators. These impacts were relatively consistent across habitats and experimental approaches. Based on our results, we propose a framework of positive and negative links between invasive species at four trophic positions and the five different components of recipient communities. This framework incorporates both direct biotic interactions (predation, competition, grazing) and indirect changes to the water physicochemical conditions mediated by invaders (habitat

  16. Arsenic and mercury in native aquatic bryophytes: differences among species.

    PubMed

    Díaz, Santiago; Villares, Rubén; López, Jesús; Carballeira, Alejo

    2013-04-01

    This study investigated the capacities of five species of aquatic bryophytes to accumulate As and Hg from their natural habitats in rivers in Galicia (NW Spain). The distributions of the concentrations of both elements in all species were skewed to the right, with a higher incidence of extreme values in the As data, which may indicate a greater degree of contamination by this metalloid. There were no significant differences in the accumulation of either of the elements between the different species studied, which justifies their combined use as biomonitors of As and Hg, at least in the study area.

  17. Species-specific sensitivity of aquatic macrophytes towards two herbicides.

    PubMed

    Cedergreen, Nina; Spliid, Niels Henrik; Streibig, Jens C

    2004-07-01

    The s-triazine herbicide terbutylazine, an inhibitor of photosystem II, is often found in surface waters in concentrations < 1 microg L(-1), but concentrations up to 13 microg L(-1) have been measured. To study the effect on the aquatic flora, we tested the sensitivity of 10 aquatic macrophyte species and a natural epiphyte community in a 2-week laboratory multispecies test at constant terbutylazine concentrations and two irradiance regimes. The data were described by a log-logistic concentration-response model and species sensitivity distributions (SSDs) were created from the EC50 and EC10 values. The 5% hazard concentration (HC5) of the EC10-based SSD for terbutylazine was 1 and 3 microg L(-1); hence the low chronic terbutylazine concentrations measured in the environment are not likely to affect the macrophyte community. To compare the species sensitivity between different groups of herbicides, SSDs were constructed from a published study on the sulfonylurea metsulfuron-methyl, an inhibitor of acetolactate synthase. There was no correlation between species-specific sensitivity to the two herbicides; hence, the combined exposure of different herbicides might affect the macrophyte community more broadly rather than seriously affecting a few susceptible species. Evaluating the standard procedure of leaving at least a factor of 100 between the EC50 of standard tests on Lemna sp. and the predicted environmental concentration seems to be protective for at least 95% of the macrophyte species for both terbutylazine and metsulfuron-methyl. PMID:15223257

  18. Attached bacterial populations shared by four species of aquatic angiosperms.

    PubMed

    Crump, Byron C; Koch, Evamaria W

    2008-10-01

    Symbiotic relationships between microbes and plants are common and well studied in terrestrial ecosystems, but little is known about such relationships in aquatic environments. We compared the phylogenetic diversities of leaf- and root-attached bacteria from four species of aquatic angiosperms using denaturing gradient gel electrophoresis (DGGE) and DNA sequencing of PCR-amplified 16S rRNA genes. Plants were collected from three beds in Chesapeake Bay at sites characterized as freshwater (Vallisneria americana), brackish (Potomogeton perfoliatus and Stuckenia pectinata), and marine (Zostera marina). DGGE analyses showed that bacterial communities were very similar for replicate samples of leaves from canopy-forming plants S. pectinata and P. perfoliatus and less similar for replicate samples of leaves from meadow-forming plants Z. marina and V. americana and of roots of all species. In contrast, bacterial communities differed greatly among plant species and between leaves and roots. DNA sequencing identified 154 bacterial phylotypes, most of which were restricted to single plant species. However, 12 phylotypes were found on more than one plant species, and several of these phylotypes were abundant in clone libraries and represented the darkest bands in DGGE banding patterns. Root-attached phylotypes included relatives of sulfur-oxidizing Gammaproteobacteria and sulfate-reducing Deltaproteobacteria. Leaf-attached phylotypes included relatives of polymer-degrading Bacteroidetes and phototrophic Alphaproteobacteria. Also, leaves and roots of three plant species hosted relatives of methylotrophic Betaproteobacteria belonging to the family Methylophilaceae. These results suggest that aquatic angiosperms host specialized communities of bacteria on their surfaces, including several broadly distributed and potentially mutualistic bacterial populations.

  19. Assessing the effects of climate change on aquatic invasive species.

    PubMed

    Rahel, Frank J; Olden, Julian D

    2008-06-01

    Different components of global environmental change are typically studied and managed independently, although there is a growing recognition that multiple drivers often interact in complex and nonadditive ways. We present a conceptual framework and empirical review of the interactive effects of climate change and invasive species in freshwater ecosystems. Climate change is expected to result in warmer water temperatures, shorter duration of ice cover, altered streamflow patterns, increased salinization, and increased demand for water storage and conveyance structures. These changes will alter the pathways by which non-native species enter aquatic systems by expanding fish-culture facilities and water gardens to new areas and by facilitating the spread of species during floods. Climate change will influence the likelihood of new species becoming established by eliminating cold temperatures or winter hypoxia that currently prevent survival and by increasing the construction of reservoirs that serve as hotspots for invasive species. Climate change will modify the ecological impacts of invasive species by enhancing their competitive and predatory effects on native species and by increasing the virulence of some diseases. As a result of climate change, new prevention and control strategies such as barrier construction or removal efforts may be needed to control invasive species that currently have only moderate effects or that are limited by seasonally unfavorable conditions. Although most researchers focus on how climate change will increase the number and severity of invasions, some invasive coldwater species may be unable to persist under the new climate conditions. Our findings highlight the complex interactions between climate change and invasive species that will influence how aquatic ecosystems and their biota will respond to novel environmental conditions.

  20. [Species sensitive distribution for aquatic biota exposed to triazophos].

    PubMed

    Chen, Bo-Yu; Zheng, Si-Rui; Niu, Xi-Cheng; Zhao, Jin-Song

    2011-04-01

    The increasing pollution of organophosphorus pesticides (OP) in water have been of concerns. Taking the widely used triazophos as the object, a species sensitivity distribution (SSD) model was developed using a log-logistic distribution based on the median effective concentrations (EC50) of triazophos to aquatic species at various trophic levels, and then the model was tested and evaluated using probability plots and good-of-fit tests. The results showed that the SSD for aquatic biota exposed to triazophos was well fitted by a log-logistic distribution, which was totally determined by the two parameters, alpha = -0.4788 and beta = 0.7546, with standard error 0.2381 and 0.1078 respectively. Based on the SSD model, the hazardous concentration for 5% of the species (HC5) and the criteria maximum concentration (CMC) of triazophos were 1.992 x 10(-3) mg/L and 9.96 x 10(-4) mg/L, respectively. Through comparing the HC5 and CMC with the safe concentration for single-species, it could be found that environmental quality criteria derived from the SSD model was more strict, and closed to the real ecological environment. In addition, according to the reported data, the potentially affected fraction (PAF) of species exposed to triazophos in the Laizhou Bay (Bohai Sea, China) area was 0.36% predicted by the SSD model, and the corresponding risk might not be significant. PMID:21717754

  1. Life support for aquatic species - past; present; future

    NASA Astrophysics Data System (ADS)

    Slenzka, K.

    Life Support is a basic issue since manned space flight began. Not only to support astronauts and cosmonauts with the essential things to live, however, also animals which were carried for research to space etc together with men need support systems to survive under space conditions. Most of the animals transported to space participate at the life support system of the spacecraft. However, aquatic species live in water as environment and thus need special developments. Research with aquatic animals has a long tradition in manned space flight resulting in numerous life support systems for them starting with simple plastic bags up to complex support hardware. Most of the recent developments have to be identified as part of a technological oriented system and can be described as small technospheres. As the importance arose to study our Earth as the extraordinary Biosphere we live in, the modeling of small ecosystems began as part of ecophysiological research. In parallel the investigations of Bioregenerative Life Support Systems were launched and identified as necessity for long-term space missions or traveling to Moon and Mars and beyond. This paper focus on previous developments of Life Support Systems for aquatic animals and will show future potential developments towards Bioregenerative Life Support which additionally strongly benefits to our Earth's basic understanding.

  2. Life support for aquatic species--past; present; future.

    PubMed

    Slenzka, K

    2002-01-01

    Life Support is a basic issue since manned space flight began. Not only to support astronauts and cosmonauts with the essential things to live, however, also animals which were carried for research to space etc. together with men need support systems to survive under space conditions. Most of the animals transported to space participate at the life support system of the spacecraft. However, aquatic species live in water as environment and thus need special developments. Research with aquatic animals has a long tradition in manned space flight resulting in numerous life support systems for them starting with simple plastic bags up to complex support hardware. Most of the recent developments have to be identified as part of a technological oriented system and can be described as small technospheres. As the importance arose to study our Earth as the extraordinary Biosphere we live in, the modeling of small ecosystems began as part of ecophysiological research. In parallel the investigations of Bioregenerative Life Support Systems were launched and identified as necessity for long-term space missions or traveling to Moon and Mars and beyond. This paper focus on previous developments of Life Support Systems for aquatic animals and will show future potential developments towards Bioregenerative Life Support which additionally strongly benefits to our Earth's basic understanding.

  3. 75 FR 54648 - Proposed Information Collection; Nonindigenous Aquatic Species Sighting Reporting Form

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-09-08

    ... the distribution of nonindigenous aquatic species, primarily fish, in open waters of the United States... because the USGS cannot be everywhere, observing and monitoring all open waters for nonindigenous aquatic.... Geological Survey. BILLING CODE 4310-AM-P...

  4. 75 FR 53273 - Federal Aquatic Nuisance Species Research Risk Analysis Protocol

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-08-31

    ... controlling aquatic nuisance species, and implementing the Nonindigenous Aquatic Nuisance Prevention and... assessment, risk characterization, risk communication, risk management, and policy relating to risk. This... needed, establishment and implementation of a risk management plan (Part II), with the combined...

  5. Positional strategy of trunk muscles among aquatic, semi-aquatic and terrestrial species in Urodela.

    PubMed

    Omura, Ayano; Anzai, Wataru; Koyabu, Daisuke; Endo, Hideki

    2015-09-01

    Clarification of the trunk structure in Urodela is important in understanding the locomotive evolution of basal tetrapods. The components of the muscular trunk wall among Urodela using different modes of locomotion were compared. Since the whole trunk may be used for swimming and the effect of limbs may be small in the more aquatic species, they showed smaller differences in the trunk muscles among anterior, middle and posterior sections of the trunk. By contrast, in the more terrestrial species, the dorsal and abdominal muscles are larger in the middle section than those in the anterior and posterior sections. High compressive stresses occur in the supporting limbs and their insertion at the trunk on the ventral side, and spread from the forelimbs along the back to the supporting hindlimbs on the dorsal side. Tensile stresses occur in the middle ventral part. The components of the trunk muscles among the three sections may reflect differences in stresses occurring in the trunk of the more terrestrial species. The findings also suggest that in the middle section, larger dorsal muscles for stiffening the back to maintain posture and larger abdominal muscles are responsible for balancing the body weight while it is supported by the limbs in the more terrestrial species. PMID:25843153

  6. Positional strategy of trunk muscles among aquatic, semi-aquatic and terrestrial species in Urodela.

    PubMed

    Omura, Ayano; Anzai, Wataru; Koyabu, Daisuke; Endo, Hideki

    2015-09-01

    Clarification of the trunk structure in Urodela is important in understanding the locomotive evolution of basal tetrapods. The components of the muscular trunk wall among Urodela using different modes of locomotion were compared. Since the whole trunk may be used for swimming and the effect of limbs may be small in the more aquatic species, they showed smaller differences in the trunk muscles among anterior, middle and posterior sections of the trunk. By contrast, in the more terrestrial species, the dorsal and abdominal muscles are larger in the middle section than those in the anterior and posterior sections. High compressive stresses occur in the supporting limbs and their insertion at the trunk on the ventral side, and spread from the forelimbs along the back to the supporting hindlimbs on the dorsal side. Tensile stresses occur in the middle ventral part. The components of the trunk muscles among the three sections may reflect differences in stresses occurring in the trunk of the more terrestrial species. The findings also suggest that in the middle section, larger dorsal muscles for stiffening the back to maintain posture and larger abdominal muscles are responsible for balancing the body weight while it is supported by the limbs in the more terrestrial species.

  7. Incorporating climate science in applications of the US endangered species act for aquatic species.

    PubMed

    McClure, Michelle M; Alexander, Michael; Borggaard, Diane; Boughton, David; Crozier, Lisa; Griffis, Roger; Jorgensen, Jeffrey C; Lindley, Steven T; Nye, Janet; Rowland, Melanie J; Seney, Erin E; Snover, Amy; Toole, Christopher; VAN Houtan, Kyle

    2013-12-01

    Aquatic species are threatened by climate change but have received comparatively less attention than terrestrial species. We gleaned key strategies for scientists and managers seeking to address climate change in aquatic conservation planning from the literature and existing knowledge. We address 3 categories of conservation effort that rely on scientific analysis and have particular application under the U.S. Endangered Species Act (ESA): assessment of overall risk to a species; long-term recovery planning; and evaluation of effects of specific actions or perturbations. Fewer data are available for aquatic species to support these analyses, and climate effects on aquatic systems are poorly characterized. Thus, we recommend scientists conducting analyses supporting ESA decisions develop a conceptual model that links climate, habitat, ecosystem, and species response to changing conditions and use this model to organize analyses and future research. We recommend that current climate conditions are not appropriate for projections used in ESA analyses and that long-term projections of climate-change effects provide temporal context as a species-wide assessment provides spatial context. In these projections, climate change should not be discounted solely because the magnitude of projected change at a particular time is uncertain when directionality of climate change is clear. Identifying likely future habitat at the species scale will indicate key refuges and potential range shifts. However, the risks and benefits associated with errors in modeling future habitat are not equivalent. The ESA offers mechanisms for increasing the overall resilience and resistance of species to climate changes, including establishing recovery goals requiring increased genetic and phenotypic diversity, specifying critical habitat in areas not currently occupied but likely to become important, and using adaptive management. Incorporación de las Ciencias Climáticas en las Aplicaciones del

  8. Incorporating climate science in applications of the US endangered species act for aquatic species.

    PubMed

    McClure, Michelle M; Alexander, Michael; Borggaard, Diane; Boughton, David; Crozier, Lisa; Griffis, Roger; Jorgensen, Jeffrey C; Lindley, Steven T; Nye, Janet; Rowland, Melanie J; Seney, Erin E; Snover, Amy; Toole, Christopher; VAN Houtan, Kyle

    2013-12-01

    Aquatic species are threatened by climate change but have received comparatively less attention than terrestrial species. We gleaned key strategies for scientists and managers seeking to address climate change in aquatic conservation planning from the literature and existing knowledge. We address 3 categories of conservation effort that rely on scientific analysis and have particular application under the U.S. Endangered Species Act (ESA): assessment of overall risk to a species; long-term recovery planning; and evaluation of effects of specific actions or perturbations. Fewer data are available for aquatic species to support these analyses, and climate effects on aquatic systems are poorly characterized. Thus, we recommend scientists conducting analyses supporting ESA decisions develop a conceptual model that links climate, habitat, ecosystem, and species response to changing conditions and use this model to organize analyses and future research. We recommend that current climate conditions are not appropriate for projections used in ESA analyses and that long-term projections of climate-change effects provide temporal context as a species-wide assessment provides spatial context. In these projections, climate change should not be discounted solely because the magnitude of projected change at a particular time is uncertain when directionality of climate change is clear. Identifying likely future habitat at the species scale will indicate key refuges and potential range shifts. However, the risks and benefits associated with errors in modeling future habitat are not equivalent. The ESA offers mechanisms for increasing the overall resilience and resistance of species to climate changes, including establishing recovery goals requiring increased genetic and phenotypic diversity, specifying critical habitat in areas not currently occupied but likely to become important, and using adaptive management. Incorporación de las Ciencias Climáticas en las Aplicaciones del

  9. 78 FR 29378 - Aquatic Nuisance Species Task Force; Public Teleconference/Webinar

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-05-20

    ... Guidelines, National Invasive Species Awareness Week, Michigan and Mississippi ANS Management Plans, and... Fish and Wildlife Service Aquatic Nuisance Species Task Force; Public Teleconference/ Webinar AGENCY..., announce a public teleconference/webinar of the Aquatic Nuisance Species Task Force (ANS Task Force)....

  10. Emergent aquatics: stand establishment, management, and species screening

    SciTech Connect

    Pratt, D.C.; Andrews, N.J.; Dubbe, D.R.; Garver, E.G.; Penko, M.; Read, P.E.; Zimmerman, E.S.

    1982-11-01

    Several emergent aquatic species have been identified as potential biomass crops, including Typha spp. (cattail), Scirpus spp. (rush), Sparganium spp. (bur reed), and Phragmites (reed). This report discusses first year results from studies of stand establishment and management, Typha nutrient requirements, wetland species yield comparisons, and Typha micropropagation. In a comparison of the relative effectiveness of seed, seedlings, and rhizomes for stand establishment, rhizomes appeared to be more consistent and productive under a wire variety of conditions. Both rhizomes and seedling established plots grew successfully on excavated peatland sites. First season results from a multiyear fertilizer rate experiment indicate that fertilizer treatment resulted in significantly increased tissue nutrient concentrations which should carry over into subsequent growing seasons. Shoot density and belowground dry weight were also significantly increased by phosphorus + potassium and potassium applications, respectively. First season yields of selected wetland species from managed paddies generally were comparable to yields reported from natural stands. Several particularly productive clones of Typha spp. have been identified. A method of establishing Typha in tissue culture is described.

  11. Land-use proxies for aquatic species invasions in the Laurentian Great Lakes

    EPA Science Inventory

    Aquatic invasive species adversely impact ecosystems, human health, and the economy of the Laurentian Great Lakes region. Targeted preventative and eradication efforts in response to early detection of invasive species can be both cost advantageous and effective. But where should...

  12. Development and Practical Application of Petroleum and Dispersant Interspecies Correlation Models for Aquatic Species

    EPA Science Inventory

    Assessing the acute toxicity of physically and chemically dispersed oil following an oil spill has generally relied on existing toxicological data for a relatively limited number of aquatic species. Recognition of differences in species sensitivities to contaminants has facilitat...

  13. Biodiesel/Aquatic Species Project report, FY 1992

    SciTech Connect

    Brown, L.; Jarvis, E.; Dunahay, T.; Roessler, P.; Zeiler, K. ); Sprague, S. )

    1993-05-01

    The primary goal of the Biodiesel/Aquatic Species Project is to develop the technology for growing microalgae as a renewable biomass feedstock for the production of a diesel fuel substitute (biodiesel), thereby reducing the need for imported petroleum. Microalgae are of interest as a feedstock because of their high growth rates and tolerance to varying environmental conditions, and because the oils (lipids) they produce can be extracted and converted to substitute petroleum fuels such as biodiesel. Microalgae can be grown in arid and semi-arid regions with poor soil quality, and saline water from aquifers or the ocean can be used for growing microalgae. Biodiesel is an extremely attractive candidate to fulfill the need for a diesel fuel substitute. Biodiesel is a cleaner fuel than petroleum diesel; it is virtually free of sulfur, and emissions of hydrocarbons, carbon monoxide, and particulates during combustion are significantly reduced in comparison to emissions from petroleum diesel. Biodiesel provides essentially the same energy content and power output as petroleum-based diesel fuel.

  14. Angler awareness of aquatic nuisance species and potential transport mechanisms

    USGS Publications Warehouse

    Gates, K.K.; Guy, C.S.; Zale, A.V.; Horton, T.B.

    2009-01-01

    The role anglers play in transporting aquatic nuisance species (ANS) is important in managing infestations and preventing introductions. The objectives of this study were to: (1) quantify angler movement patterns in southwestern Montana, ANS awareness and equipment cleaning practices; and (2) quantify the amount of soil transported on boots and waders. Mean distance travelled by residents from their home to the survey site was 115 km (??17, 95% CI). Mean distance travelled by non-residents was 1738 km (??74). Fifty-one percent of residents and 49% of non-residents reported occasionally, rarely or never cleaning their boots and waders between uses. Mean weight of soil carried on one boot leg was 8.39 g (??1.50). Movement and equipment cleaning practices of anglers in southwestern Montana suggest that future control of ANS dispersal may require restricting the use of felt-soled wading boots, requiring river-specific wading equipment or providing cleaning stations and requiring their use. ?? 2009 Blackwell Publishing Ltd.

  15. Two new Tetramitus species (Heterolobosea, Vahlkampfiidae) from cold aquatic environments.

    PubMed

    Robinson, Bret S; De Jonckheere, Johan F; Dobson, Philip J

    2007-01-01

    Characterisation of the protists of cold environments provides important background for assessing the effects of climate change on microbial communities. Tetramitus angularis n. sp., from aquatic environments in Iceland and Switzerland, is the first vahlkampfiid recognised to have a characteristic Tetramitus flagellate stage combined with pre-formed excystment pores, which are not typical of this genus. T. angularis amoebae have a typical vahlkampfiid locomotive form and contain prominent lipid inclusions. Flagellates have a collar and cytostome, and can be mono- to multi-nucleate with corresponding change in cell shape from cylindrical to ellipsoidal and variable number of flagella. Cysts are round to semi-angular and have 2-5 pores closed by protruding, translucent plugs. A second organism, T. parangularis n. sp. from Alaska, has similar cysts but a flagellate stage has not been recognised; ITS sequence divergence is consistent with species criteria in the Vahlkampfiidae. Phylogenetic analysis of sequence data for the 5.8S rDNA region clusters the new spp. with T. rostratus, T. entericus and T. waccamawensis.

  16. Biodiesel from aquatic species. Project report: FY 1993

    SciTech Connect

    Brown, L.M.; Sprague, S.; Jarvis, E.E.; Dunahay, T.G.; Roessler, P.G.; Zeiler, K.G.

    1994-01-01

    Researchers in the Biodiesel/Aquatic Species Project focus on the use of microalgae as a feedstock for producing renewable, high-energy liquid fuels. The program`s basic premise is that microalgae, which have been called the most productive biochemical factories in the world, can produce up to 30 times more oil per unit of growth area than land plants. It is estimated that 150 to 400 barrels of oil per acre per year (0.06 to 0.16 million liters/hectar) could be produced with microalgal oil technology. Initial commercialization of this technology is envisioned for the desert Southwest because this area provides high solar radiation and offers flat land that has few competing uses (hence low land costs). Similarly, there are large saline aquifers with few competing uses in the region. This water source could provide a suitable, low-cost medium for the growth of many microalgae. The primary area of research during FY 1993 was the effort to genetically improve microalgae in order to control the timing and magnitude of lipid accumulation. Increased lipid content will have a direct effect on fuel price, and the control of lipid content is a major project goal. The paper describes progress on the following: culture collection; molecular biology of lipid biosynthesis; microalgal transformation; and environmental, safety, and health and quality assurance.

  17. Influence of Taxonomic Relatedness and Chemical Mode of Action in Acute Interspecies Estimation Models for Aquatic species

    EPA Science Inventory

    Ecological risks to aquatic organisms are typically assessed using toxicity data for relatively few species and with limited understanding of relative species sensitivity. We developed a comprehensive set of interspecies correlation estimation (ICE) models for aquatic organisms a...

  18. Efficient distinction of invasive aquatic plant species from non-invasive related species using DNA barcoding.

    PubMed

    Ghahramanzadeh, R; Esselink, G; Kodde, L P; Duistermaat, H; van Valkenburg, J L C H; Marashi, S H; Smulders, M J M; van de Wiel, C C M

    2013-01-01

    Biological invasions are regarded as threats to global biodiversity. Among invasive aliens, a number of plant species belonging to the genera Myriophyllum, Ludwigia and Cabomba, and to the Hydrocharitaceae family pose a particular ecological threat to water bodies. Therefore, one would try to prevent them from entering a country. However, many related species are commercially traded, and distinguishing invasive from non-invasive species based on morphology alone is often difficult for plants in a vegetative stage. In this regard, DNA barcoding could become a good alternative. In this study, 242 samples belonging to 26 species from 10 genera of aquatic plants were assessed using the chloroplast loci trnH-psbA, matK and rbcL. Despite testing a large number of primer sets and several PCR protocols, the matK locus could not be amplified or sequenced reliably and therefore was left out of the analysis. Using the other two loci, eight invasive species could be distinguished from their respective related species, a ninth one failed to produce sequences of sufficient quality. Based on the criteria of universal application, high sequence divergence and level of species discrimination, the trnH-psbA noncoding spacer was the best performing barcode in the aquatic plant species studied. Thus, DNA barcoding may be helpful with enforcing a ban on trade of such invasive species, such as is already in place in the Netherlands. This will become even more so once DNA barcoding would be turned into machinery routinely operable by a nonspecialist in botany and molecular genetics.

  19. Ohio Aquatic Gap Analysis-An Assessment of the Biodiversity and Conservation Status of Native Aquatic Animal Species

    USGS Publications Warehouse

    Covert, S. Alex; Kula, Stephanie P.; Simonson, Laura A.

    2007-01-01

    The goal of the GAP Analysis Program is to keep common species common by identifying those species and habitats that are not yet adequately represented in the existing matrix of conservation lands. The Gap Analysis Program (GAP) is sponsored by the Biological Resources Discipline of the U.S. Geological Survey (USGS). The Ohio Aquatic GAP (OH-GAP) is a pilot project that is applying the GAP concept to aquatic-specifically, riverine-data. The mission of GAP is to provide regional assessments of the conservation status of native animal species and to facilitate the application of this information to land-management activities. OH-GAP accomplished this through * mapping aquatic habitat types, * mapping the predicted distributions of fish, crayfish, and bivalves, * documenting the presence of aquatic species in areas managed for conservation, * providing GAP results to the public, planners, managers, policy makers, and researchers, and * building cooperation with multiple organizations to apply GAP results to state and regional management activities. Gap analysis is a coarse-scale assessment of aquatic biodiversity and conservation; the goal is to identify gaps in the conservation of native aquatic species. It is not a substitute for biological field studies and monitoring programs. Gap analysis was conducted for the continuously flowing streams in Ohio. Lakes, reservoirs, wetlands, and the Lake Erie islands were not included in this analysis. The streams in Ohio are in the Lake Erie and Ohio River watersheds and pass through six of the level III ecoregions defined by Omernik: the Eastern Corn Belt Plains, Southern Michigan/Northern Indiana Drift Plains, Huron/Erie Lake Plain, Erie Drift Plains, Interior Plateau, and the Western Allegheny Plateau. To characterize the aquatic habitats available to Ohio fish, crayfish, and bivalves, a classification system needed to be developed and mapped. The process of classification includes delineation of areas of relative

  20. The U.S. Geological Survey’s nonindigenous aquatic species database: over thirty years of tracking introduced aquatic species in the United States (and counting)

    USGS Publications Warehouse

    Fuller, Pam L.; Neilson, Matthew E.

    2015-01-01

    The U.S. Geological Survey’s Nonindigenous Aquatic Species (NAS) Database has tracked introductions of freshwater aquatic organisms in the United States for the past four decades. A website provides access to occurrence reports, distribution maps, and fact sheets for more than 1,000 species. The site also includes an on-line reporting system and an alert system for new occurrences. We provide an historical overview of the database, a description of its current capabilities and functionality, and a basic characterization of the data contained within the database.

  1. INTER-SPECIES MODELS FOR ACUTE AQUATIC TOXICITY BASED ON MECHANISM OF ACTION

    EPA Science Inventory

    This presentation will provide interspecies QSARs for acute toxicity to 17 aquatic species, such as fish, snail, tadpole, hydrozoan, crustacean, insect larvae, and bacteria developed using 5,000 toxic effect results for approximately 2400 chemicals.

  2. Application of environmental DNA for inventory and monitoring of aquatic species

    USGS Publications Warehouse

    Pilliod, David S.; Goldberg, Caren S.; Laramie, Matthew B.; Waits, Lisette P.

    2013-01-01

    This fact sheet was created to help biologists and resource managers understand emerging methods for detecting environmental DNA and their potential application for inventorying and monitoring aquatic species. It is a synthesis of published information.

  3. Toxicity of the cyanobacterial neurotoxin beta-N-methylamino-L-alanine to three aquatic animal species.

    PubMed

    Purdie, Esme L; Metcalf, James S; Kashmiri, Shereen; Codd, Geoffrey A

    2009-01-01

    Beta-N-methylamino-L-alanine (BMAA), a neurotoxin and candidate contributory cause of neurodegenerative diseases including amyotrophic lateral sclerosis, is produced by aquatic and terrestrial cyanobacteria. We have determined BMAA toxicity to three aquatic animal species: zebra fish (Danio rerio), brine shrimp (Artemia salina) and the protozoan Nassula sorex. Responses included: clonus convulsions and abnormal spinal axis formation (D. rerio), loss of phototaxis (A. salina) and mortalities (all species). These systems offer potential to further understand BMAA toxicity and the bioaccumulation and fates of BMAA in aquatic food chains leading to potential human exposure.

  4. Augmenting aquatic species sensitivity distributions with interspecies toxicity estimation models

    EPA Science Inventory

    Species sensitivity distributions (SSD) are cumulative distribution functions of species toxicity values. The SSD approach is increasingly being used in ecological risk assessment, but is often limited by available toxicity data necessary for diverse species representation. In ...

  5. 78 FR 14351 - Invasive Species Advisory Committee; Meeting Cancellation

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-03-05

    ... Office of the Secretary Invasive Species Advisory Committee; Meeting Cancellation AGENCY: Office of the Secretary, Interior. ACTION: Notice of meeting cancellation. SUMMARY: The meeting of the Invasive Species....gov . SUPPLEMENTARY INFORMATION: The ISAC is comprised of 31 nonfederal invasive species experts...

  6. Warming-induced reductions in body size are greater in aquatic than terrestrial species

    PubMed Central

    Forster, Jack; Hirst, Andrew G.; Atkinson, David

    2012-01-01

    Most ectothermic organisms mature at smaller body sizes when reared in warmer conditions. This phenotypically plastic response, known as the “temperature-size rule” (TSR), is one of the most taxonomically widespread patterns in biology. However, the TSR remains a longstanding life-history puzzle for which no dominant driver has been found. We propose that oxygen supply plays a central role in explaining the magnitude of ectothermic temperature-size responses. Given the much lower oxygen availability and greater effort required to increase uptake in water vs. air, we predict that the TSR in aquatic organisms, especially larger species with lower surface area–body mass ratios, will be stronger than in terrestrial organisms. We performed a meta-analysis of 1,890 body mass responses to temperature in controlled experiments on 169 terrestrial, freshwater, and marine species. This reveals that the strength of the temperature-size response is greater in aquatic than terrestrial species. In animal species of ∼100 mg dry mass, the temperature-size response of aquatic organisms is 10 times greater than in terrestrial organisms (−5.0% °C−1 vs. −0.5% °C−1). Moreover, although the size response of small (<0.1 mg dry mass) aquatic and terrestrial species is similar, increases in species size cause the response to become increasingly negative in aquatic species, as predicted, but on average less negative in terrestrial species. These results support oxygen as a major driver of temperature-size responses in aquatic organisms. Further, the environment-dependent differences parallel latitudinal body size clines, and will influence predicted impacts of climate warming on food production, community structure, and food-web dynamics. PMID:23129645

  7. 77 FR 46730 - Aquatic Nuisance Species Task Force Strategic Plan 2013-2017

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-08-06

    ... Strategic Plan 2013-2017 AGENCY: National Marine Fisheries Service (NMFS), National Oceanic and Atmospheric Administration (NOAA), Commerce. ACTION: Notice of availability of Strategic Plan; request for comments. SUMMARY... Nuisance Species Task Force Strategic Plan 2013--2017 (Plan), approved by the Aquatic Nuisance Species...

  8. Effort and Potential Efficiencies for Aquatic Non-native Species Early Detection

    EPA Science Inventory

    This manuscript is based on the early aquatic non-native species detection research in the Duluth-Superior harbor. The problem of early detection is essentially that of a "needle in a haystack" - to detect a newly arrived and presumably rare non-native species with a high probabi...

  9. Status and trends of Ontario's Sydenham River ecosystem in relation to aquatic species at risk.

    PubMed

    Staton, Shawn K; Dextrase, A; Metcalfe-Smith, J L; Di Maio, J; Nelson, M; Parish, J; Kilgour, B; Holm, E

    2003-01-01

    The Sydenham River in southwestern Ontario is located in the Mixedwood Plains Ecozone, which supports the greatest diversity of flora and fauna in Canada. The river historically supported a rich aquatic community that included 80 fishes and 34 species of freshwater mussels. Fourteen aquatic species native to the river (8 fishes, 5 mussels and 1 turtle) have been designated as endangered, threatened, or of special concern by the Committee on the Status of Species at Risk in Canada (COSEWIC). A multi-agency Recovery Team was formed in 1999 to ensure the continued survival of these and other rare species in the river. The Sydenham River Recovery Team is the first in Canada to adopt an ecosystem approach to recovery planning for aquatic species. Information on land use patterns, water quality trends, the physical condition of the river, and the distributions of aquatic species at risk was synthesized to gain an understanding of the overall health of the river and its major anthropogenic stresses. Seven of the species at risk have declined in distribution or abundance, and three may be extirpated. The main threat to fishes and mussels is heavy loadings of sediment, nutrients, and possibly pesticides to the river via tile drainage and overland runoff from agricultural lands. A strategy that incorporates four overall approaches (management, stewardship, research and monitoring, and awareness and outreach) was developed to recover and protect this globally significant freshwater ecosystem. PMID:14570419

  10. Preventing, controlling, and managing alien species introduction for the health of aquatic and marine ecosystems

    USGS Publications Warehouse

    Short, C.I.; Gross, S.K.; Wilkinson, D.

    2004-01-01

    The introduction and spread of invasive species is an emerging global problem. As economic and ecological impacts continue to grow, there will be an increasing need to develop innovative solutions and global partnerships to combat the increasing rate of invasions and their accompanying impacts. Threats to sustainable fisheries in North America associated with alien species come from many global directions and sources and can be deliberate or the unintended consequence of other actions. Decisions about the role of sustainable fisheries in protecting and restoring the health of aquatic ecosystems become even more complex when economic and social factors are considered along with environmental impacts, because many intentionally introduced species also have associated economic and community costs and benefits. Actions designed to prevent or control alien species in an aquatic ecosystem are often complicated by these nonenvironmental factors as well as public perception and opinion. Aquatic ecosystems are disturbed to varying degrees by alien species, including disease organisms. Prevention is the first and best line of defense. Determining likely pathways and effective countermeasures is more cost-effective than either eradication or control. Our ability to quickly identify new species and their associated risk to ecosystems is critical in designing and implementing effective control and management actions. Lack of infrastructure and necessary resources, clear-cut authority for regulation and action, and scientific information about the biology of alien species and effective control techniques are often limiting factors that prevent the needed action to protect aquatic ecosystems.

  11. Geographical range, heat tolerance and invasion success in aquatic species

    PubMed Central

    Bates, Amanda E.; McKelvie, Catherine M.; Sorte, Cascade J. B.; Morley, Simon A.; Jones, Nicholas A. R.; Mondon, Julie A.; Bird, Tomas J.; Quinn, Gerry

    2013-01-01

    Species with broader geographical ranges are expected to be ecological generalists, while species with higher heat tolerances may be relatively competitive at more extreme and increasing temperatures. Thus, both traits are expected to relate to increased survival during transport to new regions of the globe, and once there, establishment and spread. Here, we explore these expectations using datasets of latitudinal range breadth and heat tolerance in freshwater and marine invertebrates and fishes. After accounting for the latitude and hemisphere of each species’ native range, we find that species introduced to freshwater systems have broader geographical ranges in comparison to native species. Moreover, introduced species are more heat tolerant than related native species collected from the same habitats. We further test for differences in range breadth and heat tolerance in relation to invasion success by comparing species that have established geographically restricted versus extensive introduced distributions. We find that geographical range size is positively related to invasion success in freshwater species only. However, heat tolerance is implicated as a trait correlated to widespread occurrence of introduced populations in both freshwater and marine systems. Our results emphasize the importance of formal risk assessments before moving heat tolerant species to novel locations. PMID:24266040

  12. Assessment of in silico methods to estimate aquatic species sensitivity

    EPA Science Inventory

    Determining the sensitivity of a diversity of species to environmental contaminants continues to be a significant challenge in ecological risk assessment because toxicity data are generally limited to a few standard species. In many cases, QSAR models are used to estimate toxici...

  13. Conservation planning for imperiled aquatic species in an urbanizing environment

    USGS Publications Warehouse

    Wenger, Seth J.; Freeman, Mary C.; Fowler, Laurie A.; Freeman, Byron J.; Peterson, James T.

    2010-01-01

    As the global area devoted to urban uses grows, an increasing number of freshwater species will face imperilment due to urbanization effects. Management of these impacts on both private and public lands is necessary to ensure species persistence. Such management entails several hallenges: (1) development of a management policy appropriate to the stressors; (2) linking stressor levels to species population attributes; (3) forecasting the effects of alternative management policy decisions on the species, and (4) using adaptive management to adjust the policy in the future. We illustrate how these challenges were addressed under the Etowah Habitat Conservation Plan (Etowah HCP), a management plan for three federally protected fish species in Georgia, USA. The plan involved the creation of a management policy to address the impacts of the greatest stressor, stormwater runoff, as well as other stressors. Models were constructed to link population indices of the three species with a key indicator of stormwater runoff, effective impervious area (EIA). Then, models were applied to projected levels of EIA under full watershed buildout to fine-tune the parameters of the management policy. Forecasting indicated that the most sensitive species, the Etowah darter, was likely to decline by 84% in the absence of the Etowah HCP, but only 23% if the Etowah HCP were implemented. Although there was substantial uncertainty in model predictions, an adaptive management plan was established to incorporate new data and to adjust management policies as necessary.

  14. Comprehensive review on phytotechnology: Heavy metals removal by diverse aquatic plants species from wastewater.

    PubMed

    Rezania, Shahabaldin; Taib, Shazwin Mat; Md Din, Mohd Fadhil; Dahalan, Farrah Aini; Kamyab, Hesam

    2016-11-15

    Environmental pollution specifically water pollution is alarming both in the developed and developing countries. Heavy metal contamination of water resources is a critical issue which adversely affects humans, plants and animals. Phytoremediation is a cost-effective remediation technology which able to treat heavy metal polluted sites. This environmental friendly method has been successfully implemented in constructed wetland (CWs) which is able to restore the aquatic biosystem naturally. Nowadays, many aquatic plant species are being investigated to determine their potential and effectiveness for phytoremediation application, especially high growth rate plants i.e. macrophytes. Based on the findings, phytofiltration (rhizofiltration) is the sole method which defined as heavy metals removal from water by aquatic plants. Due to specific morphology and higher growth rate, free-floating plants were more efficient to uptake heavy metals in comparison with submerged and emergent plants. In this review, the potential of wide range of aquatic plant species with main focus on four well known species (hyper-accumulators): Pistia stratiotes, Eicchornia spp., Lemna spp. and Salvinia spp. was investigated. Moreover, we discussed about the history, methods and future prospects in phytoremediation of heavy metals by aquatic plants comprehensively.

  15. Comprehensive review on phytotechnology: Heavy metals removal by diverse aquatic plants species from wastewater.

    PubMed

    Rezania, Shahabaldin; Taib, Shazwin Mat; Md Din, Mohd Fadhil; Dahalan, Farrah Aini; Kamyab, Hesam

    2016-11-15

    Environmental pollution specifically water pollution is alarming both in the developed and developing countries. Heavy metal contamination of water resources is a critical issue which adversely affects humans, plants and animals. Phytoremediation is a cost-effective remediation technology which able to treat heavy metal polluted sites. This environmental friendly method has been successfully implemented in constructed wetland (CWs) which is able to restore the aquatic biosystem naturally. Nowadays, many aquatic plant species are being investigated to determine their potential and effectiveness for phytoremediation application, especially high growth rate plants i.e. macrophytes. Based on the findings, phytofiltration (rhizofiltration) is the sole method which defined as heavy metals removal from water by aquatic plants. Due to specific morphology and higher growth rate, free-floating plants were more efficient to uptake heavy metals in comparison with submerged and emergent plants. In this review, the potential of wide range of aquatic plant species with main focus on four well known species (hyper-accumulators): Pistia stratiotes, Eicchornia spp., Lemna spp. and Salvinia spp. was investigated. Moreover, we discussed about the history, methods and future prospects in phytoremediation of heavy metals by aquatic plants comprehensively. PMID:27474848

  16. Temporal changes in species interactions in simple aquatic bacterial communities

    PubMed Central

    2012-01-01

    Background Organisms modify their environment and in doing so change the quantity and possibly the quality of available resources. Due to the two-way relationship between organisms and their resource environment, and the complexity it brings to biological communities, measuring species interactions reliably in any biological system is a challenging task. As the resource environment changes, the intensity and even the sign of interactions may vary in time. We used Serratia marcescens and Novosphingobium capsulatum bacteria to study how the interaction between resource environment and organisms influence the growth of the bacterial species during circa 200 generations. We used a sterile-filtering method to measure how changes in resource environment are reflected in growth rates of the two species. Results Changes in the resource environment caused complex time and species composition-dependent effects on bacterial growth performance. Variation in the quality of the growth medium indicated existence of temporally fluctuating within-species facilitation and inhibition, and between-species asymmetric facilitation. Conclusions The interactions between the community members could not be fully predicted based only on the knowledge of the growth performance of each member in isolation. Growth dynamics in sterile-filtered samples of the conditioned growth medium can reveal both biologically meaningful changes in resource availability and temporally changing facilitative resource-mediated interactions between study species. This is the first study we are aware of where the filter-sterilization – growth assay method is applied to study the effect of long-term changes in the environment on species interactions. PMID:22984961

  17. Elucidating differences in metal absorption efficiencies between terrestrial soft-bodied and aquatic species.

    PubMed

    Owsianiak, Mikołaj; Veltman, Karin; Hauschild, Michael Z; Hendriks, A Jan; Steinmann, Zoran J N; Huijbregts, Mark A J

    2014-10-01

    It is unknown whether metal absorption efficiencies in terrestrial soft-bodied species can be predicted with the same metal properties as for aquatic species. Here, we developed models for metal absorption efficiency from the dissolved phase for terrestrial worms and several aquatic species, based on 23 metal physicochemical properties. For the worms, the absorption efficiency was successfully related to 7 properties, and is best predicted with the ionic potential. Different properties (8 in total) were found to be statistically significant in regressions predicting metal absorption in aquatic species, with the covalent index being the best predictor. It is hypothesized that metal absorption by soft-bodied species in soil systems is influenced by the rate of metal supply to the membrane, while in aquatic systems accumulation is solely determined by metal affinity to membrane bound transport proteins. Our results imply that developing predictive terrestrial bioaccumulation and toxicity models for metals must consider metal interactions with soil solids. This may include desorption of a cation bound to soil solids through ion exchange, or metal release from soil surfaces involving breaking of metal-oxygen bonds.

  18. 78 FR 9724 - Invasive Species Advisory Committee; Meetings

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-02-11

    ... is to provide national leadership regarding invasive species issues. Purpose of Meeting: The meeting... Ken Salazar on January 22, 2013. Note: There will be no committee business conducted during...

  19. Sampling design for early detection of aquatic invasive species in Great Lakes ports

    EPA Science Inventory

    We evaluated a pilot adaptive monitoring program for aquatic invasive species (AIS) early detection in Lake Superior. The monitoring program is designed to detect newly-introduced fishes, and encompasses the lake’s three major ports (Duluth-Superior, Sault Ste. Marie, Thund...

  20. Early Detection Monitoring Approaches for Exotic Aquatic Species in Great Lakes Harbors and Embayments

    EPA Science Inventory

    Aquatic invasive species pose a significant ecological and economic threat in the Great Lakes basin. Early detection of invaders is desirable so as to allow for a timely management response, raising the question of how to accomplish this detection in a consistent, cost-effective...

  1. Detection and identification of Malassezia species in domestic animals and aquatic birds by PCR-RFLP

    PubMed Central

    Zia, M.; Mirhendi, H.; Toghyani, M.

    2015-01-01

    The present study aimed at detection and species-level identification of the Malassezia yeasts in domestic animals and aquatic birds by polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP). Samples were collected using tape strips and swabs from 471 animals including 97 horses, 102 cattle, 105 sheep, 20 camels, 60 dogs, 30 cats, 1 hamster, 1 squirrel, 50 aquatic birds and 5 turkeys. Tape-strip samples were examined by direct microscopy. All samples were inoculated on modified Leeming and Notman agar medium. DNA extracted from the yeast colonies was amplified by PCR using primers specific for 26S rDNA. RFLP of the PCR products was performed using Hin6I enzyme, and PCR and RFLP products were visualized by agarose gel electrophoresis. Malassezia yeasts were detected at the following frequencies: 15.46% in horses, 12.74% in cattle, 12.38% in sheep, 28.33% in dogs, 26.66% in cats and 26% in aquatic birds. Eighty colonies of 6 species were isolated: Malassezia globosa 41.25%, Malassezia furfur 22.5%, Malassezia restricta 15%, Malassezia sympodialis 15%, Malassezia pachydermatis 5% and Malassezia slooffiae 1.25%. Therefore different lipophilic Malassezia species are found in a wide diversity of animals and aquatic birds. PCR-RFLP is a suitable technique for identification of different Malassezia species. PMID:27175148

  2. Sampling design for aquatic invasive species early detection in Great Lakes ports

    EPA Science Inventory

    From 2006-2012, we evaluated a pilot aquatic invasive species (AIS) early detection monitoring program in Lake Superior that was designed to detect newly introduced fishes. We established survey protocols for three major ports (Duluth-Superior, Sault Ste. Marie, Thunder Bay) and ...

  3. 75 FR 7622 - Proposed Information Collection; Nonindigenous Aquatic Species Sighting Reporting Form

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-02-22

    ... from the public regarding the distribution of nonindigenous aquatic species, primarily fish, in open... Program because the USGS cannot possibly be everywhere, observing and monitoring all open waters for... Biology, U.S. Geological Survey. BILLING CODE 4311-AM-P...

  4. 77 FR 58097 - Aquatic Nuisance Species Task Force Strategic Plan 2013-2017

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-09-19

    ... From the Federal Register Online via the Government Publishing Office DEPARTMENT OF COMMERCE National Oceanic and Atmospheric Administration RIN 0648-XC120 Aquatic Nuisance Species Task Force Strategic Plan 2013--2017 Correction In notice document 2012-19161, appearing on pages 46730-46732 in...

  5. Status of Aquatic Non-indigenous Species in the St. Louis River System

    EPA Science Inventory

    As part of a study to develop recommendations for aquatic non-indigenous species (NIS) monitoring in Great Lakes areas at risk of invasion, we conducted comprehensive, multi-gear sampling in the lower St. Louis River in 2005-2007. This effort represents the most spatially and ta...

  6. Status of Aquatic Non-indigenous Species in the Duluth-Superior Harbor

    EPA Science Inventory

    As part of a study to develop recommendations for aquatic non-indigenous species (NIS) monitoring in Great Lakes areas at risk of invasion, we conducted comprehensive, multi-gear sampling in the Duluth, MN-Superior, WI harbor and lower St. Louis River in 2005-2007. This effort r...

  7. Early detection monitoring of aquatic invasive species: Measuring performance success in a Lake Superior pilot network

    EPA Science Inventory

    The Great Lakes Water Quality Agreement, Annex 6 calls for a U.S.-Canada, basin-wide aquatic invasive species early detection network by 2015. The objective of our research is to explore survey design strategies that can improve detection efficiency, and to develop performance me...

  8. Founding population size of an aquatic invasive species

    USGS Publications Warehouse

    Kalinowski, Steven T.; Muhlfeld, Clint C.; Guy, Christopher S.; Benjamin Cox,

    2010-01-01

    Non-native species of fish threaten native fishes throughout North America, and in the Rocky Mountains, introduced populations of lake trout threaten native populations of bull trout. Effective management of lake trout and other exotic species require understanding the dynamics of invasion in order to either suppress non-native populations or to prevent their spread. In this study, we used microsatellite genetic data to estimate the number of lake trout that invaded a population of bull trout in Swan Lake, MT. Examination of genetic diversity and allele frequencies within the Swan Lake populations showed that most of the genes in the lake trout population are descended from two founders. This emphasizes the importance of preventing even a few lake trout from colonizing new territory.

  9. Microbial Characteristics of Native Aquatic Species of Savannah River Wetlands

    SciTech Connect

    McKinsey, P.C.

    2000-12-12

    In 1974 the Savannah River Site (SRS) was established as a National Environmental Research Park (NERP) in the United States. NERP provided locations for long-term ecological research investigation. Many of the ecological studies that have been conducted in the past mainly focused on the macroscopic view. The Savannah River Site contains wetlands that are home to many diverse organisms. We conducted a preliminary survey of microbial habitats in order to explore the biodiversity of species-specific symbionts. Bacterial surveys included viable counts, direct counts, isolation, identification, and metabolic profiles.

  10. Aquatic Hyphomycete Species Are Screened by the Hyporheic Zone of Woodland Streams

    PubMed Central

    Chauvet, Eric; Mermillod-Blondin, Florian; Assemat, Fiona; Elger, Arnaud

    2014-01-01

    Aquatic hyphomycetes strongly contribute to organic matter dynamics in streams, but their abilities to colonize leaf litter buried in streambed sediments remain unexplored. Here, we conducted field and laboratory experiments (slow-filtration columns and stream-simulating microcosms) to test the following hypotheses: (i) that the hyporheic habitat acting as a physical sieve for spores filters out unsuccessful strategists from a potential species pool, (ii) that decreased pore size in sediments reduces species dispersal efficiency in the interstitial water, and (iii) that the physicochemical conditions prevailing in the hyporheic habitat will influence fungal community structure. Our field study showed that spore abundance and species diversity were consistently reduced in the interstitial water compared with surface water within three differing streams. Significant differences occurred among aquatic hyphomycetes, with dispersal efficiency of filiform-spore species being much higher than those with compact or branched/tetraradiate spores. This pattern was remarkably consistent with those found in laboratory experiments that tested the influence of sediment pore size on spore dispersal in microcosms. Furthermore, leaves inoculated in a stream and incubated in slow-filtration columns exhibited a fungal assemblage dominated by only two species, while five species were codominant on leaves from the stream-simulating microcosms. Results of this study highlight that the hyporheic zone exerts two types of selection pressure on the aquatic hyphomycete community, a physiological stress and a physical screening of the benthic spore pool, both leading to drastic changes in the structure of fungal community. PMID:24441154

  11. Aquatic biofilms and their responses to disinfection and invading species

    NASA Technical Reports Server (NTRS)

    Smithers, G. A.; Rodgers, E. B.; Obenhuber, D. C.; Huff, T. L.

    1992-01-01

    The control of microbial contamination is a primary concern in the development of a water reclamation system for long-duration manned space flights. This paper describes bench-scale experiments, using both static and recycling water systems, investigating the interaction of bacterial species in the development of a biofilm and their response to the introduction of a disinfectant or of additional species. The results showed that iodine concentrations as high as 15 to 20 mg/l I2 are necessary to completely disinfect a stable biofilm. When S. aueus and E. coli were introduced into a system containing natural mixed culture biofilms, their colonization in the biofilms increased their survival time, from 3 to 5 days as unattached cells to over 60 days when protected in the biofilms. While iodine concentrations of 0.5 to 1 mg/l were enough to eliminate these organisms from the bulk water, concentrations higher than 4.0 mg/l were necessary to completely eliminate these organisms from the biofilm.

  12. Aquatic pollution-induced immunotoxicity in wildlife species.

    PubMed

    Luebke, R W; Hodson, P V; Faisal, M; Ross, P S; Grasman, K A; Zelikoff, J

    1997-05-01

    The potential for chemicals to adversely affect human immunologic health has traditionally been evaluated in rodents, under laboratory conditions. These laboratory studies have generated valuable hazard identification and immunotoxicologic mechanism data; however, genetically diverse populations exposed in the wild may better reflect both human exposure conditions and may provide insight into potential immunotoxic effects in humans. In addition, comparative studies of species occupying reference and impacted sites provide important information on the effects of environmental pollution on the immunologic health of wildlife populations. In this symposium overview, Peter Hodson describes physiological changes in fish collected above or below the outflows of paper mills discharging effluent from the bleaching process (BKME). Effects attributable to BKME were identified, as were physiological changes attributable to other environmental factors. In this context, he discussed the problems of identifying true cause and effect relationships in field studies. Mohamed Faisal described changes in immune function of fish collected from areas with high levels of polyaromatic hydrocarbon contamination. His studies identified a contaminant-related decreases in the ability of anterior kidney leukocytes to bind to and kill tumor cell line targets, as well as changes in lymphocyte proliferation in response to mitogens. Altered proliferative responses of fish from the contaminated site were partially reversed by maintaining fish in water from the reference site. Peter Ross described studies in which harbor seals were fed herring obtained from relatively clean (Atlantic Ocean) and contaminated (Baltic Sea) waters. Decreased natural killer cell activity and lymphoproliferative responses to T and B cell mitogens, as well as depressed antibody and delayed hypersensitivity responses to injected antigens, were identified in seals fed contaminated herring. In laboratory studies, it was

  13. Interactions of gold nanoparticles with freshwater aquatic macrophytes are size and species dependent.

    PubMed

    Glenn, J Brad; White, Sarah A; Klaine, Stephen J

    2012-01-01

    The partitioning of 4- and 18-nm gold nanoparticles (AuNPs) to aquatic macrophytes was investigated in vivo with exposure suspension in well water. Three morphologically distinct aquatic macrophytes were studied. Myriophyllum simulans Orch. and Egeria densa Planch. are submerged aquatic vascular plants, whereas Azolla caroliniana Willd. is a free-floating aquatic fern. Because aquatic plants absorb the majority of their nutrients from the water column, it is logical to hypothesize that they may absorb nanomaterials in suspension, potentially facilitating trophic transfer. Each plant was exposed to two different-sized gold nanospheres at a nominal concentration of 250 µg/L AuNPs for 24 h. Macrophytes were harvested at six time points (1, 3, 6, 12, 18, and 24 h), dried, and then analyzed for gold concentration via inductively coupled plasma-mass spectrometry. Concentrations were normalized to whole-plant dry tissue mass. The present study shows that absorption of AuNPs through root uptake was size and species dependent. Electron microscopy revealed that 4- and 18-nm AuNPs adsorbed to the roots of each species. Root tissue was sectioned, and transmission electron microscopy indicated that 4-nm and 18-nm AuNPs were absorbed by A. caroliniana, whereas only 4-nm AuNPs were absorbed by M. simulans. Egeria densa did not absorb AuNPs of either size. Gold nanoparticles were confirmed in tissue by using energy-dispersive X-ray spectroscopy. Absorption of AuNPs by plants may be a function of the salinity tolerance of each species. PMID:22038861

  14. Phylogenetic placement, species delimitation, and cyanobiont identity of endangered aquatic Peltigera species (lichen-forming Ascomycota, Lecanoromycetes).

    PubMed

    Miadlikowska, Jolanta; Richardson, David; Magain, Nicolas; Ball, Bernard; Anderson, Frances; Cameron, Robert; Lendemer, James; Truong, Camille; Lutzoni, François

    2014-07-11

    • Premise of this study: Aquatic cyanolichens from the genus Peltigera section Hydrothyriae are subject to anthropogenic threats and, therefore, are considered endangered. In this study we addressed the phylogenetic placement of section Hydrothyriae within Peltigera. We delimited species within the section and identified their symbiotic cyanobacteria.• Methods: Species delimitation and population structure were explored using monophyly as a grouping criterion (RAxML) and Structurama based on three protein-coding genes in combination with two nuclear ribosomal loci. The 16S and rbcLX sequences for the cyanobionts were analyzed in the broad phylogenetic context of free-living and symbiotic cyanobacteria.• Key results: We confirm with high confidence the placement of section Hydrothyriae within the monophyletic genus Peltigera; however, its phylogenetic position within the genus remains unsettled. We recovered three distinct monophyletic groups corresponding to three species: P. hydrothyria, P. gowardii s.s., and P. aquatica Miadl. & Lendemer, the latter being formally introduced here. Each species was associated with an exclusive set of Nostoc haplotypes.• Conclusions: The ITS region alone provides sufficient genetic information to distinguish the three morphologically cryptic species within section Hydrothyriae. Section Hydrothyriae seems to be associated with a monophyletic lineage of Nostoc, that has not been found in symbiotic association with other members of Peltigera. Capsosira lowei should be transferred to the genus Nostoc. Potential threats to P. aquatica should be re-examined based on the recognition of two aquatic species in western North America.

  15. Commonly rare and rarely common: comparing population abundance of invasive and native aquatic species.

    PubMed

    Hansen, Gretchen J A; Vander Zanden, M Jake; Blum, Michael J; Clayton, Murray K; Hain, Ernie F; Hauxwell, Jennifer; Izzo, Marit; Kornis, Matthew S; McIntyre, Peter B; Mikulyuk, Alison; Nilsson, Erika; Olden, Julian D; Papeş, Monica; Sharma, Sapna

    2013-01-01

    Invasive species are leading drivers of environmental change. Their impacts are often linked to their population size, but surprisingly little is known about how frequently they achieve high abundances. A nearly universal pattern in ecology is that species are rare in most locations and abundant in a few, generating right-skewed abundance distributions. Here, we use abundance data from over 24,000 populations of 17 invasive and 104 native aquatic species to test whether invasive species differ from native counterparts in statistical patterns of abundance across multiple sites. Invasive species on average reached significantly higher densities than native species and exhibited significantly higher variance. However, invasive and native species did not differ in terms of coefficient of variation, skewness, or kurtosis. Abundance distributions of all species were highly right skewed (skewness>0), meaning both invasive and native species occurred at low densities in most locations where they were present. The average abundance of invasive and native species was 6% and 2%, respectively, of the maximum abundance observed within a taxonomic group. The biological significance of the differences between invasive and native species depends on species-specific relationships between abundance and impact. Recognition of cross-site heterogeneity in population densities brings a new dimension to invasive species management, and may help to refine optimal prevention, containment, control, and eradication strategies.

  16. Commonly Rare and Rarely Common: Comparing Population Abundance of Invasive and Native Aquatic Species

    PubMed Central

    Hansen, Gretchen J. A.; Vander Zanden, M. Jake; Blum, Michael J.; Clayton, Murray K.; Hain, Ernie F.; Hauxwell, Jennifer; Izzo, Marit; Kornis, Matthew S.; McIntyre, Peter B.; Mikulyuk, Alison; Nilsson, Erika; Olden, Julian D.; Papeş, Monica; Sharma, Sapna

    2013-01-01

    Invasive species are leading drivers of environmental change. Their impacts are often linked to their population size, but surprisingly little is known about how frequently they achieve high abundances. A nearly universal pattern in ecology is that species are rare in most locations and abundant in a few, generating right-skewed abundance distributions. Here, we use abundance data from over 24,000 populations of 17 invasive and 104 native aquatic species to test whether invasive species differ from native counterparts in statistical patterns of abundance across multiple sites. Invasive species on average reached significantly higher densities than native species and exhibited significantly higher variance. However, invasive and native species did not differ in terms of coefficient of variation, skewness, or kurtosis. Abundance distributions of all species were highly right skewed (skewness>0), meaning both invasive and native species occurred at low densities in most locations where they were present. The average abundance of invasive and native species was 6% and 2%, respectively, of the maximum abundance observed within a taxonomic group. The biological significance of the differences between invasive and native species depends on species-specific relationships between abundance and impact. Recognition of cross-site heterogeneity in population densities brings a new dimension to invasive species management, and may help to refine optimal prevention, containment, control, and eradication strategies. PMID:24194883

  17. Commonly rare and rarely common: comparing population abundance of invasive and native aquatic species.

    PubMed

    Hansen, Gretchen J A; Vander Zanden, M Jake; Blum, Michael J; Clayton, Murray K; Hain, Ernie F; Hauxwell, Jennifer; Izzo, Marit; Kornis, Matthew S; McIntyre, Peter B; Mikulyuk, Alison; Nilsson, Erika; Olden, Julian D; Papeş, Monica; Sharma, Sapna

    2013-01-01

    Invasive species are leading drivers of environmental change. Their impacts are often linked to their population size, but surprisingly little is known about how frequently they achieve high abundances. A nearly universal pattern in ecology is that species are rare in most locations and abundant in a few, generating right-skewed abundance distributions. Here, we use abundance data from over 24,000 populations of 17 invasive and 104 native aquatic species to test whether invasive species differ from native counterparts in statistical patterns of abundance across multiple sites. Invasive species on average reached significantly higher densities than native species and exhibited significantly higher variance. However, invasive and native species did not differ in terms of coefficient of variation, skewness, or kurtosis. Abundance distributions of all species were highly right skewed (skewness>0), meaning both invasive and native species occurred at low densities in most locations where they were present. The average abundance of invasive and native species was 6% and 2%, respectively, of the maximum abundance observed within a taxonomic group. The biological significance of the differences between invasive and native species depends on species-specific relationships between abundance and impact. Recognition of cross-site heterogeneity in population densities brings a new dimension to invasive species management, and may help to refine optimal prevention, containment, control, and eradication strategies. PMID:24194883

  18. Biodegradation of pesticides using fungi species found in the aquatic environment.

    PubMed

    Oliveira, B R; Penetra, A; Cardoso, V V; Benoliel, M J; Barreto Crespo, M T; Samson, R A; Pereira, V J

    2015-08-01

    Relatively limited attention has been given to the presence of fungi in the aquatic environment compared to their occurrence in other matrices. Taking advantage and recognizing the biodegradable capabilities of fungi is important, since these organisms may produce many potent enzymes capable of degrading toxic pollutants. Therefore, the aim of this study was to evaluate the potential ability of some species of filamentous fungi that occur in the aquatic environment to degrade pesticides in untreated surface water. Several laboratory-scale experiments were performed using the natural microbial population present in the aquatic environment as well as spiked fungi isolates that were found to occur in different water matrices, to test the ability of fungi to degrade several pesticides of current concern (atrazine, diuron, isoproturon and chlorfenvinphos). The results obtained in this study showed that, when spiked in sterile natural water, fungi were able to degrade chlorfenvinphos to levels below detection and unable to degrade atrazine, diuron and isoproturon. Penicillium citrinum, Aspergillus fumigatus, Aspergillus terreus and Trichoderma harzianum were found to be able to resist and degrade chlorfenvinphos. These fungi are therefore expected to play an important role in the degradation of this and other pollutants present in the aquatic environment. PMID:25860553

  19. Biodegradation of pesticides using fungi species found in the aquatic environment.

    PubMed

    Oliveira, B R; Penetra, A; Cardoso, V V; Benoliel, M J; Barreto Crespo, M T; Samson, R A; Pereira, V J

    2015-08-01

    Relatively limited attention has been given to the presence of fungi in the aquatic environment compared to their occurrence in other matrices. Taking advantage and recognizing the biodegradable capabilities of fungi is important, since these organisms may produce many potent enzymes capable of degrading toxic pollutants. Therefore, the aim of this study was to evaluate the potential ability of some species of filamentous fungi that occur in the aquatic environment to degrade pesticides in untreated surface water. Several laboratory-scale experiments were performed using the natural microbial population present in the aquatic environment as well as spiked fungi isolates that were found to occur in different water matrices, to test the ability of fungi to degrade several pesticides of current concern (atrazine, diuron, isoproturon and chlorfenvinphos). The results obtained in this study showed that, when spiked in sterile natural water, fungi were able to degrade chlorfenvinphos to levels below detection and unable to degrade atrazine, diuron and isoproturon. Penicillium citrinum, Aspergillus fumigatus, Aspergillus terreus and Trichoderma harzianum were found to be able to resist and degrade chlorfenvinphos. These fungi are therefore expected to play an important role in the degradation of this and other pollutants present in the aquatic environment.

  20. Illegal trade of regulated and protected aquatic species in the Philippines detected by DNA barcoding.

    PubMed

    Asis, Angelli Marie Jacynth M; Lacsamana, Joanne Krisha M; Santos, Mudjekeewis D

    2016-01-01

    Illegal trade has greatly affected marine fish stocks, decreasing fish populations worldwide. Despite having a number of aquatic species being regulated, illegal trade still persists through the transport of dried or processed products and juvenile species trafficking. In this regard, accurate species identification of illegally traded marine fish stocks by DNA barcoding is deemed to be a more efficient method in regulating and monitoring trade than by morphological means which is very difficult due to the absence of key morphological characters in juveniles and processed products. Here, live juvenile eels (elvers) and dried products of sharks and rays confiscated for illegal trade were identified. Twenty out of 23 (87%) randomly selected "elvers" were identified as Anguilla bicolor pacifica and 3 (13%) samples as Anguilla marmorata. On the other hand, 4 out of 11 (36%) of the randomly selected dried samples of sharks and rays were Manta birostris. The rest of the samples were identified as Alopias pelagicus, Taeniura meyeni, Carcharhinus falciformis, Himantura fai and Mobula japonica. These results confirm that wild juvenile eels and species of manta rays are still being caught in the country regardless of its protected status under Philippine and international laws. It is evident that the illegal trade of protected aquatic species is happening in the guise of dried or processed products thus the need to put emphasis on strengthening conservation measures. This study aims to underscore the importance of accurate species identification in such cases of illegal trade and the effectivity of DNA barcoding as a tool to do this.

  1. Seasonal changes in the critical thermal maxima of four species of aquatic insects (Ephemeroptera, Trichoptera).

    PubMed

    Houghton, David C; Shoup, Logan

    2014-08-01

    Seasonal changes in the critical thermal maxima (CTmax) of four species of aquatic insects were determined from February 2012 to February 2013 from a first-order stream in northern Lower Michigan. Three of these species: Stenonema femoratum (Ephemeroptera: Heptageniidae), Hydropsyche slossonae (Trichoptera: Hydropsychidae), and Dolophilodes distinctus (Trichoptera: Philopotamidae) exhibited seasonal changes in CTmax, increasing through the spring and summer and then decreasing into the subsequent fall and winter. CTmax of these species correlated strongly with both the seasonal ambient stream temperature and with a series of different laboratory acclimation temperatures, suggesting that organisms adapt to laboratory acclimation in a similar manner as they adapt to seasonal changes. In contrast, the CTmax of Parapsyche apicalis (Trichoptera: Arctopsychidae) remained constant regardless of ambient or acclimation temperature. All species exhibited greater thermal sensitivity relative to ambient temperature during the summer than the winter. Our study indicates that thermal tolerance patterns can be different among species in the same environment. It also provides the first winter and year-round thermal tolerance data for aquatic insects.

  2. Aquatic insects dealing with dehydration: do desiccation resistance traits differ in species with contrasting habitat preferences?

    PubMed Central

    Velasco, Josefa; Millán, Andrés; Bilton, David T.; Arribas, Paula

    2016-01-01

    Background Desiccation resistance shapes the distribution of terrestrial insects at multiple spatial scales. However, responses to drying stress have been poorly studied in aquatic groups, despite their potential role in constraining their distribution and diversification, particularly in arid and semi-arid regions. Methods We examined desiccation resistance in adults of four congeneric water beetle species (Enochrus, family Hydrophilidae) with contrasting habitat specificity (lentic vs. lotic systems and different salinity optima from fresh- to hypersaline waters). We measured survival, recovery capacity and key traits related to desiccation resistance (fresh mass, % water content, % cuticle content and water loss rate) under controlled exposure to desiccation, and explored their variability within and between species. Results Meso- and hypersaline species were more resistant to desiccation than freshwater and hyposaline ones, showing significantly lower water loss rates and higher water content. No clear patterns in desiccation resistance traits were observed between lotic and lentic species. Intraspecifically, water loss rate was positively related to specimens’ initial % water content, but not to fresh mass or % cuticle content, suggesting that the dynamic mechanism controlling water loss is mainly regulated by the amount of body water available. Discussion Our results support previous hypotheses suggesting that the evolution of desiccation resistance is associated with the colonization of saline habitats by aquatic beetles. The interespecific patterns observed in Enochrus also suggest that freshwater species may be more vulnerable than saline ones to drought intensification expected under climate change in semi-arid regions such as the Mediterranean Basin. PMID:27635346

  3. Aquatic insects dealing with dehydration: do desiccation resistance traits differ in species with contrasting habitat preferences?

    PubMed Central

    Velasco, Josefa; Millán, Andrés; Bilton, David T.; Arribas, Paula

    2016-01-01

    Background Desiccation resistance shapes the distribution of terrestrial insects at multiple spatial scales. However, responses to drying stress have been poorly studied in aquatic groups, despite their potential role in constraining their distribution and diversification, particularly in arid and semi-arid regions. Methods We examined desiccation resistance in adults of four congeneric water beetle species (Enochrus, family Hydrophilidae) with contrasting habitat specificity (lentic vs. lotic systems and different salinity optima from fresh- to hypersaline waters). We measured survival, recovery capacity and key traits related to desiccation resistance (fresh mass, % water content, % cuticle content and water loss rate) under controlled exposure to desiccation, and explored their variability within and between species. Results Meso- and hypersaline species were more resistant to desiccation than freshwater and hyposaline ones, showing significantly lower water loss rates and higher water content. No clear patterns in desiccation resistance traits were observed between lotic and lentic species. Intraspecifically, water loss rate was positively related to specimens’ initial % water content, but not to fresh mass or % cuticle content, suggesting that the dynamic mechanism controlling water loss is mainly regulated by the amount of body water available. Discussion Our results support previous hypotheses suggesting that the evolution of desiccation resistance is associated with the colonization of saline habitats by aquatic beetles. The interespecific patterns observed in Enochrus also suggest that freshwater species may be more vulnerable than saline ones to drought intensification expected under climate change in semi-arid regions such as the Mediterranean Basin.

  4. The neocortex of cetaceans: cytoarchitecture and comparison with other aquatic and terrestrial species.

    PubMed

    Butti, Camilla; Raghanti, Mary Ann; Sherwood, Chet C; Hof, Patrick R

    2011-04-01

    The evolutionary process of readaptation to the aquatic environment was accompanied by extreme anatomical and physiological changes in the brain. This review discusses cortical specializations in the three major lineages of marine mammals in comparison to related terrestrial and semiaquatic species. Different groups of marine mammals adopted a wide range of strategies to cope with the challenges of aquatic living. Cetaceans and hippopotamids possess a completely agranular neocortex in contrast to phocids and sirenians; vertical modules are observed in deep layers V and VI in manatees, cetaceans, phocids, and hippopotamids, but in different cortical areas; and clustering in layer II appears in the insular cortex of hippopotamids, phocids, and cetaceans. Finally, von Economo neurons are present in cetaceans, hippopotamids, sirenians, and some phocids, with specific, yet different, cortical distributions. The interpretation of the evolutionary and functional significance of such specializations, and their relationships with the degrees of adaptation to the aquatic environment and phylogeny, remain difficult to trace, at least until comprehensive data, including representative species from all of the major mammalian families, become available. PMID:21534992

  5. A spatially and temporally explicit, individual-based, life-history and productivity modeling approach for aquatic species

    EPA Science Inventory

    Realized life history expression and productivity in aquatic species, and salmonid fishes in particular, is the result of multiple interacting factors including genetics, habitat, growth potential and condition, and the thermal regime individuals experience, both at critical stag...

  6. Effects of twenty-five compounds on four species of aquatic fungi (Saprolegniales) pathogenic to fish

    USGS Publications Warehouse

    Bailey, T.A.

    1984-01-01

    Four species of aquatic fungi (Achlya flagellata, A. racemosa, Saprolegnia hypogyna, and S. megasperma) were exposed to 25 chemicals representing seven classes of compounds for 15 and 60 min, in an effort to identify potential fungicidal agents for use in fish culture. The antifungal activity of each chemical was compared with that of malachite green, a reference compound with known fungicidal properties but not registered for fishery use. Six compounds which inhibited fungal growth on artificial media at concentrations of < 100 mg/l (listed in order of decreasing antifungal activity) were the cationics Du-terA? and copper oxychloride sulfate, the amine LesanA?, the amide BAS-389-O1F and the cationics CuprimyxinA? and RoccalA? II. Certain chemicals from these classes of compounds may have promise as aquatic fungicides.

  7. Are cryptic species a problem for parasitological biological tagging for stock identification of aquatic organisms?

    PubMed

    Bray, Rodney A; Cribb, Thomas H

    2015-01-01

    The effective use of biological tags in stock assessment relies on the reliable identification of the parasites concerned. This may be compromised if cryptic species are not recognized. Here we review what is known about cryptic species in aquatic hosts and its potential importance in this respect. Although strictly cryptic species may be considered as species which can be distinguished only by molecular data, we accept the far looser but more practical definition of species that cannot be readily distinguished morphologically. Cryptic species appear to have been identified most frequently as occurring in separate host species; this is heartening in that this has no significant impact on tagging studies. But cryptic species have occasionally been identified in single hosts sympatrically and are relatively common in geographically distinct populations of the same host species. Ignorance of both kinds of occurrences has the capacity to undermine the reliability of tagging analysis. We review in detail what is known of intra- and interspecific genetic variation over geographical ranges in the trematodes, based on recent molecular studies. Although the existence of cryptic species and evidence of intraspecific variability may appear daunting, we suspect that these complexities will add, and indeed have already added, to the sophistication of the information that can be derived from tagging studies.

  8. Assessment of mechanisms of metal-induced reproductive toxicity in aquatic species as a biomarker of exposure

    SciTech Connect

    Anderson, M.; George, W.; Preslan, J.

    1996-05-02

    This project discusses the following studies: identification and quantitation of heavy metals and petroleum products present in Bayou Trepagnier relative to control sites; assessment of the uptake and bioaccumulation of metals and organic contaminants of interest in aquatic species; establishment and use of polarographic methods for use in metal speciation studies to identify specific chemical forms present in sediments, waters and organism; and evaluation of contaminants on reproductive function of aquatic species as potential biomarkers of exposure. 14 refs.

  9. Toxicity of fluoride to aquatic species and evaluation of toxicity modifying factors.

    PubMed

    Pearcy, Krysta; Elphick, James; Burnett-Seidel, Charlene

    2015-07-01

    The present study was performed to investigate the toxicity of fluoride to a variety of freshwater aquatic organisms and to establish whether water quality variables contribute substantively to modifying its toxicity. Water hardness, chloride, and alkalinity were tested as possible toxicity modifying factors for fluoride using acute toxicity tests with Hyalella azteca and Oncorhynchus mykiss. Chloride appeared to be the major toxicity modifying factor for fluoride in these acute toxicity tests. The chronic toxicity of fluoride was evaluated with a variety of species, including 3 fish (Pimephales promelas, O. mykiss, and Salvelinus namaycush), 3 invertebrates (Ceriodaphnia dubia, H. azteca, and Chironomus dilutus), 1 plant (Lemna minor), and 1 alga (Pseudokirchneriella subcapitata). Hyalella azteca was the most sensitive species overall, and O. mykiss was the most sensitive species of fish. The role of chloride as a toxicity modifying factor was inconsistent between species in the chronic toxicity tests.

  10. Impact of Anthropogenic Noise on Aquatic Animals: From Single Species to Community-Level Effects.

    PubMed

    Sabet, Saeed Shafiei; Neo, Yik Yaw; Slabbekoorn, Hans

    2016-01-01

    Anthropogenic noise underwater is on the rise and may affect aquatic animals of marine and freshwater ecosystems. Many recent studies concern some sort of impact assessment of a single species. Few studies addressed the noise impact on species interactions underwater, whereas there are some studies that address community-level impact but only on land in air. Key processes such as predator-prey or competitor interactions may be affected by the masking of auditory cues, noise-related disturbance, or attentional interference. Noise-associated changes in these interactions can cause shifts in species abundance and modify communities, leading to fundamental ecosystem changes. To gain further insight into the mechanism and generality of earlier findings, we investigated the impact on both a predator and a prey species in captivity, zebrafish (Danio rerio) preying on waterfleas (Daphnia magna). PMID:26611055

  11. Toxicity of fluoride to aquatic species and evaluation of toxicity modifying factors.

    PubMed

    Pearcy, Krysta; Elphick, James; Burnett-Seidel, Charlene

    2015-07-01

    The present study was performed to investigate the toxicity of fluoride to a variety of freshwater aquatic organisms and to establish whether water quality variables contribute substantively to modifying its toxicity. Water hardness, chloride, and alkalinity were tested as possible toxicity modifying factors for fluoride using acute toxicity tests with Hyalella azteca and Oncorhynchus mykiss. Chloride appeared to be the major toxicity modifying factor for fluoride in these acute toxicity tests. The chronic toxicity of fluoride was evaluated with a variety of species, including 3 fish (Pimephales promelas, O. mykiss, and Salvelinus namaycush), 3 invertebrates (Ceriodaphnia dubia, H. azteca, and Chironomus dilutus), 1 plant (Lemna minor), and 1 alga (Pseudokirchneriella subcapitata). Hyalella azteca was the most sensitive species overall, and O. mykiss was the most sensitive species of fish. The role of chloride as a toxicity modifying factor was inconsistent between species in the chronic toxicity tests. PMID:25732700

  12. Managing aquatic species of conservation concern in the face of climate change and invasive species.

    PubMed

    Rahel, Frank J; Bierwagen, Britta; Taniguchi, Yoshinori

    2008-06-01

    The difficult task of managing species of conservation concern is likely to become even more challenging due to the interaction of climate change and invasive species. In addition to direct effects on habitat quality, climate change will foster the expansion of invasive species into new areas and magnify the effects of invasive species already present by altering competitive dominance, increasing predation rates, and enhancing the virulence of diseases. In some cases parapatric species may expand into new habitats and have detrimental effects that are similar to those of invading non-native species. The traditional strategy of isolating imperiled species in reserves may not be adequate if habitat conditions change beyond historic ranges or in ways that favor invasive species. The consequences of climate change will require a more active management paradigm that includes implementing habitat improvements that reduce the effects of climate change and creating migration barriers that prevent an influx of invasive species. Other management actions that should be considered include providing dispersal corridors that allow species to track environmental changes, translocating species to newly suitable habitats where migration is not possible, and developing action plans for the early detection and eradication of new invasive species.

  13. Managing aquatic species of conservation concern in the face of climate change and invasive species.

    PubMed

    Rahel, Frank J; Bierwagen, Britta; Taniguchi, Yoshinori

    2008-06-01

    The difficult task of managing species of conservation concern is likely to become even more challenging due to the interaction of climate change and invasive species. In addition to direct effects on habitat quality, climate change will foster the expansion of invasive species into new areas and magnify the effects of invasive species already present by altering competitive dominance, increasing predation rates, and enhancing the virulence of diseases. In some cases parapatric species may expand into new habitats and have detrimental effects that are similar to those of invading non-native species. The traditional strategy of isolating imperiled species in reserves may not be adequate if habitat conditions change beyond historic ranges or in ways that favor invasive species. The consequences of climate change will require a more active management paradigm that includes implementing habitat improvements that reduce the effects of climate change and creating migration barriers that prevent an influx of invasive species. Other management actions that should be considered include providing dispersal corridors that allow species to track environmental changes, translocating species to newly suitable habitats where migration is not possible, and developing action plans for the early detection and eradication of new invasive species. PMID:18577084

  14. Monitoring hydrilla using two RAPD procedures and the nonindigenous aquatic species database

    USGS Publications Warehouse

    Madeira, Paul T.; Jacono, C.C.; Van, Thai K.

    2000-01-01

    Hydrilla (Hydrilla verticillata (L.f.) Royle), an invasive aquatic weed, continues to spread to new regions in the United States. Two biotypes, one a female dioecious and the other monoecious have been identified. Management of the spread of hydrilla requires understanding the mechanisms of introduction and transport, an ability to map and make available information on distribution, and tools to distinguish the known U.S. biotypes as well as potential new introductions. Review of the literature and discussions with aquatic scientists and resource managers point to the aquarium and water garden plant trades as the primary past mechanism for the regional dispersal of hydrilla while local dispersal is primarily carried out by other mechanisms such as boat traffic, intentional introductions, and waterfowl. The Nonindigenous Aquatic Species (NAS) database is presented as a tool for assembling, geo-referencing, and making available information on the distribution of hydrilla. A map of the current range of dioecious and monoecious hydrilla by drainage is presented. Four hydrilla samples, taken from three discrete, non-contiguous regions (Pennsylvania, Connecticut, and Washington State) were examined using two RAPD assays. The first, generated using primer Operon G17, and capable of distinguishing the dioecious and monoecious U.S. biotypes, indicated all four samples were of the monoecious biotype. Results of the second assay using the Stoffel fragment and 5 primers, produced 111 markers, indicated that these samples do not represent new foreign introductions. The differences in the monoecious and dioecious growth habits and management are discussed.

  15. Assessing contaminant sensitivity of endangered and threatened aquatic species: Part I. Acute toxicity of five chemicals

    USGS Publications Warehouse

    Dwyer, F.J.; Mayer, F.L.; Sappington, L.C.; Buckler, D.R.; Bridges, C.M.; Greer, I.E.; Hardesty, D.K.; Henke, C.E.; Ingersoll, C.G.; Kunz, J.L.; Whites, D.W.; Augspurger, T.; Mount, D.R.; Hattala, K.; Neuderfer, G.N.

    2005-01-01

    Assessment of contaminant impacts to federally identified endangered, threatened and candidate, and state-identified endangered species (collectively referred to as "listed" species) requires understanding of a species' sensitivities to particular chemicals. The most direct approach would be to determine the sensitivity of a listed species to a particular contaminant or perturbation. An indirect approach for aquatic species would be application of toxicity data obtained from standard test procedures and species commonly used in laboratory toxicity tests. Common test species (fathead minnow, Pimephales promelas; sheepshead minnow, Cyprinodon variegatus; and rainbow trout, Oncorhynchus mykiss) and 17 listed or closely related species were tested in acute 96-hour water exposures with five chemicals (carbaryl, copper, 4-nonylphenol, pentachlorophenol, and permethrin) representing a broad range of toxic modes of action. No single species was the most sensitive to all chemicals. For the three standard test species evaluated, the rainbow trout was more sensitive than either the fathead minnow or sheepshead minnow and was equal to or more sensitive than listed and related species 81% of the time. To estimate an LC50 for a listed species, a factor of 0.63 can be applied to the geometric mean LC50 of rainbow trout toxicity data, and more conservative factors can be determined using variance estimates (0.46 based on 1 SD of the mean and 0.33 based on 2 SD of the mean). Additionally, a low- or no-acute effect concentration can be estimated by multiplying the respective LC50 by a factor of approximately 0.56, which supports the United States Environmental Protection Agency approach of multiplying the final acute value by 0.5 (division by 2). When captive or locally abundant populations of listed fish are available, consideration should be given to direct testing. When direct toxicity testing cannot be performed, approaches for developing protective measures using common test

  16. Predicting aquatic toxicities of chemical pesticides in multiple test species using nonlinear QSTR modeling approaches.

    PubMed

    Basant, Nikita; Gupta, Shikha; Singh, Kunwar P

    2015-11-01

    In this study, we established nonlinear quantitative-structure toxicity relationship (QSTR) models for predicting the toxicities of chemical pesticides in multiple aquatic test species following the OECD (Organization for Economic Cooperation and Development) guidelines. The decision tree forest (DTF) and decision tree boost (DTB) based QSTR models were constructed using a pesticides toxicity dataset in Selenastrum capricornutum and a set of six descriptors. Other six toxicity data sets were used for external validation of the constructed QSTRs. Global QSTR models were also constructed using the combined dataset of all the seven species. The diversity in chemical structures and nonlinearity in the data were evaluated. Model validation was performed deriving several statistical coefficients for the test data and the prediction and generalization abilities of the QSTRs were evaluated. Both the QSTR models identified WPSA1 (weighted charged partial positive surface area) as the most influential descriptor. The DTF and DTB QSTRs performed relatively better than the single decision tree (SDT) and support vector machines (SVM) models used as a benchmark here and yielded R(2) of 0.886 and 0.964 between the measured and predicted toxicity values in the complete dataset (S. capricornutum). The QSTR models applied to six other aquatic species toxicity data yielded R(2) of >0.92 (DTF) and >0.97 (DTB), respectively. The prediction accuracies of the global models were comparable with those of the S. capricornutum models. The results suggest for the appropriateness of the developed QSTR models to reliably predict the aquatic toxicity of chemicals and can be used for regulatory purpose.

  17. Predicting aquatic toxicities of chemical pesticides in multiple test species using nonlinear QSTR modeling approaches.

    PubMed

    Basant, Nikita; Gupta, Shikha; Singh, Kunwar P

    2015-11-01

    In this study, we established nonlinear quantitative-structure toxicity relationship (QSTR) models for predicting the toxicities of chemical pesticides in multiple aquatic test species following the OECD (Organization for Economic Cooperation and Development) guidelines. The decision tree forest (DTF) and decision tree boost (DTB) based QSTR models were constructed using a pesticides toxicity dataset in Selenastrum capricornutum and a set of six descriptors. Other six toxicity data sets were used for external validation of the constructed QSTRs. Global QSTR models were also constructed using the combined dataset of all the seven species. The diversity in chemical structures and nonlinearity in the data were evaluated. Model validation was performed deriving several statistical coefficients for the test data and the prediction and generalization abilities of the QSTRs were evaluated. Both the QSTR models identified WPSA1 (weighted charged partial positive surface area) as the most influential descriptor. The DTF and DTB QSTRs performed relatively better than the single decision tree (SDT) and support vector machines (SVM) models used as a benchmark here and yielded R(2) of 0.886 and 0.964 between the measured and predicted toxicity values in the complete dataset (S. capricornutum). The QSTR models applied to six other aquatic species toxicity data yielded R(2) of >0.92 (DTF) and >0.97 (DTB), respectively. The prediction accuracies of the global models were comparable with those of the S. capricornutum models. The results suggest for the appropriateness of the developed QSTR models to reliably predict the aquatic toxicity of chemicals and can be used for regulatory purpose. PMID:26142614

  18. Oxygen stress reduces zoospore survival of Phytophthora species in a simulated aquatic system

    PubMed Central

    2014-01-01

    Background The genus Phytophthora includes a group of agriculturally important pathogens and they are commonly regarded as water molds. They produce motile zoospores that can move via water currents and on their own locomotion in aquatic environments. However, zoosporic response to dissolved oxygen, an important water quality parameter, is not known. Like other water quality parameters, dissolved oxygen concentration in irrigation reservoirs fluctuates dramatically over time. The aim of this study was to determine whether and how zoospore survival may be affected by elevated and low concentrations of dissolved oxygen in water to better understand the aquatic biology of these pathogens in irrigation reservoirs. Results Zoospores of P. megasperma, P. nicotianae, P. pini and P. tropicalis were assessed for survival in 10% Hoagland’s solution at a range of dissolved concentrations from 0.9 to 20.1 mg L-1 for up to seven exposure times from 0 to 72 h. Zoospore survival was measured by resultant colony counts per ml. Zoospores of these species survived the best in control Hoagland’s solution at dissolved oxygen concentrations of 5.3 to 5.6 mg L-1. Zoospore survival rates decreased with increasing and decreasing concentration of dissolved oxygen, depending upon Phytophthora species and exposure time. Overall, P. megasperma and P. pini are less sensitive than P. nicotianae and P. tropicalis to hyperoxia and hypoxia conditions. Conclusion Zoospores in the control solution declined over time and this natural decline process was enhanced under hyperoxia and hypoxia conditions. These findings suggest that dramatic fluctuations of dissolved oxygen in irrigation reservoirs contribute to the population decline of Phytophthora species along the water path in the same reservoirs. These findings advanced our understanding of the aquatic ecology of these pathogens in irrigation reservoirs. They also provided a basis for pathogen risk mitigation by prolonging the turnover

  19. Capacity of management plans for aquatic invasive species to integrate climate change.

    PubMed

    Bierwagen, Britta G; Thomas, Roxanne; Kane, Austin

    2008-06-01

    The consequences of climate change will affect aquatic ecosystems, including aquatic invasive species (AIS) that are already affecting these ecosystems. Effects on AIS include range shifts and more frequent overwintering of species. These effects may create new challenges for AIS management. We examined available U.S. state AIS management plans to assess each program's capacity to adapt to climate-change effects. We scored the adaptive capacity of AIS management plans on the basis of whether they addressed potential impacts resulting from climate change; demonstrated a capacity to adapt to changing conditions; provided for monitoring strategies; provided for plan revisions; and described funding for implementation. Most plans did not mention climate change specifically, but some did acknowledge climatic boundaries of species and ecosystem sensitivities to changing conditions. Just under half the plans mentioned changing environmental conditions as a factor, most frequently as part of research activities. Activities associated with monitoring showed the highest capacity to include information on changing conditions, and future revisions to management plans are likely to be the easiest avenue through which to address climate-change effects on AIS management activities. Our results show that programs have the capacity to incorporate information about climate-change effects and that the adaptive-management framework may be an appropriate approach.

  20. Impacts of aquatic nonindigenous invasive species on the Lake Erie ecosystem

    USGS Publications Warehouse

    Austen, Madeline J.W.; Ciborowski, Jan J.H.; Corkum, Lynda D.; Johnson, Tim B.; MacIsaac, Hugh J.; Metcalfe-Smith, Janice L.; Schloesser, Donald W.; George, Sandra E.

    2002-01-01

    Lake Erie is particularly vulnerable to the introduction and establishment of aquatic nonindigenous invasive species (NIS) populations. A minimum of 144 aquatic NIS have been recorded in the Lake Erie basin including several species [e.g., Eurasian watermilfoil (Myriophyllum spicatum); zebra mussel (Dreissena polymorpha); quagga mussel (Dreissena bugensis); an amphipod (Echinogammarus ischnus); round goby (Neogobius melanostomus); and sea lamprey (Petromyzon marinus)] that have had discernible impacts on the lake's ecology. NIS pose threats to the Lake Erie ecosystem for a variety of reasons including their ability to proliferate quickly, compete with native species, and transfer contaminants (e.g., PCBs) and disease through the food web. Six of the 14 beneficial use impairments listed in Annex 2 of the Great Lakes Water Quality Agreement are impaired in Lake Erie, in part as a result of the introduction of NIS. The Lake Erie Lakewide Management Plan (LaMP) has adopted an ecosystem approach to restore beneficial use impairments in the lake. Furthermore, a research consortium, known as the Lake Erie Millennium Network, is working alongside the LaMP, to address research problems regarding NIS, the loss of habitat, and the role of contaminants in the Lake Erie ecosystem.

  1. Aquatic Biodiversity in the Amazon: Habitat Specialization and Geographic Isolation Promote Species Richness

    PubMed Central

    Albert, James S.; Carvalho, Tiago P.; Petry, Paulo; Holder, Meghan A.; Maxime, Emmanuel L.; Espino, Jessica; Corahua, Isabel; Quispe, Roberto; Rengifo, Blanca; Ortega, Hernan; Reis, Roberto E.

    2011-01-01

    Simple Summary The immense rainforest ecosystems of tropical America represent some of the greatest concentrations of biodiversity on the planet. Prominent among these are evolutionary radiations of freshwater fishes, including electric eels, piranhas, stingrays, and a myriad of small-bodied and colorful tetras, cichlids, and armored catfishes. In all, the many thousands of these forms account for nearly 10% of all the vertebrate species on Earth. This article explores the complimentary roles that ecological and geographic filters play in limiting dispersal in aquatic species, and how these factors contribute to the accumulation of species richness over broad geographic and evolutionary time scales. Abstract The Neotropical freshwater ichthyofauna has among the highest species richness and density of any vertebrate fauna on Earth, with more than 5,600 species compressed into less than 12% of the world's land surface area, and less than 0.002% of the world's total liquid water supply. How have so many species come to co-exist in such a small amount of total habitat space? Here we report results of an aquatic faunal survey of the Fitzcarrald region in southeastern Peru, an area of low-elevation upland (200–500 m above sea level) rainforest in the Western Amazon, that straddles the headwaters of four large Amazonian tributaries; the Juruá (Yurúa), Ucayali, Purús, and Madre de Dios rivers. All measures of fish species diversity in this region are high; there is high alpha diversity with many species coexisting in the same locality, high beta diversity with high turnover between habitats, and high gamma diversity with high turnover between adjacent tributary basins. Current data show little species endemism, and no known examples of sympatric sister species, within the Fitzcarrald region, suggesting a lack of localized or recent adaptive divergences. These results support the hypothesis that the fish species of the Fitzcarrald region are relatively ancient

  2. Endangered species: where leatherback turtles meet fisheries.

    PubMed

    Ferraroli, Sandra; Georges, Jean-Yves; Gaspar, Philippe; Le Maho, Yvon

    2004-06-01

    The dramatic worldwide decline in populations of the leatherback turtle (Dermochelys coriacea) is largely due to the high mortality associated with their interaction with fisheries, so a reduction of this overlap is critical to their survival. The discovery of narrow migration corridors used by the leatherbacks in the Pacific Ocean raised the possibility of protecting the turtles by restricting fishing in these key areas. Here we use satellite tracking to show that there is no equivalent of these corridors in the North Atlantic Ocean, because the turtles disperse actively over the whole area. But we are able to identify a few 'hot spots' where leatherbacks meet fisheries and where conservation efforts should be focused. PMID:15175741

  3. Illegal trade of regulated and protected aquatic species in the Philippines detected by DNA barcoding.

    PubMed

    Asis, Angelli Marie Jacynth M; Lacsamana, Joanne Krisha M; Santos, Mudjekeewis D

    2016-01-01

    Illegal trade has greatly affected marine fish stocks, decreasing fish populations worldwide. Despite having a number of aquatic species being regulated, illegal trade still persists through the transport of dried or processed products and juvenile species trafficking. In this regard, accurate species identification of illegally traded marine fish stocks by DNA barcoding is deemed to be a more efficient method in regulating and monitoring trade than by morphological means which is very difficult due to the absence of key morphological characters in juveniles and processed products. Here, live juvenile eels (elvers) and dried products of sharks and rays confiscated for illegal trade were identified. Twenty out of 23 (87%) randomly selected "elvers" were identified as Anguilla bicolor pacifica and 3 (13%) samples as Anguilla marmorata. On the other hand, 4 out of 11 (36%) of the randomly selected dried samples of sharks and rays were Manta birostris. The rest of the samples were identified as Alopias pelagicus, Taeniura meyeni, Carcharhinus falciformis, Himantura fai and Mobula japonica. These results confirm that wild juvenile eels and species of manta rays are still being caught in the country regardless of its protected status under Philippine and international laws. It is evident that the illegal trade of protected aquatic species is happening in the guise of dried or processed products thus the need to put emphasis on strengthening conservation measures. This study aims to underscore the importance of accurate species identification in such cases of illegal trade and the effectivity of DNA barcoding as a tool to do this. PMID:24841434

  4. Development of aquatic toxicity benchmarks for oil products using species sensitivity distributions.

    PubMed

    Barron, Mace G; Hemmer, Michael J; Jackson, Crystal R

    2013-10-01

    Determining the sensitivity of a diversity of species to spilled oil and chemically dispersed oil continues to be a significant challenge in spill response and impact assessment. We used standardized tests from the literature to develop species sensitivity distributions (SSDs) of acute aquatic toxicity values for several petroleum products and 2 Corexit oil dispersants. Fifth percentile hazard concentrations (HC5s) were computed from the SSDs and used to assess relative oil product toxicity and in evaluating the feasibility of establishing toxicity benchmarks for a community of species. The sensitivity of mysids (Americamysis bahia) and silversides (Menidia beryllina) were evaluated within the SSDs to determine if these common test species were appropriate surrogates for a broader range of species. In general, SSD development was limited by the availability of acute toxicity values that met standardization criteria for a diversity of species. Pooled SSDs were also developed for crude oil and Corexit dispersants because there was only small variability in the HC5s among the individual oil or dispersant products. The sensitivity of mysids and silversides varied across the oil and dispersant products, with the majority of toxicity values greater than the HC5. Application of SSDs appears to be a reasonable approach to developing oil product toxicity benchmarks, but additional toxicity data are needed for a larger range of species conducted under standardized test conditions. PMID:23554001

  5. Development of aquatic toxicity benchmarks for oil products using species sensitivity distributions.

    PubMed

    Barron, Mace G; Hemmer, Michael J; Jackson, Crystal R

    2013-10-01

    Determining the sensitivity of a diversity of species to spilled oil and chemically dispersed oil continues to be a significant challenge in spill response and impact assessment. We used standardized tests from the literature to develop species sensitivity distributions (SSDs) of acute aquatic toxicity values for several petroleum products and 2 Corexit oil dispersants. Fifth percentile hazard concentrations (HC5s) were computed from the SSDs and used to assess relative oil product toxicity and in evaluating the feasibility of establishing toxicity benchmarks for a community of species. The sensitivity of mysids (Americamysis bahia) and silversides (Menidia beryllina) were evaluated within the SSDs to determine if these common test species were appropriate surrogates for a broader range of species. In general, SSD development was limited by the availability of acute toxicity values that met standardization criteria for a diversity of species. Pooled SSDs were also developed for crude oil and Corexit dispersants because there was only small variability in the HC5s among the individual oil or dispersant products. The sensitivity of mysids and silversides varied across the oil and dispersant products, with the majority of toxicity values greater than the HC5. Application of SSDs appears to be a reasonable approach to developing oil product toxicity benchmarks, but additional toxicity data are needed for a larger range of species conducted under standardized test conditions.

  6. UV-induced cell damage is species-specific among aquatic phagotrophic protists.

    PubMed

    Sommaruga, R; Buma, A G

    2000-01-01

    The sensitivity to ultraviolet radiation (UVR, 280-400 nm) of ten species of freshwater and marine phagotrophic protists was assessed in short-term (4 h) laboratory experiments. Changes in the motility and morphology of the cells, as well as direct quantification of DNA damage, were evaluated. The net amount of cyclobutane pyrimidine dimers formed after exposure of the organisms to a weighted dose (Setlow DNA normalized at 300 nm) of 1.7 kJ m(-2) was quantified by an immunoassay using a monoclonal specific antibody directed against thymine dimers (T<>Ts). This is the first application of this method to aquatic protists. The results indicated that marine and freshwater heterotrophic nanoflagellates, representatives from the order Kinetoplastida (Bodo caudatus and Bodo saltans, respectively) accumulate significantly higher DNA damage than protists representatives of the orders Chrysomonadida, Cryptomonadida or Scuticociliatida. The high proportion of A:T bases in the unique kinetoplast DNA, may explain the higher accumulation of T<>Ts found in bodonids. Experiments made with B. saltans to study the dynamics of DNA damage accumulation in the presence of UVR and photorepairing light, indicated that the mechanisms of DNA repair in this species are very inefficient. Furthermore, the dramatic changes observed in the cell morphology of B. saltans probably compromise its recovery. Our results show that sensitivity to UVR among aquatic phagotrophic protists is species-specific and that different cell targets are affected differently among species. While DNA damage in B. saltans was accompanied by motility reduction, altered morphology, and finally mortality, this was not observed in other bodonids as well as in the other species tested.

  7. Trichoderma matsushimae and T. aeroaquaticum: two aero-aquatic species with Pseudaegerita-like propagules.

    PubMed

    Yamaguchi, Kaoru; Tsurumi, Yasuhisa; Suzuki, Rieko; Chuaseeharonnachai, Charuwan; Sri-Indrasutdhi, Veera; Boonyuen, Nattawut; Okane, Izumi; Suzuki, Ken-ichiro; Nakagiri, Akira

    2012-01-01

    Four isolates tentatively identified as Pseudaegerita matsushimae on the basis of the morphology of bulbil-like propagules were collected from substrates submerged in water in Thailand and Japan. In culture studies the two Thai isolates were found to produce phialoconidia on conidiogenous cells and phialoconidiophores whose morphology was similar to that of Trichoderma. Phylogenetic analysis based on D1/D2 regions of LSU rDNA sequences showed that the four isolates were nested in Hypocrea/Trichoderma (Hypocreales) while P. corticalis, the type species of Pseudaegerita, belongs to Hyaloscypha (Helotiales). Preliminary analysis by ISTH Web tools based on 5.8S-ITS rDNA and phylogenetic analysis based on rpb2 and tef1-int4 genes showed that the isolates have specific sequences of Trichoderma (anchors 1-5) and belong to the Hamatum clade but they grouped apart from any known species of Trichoderma. The sequences of the tef1-int4 gene, which were amplified from the authentic specimen of P. matsushimae (IMI 266915), also showed that it belongs to the Hamatum clade closely clustering with T. yunnanense but separate from our four isolates. The morphology of P. matsushimae (IMI 266915), especially the sizes of phialides and phialoconidia, were different from T. yunnanense. Thus, we conclude that IMI 266915 and our isolates are to be assigned to two different species in the Hamatum clade of Trichoderma, although both species have similar morphology of bulbils and phialoconidia. Morphology and molecular data revealed that P. matsushimae should be assigned to the genus Trichoderma as T. matsushimae and the Thai and Japanese isolates are placed in T. aeroaquaticum sp. nov. This finding supports the interpretation that aero-aquatic fungi have evolved from terrestrial fungi. We assume that these fungi probably were derived from typically soil-inhabiting species of Trichoderma; an adaptation to aquatic environments is shown by formation of bulbil-like propagules floating on water.

  8. Interaction of species traits and environmental disturbance predicts invasion success of aquatic microorganisms.

    PubMed

    Mächler, Elvira; Altermatt, Florian

    2012-01-01

    Factors such as increased mobility of humans, global trade and climate change are affecting the range of many species, and cause large-scale translocations of species beyond their native range. Many introduced species have a strong negative influence on the new local environment and lead to high economic costs. There is a strong interest to understand why some species are successful in invading new environments and others not. Most of our understanding and generalizations thereof, however, are based on studies of plants and animals, and little is known on invasion processes of microorganisms. We conducted a microcosm experiment to understand factors promoting the success of biological invasions of aquatic microorganisms. In a controlled lab experiment, protist and rotifer species originally isolated in North America invaded into a natural, field-collected community of microorganisms of European origin. To identify the importance of environmental disturbances on invasion success, we either repeatedly disturbed the local patches, or kept them as undisturbed controls. We measured both short-term establishment and long-term invasion success, and correlated it with species-specific life-history traits. We found that environmental disturbances significantly affected invasion success. Depending on the invading species' identity, disturbances were either promoting or decreasing invasion success. The interaction between habitat disturbance and species identity was especially pronounced for long-term invasion success. Growth rate was the most important trait promoting invasion success, especially when the species invaded into a disturbed local community. We conclude that neither species traits nor environmental factors alone conclusively predict invasion success, but an integration of both of them is necessary.

  9. Causes of Discordance between Allometries at and above Species Level: An Example with Aquatic Beetles.

    PubMed

    Higginson, Dawn M; Badyaev, Alexander V; Segraves, Kari A; Pitnick, Scott

    2015-08-01

    Covariation among organismal traits is nearly universal, occurring both within and among species (static and evolutionary allometry, respectively). If conserved developmental processes produce similarity in static and evolutionary allometry, then when species differ in development, it should be expressed in discordance between allometries. Here, we investigate whether rapidly evolving developmental processes result in discordant static and evolutionary allometries attributable to trade-offs in resource acquisition, allocation, or growth across 30 species of aquatic beetles. The highly divergent sperm phenotypes of these beetles might be an important contributor to allometric evolution of testis and accessory gland mass through altered requirements for the production of sperm and seminal fluids. We documented extensive discordance between static and evolutionary allometries, indicating that allometric relationships are flexibly modified over short time periods but subject to constraint over longer time spans. Among species, sperm phenotype did not influence relative investment in accessory glands but was weakly associated with investment in testes. Furthermore, except when sperm were long and simple, sperm phenotype was not associated with species-specific modification of the allometry of testis/accessory gland mass and body size. Our results demonstrate the utility of allometric discordance to infer species differences in the provisioning and growth of concurrently developing traits.

  10. Look Back at the U.S. Department of Energy's Aquatic Species Program: Biodiesel from Algae; Close-Out Report

    SciTech Connect

    Sheehan, J.; Dunahay, T.; Benemann, J.; Roessler, P.

    1998-07-01

    The Aquatic Species Program was a relatively small research effort intended to look at the use of aquatic plants as sources of energy. Its history dates back to 1978, but much of the research from 1978 to 1982 focused on using algae to produce hydrogen. The program switched emphasis to other transportation fuels, particularly biodiesel, beginning in the early 1980's. This report summarizes the research activities carried out from 1980 to 1996, with an emphasis on algae for biodiesel production.

  11. Respiration and photosynthesis of bladders and leaves of aquatic utricularia species.

    PubMed

    Adamec, L

    2006-11-01

    In aquatic species of carnivorous utricularia, about 10 - 50 % of the total biomass consists of bladders. Utricularia bladders are physiologically very active organs though their chlorophyll content may greatly be reduced. To specify energetic costs of carnivory, respiration (RD) and net photosynthetic rate (PN) were compared in bladders and leaves or shoot segments of six aquatic utricularia species with differentiated (U. ochroleuca, U. intermedia, U. floridana) or non-differentiated shoots (U. vulgaris, U. australis, U. bremii) under optimum conditions (20 degrees C, [CO (2)] 0.20 mM, 400 micromol m (-2) s (-1) PAR). RD of bladders of six utricularia species (5.1 - 8.6 mmol kg (-1)(FW) h (-1)) was 75 - 200 % greater, than that in leaves in carnivorous or photosynthetic shoots (1.7 - 6.1 mmol kg (-1)(FW) h (-1)). Within individual species, this difference was statistically significant at P < 0.002 - 0.01. However, PN in photosynthetic leaves/shoots (40 - 117 mmol kg (-1)(FW) h (-1)) exceeded that in bladders (5.2 - 14.7 mmol kg (-1)(FW) h (-1)) 7 - 10 times. RD of empty bladders of U. ochroleuca was exactly the same as that in bladders containing prey. Though utricularia bladders are essential for uptake of growth limiting mineral nutrients N and P from prey as the main benefit of carnivory, the current results support previous work showing that bladder function requires greater metabolic (maintenance) cost and very low photosynthetic efficiency (great RD : PN ratio). PMID:17203432

  12. Aquatic Biodiversity in the Amazon: Habitat Specialization and Geographic Isolation Promote Species Richness.

    PubMed

    Albert, James S; Carvalho, Tiago P; Petry, Paulo; Holder, Meghan A; Maxime, Emmanuel L; Espino, Jessica; Corahua, Isabel; Quispe, Roberto; Rengifo, Blanca; Ortega, Hernan; Reis, Roberto E

    2011-01-01

    The Neotropical freshwater ichthyofauna has among the highest species richness and density of any vertebrate fauna on Earth, with more than 5,600 species compressed into less than 12% of the world's land surface area, and less than 0.002% of the world's total liquid water supply. How have so many species come to co-exist in such a small amount of total habitat space? Here we report results of an aquatic faunal survey of the Fitzcarrald region in southeastern Peru, an area of low-elevation upland (200-500 m above sea level) rainforest in the Western Amazon, that straddles the headwaters of four large Amazonian tributaries; the Juruá (Yurúa), Ucayali, Purús, and Madre de Dios rivers. All measures of fish species diversity in this region are high; there is high alpha diversity with many species coexisting in the same locality, high beta diversity with high turnover between habitats, and high gamma diversity with high turnover between adjacent tributary basins. Current data show little species endemism, and no known examples of sympatric sister species, within the Fitzcarrald region, suggesting a lack of localized or recent adaptive divergences. These results support the hypothesis that the fish species of the Fitzcarrald region are relatively ancient, predating the Late Miocene-Pliocene (c. 4 Ma) uplift that isolated its several headwater basins. The results also suggest that habitat specialization (phylogenetic niche conservatism) and geographic isolation (dispersal limitation) have contributed to the maintenance of high species richness in this region of the Amazon Basin. PMID:26486313

  13. Interaction of Species Traits and Environmental Disturbance Predicts Invasion Success of Aquatic Microorganisms

    PubMed Central

    Mächler, Elvira; Altermatt, Florian

    2012-01-01

    Factors such as increased mobility of humans, global trade and climate change are affecting the range of many species, and cause large-scale translocations of species beyond their native range. Many introduced species have a strong negative influence on the new local environment and lead to high economic costs. There is a strong interest to understand why some species are successful in invading new environments and others not. Most of our understanding and generalizations thereof, however, are based on studies of plants and animals, and little is known on invasion processes of microorganisms. We conducted a microcosm experiment to understand factors promoting the success of biological invasions of aquatic microorganisms. In a controlled lab experiment, protist and rotifer species originally isolated in North America invaded into a natural, field-collected community of microorganisms of European origin. To identify the importance of environmental disturbances on invasion success, we either repeatedly disturbed the local patches, or kept them as undisturbed controls. We measured both short-term establishment and long-term invasion success, and correlated it with species-specific life-history traits. We found that environmental disturbances significantly affected invasion success. Depending on the invading species’ identity, disturbances were either promoting or decreasing invasion success. The interaction between habitat disturbance and species identity was especially pronounced for long-term invasion success. Growth rate was the most important trait promoting invasion success, especially when the species invaded into a disturbed local community. We conclude that neither species traits nor environmental factors alone conclusively predict invasion success, but an integration of both of them is necessary. PMID:23028985

  14. Sensitivity and accuracy of DNA based methods used to describe aquatic communities for early detection of invasive fish species

    EPA Science Inventory

    For biomonitoring efforts aimed at early detection of aquatic invasive species (AIS), the ability to detect rare individuals is key and requires accurate species level identification to maintain a low occurrence probability of non-detection errors (failure to detect a present spe...

  15. Effect of environmental contaminants in the Mississippi River Basin on carboxylesterases from four aquatic species

    SciTech Connect

    Jaiswal, R.; Huang, T.; Obih, P.; Hartley, W.

    1995-12-31

    The objectives of this study are to investigate the sensitivity of different classes of esterases in various aquatic species to environmental contaminants and the possible use of these enzymes as biomarkers for monitoring the effects of pollutants. Acetylcholinesterase (AChE), butyrylcholinesterase (BuChE), and the non-specific carboxylesterases (CaE) were analyzed in three fish species, Ictiobus bubalus (small mouth buffalo), Ictiobus cyprinellus (big mouth buffalo) and Lepisosteus oculatus (spotted gar) and the green tree frog, Hyla cinerea. These samples were collected from the Devil`s Swamp Site (DSS), an industrial site known to be highly contaminated at the Mississippi River Basin, and Lake Tunica, a nonindustrial site. ACHE and BuChE activities in the subcellular fractions of liver and brain were significantly lower in fishes and frogs obtained from DSS when compared to the same species obtained from Tunica swamp site. The greatest decrease was observed with ACHE activity in the liver and brain of Ictiobus bubalus from DSS. CaE activity analyzed with p-nitrophenyl acetate was found to be significantly lower in the liver of all three fish species collected from DSS when compared to the same fish species obtained from the Tunica swamp site.

  16. POST-EXERCISE LACTATE PRODUCTION AND METABOLISM IN THREE SPECIES OF AQUATIC AND TERRESTRIAL DECAPOD CRUSTACEANS

    PubMed

    Walsh

    1994-01-01

    Aquatic and terrestrial crustaceans are dependent on both aerobic and anaerobic metabolism for energy production during exercise. Anaerobic energy production is marked by an accumulation of lactate in both muscle tissue and haemolymph, but the metabolic fate of lactate is not clear. Lactate recycling via gluconeogenesis and the potential role of carbonic anhydrase (CA) in supplying bicarbonate for the carboxylation of pyruvate were investigated in three species of decapod crustaceans: Callinectes sapidus (aquatic), Cardisoma guanhumi (semi-terrestrial) and Gecarcinus lateralis (terrestrial). CA activity was found in mitochondria and cytoplasmic fractions of gill, hepatopancreas and muscle of all three species. Significant activities of key enzymes of gluconeogenesis (e.g. pyruvate carboxylase, phosphoenolpyruvate carboxykinase and fructose bisphosphatase), however, could not be detected. Exercise to exhaustion produced a species-specific pattern of accumulation and clearance of lactate in tissue and haemolymph, indicating a differential degree of reliance on anaerobic energy production. Treatment with acetazolamide, a CA inhibitor, did not significantly alter the pattern of lactate dynamics in animals given repeated bouts of exhaustive exercise interspersed with periods of recovery. Injection of [U-14C]lactate resulted in the appearance of label in both muscle glycogen and excreted carbon dioxide, suggesting multiple metabolic fates for lactate. Lactate turnover rates for G. lateralis were similar to those reported for fish. In these animals, gluconeogenesis possibly proceeds via the reversal of pyruvate kinase, or via the typical Cori cycle but so slowly that the uncatalysed supply of bicarbonate is sufficient to keep pace with the low activities of pyruvate carboxylase and the subsequent low rates of pyruvate carboxylation.

  17. Effects of Outreach on the Prevention of Aquatic Invasive Species Spread among Organism-in-Trade Hobbyists

    NASA Astrophysics Data System (ADS)

    Seekamp, Erin; Mayer, Jessica E.; Charlebois, Patrice; Hitzroth, Greg

    2016-11-01

    Releases of aquatic organisms-in-trade by aquarists, water gardeners, and outdoor pond owners have been identified as aquatic invasive species vectors within the Laurentian Great Lakes region. The trademarked U.S. Fish and Wildlife Service Habitattitude campaign was developed in 2004 to encourage self-regulation by these groups, but little is known about its effects. We surveyed organisms-in-trade hobbyists in the eight Great Lakes states (Illinois, Indiana, Michigan, Minnesota, New York, Ohio, Pennsylvania, and Wisconsin, USA) to assess their recognition of the Habitattitude campaign and their compliance with the campaign's recommended behaviors for organism purchase and disposal. Awareness of the Habitattitude campaign was low, but hobbyists that identified as both water gardeners and aquarium hobbyists were more aware of the campaign than individuals who participated in one of those hobbies. Engaged hobbyists (high aquatic invasive species awareness, concern, and knowledge) were significantly more likely than passive hobbyists (low aquatic invasive species awareness, concern, and knowledge) to make decisions about disposal of live organisms with the intention of preventing aquatic invasive species spread, were more likely to contact other hobbyists for disposal and handling advice, and were less likely to contact professionals, such as retailers. On the basis of our results, we suggest that compliance with recommended behaviors may be increased by fostering hobbyist networks; creating materials that both explain tangible, negative environmental impacts and list specific prevention behaviors; and disseminating these materials through trusted information sources and venues.

  18. Analytical fractionation of aquatic humic substances and their metal species by means of multistage ultrafiltration.

    PubMed

    Aster, B; Burba, P; Broekaert, J A

    1996-03-01

    The molecular-size fractionation of aquatic humic substances (HS) and their metal species by means of a novel sequential-stage ultrafiltration (UF) device equipped with five appropriate ultramembranes (1, 5, 10, 50 and 100 kD) is described. First of all, the concentration dynamics of macromolecules, particulary HS, during five-stage UF and its subsequent washing step has been modelled. Based on these results, the fractionation of aquatic HS (from ground and bog water) by means of multistage UF has been optimized for an analytical scale (10 ml sample, 1 mg/ml HS, 10 ml washing solution, pH 6.0). The molecular size-distribution of selected aquatic HS (BOC 1/2 from the "DFG-Versuchsfeld Bocholt", VM 5 from "Venner Moor", Germany) studied by five-stage UF exhibited strong systematic influences of the procedure used for their isolation. The molecular-size distribution of HS obtained by on-line UF and gel permeation chromatography (GPC) showed a satisfactory agreement in the range 1-50 kD. Moreover, when interrupting multistage UF for > 48 h a slow transformation in the HS samples has been found as gradually additional HS fractions of < 1 kD have been formed. Besides unloaded HS molecules, the molecular-size distribution of freshly formed metal species of HS (1.0 mg metal/g HS of Al(III), Cd(II), Cu(II), Fe(III), Mn(II), Ni(II), Pb(II), Zn(II), each) has been characterized by multistage UF as a function of pH-value, degree of loading and complexation time. Metal determinations as carried out by flame AAS, showed that considerable metal fractions in HS especially are present in molecules > 50 kD, which seemed to be rather acid-inert. With complexation times of < 2 days a transient shift of the molecular size distribution of both HS and their metal species (e.g., Al(III), Fe(III) to higher values (> 10 kD) has been found.

  19. Acute toxicity of zinc to several aquatic species native to the Rocky Mountains.

    PubMed

    Brinkman, Stephen F; Johnston, Walter D

    2012-02-01

    National water-quality criteria for the protection of aquatic life are based on toxicity tests, often using organisms that are easy to culture in the laboratory. Species native to the Rocky Mountains are poorly represented in data sets used to derive national water-quality criteria. To provide additional data on the toxicity of zinc, several laboratory acute-toxicity tests were conducted with a diverse assortment of fish, benthic invertebrates, and an amphibian native to the Rocky Mountains. Tests with fish were conducted using three subspecies of cutthroat trout (Colorado River cutthroat trout Oncorhynchus clarkii pleuriticus, greenback cutthroat trout O. clarkii stomias, and Rio Grande cutthroat trout O. clarkii virginalis), mountain whitefish (Prosopium williamsoni), mottled sculpin (Cottus bairdi), longnose dace (Rhinichthys cataractae), and flathead chub (Platygobio gracilis). Aquatic invertebrate tests were conducted with mayflies (Baetis tricaudatus, Drunella doddsi, Cinygmula sp. and Ephemerella sp.), a stonefly (Chloroperlidae), and a caddis fly (Lepidostoma sp.). The amphibian test was conducted with tadpoles of the boreal toad (Bufo boreas). Median lethal concentrations (LC(50)s) ranged more than three orders of magnitude from 166 μg/L for Rio Grande cutthroat trout to >67,000 μg/L for several benthic invertebrates. Of the organisms tested, vertebrates were the most sensitive, and benthic invertebrates were the most tolerant. PMID:21811884

  20. Transcriptome sequencing of three Ranunculus species (Ranunculaceae) reveals candidate genes in adaptation from terrestrial to aquatic habitats

    PubMed Central

    Chen, Ling-Yun; Zhao, Shu-Ying; Wang, Qing-Feng; Moody, Michael L.

    2015-01-01

    Adaptation to aquatic habitats is a formidable challenge for terrestrial angiosperms that has long intrigued scientists. As part of a suite of work to explore the molecular mechanism of adaptation to aquatic habitats, we here sequenced the transcriptome of the submerged aquatic plant Ranunculus bungei, and two terrestrial relatives R. cantoniensis and R. brotherusii, followed by comparative evolutionary analyses to determine candidate genes for adaption to aquatic habitats. We obtained 126,037, 140,218 and 114,753 contigs for R. bungei, R. cantoniensis and R. brotherusii respectively. Bidirectional Best Hit method and OrthoMCL method identified 11,362 and 8,174 1:1:1 orthologous genes (one ortholog is represented in each of the three species) respectively. Non-synonymous/synonymous (dN/dS) analyses were performed with a maximum likelihood method and an approximate method for the three species-pairs. In total, 14 genes of R. bungei potentially involved in the adaptive transition from terrestrial to aquatic habitats were identified. Some of the homologs to these genes in model plants are involved in vacuole protein formation, regulating ‘water transport process’ and ‘microtubule cytoskeleton organization’. Our study opens the door to understand the molecular mechanism of plant adaptation from terrestrial to aquatic habitats. PMID:25993393

  1. Biochemical effects of acetaminophen in aquatic species: edible clams Venerupis decussata and Venerupis philippinarum.

    PubMed

    Antunes, S C; Freitas, Rosa; Figueira, E; Gonçalves, Fernando; Nunes, Bruno

    2013-09-01

    Acetaminophen (paracetamol) is one of the most used pharmaceutical drugs, due to its antipyretic and analgesic properties that turn it into a primary choice in varied pathologies and conditions. However, and despite its massive use, acetaminophen is not exempt of adverse effects, especially when administered in over dosage, which are related to the formation of toxic metabolites by oxidative pathways. It is thus possible to observe that toxicity caused by acetaminophen is usually mediated by reactive oxygen species and can result in multiple effects, ranging from protein denaturation to lipid peroxidation and DNA damage. The occurrence of acetaminophen has been reported in the aquatic environment, being important to address the potential exertion of toxic effects on nontarget environmentally exposed organisms. The present study intended to characterize the effects of acute acetaminophen exposure on physiological traits (antioxidant defense, oxidative damage) of two species of bivalves, namely, the edible clams Venerupis decussata and Venerupis philippinarum. Results showed a significant increase in all oxidative stress biomarkers, evidencing the bioactivation of acetaminophen into a deleterious prooxidant, triggering the onset of deleterious effects. Furthermore, strong interspecific differences were observed among responses of the two tested species, which was a major issue due to intrinsic ecological implications when one considers that both species share the same habitat.

  2. Occurrence and Diversity of Clinically Important Vibrio Species in the Aquatic Environment of Georgia.

    PubMed

    Kokashvili, Tamar; Whitehouse, Chris A; Tskhvediani, Ana; Grim, Christopher J; Elbakidze, Tinatin; Mitaishvili, Nino; Janelidze, Nino; Jaiani, Ekaterine; Haley, Bradd J; Lashkhi, Nino; Huq, Anwar; Colwell, Rita R; Tediashvili, Marina

    2015-01-01

    Among the more than 70 different Vibrio species inhabiting marine, estuarine, and freshwater ecosystems, 12 are recognized as human pathogens. The warm subtropical climate of the Black Sea coastal area and inland regions of Georgia likely provides a favorable environment for various Vibrio species. From 2006 to 2009, the abundance, ecology, and diversity of clinically important Vibrio species were studied in different locations in Georgia and across seasons. Over a 33-month period, 1,595 presumptive Vibrio isolates were collected from the Black Sea (n = 657) and freshwater lakes around Tbilisi (n = 938). Screening of a subset of 440 concentrated and enriched water samples by PCR-electrospray ionization/mass spectrometry (PCR-ESI/MS) detected the presence of DNA from eight clinically important Vibrio species: V. cholerae, V. parahaemolyticus, V. vulnificus, V. mimicus, V. alginolyticus, V. harveyi, V. metschnikovii, and V. cincinnatiensis. Almost 90% of PCR/ESI-MS samples positive for Vibrio species were collected from June through November. Three important human-pathogenic Vibrio species (V. cholerae, V. parahaemolyticus, and V. vulnificus) were detected in 62.8, 37.8, and 21.4% of samples testing positive for Vibrios, respectively. The results of these activities suggest that natural reservoirs for human-pathogenic Vibrios exist in Georgian aquatic environments. Water temperature at all sampling sites was positively correlated with the abundance of clinically important Vibrio spp. (except V. metschnikovii), and salinity was correlated with species composition at particular Black Sea sites as well as inland reservoirs. PMID:26528464

  3. Occurrence and Diversity of Clinically Important Vibrio Species in the Aquatic Environment of Georgia.

    PubMed

    Kokashvili, Tamar; Whitehouse, Chris A; Tskhvediani, Ana; Grim, Christopher J; Elbakidze, Tinatin; Mitaishvili, Nino; Janelidze, Nino; Jaiani, Ekaterine; Haley, Bradd J; Lashkhi, Nino; Huq, Anwar; Colwell, Rita R; Tediashvili, Marina

    2015-01-01

    Among the more than 70 different Vibrio species inhabiting marine, estuarine, and freshwater ecosystems, 12 are recognized as human pathogens. The warm subtropical climate of the Black Sea coastal area and inland regions of Georgia likely provides a favorable environment for various Vibrio species. From 2006 to 2009, the abundance, ecology, and diversity of clinically important Vibrio species were studied in different locations in Georgia and across seasons. Over a 33-month period, 1,595 presumptive Vibrio isolates were collected from the Black Sea (n = 657) and freshwater lakes around Tbilisi (n = 938). Screening of a subset of 440 concentrated and enriched water samples by PCR-electrospray ionization/mass spectrometry (PCR-ESI/MS) detected the presence of DNA from eight clinically important Vibrio species: V. cholerae, V. parahaemolyticus, V. vulnificus, V. mimicus, V. alginolyticus, V. harveyi, V. metschnikovii, and V. cincinnatiensis. Almost 90% of PCR/ESI-MS samples positive for Vibrio species were collected from June through November. Three important human-pathogenic Vibrio species (V. cholerae, V. parahaemolyticus, and V. vulnificus) were detected in 62.8, 37.8, and 21.4% of samples testing positive for Vibrios, respectively. The results of these activities suggest that natural reservoirs for human-pathogenic Vibrios exist in Georgian aquatic environments. Water temperature at all sampling sites was positively correlated with the abundance of clinically important Vibrio spp. (except V. metschnikovii), and salinity was correlated with species composition at particular Black Sea sites as well as inland reservoirs.

  4. Divergence in threat sensitivity among aquatic larvae of cryptic mosquito species.

    PubMed

    Roux, Olivier; Diabaté, Abdoulaye; Simard, Frédéric

    2014-05-01

    Predation is a major evolutionary force driving speciation. The threat-sensitive response hypothesis predicts that prey adjust and balance the time spent on a costly antipredator response with other activities that enhance their fitness. Thus, prey able to develop an antipredator response proportional to risk intensity should have a selective advantage. Knowledge on how evolution has shaped threat sensitivity among closely related species exposed to different predation pressures is scarce, prompting investigations to better predict and explain its effect on communities. We explored and compared the antipredator response of aquatic mosquito larvae in three sibling species of the Anopheles gambiae complex, with contrasting larval biologies in Burkina Faso. Anopheles arabiensis and An. gambiae sensu stricto breed in temporary water collections where predator densities are low, whereas Anopheles coluzzii is able to thrive in permanent pools where the predation pressure is much higher. We hypothesized that the increase and decline of behavioural antipredator responses might differ between the three species over time. To test this hypothesis, progenies of field-collected mosquitoes were experimentally exposed to a range of soluble predation cues and their response was monitored for up to 48 h. The three species were all threat sensitive but their reaction norms differed. For the range of concentrations tested, An. coluzzii larvae gradually increased in antipredator response, whereas An. gambiae larvae readily displayed antipredator behaviour at low concentrations leading to a saturation of the response for high cue concentrations. An. arabiensis displayed a narrower reaction norm with low response intensity. Larval instars did not differ in their threat sensitivity. The antipredator behaviour of the three species waned after about 1 h of exposure. Early instars tended to express antipredation behaviour for longer than did older instars. This study provides information on

  5. Genomics of Extinct and Endangered Species (2011 JGI User Meeting)

    ScienceCinema

    Shuster, Stephen [Penn State University

    2016-07-12

    The U.S. Department of Energy Joint Genome Institute (JGI) invited scientists interested in the application of genomics to bioenergy and environmental issues, as well as all current and prospective users and collaborators, to attend the annual DOE JGI Genomics of Energy & Environment Meeting held March 22-24, 2011 in Walnut Creek, Calif. The emphasis of this meeting was on the genomics of renewable energy strategies, carbon cycling, environmental gene discovery, and engineering of fuel-producing organisms. The meeting features presentations by leading scientists advancing these topics. Stephen Shuster of Penn State University gives a presentation on "Genomics of Extinct and Endangered Species" at the 6th annual Genomics of Energy & Environment Meeting on March 23, 2011

  6. Genomics of Extinct and Endangered Species (2011 JGI User Meeting)

    SciTech Connect

    Shuster, Stephen

    2011-03-23

    The U.S. Department of Energy Joint Genome Institute (JGI) invited scientists interested in the application of genomics to bioenergy and environmental issues, as well as all current and prospective users and collaborators, to attend the annual DOE JGI Genomics of Energy & Environment Meeting held March 22-24, 2011 in Walnut Creek, Calif. The emphasis of this meeting was on the genomics of renewable energy strategies, carbon cycling, environmental gene discovery, and engineering of fuel-producing organisms. The meeting features presentations by leading scientists advancing these topics. Stephen Shuster of Penn State University gives a presentation on "Genomics of Extinct and Endangered Species" at the 6th annual Genomics of Energy & Environment Meeting on March 23, 2011

  7. Diversity of Aquatic Pseudomonas Species and Their Activity against the Fish Pathogenic Oomycete Saprolegnia

    PubMed Central

    Liu, Yiying; Rzeszutek, Elzbieta; van der Voort, Menno; Wu, Cheng-Hsuan; Thoen, Even; Skaar, Ida; Bulone, Vincent; Dorrestein, Pieter C.; Raaijmakers, Jos M.; de Bruijn, Irene

    2015-01-01

    Emerging fungal and oomycete pathogens are increasingly threatening animals and plants globally. Amongst oomycetes, Saprolegnia species adversely affect wild and cultivated populations of amphibians and fish, leading to substantial reductions in biodiversity and food productivity. With the ban of several chemical control measures, new sustainable methods are needed to mitigate Saprolegnia infections in aquaculture. Here, PhyloChip-based community analyses showed that the Pseudomonadales, particularly Pseudomonas species, represent one of the largest bacterial orders associated with salmon eggs from a commercial hatchery. Among the Pseudomonas species isolated from salmon eggs, significantly more biosurfactant producers were retrieved from healthy salmon eggs than from Saprolegnia-infected eggs. Subsequent in vivo activity bioassays showed that Pseudomonas isolate H6 significantly reduced salmon egg mortality caused by Saprolegnia diclina. Live colony mass spectrometry showed that strain H6 produces a viscosin-like lipopeptide surfactant. This biosurfactant inhibited growth of Saprolegnia in vitro, but no significant protection of salmon eggs against Saprolegniosis was observed. These results indicate that live inocula of aquatic Pseudomonas strains, instead of their bioactive compound, can provide new (micro)biological and sustainable means to mitigate oomycete diseases in aquaculture. PMID:26317985

  8. Diversity of Aquatic Pseudomonas Species and Their Activity against the Fish Pathogenic Oomycete Saprolegnia.

    PubMed

    Liu, Yiying; Rzeszutek, Elzbieta; van der Voort, Menno; Wu, Cheng-Hsuan; Thoen, Even; Skaar, Ida; Bulone, Vincent; Dorrestein, Pieter C; Raaijmakers, Jos M; de Bruijn, Irene

    2015-01-01

    Emerging fungal and oomycete pathogens are increasingly threatening animals and plants globally. Amongst oomycetes, Saprolegnia species adversely affect wild and cultivated populations of amphibians and fish, leading to substantial reductions in biodiversity and food productivity. With the ban of several chemical control measures, new sustainable methods are needed to mitigate Saprolegnia infections in aquaculture. Here, PhyloChip-based community analyses showed that the Pseudomonadales, particularly Pseudomonas species, represent one of the largest bacterial orders associated with salmon eggs from a commercial hatchery. Among the Pseudomonas species isolated from salmon eggs, significantly more biosurfactant producers were retrieved from healthy salmon eggs than from Saprolegnia-infected eggs. Subsequent in vivo activity bioassays showed that Pseudomonas isolate H6 significantly reduced salmon egg mortality caused by Saprolegnia diclina. Live colony mass spectrometry showed that strain H6 produces a viscosin-like lipopeptide surfactant. This biosurfactant inhibited growth of Saprolegnia in vitro, but no significant protection of salmon eggs against Saprolegniosis was observed. These results indicate that live inocula of aquatic Pseudomonas strains, instead of their bioactive compound, can provide new (micro)biological and sustainable means to mitigate oomycete diseases in aquaculture. PMID:26317985

  9. Variation in sensitivity of aquatic species to toxicants: Practical consequences for effect assessment of chemical substances

    SciTech Connect

    Vaal, M.A.; Van Leeuwen, C.J.; Hoekstra, J.A.; Hermens, J.L.M.

    2000-04-01

    This study addresses the relation between the sensitivity of aquatic species and mode of action of different classes or organic chemicals. The authors analyzed large data sets of ecotoxicological information to reveal the interspecies variation in sensitivity, to relate this variation to the compounds' mode of action, and to explain the observed patterns using general biological information. Here the authors present a general framework and recommendations for risk assessment procedures. The authors recommend the use of toxicologically based classification schemes at an early stage of the risk assessment procedure. Screening programs are most efficiently run when only one species per compound is tested to prioritize substances. The toxicity of compounds belonging to the class of nonpolar narcotics is highly predictable and shows little interspecies variation. For these compounds quantitative structure-activity relationships (WSARs) can be used to estimate effect levels. Most effort should be put into testing reactive compounds and compounds with a specific mode of action as toxicity to some species can be 10{sup 5}--10{sup 6} times higher compared with less sensitive species. The use of assessment factors in effect assessment procedures may lead to an underestimation of effects on the more sensitive species. For many priority pollutants there is little information on their ecotoxicity. Predictive techniques are needed to compensate for this lack of data. Knowledge of the relation between modes of action of compounds and interspecies variation in sensitivity should be integrated in risk assessment procedures in order to make more efficient use of the limited financial resources available.

  10. Responses of aquatic insects to Cu and Zn in stream microcosms: understanding differences between single species tests and field responses.

    PubMed

    Clements, William H; Cadmus, Pete; Brinkman, Stephen F

    2013-07-01

    Field surveys of metal-contaminated streams suggest that some aquatic insects, particularly mayflies (Ephemeroptera) and stoneflies (Plecoptera), are highly sensitive to metals. However, results of single species toxicity tests indicate these organisms are quite tolerant, with LC50 values often several orders of magnitude greater than those obtained using standard test organisms (e.g., cladocerans and fathead minnows). Reconciling these differences is a critical research need, particularly since water quality criteria for metals are based primarily on results of single species toxicity tests. In this research we provide evidence based on community-level microcosm experiments to support the hypothesis that some aquatic insects are highly sensitive to metals. We present results of three experiments that quantified effects of Cu and Zn, alone and in combination, on stream insect communities. EC50 values, defined as the metal concentration that reduced abundance of aquatic insects by 50%, were several orders of magnitude lower than previously published values obtained from single species tests. We hypothesize that the short duration of laboratory toxicity tests and the failure to evaluate effects of metals on sensitive early life stages are the primary factors responsible for unrealistically high LC50 values in the literature. We also observed that Cu alone was significantly more toxic to aquatic insects than the combination of Cu and Zn, despite the fact that exposure concentrations represented theoretically similar toxicity levels. Our results suggest that water quality criteria for Zn were protective of most aquatic insects, whereas Cu was highly toxic to some species at concentrations near water quality criteria. Because of the functional significance of aquatic insects in stream ecosystems and their well-established importance as indicators of water quality, reconciling differences between field and laboratory responses and understanding the mechanisms responsible

  11. Responses of aquatic insects to Cu and Zn in stream microcosms: understanding differences between single species tests and field responses.

    PubMed

    Clements, William H; Cadmus, Pete; Brinkman, Stephen F

    2013-07-01

    Field surveys of metal-contaminated streams suggest that some aquatic insects, particularly mayflies (Ephemeroptera) and stoneflies (Plecoptera), are highly sensitive to metals. However, results of single species toxicity tests indicate these organisms are quite tolerant, with LC50 values often several orders of magnitude greater than those obtained using standard test organisms (e.g., cladocerans and fathead minnows). Reconciling these differences is a critical research need, particularly since water quality criteria for metals are based primarily on results of single species toxicity tests. In this research we provide evidence based on community-level microcosm experiments to support the hypothesis that some aquatic insects are highly sensitive to metals. We present results of three experiments that quantified effects of Cu and Zn, alone and in combination, on stream insect communities. EC50 values, defined as the metal concentration that reduced abundance of aquatic insects by 50%, were several orders of magnitude lower than previously published values obtained from single species tests. We hypothesize that the short duration of laboratory toxicity tests and the failure to evaluate effects of metals on sensitive early life stages are the primary factors responsible for unrealistically high LC50 values in the literature. We also observed that Cu alone was significantly more toxic to aquatic insects than the combination of Cu and Zn, despite the fact that exposure concentrations represented theoretically similar toxicity levels. Our results suggest that water quality criteria for Zn were protective of most aquatic insects, whereas Cu was highly toxic to some species at concentrations near water quality criteria. Because of the functional significance of aquatic insects in stream ecosystems and their well-established importance as indicators of water quality, reconciling differences between field and laboratory responses and understanding the mechanisms responsible

  12. Protecting sediment-sensitive aquatic species inmountain streams through the application of biologically based streambed sediment criteria

    EPA Science Inventory

    We evaluated several lines of evidence to identify bedded fine sediment levels that should protect and maintain self-sustaining populations of native sediment-sensitive aquatic species in the western US. To identify these potential criterion values for streambed sediments ≤0.06 ...

  13. A decade of aquatic invasive species (AIS) early detection method development in the St. Louis River estuary

    EPA Science Inventory

    As an invasion prone location, the St. Louis River Estuary (SLRE) has been a case study for ongoing research to develop the framework for a practical Great Lakes monitoring network for early detection of aquatic invasive species (AIS). Early detection, however, necessitates findi...

  14. Plasticizer endocrine disruption: Highlighting developmental and reproductive effects in mammals and non-mammalian aquatic species.

    PubMed

    Mathieu-Denoncourt, Justine; Wallace, Sarah J; de Solla, Shane R; Langlois, Valerie S

    2015-08-01

    Due to their versatility, robustness, and low production costs, plastics are used in a wide variety of applications. Plasticizers are mixed with polymers to increase flexibility of plastics. However, plasticizers are not covalently bound to plastics, and thus leach from products into the environment. Several studies have reported that two common plasticizers, bisphenol A (BPA) and phthalates, induce adverse health effects in vertebrates; however few studies have addressed their toxicity to non-mammalian species. The aim of this review is to compare the effects of plasticizers in animals, with a focus on aquatic species. In summary, we identified three main chains of events that occur in animals exposed to BPA and phthalates. Firstly, plasticizers affect development by altering both the thyroid hormone and growth hormone axes. Secondly, these chemicals interfere with reproduction by decreasing cholesterol transport through the mitochondrial membrane, leading to reduced steroidogenesis. Lastly, exposure to plasticizers leads to the activation of peroxisome proliferator-activated receptors, the increase of fatty acid oxidation, and the reduction in the ability to cope with the augmented oxidative stress leading to reproductive organ malformations, reproductive defects, and decreased fertility.

  15. Aquatic pollution may favor the success of the invasive species A. franciscana.

    PubMed

    Varó, I; Redón, S; Garcia-Roger, E M; Amat, F; Guinot, D; Serrano, R; Navarro, J C

    2015-04-01

    The genus Artemia consists of several bisexual and parthenogenetic sibling species. One of them, A. franciscana, originally restricted to the New World, becomes invasive when introduced into ecosystems out of its natural range of distribution. Invasiveness is anthropically favored by the use of cryptobiotic eggs in the aquaculture and pet trade. The mechanisms of out-competition of the autochthonous Artemia by the invader are still poorly understood. Ecological fitness may play a pivotal role, but other underlying biotic and abiotic factors may contribute. Since the presence of toxicants in hypersaline aquatic ecosystems has been documented, our aim here is to study the potential role of an organophosphate pesticide, chlorpyrifos, in a congeneric mechanism of competition between the bisexual A. franciscana (AF), and one of the Old World parthenogenetic siblings, A. parthenogenetica (PD). For this purpose we carried out life table experiments with both species, under different concentrations of the toxicant (0.1, 1 and 5μg/l), and analyzed the cholinesterase inhibition at different developmental stages. The results evidence that both, AF and PD, showed an elevated tolerance to high ranges of chlorpyrifos, but AF survived better and its fecundity was less affected by the exposure to the pesticide than that of PD. The higher fecundity of AF is a selective advantage in colonization processes leading to its establishment as NIS. Besides, under the potential selective pressure of abiotic factors, such as the presence of toxicants, its higher resistance in terms of survival and biological fitness also indicates out-competitive advantages.

  16. Assessment of environmental DNA for detecting presence of imperiled aquatic amphibian species in isolated wetlands

    USGS Publications Warehouse

    Mckee, Anna; Calhoun, Daniel L.; Barichivich, William J.; Spear, Stephen F.; Goldberg, Caren S.; Glenn, Travis C

    2015-01-01

    Environmental DNA (eDNA) is an emerging tool that allows low-impact sampling for aquatic species by isolating DNA from water samples and screening for DNA sequences specific to species of interest. However, researchers have not tested this method in naturally acidic wetlands that provide breeding habitat for a number of imperiled species, including the frosted salamander (Ambystoma cingulatum), reticulated flatwoods salamanders (Ambystoma bishopi), striped newt (Notophthalmus perstriatus), and gopher frog (Lithobates capito). Our objectives for this study were to develop and optimize eDNA survey protocols and assays to complement and enhance capture-based survey methods for these amphibian species. We collected three or more water samples, dipnetted or trapped larval and adult amphibians, and conducted visual encounter surveys for egg masses for target species at 40 sites on 12 different longleaf pine (Pinus palustris) tracts. We used quantitative PCRs to screen eDNA from each site for target species presence. We detected flatwoods salamanders at three sites with eDNA but did not detect them during physical surveys. Based on the sample location we assumed these eDNA detections to indicate the presence of frosted flatwoods salamanders. We did not detect reticulated flatwoods salamanders. We detected striped newts with physical and eDNA surveys at two wetlands. We detected gopher frogs at 12 sites total, three with eDNA alone, two with physical surveys alone, and seven with physical and eDNA surveys. We detected our target species with eDNA at 9 of 11 sites where they were present as indicated from traditional surveys and at six sites where they were not detected with traditional surveys. It was, however, critical to use at least three water samples per site for eDNA. Our results demonstrate eDNA surveys can be a useful complement to traditional survey methods for detecting imperiled pond-breeding amphibians. Environmental DNA may be particularly useful in situations

  17. Hypoxanthine-guanine phosphoribosyltransferase and inosine 5'-monophosphate dehydrogenase activities in three mammalian species: aquatic (Mirounga angustirostris), semi-aquatic (Lontra longicaudis annectens) and terrestrial (Sus scrofa).

    PubMed

    Barjau Pérez-Milicua, Myrna; Zenteno-Savín, Tania; Crocker, Daniel E; Gallo-Reynoso, Juan P

    2015-01-01

    Aquatic and semiaquatic mammals have the capacity of breath hold (apnea) diving. Northern elephant seals (Mirounga angustirostris) have the ability to perform deep and long duration dives; during a routine dive, adults can hold their breath for 25 min. Neotropical river otters (Lontra longicaudis annectens) can hold their breath for about 30 s. Such periods of apnea may result in reduced oxygen concentration (hypoxia) and reduced blood supply (ischemia) to tissues. Production of adenosine 5'-triphosphate (ATP) requires oxygen, and most mammalian species, like the domestic pig (Sus scrofa), are not adapted to tolerate hypoxia and ischemia, conditions that result in ATP degradation. The objective of this study was to explore the differences in purine synthesis and recycling in erythrocytes and plasma of three mammalian species adapted to different environments: aquatic (northern elephant seal) (n = 11), semiaquatic (neotropical river otter) (n = 4), and terrestrial (domestic pig) (n = 11). Enzymatic activity of hypoxanthine-guanine phosphoribosyltransferase (HGPRT) was determined by spectrophotometry, and activity of inosine 5'-monophosphate dehydrogenase (IMPDH) and the concentration of hypoxanthine (HX), inosine 5'-monophosphate (IMP), adenosine 5'-monophosphate (AMP), adenosine 5'-diphosphate (ADP), ATP, guanosine 5'-diphosphate (GDP), guanosine 5'-triphosphate (GTP), and xanthosine 5'-monophosphate (XMP) were determined by high-performance liquid chromatography (HPLC). The activities of HGPRT and IMPDH and the concentration of HX, IMP, AMP, ADP, ATP, GTP, and XMP in erythrocytes of domestic pigs were higher than in erythrocytes of northern elephant seals and river otters. These results suggest that under basal conditions (no diving, sleep apnea or exercise), aquatic, and semiaquatic mammals have less purine mobilization than their terrestrial counterparts.

  18. Hypoxanthine-guanine phosphoribosyltransferase and inosine 5'-monophosphate dehydrogenase activities in three mammalian species: aquatic (Mirounga angustirostris), semi-aquatic (Lontra longicaudis annectens) and terrestrial (Sus scrofa).

    PubMed

    Barjau Pérez-Milicua, Myrna; Zenteno-Savín, Tania; Crocker, Daniel E; Gallo-Reynoso, Juan P

    2015-01-01

    Aquatic and semiaquatic mammals have the capacity of breath hold (apnea) diving. Northern elephant seals (Mirounga angustirostris) have the ability to perform deep and long duration dives; during a routine dive, adults can hold their breath for 25 min. Neotropical river otters (Lontra longicaudis annectens) can hold their breath for about 30 s. Such periods of apnea may result in reduced oxygen concentration (hypoxia) and reduced blood supply (ischemia) to tissues. Production of adenosine 5'-triphosphate (ATP) requires oxygen, and most mammalian species, like the domestic pig (Sus scrofa), are not adapted to tolerate hypoxia and ischemia, conditions that result in ATP degradation. The objective of this study was to explore the differences in purine synthesis and recycling in erythrocytes and plasma of three mammalian species adapted to different environments: aquatic (northern elephant seal) (n = 11), semiaquatic (neotropical river otter) (n = 4), and terrestrial (domestic pig) (n = 11). Enzymatic activity of hypoxanthine-guanine phosphoribosyltransferase (HGPRT) was determined by spectrophotometry, and activity of inosine 5'-monophosphate dehydrogenase (IMPDH) and the concentration of hypoxanthine (HX), inosine 5'-monophosphate (IMP), adenosine 5'-monophosphate (AMP), adenosine 5'-diphosphate (ADP), ATP, guanosine 5'-diphosphate (GDP), guanosine 5'-triphosphate (GTP), and xanthosine 5'-monophosphate (XMP) were determined by high-performance liquid chromatography (HPLC). The activities of HGPRT and IMPDH and the concentration of HX, IMP, AMP, ADP, ATP, GTP, and XMP in erythrocytes of domestic pigs were higher than in erythrocytes of northern elephant seals and river otters. These results suggest that under basal conditions (no diving, sleep apnea or exercise), aquatic, and semiaquatic mammals have less purine mobilization than their terrestrial counterparts. PMID:26283971

  19. Clonal Plasticity of Aquatic Plant Species Submitted to Mechanical Stress: Escape versus Resistance Strategy

    PubMed Central

    Puijalon, Sara; Bouma, Tjeerd J.; Van Groenendael, Jan; Bornette, Gudrun

    2008-01-01

    Background and Aims The plastic alterations of clonal architecture are likely to have functional consequences, as they affect the spatial distribution of ramets over patchy environments. However, little is known about the effect of mechanical stresses on the clonal growth. The aim of the present study was to investigate the clonal plasticity induced by mechanical stress consisting of continuous water current encountered by aquatic plants. More particularly, the aim was to test the capacity of the plants to escape this stress through clonal plastic responses. Methods The transplantation of ramets of the same clone in two contrasting flow velocity conditions was carried out for two species (Potamogeton coloratus and Mentha aquatica) which have contrasting clonal growth forms. Relative allocation to clonal growth, to creeping stems in the clonal biomass, number and total length of creeping stems, spacer length and main creeping stem direction were measured. Key Results For P. coloratus, plants exposed to water current displayed increased total length of creeping stems, increased relative allocation to creeping stems within the clonal dry mass and increased spacer length. For M. aquatica, plants exposed to current displayed increased number and total length of creeping stems. Exposure to current induced for both species a significant increase of the proportion of creeping stems in the downstream direction to the detriment of creeping stems perpendicular to flow. Conclusions This study demonstrates that mechanical stress from current flow induced plastic variation in clonal traits for both species. The responses of P. coloratus could lead to an escape strategy, with low benefits with respect to sheltering and anchorage. The responses of M. aquatica that may result in a denser canopy and enhancement of anchorage efficiency could lead to a resistance strategy. PMID:18854376

  20. Convergent evolution of aquatic foraging in a new genus and species (Rodentia: Muridae) from Sulawesi Island, Indonesia.

    PubMed

    Rowe, Kevin C; Achmadi, Anang S; Esselstyn, Jacob A

    2014-01-01

    The island of Sulawesi, in Indonesia, lies at the crossroads of the Indo-Australian Archipelago and has remained isolated from the Asian (Sunda) and Australian (Sahul) continental shelves for at least the last 10 million years. Of the 50 native species of rodents on Sulawesi, all are endemic and represent the evolution of a variety of ecological and morphological forms within the Muridae and Sciuridae. Carnivorous rodents have evolved, perhaps independently, in Muridae from the Philippines, Sulawesi, and Sahul, but semi-aquatic murids are only known from Sahul. Here we describe a new genus and species of insectivorous water rat from Sulawesi. Phylogenetic analyses demonstrate that it is related to the shrew rats of Sulawesi and represents an origin of aquatic carnivory that is independent from the evolution of water rats on Sahul. Many areas of Sulawesi have not been surveyed systematically and current lists of mammal species are likely to dramatically underestimate actual diversity. PMID:24943633

  1. Tectonics, climate, and the rise and demise of continental aquatic species richness hotspots

    PubMed Central

    Neubauer, Thomas A.; Harzhauser, Mathias; Georgopoulou, Elisavet; Kroh, Andreas; Mandic, Oleg

    2015-01-01

    Continental aquatic species richness hotspots are unevenly distributed across the planet. In present-day Europe, only two centers of biodiversity exist (Lake Ohrid on the Balkans and the Caspian Sea). During the Neogene, a wide variety of hotspots developed in a series of long-lived lakes. The mechanisms underlying the presence of richness hotspots in different geological periods have not been properly examined thus far. Based on Miocene to Recent gastropod distributions, we show that the existence and evolution of such hotspots in inland-water systems are tightly linked to the geodynamic history of the European continent. Both past and present hotspots are related to the formation and persistence of long-lived lake systems in geological basins or to isolation of existing inland basins and embayments from the marine realm. The faunal evolution within hotspots highly depends on warm climates and surface area. During the Quaternary icehouse climate and extensive glaciations, limnic biodiversity sustained a severe decline across the continent and most former hotspots disappeared. The Recent gastropod distribution is mainly a geologically young pattern formed after the Last Glacial Maximum (19 ky) and subsequent formation of postglacial lakes. The major hotspots today are related to long-lived lakes in preglacially formed, permanently subsiding geological basins. PMID:26305934

  2. Interaction of arsenic species with tropical river aquatic humic substances enriched with aluminum and iron.

    PubMed

    de Oliveira, Lilian Karla; Melo, Camila de Almeida; Fraceto, Leonardo Fernandes; Friese, Kurt; Rosa, André Henrique

    2016-04-01

    The mobility and bioavailability of arsenic (As) are strongly controlled by adsorption/precipitation processes involving metal oxides. However, the organic matter present in the environment, in combination with these oxides, can also play an important role in the cycle of arsenic. This work concerns the interaction between As and two samples of aquatic humic substances (AHS) from tropical rivers. The AHS were extracted as proposed by IHSS, and were characterized by (13)C NMR. The experiments were conducted with the AHS in natura and enriched with metal cations, with different concentrations of As, and complexation capacity was evaluated at three different pH levels (5.0, 7.0, and 9.0). The AHS samples showed similar chemical compositions. The results suggested that there was no interaction between As(III) and AHS in natura or enriched with Al. Low concentrations of As(V) were bound to AHS in natura. For As(III), the complexation capacity of the AHS enriched with Fe was approximately 48 μmol per g of C, while the values for As(V) were in the range 69-80 μmol per grams of C. Fluorescence spectra showed that changes in Eh affected the complexation reactions of As(V) species with AHS. PMID:26606934

  3. Predicting the aquatic risk of realistic pesticide mixtures to species assemblages in Portuguese river basins.

    PubMed

    Silva, Emília; Daam, Michiel A; Cerejeira, Maria José

    2015-05-01

    Although pesticide regulatory tools are mainly based on individual substances, aquatic ecosystems are usually exposed to multiple pesticides from their use on the variety of crops within the catchment of a river. This study estimated the impact of measured pesticide mixtures in surface waters from 2002 and 2008 within three important Portuguese river basins ('Mondego', 'Sado' and 'Tejo') on primary producers, arthropods and fish by toxic pressure calculation. Species sensitivity distributions (SSDs), in combination with mixture toxicity models, were applied. Considering the differences in the responses of the taxonomic groups as well as in the pesticide exposures that these organisms experience, variable acute multi-substance potentially affected fractions (msPAFs) were obtained. The median msPAF for primary producers and arthropods in surface waters of all river basins exceeded 5%, the cut-off value used in the prospective SSD approach for deriving individual environmental quality standards. A ranking procedure identified various photosystem II inhibiting herbicides, with oxadiazon having the relatively largest toxic effects on primary producers, while the organophosphorus insecticides, chlorfenvinphos and chlorpyrifos, and the organochloride endosulfan had the largest effects on arthropods and fish, respectively. These results ensure compliance with European legislation with regard to ecological risk assessment and management of pesticides in surface waters. PMID:25968253

  4. Interaction of arsenic species with tropical river aquatic humic substances enriched with aluminum and iron.

    PubMed

    de Oliveira, Lilian Karla; Melo, Camila de Almeida; Fraceto, Leonardo Fernandes; Friese, Kurt; Rosa, André Henrique

    2016-04-01

    The mobility and bioavailability of arsenic (As) are strongly controlled by adsorption/precipitation processes involving metal oxides. However, the organic matter present in the environment, in combination with these oxides, can also play an important role in the cycle of arsenic. This work concerns the interaction between As and two samples of aquatic humic substances (AHS) from tropical rivers. The AHS were extracted as proposed by IHSS, and were characterized by (13)C NMR. The experiments were conducted with the AHS in natura and enriched with metal cations, with different concentrations of As, and complexation capacity was evaluated at three different pH levels (5.0, 7.0, and 9.0). The AHS samples showed similar chemical compositions. The results suggested that there was no interaction between As(III) and AHS in natura or enriched with Al. Low concentrations of As(V) were bound to AHS in natura. For As(III), the complexation capacity of the AHS enriched with Fe was approximately 48 μmol per g of C, while the values for As(V) were in the range 69-80 μmol per grams of C. Fluorescence spectra showed that changes in Eh affected the complexation reactions of As(V) species with AHS.

  5. Tectonics, climate, and the rise and demise of continental aquatic species richness hotspots.

    PubMed

    Neubauer, Thomas A; Harzhauser, Mathias; Georgopoulou, Elisavet; Kroh, Andreas; Mandic, Oleg

    2015-09-15

    Continental aquatic species richness hotspots are unevenly distributed across the planet. In present-day Europe, only two centers of biodiversity exist (Lake Ohrid on the Balkans and the Caspian Sea). During the Neogene, a wide variety of hotspots developed in a series of long-lived lakes. The mechanisms underlying the presence of richness hotspots in different geological periods have not been properly examined thus far. Based on Miocene to Recent gastropod distributions, we show that the existence and evolution of such hotspots in inland-water systems are tightly linked to the geodynamic history of the European continent. Both past and present hotspots are related to the formation and persistence of long-lived lake systems in geological basins or to isolation of existing inland basins and embayments from the marine realm. The faunal evolution within hotspots highly depends on warm climates and surface area. During the Quaternary icehouse climate and extensive glaciations, limnic biodiversity sustained a severe decline across the continent and most former hotspots disappeared. The Recent gastropod distribution is mainly a geologically young pattern formed after the Last Glacial Maximum (19 ky) and subsequent formation of postglacial lakes. The major hotspots today are related to long-lived lakes in preglacially formed, permanently subsiding geological basins. PMID:26305934

  6. Suitability of cytotoxicity endpoints and test microalgal species to disclose the toxic effect of common aquatic pollutants.

    PubMed

    Prado, Raquel; García, Rosa; Rioboo, Carmen; Herrero, Concepción; Cid, Ángeles

    2015-04-01

    Pulse discharges of chemicals to aquatic environments may lead to high concentrations of them in surface waters for short periods of time, but enough to induce toxic effects on aquatic organisms; however, no many methods allow an early warning of toxicity of these agents. Acute effects of one representative chemical from each of three of the main groups of aquatic pollutants (pesticides, metals and pharmaceuticals) are studied on two green microalgal species (Chlamydomonas moewusii and Chlorella vulgaris). Flow cytometry protocols were used to detect the potential application of chlorophyll a fluorescent emission, cell viability, metabolic activity and membrane potential as cytotoxicity endpoints, besides an epifluorescence microscopy protocol for comet assay to detect genotoxicity level of cells. Obtained results confirm the suitability of them for the prospective assessment of the potential cytotoxicity of these aquatic pollutants. The two microalgal species analysed could be used as indicators in toxicity bioassays, being C. moewusii more sensitive than C. vulgaris. Among cell parameters assayed, the metabolic activity and the primary DNA damage stood out as sensitive cytotoxicity endpoints. PMID:25637746

  7. Non-use Economic Values for Little-Known Aquatic Species at Risk: Comparing Choice Experiment Results from Surveys Focused on Species, Guilds, and Ecosystems.

    PubMed

    Rudd, Murray A; Andres, Sheri; Kilfoil, Mary

    2016-09-01

    Accounting for non-market economic values of biological diversity is important to fully assess the benefits of environmental policies and regulations. This study used three choice experiments (species-, guild-, and ecosystem-based surveys) in parallel to quantify non-use values for little-known aquatic species at risk in southern Ontario. Mean willingness-to-pay (WTP) ranged from $9.45 to $21.41 per listing status increment under Canada's Species at Risk Act for both named and unnamed little-known species. Given the broad range of valuable ecosystem services likely to accrue to residents from substantial increases in water quality and the rehabilitation of coastal wetlands, the difference in WTP between species- and ecosystem-based surveys seemed implausibly small. It appeared that naming species-the 'iconization' of species in two of the three surveys-had an important effect on WTP. The results suggest that reasonable annual household-level WTP values for little-known aquatic species may be $10 to $25 per species or $10 to $20 per listing status increment. The results highlighted the utility of using parallel surveys to triangulate on non-use economic values for little-known species at risk. PMID:27294723

  8. Non-use Economic Values for Little-Known Aquatic Species at Risk: Comparing Choice Experiment Results from Surveys Focused on Species, Guilds, and Ecosystems.

    PubMed

    Rudd, Murray A; Andres, Sheri; Kilfoil, Mary

    2016-09-01

    Accounting for non-market economic values of biological diversity is important to fully assess the benefits of environmental policies and regulations. This study used three choice experiments (species-, guild-, and ecosystem-based surveys) in parallel to quantify non-use values for little-known aquatic species at risk in southern Ontario. Mean willingness-to-pay (WTP) ranged from $9.45 to $21.41 per listing status increment under Canada's Species at Risk Act for both named and unnamed little-known species. Given the broad range of valuable ecosystem services likely to accrue to residents from substantial increases in water quality and the rehabilitation of coastal wetlands, the difference in WTP between species- and ecosystem-based surveys seemed implausibly small. It appeared that naming species-the 'iconization' of species in two of the three surveys-had an important effect on WTP. The results suggest that reasonable annual household-level WTP values for little-known aquatic species may be $10 to $25 per species or $10 to $20 per listing status increment. The results highlighted the utility of using parallel surveys to triangulate on non-use economic values for little-known species at risk.

  9. Vegetation development following stream/river restoration: more natural fluvial dynamics and morphology, return of aquatic and riparian plant species?

    NASA Astrophysics Data System (ADS)

    Soons, M. B.

    2012-04-01

    After centuries of human interventions in stream/river dynamics and morphology aimed at optimizing landscapes for agricultural and industrial purposes, new insights have inspired water managers to try and combine stream and river ecosystem functions with the conservation of biodiversity. Around the world, aquatic and riparian species have declined strongly due to pollution, destruction and fragmentation of their habitat, so that biodiversity conservation initiatives primarily focus on habitat restoration. In the past decades many stream and river restoration projects have been carried out and often hydrological dynamics and morphology have been restored to a more natural state. However, the successful restoration of aquatic and riparian habitats very often failed to result in restoration of their biodiversity. This lack of success from a biodiversity conservation perspective is usually attributed to 'dispersal limitation', meaning that the habitat may be restored, but species fail to reach the site and re-colonize it. Especially re-colonization by aquatic and riparian plant species is important, as such species function as ecosystem engineers: their presence alters fluvial dynamics and morphology, generates additional habitat heterogeneity and provides habitat and food for animal species. Following minor disturbances, re-colonization is often possible through locally remaining populations, by seeds in the seed bank or by surviving plant fragments. However, following major disturbances, colonization and establishment from other source populations are necessary. This usually occurs through dispersal of seeds (and in more aquatic species also by dispersal of vegetative fragments) into the restored wetland area. As dispersal occurs predominantly over short distances and source populations of aquatic and riparian species may be lacking in the surroundings, dispersal may be a limiting factor in the development of aquatic and riparian vegetation at a restored site. But

  10. Metal bioaccumulation in aquatic species: quantification of uptake and elimination rate constants using physicochemical properties of metals and physiological characteristics of species.

    PubMed

    Veltman, Karin; Huijbregts, Mark A J; Van Kolck, Maurits; Wang, Wen-Xiong; Hendriks, A Jan

    2008-02-01

    Mechanistic bioaccumulation models are powerful tools in environmental risk assessment as they provide insight in varying accumulation patterns across species, contaminants, and conditions, and they are applicable beyond tested cases. In these models key parameters, as absorption and elimination rate constants, are predicted based on chemical specific properties and physiological characteristics. However, due to the complex environmental behavior of metals, the development of mechanistic bioaccumulation models has lagged behind that for organic chemicals. Absorption and elimination rate constants of organic substances have long been linked to their octanol-water partition coefficient, yet no equivalent quantitative relationships exist for metals. In the present study, we successfully related metal absorption rate constants to a metal specific property, the covalent index, and a species-characteristic, the ventilation rate. This quantitative relationship holds for a wide range of organisms and metals, i.e., 17 aquatic species and 10 metals, suggesting that a generic modeling approach of metal uptake kinetics is feasible for aquatic organisms. In contrast, elimination rate constants show no metal - specific character. Average, weight-corrected elimination rate constants are relatively similar among metals and species, suggesting that a single weight-corrected elimination rate constant can be used in bioaccumulation studies on aquatic species.

  11. Non-use Economic Values for Little-Known Aquatic Species at Risk: Comparing Choice Experiment Results from Surveys Focused on Species, Guilds, and Ecosystems

    NASA Astrophysics Data System (ADS)

    Rudd, Murray A.; Andres, Sheri; Kilfoil, Mary

    2016-09-01

    Accounting for non-market economic values of biological diversity is important to fully assess the benefits of environmental policies and regulations. This study used three choice experiments (species-, guild-, and ecosystem-based surveys) in parallel to quantify non-use values for little-known aquatic species at risk in southern Ontario. Mean willingness-to-pay (WTP) ranged from 9.45 to 21.41 per listing status increment under Canada's Species at Risk Act for both named and unnamed little-known species. Given the broad range of valuable ecosystem services likely to accrue to residents from substantial increases in water quality and the rehabilitation of coastal wetlands, the difference in WTP between species- and ecosystem-based surveys seemed implausibly small. It appeared that naming species—the `iconization' of species in two of the three surveys—had an important effect on WTP. The results suggest that reasonable annual household-level WTP values for little-known aquatic species may be 10 to 25 per species or 10 to 20 per listing status increment. The results highlighted the utility of using parallel surveys to triangulate on non-use economic values for little-known species at risk.

  12. Exploring new Routes for Identifying Phosphorus Species in Terrestrial and Aquatic Ecosystems with 31P NMR

    NASA Astrophysics Data System (ADS)

    Vestergren, Johan; Persson, Per; Sundman, Annelie; Ilstedt, Ulrik; Giesler, Reiner; Schleucher, Jürgen; Gröbner, Gerhard

    2014-05-01

    develop a new method to retrieve and characterize P components in water. By utilizing passive sampling with ion-exchange resin and subsequent analysis with solid state 31P MAS NMR we could identify various P-species extracted from the aquatic systems. By using this approach we can also study the dynamics of the absorption process at the resin as a function of P-species and temperature. This even enabled us to extract the fraction of bound versus free P as a function of temperature for different model P-components (manuscript in preparation). REFERENCES: Gilbert N. Nature 461 716-718 (2009) Vincent AG. et al., Biogeochemistry, 10.1007/s10533-011-9612-0 (2011). Vestergren J et al., Environ. Sci. Technol, 46, 3950-3956, (2012). Vincent AG et al., Plant Soil, 367, 149-162, (2013). Laudon H., et al., Water Resour. Res., 49, 7154-7158, (2013).

  13. Performance of aquatic plant species for phytoremediation of arsenic-contaminated water

    NASA Astrophysics Data System (ADS)

    Jasrotia, Shivakshi; Kansal, Arun; Mehra, Aradhana

    2015-06-01

    This study investigates the effectiveness of aquatic macrophyte and microphyte for phytoremediation of water bodies contaminated with high arsenic concentration. Water hyacinth (Eichhornia crassipes) and two algae (Chlorodesmis sp. and Cladophora sp.) found near arsenic-enriched water bodies were used to determine their tolerance toward arsenic and their effectiveness to uptake arsenic thereby reducing organic pollution in arsenic-enriched wastewater of different concentrations. Parameters like pH, chemical oxygen demand (COD), and arsenic concentration were monitored. The pH of wastewater during the course of phytoremediation remained constant in the range of 7.3-8.4, whereas COD reduced by 50-65 % in a period of 15 days. Cladophora sp. was found to survive up to an arsenic concentration of 6 mg/L, whereas water hyacinth and Chlorodesmis sp. could survive up to arsenic concentrations of 2 and 4 mg/L, respectively. It was also found that during a retention period of 10 days under ambient temperature conditions, Cladophora sp. could bring down arsenic concentration from 6 to <0.1 mg/L, Chlorodesmis sp. was able to reduce arsenic by 40-50 %; whereas, water hyacinth could reduce arsenic by only 20 %. Cladophora sp. is thus suitable for co-treatment of sewage and arsenic-enriched brine in an algal pond having a retention time of 10 days. The identified plant species provides a simple and cost-effective method for application in rural areas affected with arsenic problem. The treated water can be used for irrigation.

  14. Predicting locations of rare aquatic species’ habitat with a combination of species-specific and assemblage-based models

    USGS Publications Warehouse

    McKenna, James E.; Carlson, Douglas M.; Payne-Wynne, Molly L.

    2013-01-01

    Aim: Rare aquatic species are a substantial component of biodiversity, and their conservation is a major objective of many management plans. However, they are difficult to assess, and their optimal habitats are often poorly known. Methods to effectively predict the likely locations of suitable rare aquatic species habitats are needed. We combine two modelling approaches to predict occurrence and general abundance of several rare fish species. Location: Allegheny watershed of western New York State (USA) Methods: Our method used two empirical neural network modelling approaches (species specific and assemblage based) to predict stream-by-stream occurrence and general abundance of rare darters, based on broad-scale habitat conditions. Species-specific models were developed for longhead darter (Percina macrocephala), spotted darter (Etheostoma maculatum) and variegate darter (Etheostoma variatum) in the Allegheny drainage. An additional model predicted the type of rare darter-containing assemblage expected in each stream reach. Predictions from both models were then combined inclusively and exclusively and compared with additional independent data. Results Example rare darter predictions demonstrate the method's effectiveness. Models performed well (R2 ≥ 0.79), identified where suitable darter habitat was most likely to occur, and predictions matched well to those of collection sites. Additional independent data showed that the most conservative (exclusive) model slightly underestimated the distributions of these rare darters or predictions were displaced by one stream reach, suggesting that new darter habitat types were detected in the later collections. Main conclusions Broad-scale habitat variables can be used to effectively identify rare species' habitats. Combining species-specific and assemblage-based models enhances our ability to make use of the sparse data on rare species and to identify habitat units most likely and least likely to support those species

  15. Bioaccumulation and tissue distribution of a quaternary ammonium surfactant in three aquatic species

    SciTech Connect

    Knezovich, J.P.; Lawton, M.P.; Inouye, L.S.

    1989-01-01

    Quaternary ammonium compounds (QACs) are commonly used as surfactants in drilling muds and fabric softeners and as biocides in antiseptics and disinfectants. QACs and cationic polyelectrolytes elicit acute toxic effects in aquatic organisms by disrupting the structure and function of gill tissues, which may result in the suffocation of the organism. Little information is available, however, on the relative availability and distribution of QACs in the tissues of aquatic organisms. Information of this nature is required to understand the potential consequences of releases of sublethal concentrations of QACs into the aquatic environment. In this study, hexadecylpyridinium bromide (HPB; CAS 140-72-7) was selected as a compound for initial study because it belongs to a chemical class (alkylpyridinium QACs) that includes the most toxic and environmentally persistent QACs. Clams, minnows, and tadpoles were chosen as test organisms to define the relative availability of HPB to organisms that occupy distinctly different ecological niches.

  16. Fate of engineered cerium oxide nanoparticles in an aquatic environment and their toxicity toward 14 ciliated protist species.

    PubMed

    Zhang, Wei; Pu, Zhichao; Du, Songyan; Chen, Yongsheng; Jiang, Lin

    2016-05-01

    The potential environmental impacts of engineered cerium oxide nanoparticles (CeO2 NPs) on aquatic organisms have remained largely unknown. Therefore, the laboratory study featured herein was performed to determine the fate of CeO2 NPs in an aquatic environment and their toxicity towards 14 different ciliated protist species at a specified population level. An investigation of 48 h aggregation kinetics in the Dryl's solution showed the CeO2 NPs to be relatively stable. The pH values in three test medium were too far away from PZC, which explained the stability of CeO2 NPs. CeO2 NPs generally elicited more toxicity with increasing NP concentration, following certain dose-response relationships. Nano-CeO2 resulted in greater toxicity in a particle state than when added as bulk material. LC50 values showed a negative correlation with the surface-to-volume ratio for these protists, suggesting that surface adsorption of CeO2 NPs might contribute to the observed toxicity. Additionally, acute toxic responses of 14 ciliated protist species to CeO2 NPs were not significantly phylogenetically conserved. The results of these observations provide a better insight into the potential risks of CeO2 NPs in an aquatic environment.

  17. Fate of engineered cerium oxide nanoparticles in an aquatic environment and their toxicity toward 14 ciliated protist species.

    PubMed

    Zhang, Wei; Pu, Zhichao; Du, Songyan; Chen, Yongsheng; Jiang, Lin

    2016-05-01

    The potential environmental impacts of engineered cerium oxide nanoparticles (CeO2 NPs) on aquatic organisms have remained largely unknown. Therefore, the laboratory study featured herein was performed to determine the fate of CeO2 NPs in an aquatic environment and their toxicity towards 14 different ciliated protist species at a specified population level. An investigation of 48 h aggregation kinetics in the Dryl's solution showed the CeO2 NPs to be relatively stable. The pH values in three test medium were too far away from PZC, which explained the stability of CeO2 NPs. CeO2 NPs generally elicited more toxicity with increasing NP concentration, following certain dose-response relationships. Nano-CeO2 resulted in greater toxicity in a particle state than when added as bulk material. LC50 values showed a negative correlation with the surface-to-volume ratio for these protists, suggesting that surface adsorption of CeO2 NPs might contribute to the observed toxicity. Additionally, acute toxic responses of 14 ciliated protist species to CeO2 NPs were not significantly phylogenetically conserved. The results of these observations provide a better insight into the potential risks of CeO2 NPs in an aquatic environment. PMID:26986089

  18. Sensitivity and accuracy of high-throughput metabarcoding methods used to describe aquatic communities for early detection of invasve fish species

    EPA Science Inventory

    For early detection biomonitoring of aquatic invasive species, sensitivity to rare individuals and accurate, high-resolution taxonomic classification are critical to minimize Type I and II detection errors. Given the great expense and effort associated with morphological identifi...

  19. A FRAMEWORK FOR ASSESSING THE HAZARD OF PHARMACEUTICAL MATERIALS TO AQUATIC SPECIES

    EPA Science Inventory

    There are a wide variety of existing ecotoxicity methods that may be used to address potential impacts of human pharmaceuticals on populations of aquatic organisms. Several key methods, using algae, invertebrates, or fish, focus upon measuring population-relevent effects (e.g. su...

  20. A simultaneous multiple species acute toxicity test comparing relative sensitivities of six aquatic organisms to HgCl{sub 2}

    SciTech Connect

    McCrary, J.E.; Heagler, M.G.

    1995-12-31

    In the last few years there has been concern in the scientific community about observed declines in some amphibian species. These population declines could be reflecting a global phenomenon due to a general class sensitivity or may be part of a natural cycle. The suggestion of an overall greater sensitivity of amphibians is not supported. Studies show that amphibians, as a class, are neither more or less susceptible than fish to environmental conditions. Mercury has been found to be one of the most toxic of the heavy metals introduced into amphibian breeding waters. Six aquatic species were simultaneously exposed in a comparative acute toxicity test with mercury chloride: three amphibians, Rana catesbeiana (bullfrog), R. clamitans (green frog), and R. sphenocephala (southern leopard frog, formally classified as R. utricularia); two fish, Gambusia affinis (mosquitofish) and Notemigonus crysoleucas (golden shiner); one aquatic aligochaete, Lumbriculus variegatus (aquatic earthworm). The five test concentrations used were 1.4, 3.9, 12.0, 110.0, and 487.0 {micro}g Hg/L respectively. Ten organisms per species were randomly placed into the six test tanks (control and five concentrations), each species in a separate chamber. The resultant LC50-96hr values produced the following rank order: R. sphenocephala, 6.59 {micro}g Hg/L; R. clamitans, 14.7 {micro}g Hg/L; N. crysoleucas, 16.75 {micro}g Hg/L; L. variegatus, 43.72,ug Hg/L; G. affinis, 52.62 {micro}g Hg/L; R. catesbeiana, 63.36 {micro}g Hg/L. No general organism class sensitivity trend, for amphibians, was developed from this data, contrary to the implicit suggestions of some researchers.

  1. Temperature-size responses match latitudinal-size clines in arthropods, revealing critical differences between aquatic and terrestrial species.

    PubMed

    Horne, Curtis R; Hirst, Andrew G; Atkinson, David

    2015-04-01

    Two major intraspecific patterns of adult size variation are plastic temperature-size (T-S) responses and latitude-size (L-S) clines. Yet, the degree to which these co-vary and share explanatory mechanisms has not been systematically evaluated. We present the largest quantitative comparison of these gradients to date, and find that their direction and magnitude co-vary among 12 arthropod orders (r(2) = 0.72). Body size in aquatic species generally reduces with both warming and decreasing latitude, whereas terrestrial species have much reduced and even opposite gradients. These patterns support the prediction that oxygen limitation is a major controlling factor in water, but not in air. Furthermore, voltinism explains much of the variation in T-S and L-S patterns in terrestrial but not aquatic species. While body size decreases with warming and with decreasing latitude in multivoltine terrestrial arthropods, size increases on average in univoltine species, consistent with predictions from size vs. season-length trade-offs.

  2. Predicted no-effect concentrations for mercury species and ecological risk assessment for mercury pollution in aquatic environment.

    PubMed

    Du, Meng; Wei, Dongbin; Tan, Zhuowei; Lin, Aiwu; Du, Yuguo

    2015-02-01

    Mercury (Hg) exists in different chemical forms presenting varied toxic potentials. It is necessary to explore an ecological risk assessment method for different mercury species in aquatic environment. The predicted no-effect concentrations (PNECs) for Hg(II) and methyl mercury (MeHg) in the aqueous phase, calculated using the species sensitivity distribution method and the assessment factor method, were 0.39 and 6.5×10(-3)μg/L, respectively. The partition theory of Hg between sediment and aqueous phases was considered, along with PNECs for the aqueous phase to conduct an ecological risk assessment for Hg in the sediment phase. Two case studies, one in China and one in the Western Black Sea, were conducted using these PNECs. The toxicity of mercury is heavily dependent on their forms, and their potential ecological risk should be respectively evaluated on the basis of mercury species. PMID:25662241

  3. Development of static system procedures to study aquatic biofilms and their responses to disinfection and invading species

    NASA Technical Reports Server (NTRS)

    Smithers, G. A.

    1992-01-01

    The microbial ecology facility in the Analytical and Physical Chemistry Branch at Marshall Space Flight Center is tasked with anticipation of potential microbial problems (and opportunities to exploit microorganisms) which may occur in partially closed systems such as space station/vehicles habitats and in water reclamation systems therein, with particular emphasis on the degradation of materials. Within this context, procedures for microbial biofilm research are being developed. Reported here is the development of static system procedures to study aquatic biofilms and their responses to disinfection and invading species. Preliminary investigations have been completed. As procedures are refined, it will be possible to focus more closely on the elucidation of biofilm phenomena.

  4. Molecular ecology of aquatic microbes

    SciTech Connect

    1994-12-31

    Abstracts of reports are presented from a meeting on Molecular Ecology of Aquatic Microbes. Topics included: opportunities offered to aquatic ecology by molecular biology; the role of aquatic microbes in biogeochemical cycles; characterization of the microbial community; the effect of the environment on aquatic microbes; and the targeting of specific biological processes.

  5. Comparative sensitivity of aquatic invertebrate and vertebrate species to wastewater from an operational coal mine in central Queensland, Australia.

    PubMed

    Lanctôt, C; Wilson, S P; Fabbro, L; Leusch, F D L; Melvin, S D

    2016-07-01

    Coal excavation and refinement processes generate substantial volumes of contaminated effluent that may be detrimental to aquatic ecosystems. As such, understanding the impacts of coal mine water releases on aquatic animals and ecosystems is essential for effectively managing and protecting neighboring environments. Such information will ultimately be applied towards developing ongoing monitoring strategies that are protective of native wildlife. Despite intensive mining operations in Australia, few studies have documented toxicity associated with coal mine wastewater (CMW) on native species. To address existing knowledge gaps, we investigated acute toxicity (48-96h) using eight native invertebrate species and sub-chronic effects (2 week) using three vertebrate species following exposure to wastewater from two dams (CMW1 and CMW2) located at an open-cut coal mine licensed to discharge into the Fitzroy catchment (Queensland, Australia). Wastewater from these sites is characterized by elevated conductivity, pH, sulfates as well as relatively high total and dissolved metal(loid)s (including As, Al, B, Cu, Mn, Ni, Se and Zn). Acute exposures revealed cladocerans (Daphnia carinata) and planarians (Dugesia sp.) to be the most sensitive species, exhibiting significant mortality after 48 and 96h exposure to CMW2, respectively. Neither wastewater was found to elicit acute toxicity in vertebrates, but a range of sub-lethal morphological effects were observed following the sub-chronic exposures. The overall response pattern was characterized by decreased condition factor and hepatosomatic index in the fish Hypseleotris compressa and Pseudomugil signifier, and in Limnodynastes peronii tadpoles. Tadpoles were generally more sensitive compared to the two fish species. Differences in responses were observed amongst CMW1 and CMW2, which likely relates to differences in physico-chemical properties between sites. Our results have identified several candidate vertebrate and

  6. Comparative sensitivity of aquatic invertebrate and vertebrate species to wastewater from an operational coal mine in central Queensland, Australia.

    PubMed

    Lanctôt, C; Wilson, S P; Fabbro, L; Leusch, F D L; Melvin, S D

    2016-07-01

    Coal excavation and refinement processes generate substantial volumes of contaminated effluent that may be detrimental to aquatic ecosystems. As such, understanding the impacts of coal mine water releases on aquatic animals and ecosystems is essential for effectively managing and protecting neighboring environments. Such information will ultimately be applied towards developing ongoing monitoring strategies that are protective of native wildlife. Despite intensive mining operations in Australia, few studies have documented toxicity associated with coal mine wastewater (CMW) on native species. To address existing knowledge gaps, we investigated acute toxicity (48-96h) using eight native invertebrate species and sub-chronic effects (2 week) using three vertebrate species following exposure to wastewater from two dams (CMW1 and CMW2) located at an open-cut coal mine licensed to discharge into the Fitzroy catchment (Queensland, Australia). Wastewater from these sites is characterized by elevated conductivity, pH, sulfates as well as relatively high total and dissolved metal(loid)s (including As, Al, B, Cu, Mn, Ni, Se and Zn). Acute exposures revealed cladocerans (Daphnia carinata) and planarians (Dugesia sp.) to be the most sensitive species, exhibiting significant mortality after 48 and 96h exposure to CMW2, respectively. Neither wastewater was found to elicit acute toxicity in vertebrates, but a range of sub-lethal morphological effects were observed following the sub-chronic exposures. The overall response pattern was characterized by decreased condition factor and hepatosomatic index in the fish Hypseleotris compressa and Pseudomugil signifier, and in Limnodynastes peronii tadpoles. Tadpoles were generally more sensitive compared to the two fish species. Differences in responses were observed amongst CMW1 and CMW2, which likely relates to differences in physico-chemical properties between sites. Our results have identified several candidate vertebrate and

  7. Evaluation of in silico development of aquatic toxicity species sensitivity distributions (SSDs)

    EPA Science Inventory

    Determining the sensitivity of a diversity of species to environmental contaminants continues to be a significant challenge in ecological risk assessment because toxicity data are generally limited to a few standard test species. This study assessed whether species sensitivity di...

  8. ASSESSING CONTAMINANT SENSITIVITY OF ENDANGERED AND THREATENED AQUATIC SPECIES WITH ACUTE TOXICITY TESTS

    EPA Science Inventory

    Assessment of contaminant impacts to endangered and threatened (listed) species requires understanding of a species' sensitivity to particular chemicals. The most direct approach would be to determine the sensitivity of a listed species to a particular contaminant or perturbation...

  9. Assessing Contaminant Sensitivity of Endangered and Threatened Aquatic Species: Part I. Acute Toxicity of Five Chemicals

    EPA Science Inventory

    This paper reports on the results of acute toxicity tests conducted with common surrogate species, and several species of threatened and endangered species for which there were excess artificially propagated stock to allow direct testing.

  10. Evaluation of in silico development of aquatic toxicity species sensitivity distributions

    EPA Science Inventory

    Determining the sensitivity of a diversity of species to environmental contaminants continues to be a significant challenge in ecological risk assessment because toxicity data are generally limited to a few standard test species. This study assessed whether species sensitivity d...

  11. Medaka (Oryzias latipes) as a sentinel species for aquatic animals: Medaka cells exhibit a similar genotoxic response as North Atlantic right whale cells★

    PubMed Central

    Wise, John Pierce; Wise, Sandra S.; Goodale, Britton C.; Shaffiey, Fariba; Kraus, Scott; Walter, Ronald B.

    2015-01-01

    Hexavalent chromium (Cr(VI)) is emerging as a major concern for aquatic environments, particularly marine environments. Medaka (Oryzias latipes) has been used as a model species for human and aquatic health, including the marine environment, though few studies have directly compared toxicological responses in medaka to humans or other aquatic species. We used a medaka fin cell line to compare the genotoxic response of medaka to Cr(VI) to the response observed in North Atlantic right whale cells to see if responses in medaka were similar to those of other aquatic species, particularly aquatic mammals. We used the production of chromosomal aberrations as a measure of genotoxicity. We found that in medaka cells, concentrations of 1, 5 and 10 μM sodium chromate damaged 17, 32 and 43% of metaphases, respectively and these same concentrations 1, 2.5, 5 and 10 μM sodium chromate damaged 14, 24 and 49% of metaphases, respectively, in North Atlantic right whale lung cells and 11, 32 and 41% of metaphases, respectively, in North Atlantic right whale testes cells. These data show that genotoxic responses in medaka are comparable to those seen in North Atlantic right whale cells, consistent with the hypothesis that medaka are a useful model for other aquatic species. PMID:18930840

  12. Determination of antimicrobial and heavy metal resistance profiles of some bacteria isolated from aquatic amphibian and reptile species.

    PubMed

    Hacioglu, Nurcihan; Tosunoglu, Murat

    2014-01-01

    The aim of the present study was to determine the level of antibiotic resistance patterns and distribution of heavy metal resistance of bacterial isolates from aquatic animals (Lissotriton vulgaris, Pelophylax ridibundus, Emys orbicularis, Mauremys rivulata, and Natrix natrix) in Turkey (Kavak Delta). A total of 153 bacteria have been successfully isolated from cloaca and oral samples of the aquatic amphibians and reptilians which were found, namely, Aeromonas sp. (n = 29), Plesiomonas sp. (n = 7), Vibrio sp. (n = 12), Citrobacter sp. (n = 12), Enterobacter sp. (n = 11), Escherichia sp. (n = 22), Klebsiella sp. (n = 22), Edwardsiella sp. (n = 6), Hafnia sp. (n = 1), Proteus sp. (n = 19), Providencia sp. (n = 8), and Pseudomonas sp. (n = 4). In terms of antibiotic and heavy metal susceptibility testing, each isolate was tested against 12 antibiotics and 4 metals. There was a high incidence of resistance to cefoxitin (46.40 %), ampicillin (44.44 %), erythromycin (35.29 %), and a low incidence of resistance to gentamicin (6.53 %), kanamycin (8.49 %), chloramphenicol (9.15 %), and cefotaxime (10.45 %). The multiple antibiotic resistance index of each bacterial species indicated that bacteria from raised amphibians and reptiles have been exposed to tested antibiotics, with results ranging from 0 to 0.58. Most isolates showed tolerance to different concentrations of heavy metals, and minimal inhibition concentrations ranged from100 to >3,200 μg/mL. According to these results, a significant occurrence of bacteria in the internal organs of reptiles and amphibians, with a high incidence of resistance against antibiotics and heavy metals, may risk aquatic animals and the public health. These data appoint the importance of epidemiological surveillance and microbiological monitoring and reinforce the need to implement environment protection programs for amphibian and reptile species. PMID:23959346

  13. Determination of antimicrobial and heavy metal resistance profiles of some bacteria isolated from aquatic amphibian and reptile species.

    PubMed

    Hacioglu, Nurcihan; Tosunoglu, Murat

    2014-01-01

    The aim of the present study was to determine the level of antibiotic resistance patterns and distribution of heavy metal resistance of bacterial isolates from aquatic animals (Lissotriton vulgaris, Pelophylax ridibundus, Emys orbicularis, Mauremys rivulata, and Natrix natrix) in Turkey (Kavak Delta). A total of 153 bacteria have been successfully isolated from cloaca and oral samples of the aquatic amphibians and reptilians which were found, namely, Aeromonas sp. (n = 29), Plesiomonas sp. (n = 7), Vibrio sp. (n = 12), Citrobacter sp. (n = 12), Enterobacter sp. (n = 11), Escherichia sp. (n = 22), Klebsiella sp. (n = 22), Edwardsiella sp. (n = 6), Hafnia sp. (n = 1), Proteus sp. (n = 19), Providencia sp. (n = 8), and Pseudomonas sp. (n = 4). In terms of antibiotic and heavy metal susceptibility testing, each isolate was tested against 12 antibiotics and 4 metals. There was a high incidence of resistance to cefoxitin (46.40 %), ampicillin (44.44 %), erythromycin (35.29 %), and a low incidence of resistance to gentamicin (6.53 %), kanamycin (8.49 %), chloramphenicol (9.15 %), and cefotaxime (10.45 %). The multiple antibiotic resistance index of each bacterial species indicated that bacteria from raised amphibians and reptiles have been exposed to tested antibiotics, with results ranging from 0 to 0.58. Most isolates showed tolerance to different concentrations of heavy metals, and minimal inhibition concentrations ranged from100 to >3,200 μg/mL. According to these results, a significant occurrence of bacteria in the internal organs of reptiles and amphibians, with a high incidence of resistance against antibiotics and heavy metals, may risk aquatic animals and the public health. These data appoint the importance of epidemiological surveillance and microbiological monitoring and reinforce the need to implement environment protection programs for amphibian and reptile species.

  14. Low Frequency Vibrations Induce Malformations in Two Aquatic Species in a Frequency-, Waveform-, and Direction-Specific Manner

    PubMed Central

    Vandenberg, Laura N.; Stevenson, Claire; Levin, Michael

    2012-01-01

    Environmental toxicants such as industrial wastes, air particulates from machinery and transportation vehicles, and pesticide run-offs, as well as many chemicals, have been widely studied for their effects on human and wildlife populations. Yet other potentially harmful environmental pollutants such as electromagnetic pulses, noise and vibrations have remained incompletely understood. Because developing embryos undergo complex morphological changes that can be affected detrimentally by alterations in physical forces, they may be particularly susceptible to exposure to these types of pollutants. We investigated the effects of low frequency vibrations on early embryonic development of two aquatic species, Xenopus laevis (frogs) and Danio rerio (zebrafish), specifically focusing on the effects of varying frequencies, waveforms, and applied direction. We observed treatment-specific effects on the incidence of neural tube defects, left-right patterning defects and abnormal tail morphogenesis in Xenopus tadpoles. Additionally, we found that low frequency vibrations altered left-right patterning and tail morphogenesis, but did not induce neural tube defects, in zebrafish. The results of this study support the conclusion that low frequency vibrations are toxic to aquatic vertebrates, with detrimental effects observed in two important model species with very different embryonic architectures. PMID:23251546

  15. Bioassays with terrestrial and aquatic species as monitoring tools of hydrocarbon degradation.

    PubMed

    Bori, Jaume; Vallès, Bettina; Ortega, Lina; Riva, Maria Carme

    2016-09-01

    In this study chemical analyses and ecotoxicity tests were applied for the assessment of a heavily hydrocarbon-contaminated soil prior and after the application of a remediation procedure that consisted in the stimulation of soil autochthonous populations of hydrocarbon degraders in static-ventilated biopiles. Terrestrial bioassays were applied in mixtures of test soils and artificial control soil and studied the survival and reproduction of Eisenia fetida and the avoidance response of E. fetida and Folsomia candida. Effects on aquatic organisms were studied by means of acute tests with Vibrio fischeri, Raphidocelis subcapitata, and Daphnia magna performed on aqueous elutriates from test soils. The bioremediation procedure led to a significant reduction in the concentration of hydrocarbons (from 34264 to 3074 mg kg(-1), i.e., 91 % decrease) and toxicity although bioassays were not able to report a percentage decrease of toxicity as high as the percentage reduction. Sublethal tests proved the most sensitive terrestrial bioassays and avoidance tests with earthworms and springtails showed potential as monitoring tools of hydrocarbon remediation due to their high sensitivity and short duration. The concentrations of hydrocarbons in water extracts from test soils were 130 and 100 μg L(-1) before and after remediation, respectively. Similarly to terrestrial tests, most aquatic bioassays detected a significant reduction in toxicity, which was almost negligible at the end of the treatment. D. magna survival was the most affected by soil elutriates although toxicity to the crustacean was associated to the salinity of the samples rather than to the concentration of hydrocarbons. Ecotoxicity tests with aqueous soil elutriates proved less relevant in the assessment of hydrocarbon-contaminated soils due to the low hydrosolubility of hydrocarbons and the influence of the physicochemical parameters of the aquatic medium.

  16. Bioassays with terrestrial and aquatic species as monitoring tools of hydrocarbon degradation.

    PubMed

    Bori, Jaume; Vallès, Bettina; Ortega, Lina; Riva, Maria Carme

    2016-09-01

    In this study chemical analyses and ecotoxicity tests were applied for the assessment of a heavily hydrocarbon-contaminated soil prior and after the application of a remediation procedure that consisted in the stimulation of soil autochthonous populations of hydrocarbon degraders in static-ventilated biopiles. Terrestrial bioassays were applied in mixtures of test soils and artificial control soil and studied the survival and reproduction of Eisenia fetida and the avoidance response of E. fetida and Folsomia candida. Effects on aquatic organisms were studied by means of acute tests with Vibrio fischeri, Raphidocelis subcapitata, and Daphnia magna performed on aqueous elutriates from test soils. The bioremediation procedure led to a significant reduction in the concentration of hydrocarbons (from 34264 to 3074 mg kg(-1), i.e., 91 % decrease) and toxicity although bioassays were not able to report a percentage decrease of toxicity as high as the percentage reduction. Sublethal tests proved the most sensitive terrestrial bioassays and avoidance tests with earthworms and springtails showed potential as monitoring tools of hydrocarbon remediation due to their high sensitivity and short duration. The concentrations of hydrocarbons in water extracts from test soils were 130 and 100 μg L(-1) before and after remediation, respectively. Similarly to terrestrial tests, most aquatic bioassays detected a significant reduction in toxicity, which was almost negligible at the end of the treatment. D. magna survival was the most affected by soil elutriates although toxicity to the crustacean was associated to the salinity of the samples rather than to the concentration of hydrocarbons. Ecotoxicity tests with aqueous soil elutriates proved less relevant in the assessment of hydrocarbon-contaminated soils due to the low hydrosolubility of hydrocarbons and the influence of the physicochemical parameters of the aquatic medium. PMID:27312898

  17. Relevance of risk predictions derived from a chronic species sensitivity distribution with cadmium to aquatic populations and ecosystems

    USGS Publications Warehouse

    Mebane, C.A.

    2010-01-01

    Criteria to protect aquatic life are intended to protect diverse ecosystems, but in practice are usually developed from compilations of single-species toxicity tests using standard test organisms that were tested in laboratory environments. Species sensitivity distributions (SSDs) developed from these compilations are extrapolated to set aquatic ecosystem criteria. The protectiveness of the approach was critically reviewed with a chronic SSD for cadmium comprising 27 species within 21 genera. Within the data set, one genus had lower cadmium effects concentrations than the SSD fifth percentile-based criterion, so in theory this genus, the amphipod Hyalella, could be lost or at least allowed some level of harm by this criteria approach. However, population matrix modeling projected only slightly increased extinction risks for a temperate Hyalella population under scenarios similar to the SSD fifth percentile criterion. The criterion value was further compared to cadmium effects concentrations in ecosystem experiments and field studies. Generally, few adverse effects were inferred from ecosystem experiments at concentrations less than the SSD fifth percentile criterion. Exceptions were behavioral impairments in simplified food web studies. No adverse effects were apparent in field studies under conditions that seldom exceeded the criterion. At concentrations greater than the SSD fifth percentile, the magnitudes of adverse effects in the field studies were roughly proportional to the laboratory-based fraction of species with adverse effects in the SSD. Overall, the modeling and field validation comparisons of the chronic criterion values generally supported the relevance and protectiveness of the SSD fifth percentile approach with cadmium. ?? 2009 Society for Risk Analysis.

  18. Acute Upper Thermal Limits of Three Aquatic Invasive Invertebrates: Hot Water Treatment to Prevent Upstream Transport of Invasive Species

    NASA Astrophysics Data System (ADS)

    Beyer, Jessica; Moy, Philip; de Stasio, Bart

    2011-01-01

    Transport of aquatic invasive species (AIS) by boats traveling up rivers and streams is an important mechanism of secondary spread of AIS into watersheds. Because physical barriers to AIS movement also prevent navigation, alternate methods for preventing spread are necessary while allowing upstream navigation. One promising approach is to lift boats over physical barriers and then use hot water immersion to kill AIS attached to the hull, motor, or fishing gear. However, few data have been published on the acute upper thermal tolerance limits of potential invaders treated in this manner. To test the potential effectiveness of this approach for a planned boat lift on the Fox River of northeastern WI, USA, acute upper thermal limits were determined for three AIS, adult zebra mussels ( Dreissena polymorpha), quagga mussels ( Dreissena rostriformis bugensis), and spiny water fleas ( Bythotrephes longimanus) from the local area employing temperatures from 32 to 54°C and immersion times from 1 to 20 min. Mortality was determined after immersion followed by a 20-min recovery period. Immersion at 43°C for at least 5 min was required to ensure 100% mortality for all three species, but due to variability in the response by Bythotrephes a 10 min immersion would be more reliable. Overall there were no significant differences between the three species in acute upper thermal limits. Heated water can be an efficient, environmentally sound, and cost effective method of controlling AIS potentially transferred by boats, and our results should have both specific and wide-ranging applications in the prevention of the spread of aquatic invasive species.

  19. Nutritional and Antinutritional Composition of the Five Species of Aquatic Edible Insects Consumed in Manipur, India

    PubMed Central

    Shantibala, T.; Lokeshwari, R. K.; Debaraj, H.

    2014-01-01

    The people living in Manipur have a distinct identity, culture, and food habits. They have a prototype culture of eating insects. In our study, the nutritive contents of five potentially-edible aquatic insects, Lethocerus indicus (Lepeletier and Serville) (Hemiptera: Belostomatidae), Laccotrephes maculatus (F.) (Nepidae), Hydrophilus olivaceous (F.) (Coleoptera: Dytiscidae), Cybister tripunctatus (Olivier), and Crocothemis servilia (Drury) (Odonata: Libellulidae), were analyzed to inform consumers about the nutritional quality of the insects and the suggested quantity of their intake. A good amount of protein content and high gross energy was recorded among the insects. The results showed high levels of sodium, calcium, and magnesium present in the insects, indicating that they are a good source of minerals. Antinutritional properties of these insects were below 0.52%, which is a non-toxic level. Aquatic insects, such as C. tripunctatus, also possesses strong antioxidant activity (110 µg/mL). Therefore, these insects can play a major role in food security, health, and environment management. It is essential to cultivate edible insects to maintain their population sustainability. PMID:25373161

  20. Nutritional and antinutritional composition of the five species of aquatic edible insects consumed in Manipur, India.

    PubMed

    Shantibala, T; Lokeshwari, R K; Debaraj, H

    2014-01-26

    The people living in Manipur have a distinct identity, culture, and food habits. They have a prototype culture of eating insects. In our study, the nutritive contents of five potentially-edible aquatic insects, Lethocerus indicus (Lepeletier and Serville) (Hemiptera: Belostomatidae), Laccotrephes maculatus (F.) (Nepidae), Hydrophilus olivaceous (F.) (Coleoptera: Dytiscidae), Cybister tripunctatus (Olivier), and Crocothemis servilia (Drury) (Odonata: Libellulidae), were analyzed to inform consumers about the nutritional quality of the insects and the suggested quantity of their intake. A good amount of protein content and high gross energy was recorded among the insects. The results showed high levels of sodium, calcium, and magnesium present in the insects, indicating that they are a good source of minerals. Antinutritional properties of these insects were below 0.52%, which is a non-toxic level. Aquatic insects, such as C. tripunctatus, also possesses strong antioxidant activity (110 µg/mL). Therefore, these insects can play a major role in food security, health, and environment management. It is essential to cultivate edible insects to maintain their population sustainability.

  1. Advancing capability for bioassessment using DNA metabarcoding: Application to aquatic invasive species monitoring

    EPA Science Inventory

    Characterizing biological communities by their constituent species is fundamental to biological monitoring and ecological condition assessment. Finding and identifying rare species is a long-standing challenge for monitoring programs. Nevertheless, conducting surveys that can des...

  2. Subtle temperature differences may well determine who wins: a story of three submerged aquatic plant species

    Technology Transfer Automated Retrieval System (TEKTRAN)

    As temperatures increases globally, shifts in the distribution of plant species are expected, with unknown effects on invasive species abundance. It is then of value to understand the role increased temperature may have on invasive species. Although nonhomeothermic organisms are the mercy of environ...

  3. EXTRAPOLATION OF ACUTE TOXICITY AMONG AQUATIC SPECIES BASED ON MECHANISM OF ACTION

    EPA Science Inventory

    Presentation provides inter-species QSARs for acute toxicity to ciliates, fish and daphnia...The inter-species QSARs can be also useful in the analysis of the relative species sensitivity to a variety of pollutants and will be useful in assisting in risk assessments of potential ...

  4. Assessing Contaminant Sensitivity of Endangered and Threatened Aquatic Species: Part I. Acute Toxicity of Five Chemicals

    EPA Science Inventory

    Early life-stage toxicity tests with copper and pentachlorophenol (PCP) were conducted with two species listed under the U.S. Endangered Species Act (fountain darter, Etheostoma fonticola, and spotfin chub, Cyprinella monacha) and two surrogate species (fathead minnow, Pimephales...

  5. Seasonal trends in growth and biomass accumulation of selected nutrients and metals in six species of emergent aquatic macrophytes

    SciTech Connect

    Behrends, L.L.; Bailey, E.; Bulls, M.J.; Coonrod, H.S.; Sikora, F.J.

    1996-05-01

    Growth and biomass accumulation of selected nutrients and trace metals were monitored for six species of aquatic macrophytes during June, August and November, 1993. Plant species were cultivated in two polyculture treatments, each replicated three times. Polyculture I consisted of Scirpus acutus (hardstem bullrush), Phragmites communes (common reed), and Phalaris arundinacea (canary grass). Polyculture H consisted of Typha spp. (cattail), Scirpus atrovirens (green bullrush), and Scirpus cyperinus (wool grass). Each of the six cells (6 x 9 x 0.6 m), was operated as a gravel-substrate, subsurface-flow wetlands in a continuous recirculating mode. At six week intervals, macro, micro and trace elements were dissolved and added to the sump of the recirculating system. On each of three sampling dates, replicate shoot and root samples were collected, segregated by species and tissue type (roots, rhizomes, stems and leaves), and prepared for gravimetric biomass estimates and chemical analysis. Tissue specific concentrations of N, P, K, Ca, Mg, Fe, Mn, Zn and Cu, were determined on each date for each species and tissue type. Results will be discussed with respect to species specific growth rates, biomass accumulation, and seasonal uptake and translocation of plant nutrients.

  6. Fish species of greatest conservation need in wadeable Iowa streams: current status and effectiveness of Aquatic Gap Program distribution models

    USGS Publications Warehouse

    Sindt, Anthony R.; Pierce, Clay; Quist, Michael C.

    2012-01-01

    Effective conservation of fish species of greatest conservation need (SGCN) requires an understanding of species–habitat relationships and distributional trends. Thus, modeling the distribution of fish species across large spatial scales may be a valuable tool for conservation planning. Our goals were to evaluate the status of 10 fish SGCN in wadeable Iowa streams and to test the effectiveness of Iowa Aquatic Gap Analysis Project (IAGAP) species distribution models. We sampled fish assemblages from 86 wadeable stream segments in the Mississippi River drainage of Iowa during 2009 and 2010 to provide contemporary, independent fish species presence–absence data. The frequencies of occurrence in stream segments where species were historically documented varied from 0.0% for redfin shiner Lythrurus umbratilis to 100.0% for American brook lampreyLampetra appendix, with a mean of 53.0%, suggesting that the status of Iowa fish SGCN is highly variable. Cohen's kappa values and other model performance measures were calculated by comparing field-collected presence–absence data with IAGAP model–predicted presences and absences for 12 fish SGCN. Kappa values varied from 0.00 to 0.50, with a mean of 0.15. The models only predicted the occurrences of banded darterEtheostoma zonale, southern redbelly dace Phoxinus erythrogaster, and longnose daceRhinichthys cataractae more accurately than would be expected by chance. Overall, the accuracy of the twelve models was low, with a mean correct classification rate of 58.3%. Poor model performance probably reflects the difficulties associated with modeling the distribution of rare species and the inability of the large-scale habitat variables used in IAGAP models to explain the variation in fish species occurrences. Our results highlight the importance of quantifying the confidence in species distribution model predictions with an independent data set and the need for long-term monitoring to better understand the

  7. USGS Nonindigenous Aquatic Species database with a focus on the introduced fishes of the lower Tennessee and Cumberland drainages

    USGS Publications Warehouse

    Fuller, Pam L.; Cannister, Matthew; Johansen, Rebecca; Estes, L. Dwayne; Hamilton, Steven W.; Barrass, Andrew N.

    2013-01-01

    The Nonindigenous Aquatic Species (NAS) database (http://nas.er.usgs.gov) functions as a national repository and clearinghouse for occurrence data for introduced species within the United States. Included is locality information on over 1,100 species of vertebrates, invertebrates, and vascular plants introduced as early as 1850. Taxa include foreign (exotic) species and species native to North America that have been transported outside of their natural range. Locality data are obtained from published and unpublished literature, state, federal and local monitoring programs, museum accessions, on-line databases, websites, professional communications and on-line reporting forms. The NAS web site provides immediate access to new occurrence records through a real-time interface with the NAS database. Visitors to the web site are presented with a set of pre-defined queries that generate lists of species according to state or hydrologic basin of interest. Fact sheets, distribution maps, and information on new occurrences are updated as new records and information become available. The NAS database allows resource managers to learn of new introductions reported in their region or nearby regions, improving response time. Conversely, managers are encouraged to report their observations of new occurrences to the NAS database so information can be disseminated to other managers, researchers, and the public. In May 2004, the NAS database incorporated an Alert System to notify registered users of new introductions as part of a national early detection/rapid response system. Users can register to receive alerts based on geographic or taxonomic criteria. The NAS database was used to identify 23 fish species introduced into the lower Tennessee and Cumberland drainages. Most of these are sport fish stocked to support fisheries, but the list also includes accidental and illegal introductions such as Asian Carps, clupeids, various species popular in the aquarium trade, and Atlantic

  8. Diel flight behaviour and dispersal patterns of aquatic Coleoptera and Heteroptera species with special emphasis on the importance of seasons.

    PubMed

    Csabai, Zoltán; Kálmán, Zoltán; Szivák, Ildikó; Boda, Pál

    2012-09-01

    Dispersal flight is the most important and almost the only way for primary aquatic insects to find new water habitats. During a 30-week-long project, we monitored the flight dispersal behaviour of aquatic beetles and bugs with using highly and horizontally polarizing agricultural black plastic sheets laid onto the ground. Based on the flight data of more than 45,000 individuals and 92 species, we explored and described eight different diel flight activity patterns. We found that seven of eight dispersal patterns are consistent with the previous knowledge, while three conspicuous mass dispersal periods can be identified as in the mid morning and/or around noon and/or at nightfall. As an exception, we found a 'daytime' pattern occurred exclusively in spring, in which mass dispersal can be seen from mid morning to late afternoon. In contrast to previous studies, we emphasize here that the seasonality has to be considered in evaluation of the diurnal flight activity. According to the seasons, a 'three code sign' was proposed to indicate the diel dispersal flight behaviour of a species for a year. Most of the species utilize different diel activity patterns in different seasons. In spring, the daytime pattern was the preferred type, but in summer and autumn, the evening types were the most popular patterns. We stated that the seasonal change of air temperature has a crucial role in that a pattern could be manifested in a given season or not and brings a need to change the diel dispersal pattern among seasons.

  9. Diel flight behaviour and dispersal patterns of aquatic Coleoptera and Heteroptera species with special emphasis on the importance of seasons

    NASA Astrophysics Data System (ADS)

    Csabai, Zoltán; Kálmán, Zoltán; Szivák, Ildikó; Boda, Pál

    2012-09-01

    Dispersal flight is the most important and almost the only way for primary aquatic insects to find new water habitats. During a 30-week-long project, we monitored the flight dispersal behaviour of aquatic beetles and bugs with using highly and horizontally polarizing agricultural black plastic sheets laid onto the ground. Based on the flight data of more than 45,000 individuals and 92 species, we explored and described eight different diel flight activity patterns. We found that seven of eight dispersal patterns are consistent with the previous knowledge, while three conspicuous mass dispersal periods can be identified as in the mid morning and/or around noon and/or at nightfall. As an exception, we found a `daytime' pattern occurred exclusively in spring, in which mass dispersal can be seen from mid morning to late afternoon. In contrast to previous studies, we emphasize here that the seasonality has to be considered in evaluation of the diurnal flight activity. According to the seasons, a `three code sign' was proposed to indicate the diel dispersal flight behaviour of a species for a year. Most of the species utilize different diel activity patterns in different seasons. In spring, the daytime pattern was the preferred type, but in summer and autumn, the evening types were the most popular patterns. We stated that the seasonal change of air temperature has a crucial role in that a pattern could be manifested in a given season or not and brings a need to change the diel dispersal pattern among seasons.

  10. Diel flight behaviour and dispersal patterns of aquatic Coleoptera and Heteroptera species with special emphasis on the importance of seasons.

    PubMed

    Csabai, Zoltán; Kálmán, Zoltán; Szivák, Ildikó; Boda, Pál

    2012-09-01

    Dispersal flight is the most important and almost the only way for primary aquatic insects to find new water habitats. During a 30-week-long project, we monitored the flight dispersal behaviour of aquatic beetles and bugs with using highly and horizontally polarizing agricultural black plastic sheets laid onto the ground. Based on the flight data of more than 45,000 individuals and 92 species, we explored and described eight different diel flight activity patterns. We found that seven of eight dispersal patterns are consistent with the previous knowledge, while three conspicuous mass dispersal periods can be identified as in the mid morning and/or around noon and/or at nightfall. As an exception, we found a 'daytime' pattern occurred exclusively in spring, in which mass dispersal can be seen from mid morning to late afternoon. In contrast to previous studies, we emphasize here that the seasonality has to be considered in evaluation of the diurnal flight activity. According to the seasons, a 'three code sign' was proposed to indicate the diel dispersal flight behaviour of a species for a year. Most of the species utilize different diel activity patterns in different seasons. In spring, the daytime pattern was the preferred type, but in summer and autumn, the evening types were the most popular patterns. We stated that the seasonal change of air temperature has a crucial role in that a pattern could be manifested in a given season or not and brings a need to change the diel dispersal pattern among seasons. PMID:22899422

  11. Nuclear microscopy as a tool in TiO2 nanoparticles bioaccumulation studies in aquatic species

    NASA Astrophysics Data System (ADS)

    Pinheiro, Teresa; Moita, Liliana; Silva, Luís; Mendonça, Elsa; Picado, Ana

    2013-07-01

    Engineered Titanium nanoparticles are used for a wide range of applications from coatings, sunscreen cosmetic additives to solar cells or water treatment agents. Inevitably environmental exposure can be expected and data on the ecotoxicological evaluation of nanoparticles are still scarce. The potential effects of nanoparticles of titanium dioxide (TiO2) on two model organisms, the water flea, Daphnia magna and the duckweed Lemna minor, were examined in semichronic toxicity tests. Daphnia and Lemna were exposed to TiO2 nanoparticles (average particle size value of 28 ± 11 nm (n = 42); concentration range, 1.4-25 mg/L) by dietary route and growth in medium containing the nanoparticles of TiO2, respectively. Both morphology and microdistribution of Ti in the individuals were examined by nuclear microscopy techniques. A significant amount of TiO2 was found accumulated in Daphnia exposed to nanoparticles. Nuclear microscopy imaging revealed that Ti was localized only in the digestive tract of the Daphnia, which displayed difficulty in eliminating the nanoparticles from their body. Daphnia showed higher mortality when exposed to higher concentrations of TiO2 (>10 mg/L). The exposure to TiO2 nanoparticles above 25 mg/L caused morphological alterations in Lemna. The roots became stiff and fronds colorless. The Ti mapping of cross-sections of roots and fronds showed that Ti was mainly deposited in the epidermis of the fronds and roots, with minor internalization. In summary, exposure of aquatic organisms to TiO2 nanoparticles may alter the physiology of these organisms at individual and population levels, posing risks to aquatic ecosystems.

  12. A numerical taxonomic study of species of Vibrio isolated from the aquatic environment and birds in Kent, England.

    PubMed

    West, P A; Lee, J V; Bryant, T N

    1983-10-01

    A numerical taxonomic study has been carried out to confirm the identity of strains of the family Vibrionaceae isolated during an ecological study. A total of 237 strains were studied including 148 from the aquatic environment, 6 from estuarine birds, 1 from sheep faeces, and 61 control cultures. Duplicates of 21 of the strains were randomly selected and included to estimate test and operator error. Taxonomic resemblance was estimated on the basis of 148 characters using Euclidean distance. The taxonomic position of some strains was reevaluated using the pattern different coefficient. Strains were clustered by three methods, all of which gave similar results. The estimated average probability of test error was 1.5%. Strains previously identified as Vibrio anguillarum fell into four distinct phenons corresponding to V. anguillarum biovar I, 'V. anguillarum biovar II', V. diazotrophicus, and strains pathogenic to oyster larvae. The latter group characteristically degraded xanthine and probably represents a new species. The phenon corresponding to V. cholerae included the type strain, strains of human origin, and strains isolated in the United Kingdom from birds and the aquatic environment. Some strains of V. cholerae were luminous. Other phenons were identified as V. metschnikovii, V. fluvialis, and Aeromonas spp.

  13. The adaptational strategies of the hindlimb muscles in the Tenrecidae species including the aquatic web-footed tenrec (Limnogale mergulus).

    PubMed

    Endo, Hideki; Yonezawa, Takahiro; Rakotondraparany, Felix; Sasaki, Motoki; Hasegawa, Masami

    2006-07-01

    The hindlimb muscles in four species of Tenrecidae (Oryzoryctinae: Talazac long-tailed tenrec and web-footed tenrec, Tenrecinae: lesser hedgehog tenrec, and streaked tenrec), were examined macroscopically. The weight ratios of the muscles to the body in the oryzoryctinid species are larger than those in Tenrecinae, since the Oryzoryctinae species have an obviously smaller body from the evolutionary point of view. It can be primarily pointed out that the adaptation of the body size is different between the two subfamilies, and secondarily, that functional adaptation to locomotion is complete within each subfamily. The weight data and the morphological findings demonstrate that the web-footed tenrec possesses an extraordinary large M. semimembranosus in comparison to the Talazac long-tailed tenrec in their weight ratios. This muscle may act as a strong flexor motor in the knee joint during the aquatic locomotion of the web-footed tenrec. Since the other muscles of the web-footed tenrec are similar to those of the Talazac long-tailed tenrec regards weight ratio data, we think that the web-footed tenrec may have derived from a terrestrial ancestor such as the long-tailed tenrecs. In Tenrecinae the streaked tenrec is equipped with larger Mm. adductores, M. semimembranosus and M. triceps surae than the lesser hedgehog tenrec. This species is adapted to fossorial life derived from non-specialized ancestors within the evolutionary lines of the spiny tenrecs.

  14. Adapted Aquatics Programming: A Professional Guide.

    ERIC Educational Resources Information Center

    Lepore, Monica; Gayle, G. William; Stevens, Shawn F.

    This book is designed to help aquatic instructors in meeting the needs of individuals with disabilities in general or adapted aquatics programs. Part 1, "Foundations of Adapted Aquatics," introduces various philosophies and issues having to do with initiating adapted aquatics programs. Chapters address the benefits of aquatic activity, models for…

  15. [Ecological risk assessment of hydropower dam construction on aquatic species in middle reaches of Lancang River, Southwest China based on ESHIPPO model].

    PubMed

    Li, Xiao-Yan; Peng, Ming-Chun; Dong, Shi-Kui; Liu, Shi-Liang; Li, Jin-Peng; Yang, Zhi-Feng

    2013-02-01

    An investigation was conducted on the phytoplankton, zooplankton, and fish at 8 sampling sections in the Manwan Reservoir before and after the construction of Xiaowan Hydropower Dam. The modified ESHIPPO model was applied to study the changes of the featured aquatic species, including endangered species, endemic specie, peis resource species, and native fish, aimed to make an ecological risk assessment of the dam construction on the aquatic species. The dam construction had definite ecological risk on the aquatic species, especially the endemic fish, in Langcang River, due to the changes of hydrological conditions. The endemic species including Bangia atropurpurea, Lemanea sinica, Prasiola sp., Attheyella yunnanensis, and Neutrodiaptomus mariadvigae were at high ecological risk, and thus, besides monitoring, protection measures were needed to be taken to lower the possibility of the species extinction. The widely distributed species of phytoplankton and zooplankton were at medium ecological risk, and protection measures besides monitoring should be prepared. Twelve kinds of native fish, including Barbodes huangchuchieni, Sinilabeo laticeps, Racoma lantsangensis, Racoma lissolabiatus, Paracobitis anguillioides, Schistura latifasciata, Botia nigrolineata, Vanmanenia striata, Homaloptera yunnanensis, Platytropius longianlis, Glyptothorax zanaensis, and Pseudecheneis immaculate, were at high ecological risk, and protection measures needed to be developed to prevent the possibility of the species loss and extinction.

  16. Development of aquatic toxicity benchmarks for oil products using species sensitivity distributions

    EPA Science Inventory

    Determining the sensitivity of a diversity of species to spilled oil and chemically dispersed oil continues to be a significant challenge in spill response and impact assessment. We used standardized tests from the literature to develop species sensitivity distributions (SSDs) of...

  17. 78 FR 77705 - Proposed Agency Information Collection Activity: Nonindigenous Aquatic Species Sighting Reporting...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-12-24

    ... ecosystems, and human and wildlife health. These invaders extract a huge cost, an estimated 120 billion... health-related costs of invasive species exceed those of all other natural disasters combined. Through... important role in federal efforts to combat invasive species in natural and semi-natural areas through...

  18. Keystone predators (eastern newts, Notophthalmus viridescens) reduce the impacts of an aquatic invasive species

    USGS Publications Warehouse

    Smith, Kimberly G.

    2006-01-01

    Predation, competition, and their interaction are known to be important factors that influence the structure of ecological communities. In particular, in those cases where a competitive hierarchy exists among prey species, the presence of certain keystone predators can result in enhanced diversity in the prey community. However, little is known regarding the influence of keystone predator presence on invaded prey communities. Given the widespread occurrence of invasive species and substantial concern regarding their ecological impacts, studies on this topic are needed. In this study I used naturalistic replications of an experimental tadpole assemblage to assess the influence of predatory eastern newts, Notophthalmus viridescens, on the outcome of interspecific competition among native and nonindigenous tadpoles. When newts were absent, the presence of the tadpoles of one invasive species, the Cuban treefrog, Osteopilus septentrionalis, resulted in decreased survival and growth rate of the dominant native species, Bufo terrestris, and dominance of the tadpole assemblage by O. septentrionalis. However, the presence of one adult newt generally reduced or eliminated the negative impacts of O. septentrionalis tadpoles, resulting in comparable survival and performance of native species in invaded and noninvaded treatments. Differential mortality among the tadpole species suggests that newts preyed selectively on O. septentrionalis tadpoles, supporting the hypothesis that newts acted as keystone predators in the invaded assemblage. The presence of nonindigenous larval cane toads, Bufo marinus, did not significantly affect native species, and this species was not negatively affected by the presence of newts. Collectively, these results suggest that eastern newts significantly modified the competitive hierarchy of the invaded tadpole assemblage and reduced the impacts of a competitively superior invasive species. If general, these results suggest that the presence of

  19. Keystone predators (eastern newts, Notophthalmus viridescens) reduce the impacts of an aquatic invasive species.

    PubMed

    Smith, Kevin G

    2006-06-01

    Predation, competition, and their interaction are known to be important factors that influence the structure of ecological communities. In particular, in those cases where a competitive hierarchy exists among prey species, the presence of certain keystone predators can result in enhanced diversity in the prey community. However, little is known regarding the influence of keystone predator presence on invaded prey communities. Given the widespread occurrence of invasive species and substantial concern regarding their ecological impacts, studies on this topic are needed. In this study I used naturalistic replications of an experimental tadpole assemblage to assess the influence of predatory eastern newts, Notophthalmus viridescens, on the outcome of interspecific competition among native and nonindigenous tadpoles. When newts were absent, the presence of the tadpoles of one invasive species, the Cuban treefrog, Osteopilus septentrionalis, resulted in decreased survival and growth rate of the dominant native species, Bufo terrestris, and dominance of the tadpole assemblage by O. septentrionalis. However, the presence of one adult newt generally reduced or eliminated the negative impacts of O. septentrionalis tadpoles, resulting in comparable survival and performance of native species in invaded and noninvaded treatments. Differential mortality among the tadpole species suggests that newts preyed selectively on O. septentrionalis tadpoles, supporting the hypothesis that newts acted as keystone predators in the invaded assemblage. The presence of nonindigenous larval cane toads, Bufo marinus, did not significantly affect native species, and this species was not negatively affected by the presence of newts. Collectively, these results suggest that eastern newts significantly modified the competitive hierarchy of the invaded tadpole assemblage and reduced the impacts of a competitively superior invasive species. If general, these results suggest that the presence of

  20. Assessing contaminant sensitivity of endangered and threatened aquatic species: Part III. Effluent toxicity tests

    USGS Publications Warehouse

    Dwyer, F.J.; Hardesty, D.K.; Henke, C.E.; Ingersoll, C.G.; Whites, D.W.; Augspurger, T.; Canfield, T.J.; Mount, D.R.; Mayer, F.L.

    2005-01-01

    Toxicity tests using standard effluent test procedures described by the U.S. Environmental Protection Agency were conducted with Ceriodaphnia dubia, fathead minnows (Pimephales promelas), and seven threatened and endangered (listed) fish species from four families: (1) Acipenseridae: shortnose sturgeon (Acipenser brevirostrum); (2) Catostomidae; razorback sucker (Xyrauchen texanus); (3) Cyprinidae: bonytail chub (Gila elegans), Cape Fear shiner (Notropis mekistocholas) Colorado pikeminnow (Ptychocheilus lucius), and spotfin chub (Cyprinella monacha); and (4) Poecillidae: Gila topminnow (Poeciliopsis occidentalis). We conducted 7-day survival and growth studies with embryo-larval fathead minnows and analogous exposures using the listed species. Survival and reproduction were also determined with C. dubia. Tests were conducted with carbaryl, ammonia-or a simulated effluent complex mixture of carbaryl, copper, 4-nonylphenol, pentachlorophenol and permethrin at equitoxic proportions. In addition, Cape Fear shiners and spotfin chub were tested using diazinon, copper, and chlorine. Toxicity tests were also conducted with field-collected effluents from domestic or industrial facilities. Bonytail chub and razorback suckers were tested with effluents collected in Arizona whereas effluent samples collected from North Carolina were tested with Cape Fear shiner, spotfin chub, and shortnose sturgeon. The fathead minnow 7-day effluent test was often a reliable estimator of toxic effects to the listed fishes. However, in 21 % of the tests, a listed species was more sensitive than fathead minnows. More sensitive species results varied by test so that usually no species was always more or less sensitive than fathead minnows. Only the Gila topminnow was consistently less sensitive than the fathead minnow. Listed fish species were protected 96% of the time when results for both fathead minnows and C. dubia were considered, thus reinforcing the value of standard whole

  1. Body Size Is a Significant Predictor of Congruency in Species Richness Patterns: A Meta-Analysis of Aquatic Studies

    PubMed Central

    Velghe, Katherine; Gregory-Eaves, Irene

    2013-01-01

    Biodiversity losses over the next century are predicted to result in alterations of ecosystem functions that are on par with other major drivers of global change. Given the seriousness of this issue, there is a need to effectively monitor global biodiversity. Because performing biodiversity censuses of all taxonomic groups is prohibitively costly, indicator groups have been studied to estimate the biodiversity of different taxonomic groups. Quantifying cross-taxon congruence is a method of evaluating the assumption that the diversity of one taxonomic group can be used to predict the diversity of another. To improve the predictive ability of cross-taxon congruence in aquatic ecosystems, we evaluated whether body size, measured as the ratio of average body length between organismal groups, is a significant predictor of their cross-taxon biodiversity congruence. To test this hypothesis, we searched the published literature and screened for studies that used species richness correlations as their metric of cross-taxon congruence. We extracted 96 correlation coefficients from 16 studies, which encompassed 784 inland water bodies. With these correlation coefficients, we conducted a categorical meta-analysis, grouping data based on the body size ratio of organisms. Our results showed that cross-taxon congruence is variable among sites and between different groups (r values ranging between −0.53 to 0.88). In addition, our quantitative meta-analysis demonstrated that organisms most similar in body size showed stronger species richness correlations than organisms which differed increasingly in size (radj2 = 0.94, p = 0.02). We propose that future studies applying biodiversity indicators in aquatic ecosystems consider functional traits such as body size, so as to increase their success at predicting the biodiversity of taxonomic groups where cost-effective conservation tools are needed. PMID:23468903

  2. Aquatic toxicity variability for fresh- and saltwater species in refinery wastewater effluent

    SciTech Connect

    Bleckmann, C.A.; Rabe, B.; Edgmon, S.J.; Fillingame, D.

    1995-07-01

    The US Environmental Protection Agency (EPA) has established test requirements for toxicity reduction or toxicity identification evaluations (TR/TIE) of wastewater effluents. Interpretations of test results are complicated by factors other than toxicity when essentially freshwater wastewaters flow into estuaries and the effluent permit requires marine organisms for testing. This paper reports the results of an investigation of potential freshwater surrogate species, and Microtox{reg_sign}, for use in such a TIE. Of the five species tested, mysid shrimp were found to be most sensitive to unidentified toxicants in petroleum refinery wastewater. No strong correlations of this sensitivity to that of other organisms, or to several wastewater constitutents, were identified. The two marine species specified in the effluent permit were more sensitive to the toxicants that were the freshwater species.

  3. DEVELOPMENT OF DNA-BASED TOOLS FOR IDENTIFICATION AND MONITORING OF AQUATIC INTRODUCED SPECIES

    EPA Science Inventory

    Claims for potential applications of DNA taxonomy range from identification of unknown specimens and the discovery of new species to the study of biodiversity through comprehensive characterizations of complex biotic communities drawn from environmental samples. Recently, these a...

  4. Aquatic Activities for Youth.

    ERIC Educational Resources Information Center

    Greene, H. David; And Others

    Designed to meet the diverse educational needs of youth groups, this aquatic program consists of eight individual lesson units, each devoted to one aspect of the aquatic world. Unit topics include: fish aquariums; raising earthworms; simulation of coastal planning; entomology and water; rope; calculating stream flow; saltwater aquariums; and fish…

  5. Risk assessment and toxic effects of metal pollution in two cultured and wild fish species from highly degraded aquatic habitats.

    PubMed

    Omar, Wael A; Zaghloul, Khalid H; Abdel-Khalek, Amr A; Abo-Hegab, S

    2013-11-01

    Lake Qaroun is an inland lake at the lowest part of El-Fayoum depression, Egypt. It receives agricultural and domestic non-treated drainage waters, which are also used for aquaculture in Qaroun area. The results of the present study aimed to provide comparable data between wild (collected from Lake Qaroun) and cultured (collected from Qaroun fish farms and the reference site) Nile tilapia Oreochromis niloticus and mullet Mugil cephalus, as indicators of natural and anthropogenic impacts on aquatic ecosystem as well as to evaluate the human hazard index associated with fish consumption. Metal concentrations in fish tissues showed a species-specific bioaccumulation pattern. Statistically significant differences were observed in the mean metal concentrations with lower bioavailability in M. cephalus compared with O. niloticus in internal vital organs (liver, kidney, and muscle) but much higher in external organs (gill and skin). Histopathological alterations and evident damages were observed in gill, liver, and kidney of both species collected from Lake Qaroun and Qaroun fish farms compared with those from the reference site. The results showed significant increase of plasma aspartate aminotransferase and alanine aminotransferase activity as well as creatinine and uric acid concentration in both fish species from polluted locations. The human health hazard index showed that the cumulative risk greatly increases with increasing fish consumption rate, thus yielding an alarming concern for consumer health.

  6. Elucidating the Diversity of Aquatic Microdochium and Trichoderma Species and Their Activity against the Fish Pathogen Saprolegnia diclina

    PubMed Central

    Liu, Yiying; Zachow, Christin; Raaijmakers, Jos M.; de Bruijn, Irene

    2016-01-01

    Animals and plants are increasingly threatened by emerging fungal and oomycete diseases. Amongst oomycetes, Saprolegnia species cause population declines in aquatic animals, especially fish and amphibians, resulting in significant perturbation in biodiversity, ecological balance and food security. Due to the prohibition of several chemical control agents, novel sustainable measures are required to control Saprolegnia infections in aquaculture. Previously, fungal community analysis by terminal restriction fragment length polymorphism (T-RFLP) revealed that the Ascomycota, specifically the genus Microdochium, was an abundant fungal phylum associated with salmon eggs from a commercial fish farm. Here, phylogenetic analyses showed that most fungal isolates obtained from salmon eggs were closely related to Microdochium lycopodinum/Microdochium phragmitis and Trichoderma viride species. Phylogenetic and quantitative PCR analyses showed both a quantitative and qualitative difference in Trichoderma population between diseased and healthy salmon eggs, which was not the case for the Microdochium population. In vitro antagonistic activity of the fungi against Saprolegnia diclina was isolate-dependent; for most Trichoderma isolates, the typical mycoparasitic coiling around and/or formation of papilla-like structures on S. diclina hyphae were observed. These results suggest that among the fungal community associated with salmon eggs, Trichoderma species may play a role in Saprolegnia suppression in aquaculture. PMID:26805821

  7. Elucidating the Diversity of Aquatic Microdochium and Trichoderma Species and Their Activity against the Fish Pathogen Saprolegnia diclina.

    PubMed

    Liu, Yiying; Zachow, Christin; Raaijmakers, Jos M; de Bruijn, Irene

    2016-01-01

    Animals and plants are increasingly threatened by emerging fungal and oomycete diseases. Amongst oomycetes, Saprolegnia species cause population declines in aquatic animals, especially fish and amphibians, resulting in significant perturbation in biodiversity, ecological balance and food security. Due to the prohibition of several chemical control agents, novel sustainable measures are required to control Saprolegnia infections in aquaculture. Previously, fungal community analysis by terminal restriction fragment length polymorphism (T-RFLP) revealed that the Ascomycota, specifically the genus Microdochium, was an abundant fungal phylum associated with salmon eggs from a commercial fish farm. Here, phylogenetic analyses showed that most fungal isolates obtained from salmon eggs were closely related to Microdochium lycopodinum/Microdochium phragmitis and Trichoderma viride species. Phylogenetic and quantitative PCR analyses showed both a quantitative and qualitative difference in Trichoderma population between diseased and healthy salmon eggs, which was not the case for the Microdochium population. In vitro antagonistic activity of the fungi against Saprolegnia diclina was isolate-dependent; for most Trichoderma isolates, the typical mycoparasitic coiling around and/or formation of papilla-like structures on S. diclina hyphae were observed. These results suggest that among the fungal community associated with salmon eggs, Trichoderma species may play a role in Saprolegnia suppression in aquaculture. PMID:26805821

  8. Elucidating the Diversity of Aquatic Microdochium and Trichoderma Species and Their Activity against the Fish Pathogen Saprolegnia diclina.

    PubMed

    Liu, Yiying; Zachow, Christin; Raaijmakers, Jos M; de Bruijn, Irene

    2016-01-21

    Animals and plants are increasingly threatened by emerging fungal and oomycete diseases. Amongst oomycetes, Saprolegnia species cause population declines in aquatic animals, especially fish and amphibians, resulting in significant perturbation in biodiversity, ecological balance and food security. Due to the prohibition of several chemical control agents, novel sustainable measures are required to control Saprolegnia infections in aquaculture. Previously, fungal community analysis by terminal restriction fragment length polymorphism (T-RFLP) revealed that the Ascomycota, specifically the genus Microdochium, was an abundant fungal phylum associated with salmon eggs from a commercial fish farm. Here, phylogenetic analyses showed that most fungal isolates obtained from salmon eggs were closely related to Microdochium lycopodinum/Microdochium phragmitis and Trichoderma viride species. Phylogenetic and quantitative PCR analyses showed both a quantitative and qualitative difference in Trichoderma population between diseased and healthy salmon eggs, which was not the case for the Microdochium population. In vitro antagonistic activity of the fungi against Saprolegnia diclina was isolate-dependent; for most Trichoderma isolates, the typical mycoparasitic coiling around and/or formation of papilla-like structures on S. diclina hyphae were observed. These results suggest that among the fungal community associated with salmon eggs, Trichoderma species may play a role in Saprolegnia suppression in aquaculture.

  9. Haemogregarine infections of three species of aquatic freshwater turtles from two sites in Costa Rica

    PubMed Central

    Rossow, John A.; Hernandez, Sonia M.; Sumner, Scarlett M.; Altman, Bridget R.; Crider, Caroline G.; Gammage, Mallory B.; Segal, Kristy M.; Yabsley, Michael J.

    2013-01-01

    Twenty-five black river turtles (Rhinoclemmys funerea) and eight white-lipped mud turtles (Kinosternon leucostomum) from Selva Verde, Costa Rica were examined for haemoparasites. Leeches identified as Placobdella multilineata were detected on individuals from both species. All turtles sampled were positive for intraerythrocytic haemogregarines (Apicomplexa:Adeleorina) and the average parasitemia of black river turtles (0.34% ± 0.07) was significantly higher compared to white-lipped mud turtles (0.05% ± 0.006). No correlation was found between parasitemia and relative body mass of either species or between black river turtles from the two habitats. In addition, one scorpion mud turtle (Kinosternon scorpioides) examined from La Pacifica, Costa Rica, was positive for haemogregarines (0.01% parasitemia). Interestingly, parasites of the scorpion mud turtle were significantly smaller than those from the other two species and did not displace the erythrocyte nucleus, whereas parasites from the other two species consistently displaced host cell nuclei and often distorted size and shape of erythrocytes. This is the first report of haemogregarines in turtles from Central America and of haemogregarines in K. leucostomum, K. scorpioides, and any Rhinoclemmys species. Additional studies are needed to better characterise and understand the ecology of these parasites. PMID:24533326

  10. New species and first records of trichomycetes from immature aquatic insects in Idaho.

    PubMed

    Bench, Molly E; White, Merlin M

    2012-01-01

    Trichomycetes, or gut fungi, are currently recognized as an ecological group of fungi and protists that inhabit the guts of immature insects or other stages and types of arthropods. The geographic distribution of these endosymbionts is worldwide. However trichomycete data from the Pacific Northwest are limited and this is the first account of gut fungi in Idaho. We report on the trichomycetes from a single site, Cottonwood Creek at Military Reserve Park, Boise, Idaho, where periodic surveys for more than a year resulted in the discovery of four newly named, three probably new but unnamed and 15 previously known species. Among the Harpellales three new species, Capniomyces sasquatchoides, Harpella torus and Lancisporomyces lampetriformis, are described, with two possibly new species of Smittium detailed but unnamed at this time pending further collections. A Genistelloides cf. hibernus also is included as a possible new species. One new species of Amoebidiales, Paramoebidium hamatum, is described as well. Hosts in which the gut fungi were recovered include larvae or nymphs of Diptera (Chironomidae and Simuliidae), Ephemeroptera (Baetidae) and Plecoptera (Capniidae and Taeniopterygidae). We hope to demonstrate that future surveys or bioprospecting investigations into the biodiversity of these early-diverging fungi in this region and worldwide remain promising.

  11. Metamorphosis of two amphibian species after chronic cadmium exposure in outdoor aquatic mesocosms

    USGS Publications Warehouse

    James, S.M.; Little, E.E.; Semlitsch, R.D.

    2005-01-01

    Amphibian larvae at contaminated sites may experience an alteration of metamorphic traits and survival compared to amphibians in uncontaminated conditions. Effects of chronic cadmium (Cd) exposure on the metamorphosis of American toads (Bufo americanus) and southern leopard frogs (Rana sphenocephala) were determined. The two species were reared separately from shortly after hatching through metamorphosis in outdoor mesocosms (1,325-L polyethylene cattle tanks) that simulated natural ponds and enhanced environmental realism relative to the laboratory. Both species exhibited a decrease in survival with increasing initial nominal aqueous Cd concentration. Cadmium treatment did not influence mass at metamorphosis for either species when survival was included as a covariate, but increased the age at metamorphosis for the American toads. The whole body Cd content of metamorphs increased with aqueous Cd treatment level for both species, and the American toads tended to possess more elevated residues. Cadmium quickly partitioned out of the water column and accumulated in and altered the abundance of the tadpoles' diet. Cadmium-contaminated sites may produce fewer metamorphs, and those that survive will metamorphose later and contain Cd. Interspecific differences in the response variables illustrate the importance of testing multiple species when assessing risk. ?? 2005 SETAC.

  12. Toxicity testing of herbicide norflurazon on an aquatic bioindicator species--the planarian Polycelis felina (Daly.).

    PubMed

    Horvat, T; Kalafatić, M; Kopjar, N; Kovacević, G

    2005-07-30

    Norflurazon is a bleaching, preemergence herbicide. Due to its mobility and long half-life it presents a potential for groundwater contamination. The aim of our study was to investigate toxic effects of norflurazon on non-targeted aquatic bioindicator organism, the planarian Polycelis felina (Daly.). Animals were exposed to water solutions of norflurazon in concentrations 200, 20, 2 and 0.2 microM. Mortality, locomotive and morphological changes were monitored. Histological changes were studied both on treated and control animals with light microscopy. The primary DNA damage on single planarian cells was studied using the alkaline comet assay. Three comet parameters were studied: tail length, percentage of DNA in comet tail and tail moment. The results showed that norflurazon caused mortality, locomotive, morphological and histological changes in treated animals compared to corresponding controls. The most prominent histological changes were damage of the outer mucous layer, lack of rhabdites, damage to epidermis and extensive damage to parenchyma cells. The results of alkaline comet assay indicated that norflurazon in concentrations of 2 and 0.2 microM induces significant increase of primary DNA damage in planarian cells compared to the corresponding control animals. The mean values of all three measured parameters were significantly elevated on the fourth day of the treatment compared with the first and the seventh day. Based on the results of mortality and locomotive observations, we conclude that the fourth day of the treatment represents a certain threshold within planarian metabolism followed by the beginning of detoxification and recovery. However, histological preparations and comet data statistics show results indicating that high toxicity on the seventh day of the treatment gave the results of decrease of DNA damage due to the tissue/cell damage (apoptosis) and not recovery. The present study showed the ability of norflurazon to induce a wide range of

  13. Genetic diversity in three invasive clonal aquatic species in New Zealand

    PubMed Central

    2010-01-01

    Background Elodea canadensis, Egeria densa and Lagarosiphon major are dioecious clonal species which are invasive in New Zealand and other regions. Unlike many other invasive species, the genetic variation in New Zealand is very limited. Clonal reproduction is often considered an evolutionary dead end, even though a certain amount of genetic divergence may arise due to somatic mutations. The successful growth and establishment of invasive clonal species may be explained not by adaptability but by pre-existing ecological traits that prove advantageous in the new environment. We studied the genetic diversity and population structure in the North Island of New Zealand using AFLPs and related the findings to the number of introductions and the evolution that has occurred in the introduced area. Results Low levels of genetic diversity were found in all three species and appeared to be due to highly homogeneous founding gene pools. Elodea canadensis was introduced in 1868, and its populations showed more genetic structure than those of the more recently introduced of E. densa (1946) and L. major (1950). Elodea canadensis and L. major, however, had similar phylogeographic patterns, in spite of the difference in time since introduction. Conclusions The presence of a certain level of geographically correlated genetic structure in the absence of sexual reproduction, and in spite of random human dispersal of vegetative propagules, can be reasonably attributed to post-dispersal somatic mutations. Direct evidence of such evolutionary events is, however, still insufficient. PMID:20565861

  14. Aquatic invasive species early detection in the Great Lakes: Lessons concerning strategy

    EPA Science Inventory

    Great Lakes coastal systems are vulnerable to introduction of a wide variety of non-indigenous species (NIS), and the desire to effectively respond to future invaders is prompting efforts towards establishing a broad early-detection network. Such a network requires statistically...

  15. Developing strategies for aquatic invasive species early detection in the Great Lakes

    EPA Science Inventory

    As part of a webinar round-table discussion of invasive species and ballast water research, Dr. Trebitz will be giving a short overview of the research that she and co-PIs Jack Kelly, Joel Hoffman, and Greg Peterson are conducting in this area. Key findings from the 2005-2007 sam...

  16. IDENTIFYING SOURCES OF STRESS TO NATIVE AQUATIC SPECIES USING A WATERSHED ECOLOGICAL RISK ASSESSMENT FRAMEWORK.

    EPA Science Inventory

    The free-flowing Clinch and Powell River basin, located in southwestern Virginia, U.S.A., historically had one of the richest assemblages of native fish and freshwater mussels in the world. Nearly half of the species once residing here are now extinct, threatened or endangered....

  17. Progress towards design elements for a Great Lakes-wide aquatic invasive species early detection network

    EPA Science Inventory

    Great Lakes coastal systems are vulnerable to introduction of a wide variety of non-indigenous species (NIS), and the desire to effectively respond to future invaders is prompting efforts towards establishing a broad early-detection network. Such a network requires statistically...

  18. Predicting fine-scale distributions of peripheral aquatic species in headwater streams

    SciTech Connect

    DeRolph, Christopher R.; Nelson, Stacy A. C.; Kwak, Thomas J.; Hain, Ernie F.

    2014-12-09

    Headwater species and peripheral populations that occupy habitat at the edge of a species range may hold an increased conservation value to managers due to their potential to maximize intraspecies diversity and species' adaptive capabilities in the context of rapid environmental change. The southern Appalachian Mountains are the southern extent of the geographic range of native Salvelinus fontinalis and naturalized Oncorhynchus mykiss and Salmo trutta in eastern North America. In this paper, we predicted distributions of these peripheral, headwater wild trout populations at a fine scale to serve as a planning and management tool for resource managers to maximize resistance and resilience of these populations in the face of anthropogenic stressors. We developed correlative logistic regression models to predict occurrence of brook trout, rainbow trout, and brown trout for every interconfluence stream reach in the study area. A stream network was generated to capture a more consistent representation of headwater streams. Each of the final models had four significant metrics in common: stream order, fragmentation, precipitation, and land cover. Strahler stream order was found to be the most influential variable in two of the three final models and the second most influential variable in the other model. Greater than 70% presence accuracy was achieved for all three models. The underrepresentation of headwater streams in commonly used hydrography datasets is an important consideration that warrants close examination when forecasting headwater species distributions and range estimates. Finally and additionally, it appears that a relative watershed position metric (e.g., stream order) is an important surrogate variable (even when elevation is included) for biotic interactions across the landscape in areas where headwater species distributions are influenced by topographical gradients.

  19. Predicting fine-scale distributions of peripheral aquatic species in headwater streams.

    PubMed

    DeRolph, Christopher R; Nelson, Stacy A C; Kwak, Thomas J; Hain, Ernie F

    2015-01-01

    Headwater species and peripheral populations that occupy habitat at the edge of a species range may hold an increased conservation value to managers due to their potential to maximize intraspecies diversity and species' adaptive capabilities in the context of rapid environmental change. The southern Appalachian Mountains are the southern extent of the geographic range of native Salvelinus fontinalis and naturalized Oncorhynchus mykiss and Salmo trutta in eastern North America. We predicted distributions of these peripheral, headwater wild trout populations at a fine scale to serve as a planning and management tool for resource managers to maximize resistance and resilience of these populations in the face of anthropogenic stressors. We developed correlative logistic regression models to predict occurrence of brook trout, rainbow trout, and brown trout for every interconfluence stream reach in the study area. A stream network was generated to capture a more consistent representation of headwater streams. Each of the final models had four significant metrics in common: stream order, fragmentation, precipitation, and land cover. Strahler stream order was found to be the most influential variable in two of the three final models and the second most influential variable in the other model. Greater than 70% presence accuracy was achieved for all three models. The underrepresentation of headwater streams in commonly used hydrography datasets is an important consideration that warrants close examination when forecasting headwater species distributions and range estimates. Additionally, it appears that a relative watershed position metric (e.g., stream order) is an important surrogate variable (even when elevation is included) for biotic interactions across the landscape in areas where headwater species distributions are influenced by topographical gradients. PMID:25628872

  20. Predicting fine-scale distributions of peripheral aquatic species in headwater streams

    PubMed Central

    DeRolph, Christopher R; Nelson, Stacy A C; Kwak, Thomas J; Hain, Ernie F

    2015-01-01

    Headwater species and peripheral populations that occupy habitat at the edge of a species range may hold an increased conservation value to managers due to their potential to maximize intraspecies diversity and species' adaptive capabilities in the context of rapid environmental change. The southern Appalachian Mountains are the southern extent of the geographic range of native Salvelinus fontinalis and naturalized Oncorhynchus mykiss and Salmo trutta in eastern North America. We predicted distributions of these peripheral, headwater wild trout populations at a fine scale to serve as a planning and management tool for resource managers to maximize resistance and resilience of these populations in the face of anthropogenic stressors. We developed correlative logistic regression models to predict occurrence of brook trout, rainbow trout, and brown trout for every interconfluence stream reach in the study area. A stream network was generated to capture a more consistent representation of headwater streams. Each of the final models had four significant metrics in common: stream order, fragmentation, precipitation, and land cover. Strahler stream order was found to be the most influential variable in two of the three final models and the second most influential variable in the other model. Greater than 70% presence accuracy was achieved for all three models. The underrepresentation of headwater streams in commonly used hydrography datasets is an important consideration that warrants close examination when forecasting headwater species distributions and range estimates. Additionally, it appears that a relative watershed position metric (e.g., stream order) is an important surrogate variable (even when elevation is included) for biotic interactions across the landscape in areas where headwater species distributions are influenced by topographical gradients. PMID:25628872

  1. Predicting fine-scale distributions of peripheral aquatic species in headwater streams

    DOE PAGES

    DeRolph, Christopher R.; Nelson, Stacy A. C.; Kwak, Thomas J.; Hain, Ernie F.

    2014-12-09

    Headwater species and peripheral populations that occupy habitat at the edge of a species range may hold an increased conservation value to managers due to their potential to maximize intraspecies diversity and species' adaptive capabilities in the context of rapid environmental change. The southern Appalachian Mountains are the southern extent of the geographic range of native Salvelinus fontinalis and naturalized Oncorhynchus mykiss and Salmo trutta in eastern North America. In this paper, we predicted distributions of these peripheral, headwater wild trout populations at a fine scale to serve as a planning and management tool for resource managers to maximize resistancemore » and resilience of these populations in the face of anthropogenic stressors. We developed correlative logistic regression models to predict occurrence of brook trout, rainbow trout, and brown trout for every interconfluence stream reach in the study area. A stream network was generated to capture a more consistent representation of headwater streams. Each of the final models had four significant metrics in common: stream order, fragmentation, precipitation, and land cover. Strahler stream order was found to be the most influential variable in two of the three final models and the second most influential variable in the other model. Greater than 70% presence accuracy was achieved for all three models. The underrepresentation of headwater streams in commonly used hydrography datasets is an important consideration that warrants close examination when forecasting headwater species distributions and range estimates. Finally and additionally, it appears that a relative watershed position metric (e.g., stream order) is an important surrogate variable (even when elevation is included) for biotic interactions across the landscape in areas where headwater species distributions are influenced by topographical gradients.« less

  2. Predicting fine-scale distributions of peripheral aquatic species in headwater streams

    USGS Publications Warehouse

    DeRolph, Christopher R.; Nelson, S.; Kwak, Thomas J.; Hain, Ernie F.

    2015-01-01

    Headwater species and peripheral populations that occupy habitat at the edge of a species range may hold an increased conservation value to managers due to their potential to maximize intraspecies diversity and species' adaptive capabilities in the context of rapid environmental change. The southern Appalachian Mountains are the southern extent of the geographic range of native Salvelinus fontinalis and naturalized Oncorhynchus mykiss and Salmo trutta in eastern North America. We predicted distributions of these peripheral, headwater wild trout populations at a fine scale to serve as a planning and management tool for resource managers to maximize resistance and resilience of these populations in the face of anthropogenic stressors. We developed correlative logistic regression models to predict occurrence of brook trout, rainbow trout, and brown trout for every interconfluence stream reach in the study area. A stream network was generated to capture a more consistent representation of headwater streams. Each of the final models had four significant metrics in common: stream order, fragmentation, precipitation, and land cover. Strahler stream order was found to be the most influential variable in two of the three final models and the second most influential variable in the other model. Greater than 70% presence accuracy was achieved for all three models. The underrepresentation of headwater streams in commonly used hydrography datasets is an important consideration that warrants close examination when forecasting headwater species distributions and range estimates. Additionally, it appears that a relative watershed position metric (e.g., stream order) is an important surrogate variable (even when elevation is included) for biotic interactions across the landscape in areas where headwater species distributions are influenced by topographical gradients.

  3. Avian vacuolar myelinopathy linked to exotic aquatic plants and a novel cyanobacterial species.

    PubMed

    Wilde, Susan B; Murphy, Thomas M; Hope, Charlotte P; Habrun, Sarah K; Kempton, Jason; Birrenkott, Anna; Wiley, Faith; Bowerman, William W; Lewitus, Alan J

    2005-06-01

    Invasions of exotic species have created environmental havoc through competition and displacement of native plants and animals. The introduction of hydrilla (Hydrilla verticillata) into the United States in the 1960s has been detrimental to navigation, power generation, water intake, and water quality (McCann et al., 1996). Our field surveys and feeding studies have now implicated exotic hydrilla and associated epiphytic cyanobacterial species as a link to avian vacuolar myelinopathy (AVM), an emerging avian disease affecting herbivorous waterbirds and their avian predators. AVM, first reported in 1994, has caused the death of at least 100 bald eagles (Haliaeetus leucocephalus) and thousands of American coots (Fulica americana) at 11 sites from Texas to North Carolina (Thomas et al., 1998; Rocke et al., 2002). Our working hypothesis is that the agent of this disease is an uncharacterized neurotoxin produced by a novel cyanobacterial epiphyte of the order Stigonematales. This undescribed species covers up to 95% of the surface area of leaves in reservoirs where bird deaths have occurred from the disease. In addition, this species is rare or not found on hydrilla collected at sites where AVM disease has not been diagnosed. Laboratory feeding trials and a sentinel bird study using naturally occurring blooms of cyanobacteria on hydrilla leaves and farm-raised mallard ducks (Anas platyrhynchos) induced the disease experimentally. Since 1994 AVM has been diagnosed in additional sites from Texas to North Carolina. Specific site characteristics that produce the disjunct distribution of AVM are unknown, but it is probable that the incidence of this disease will increase with the introduction of hydrilla and associated cyanobacterial species into additional ponds, lakes, and reservoirs. PMID:15892059

  4. Examining Ecological and Ecosystem Level Impacts of Aquatic Invasive Species in Lake Michigan Using An Ecosystem Productivity Model, LM-Eco

    EPA Science Inventory

    Ecological and ecosystem-level impacts of aquatic invasive species in Lake Michigan were examined using the Lake Michigan Ecosystem Model (LM-Eco). The LM-Eco model includes a detailed description of trophic levels and their interactions within the lower food web of Lake Michiga...

  5. Can we say: There is a <5% chance a new fish has invaded the St. Louis River? Evolving aquatic invasive species early detection

    EPA Science Inventory

    The Great Lakes Water Quality Agreement, Annex 6 calls for a U.S.-Canada, basin-wide aquatic invasive species early detection network by 2015. The objective of our research is to explore survey design strategies that can improve detection efficiency, and to develop performance me...

  6. DDT and Derivatives in Indicator Species of the Aquatic Food Web of Rangsit Agricultural Area, Central Thailand.

    PubMed

    Siriwong, W; Thirakhupt, K; Sitticharoenchai, D; Rohitrattana, J; Thongkongowm, P; Borjan, M; Robson, M

    2009-09-01

    The presence of DDT and derivatives in the food web of freshwater ecosystems of Rangsit agricultural area, Pathum Thani Province, Thailand were investigated from June 2004 to May 2007. By using gas chromatography (GC) with micro electron capture detector (mu ECD), DDT and derivatives in water, sediment, and fifteen indicator species i.e., 2 producers; Eichhornia crassipes and plankton (phyto- and zoo- plankton), an herbivore; Trichogaster microlepis (3) 3 omnivores; Trichogaster trichopterus, Oreochromis niloticus, and Puntius gonionotus, 6 carnivores; Channa striatus, Oxyeleotris marmoratus, Macrognathus siamensis, Parambassis siamensis, Anabas testudineus, and Pristolepis fasciatus, and 3 detritivores; Macrobrachium lanchesteri, Pomacea sp., and Filopaludina mertensi were measured. Results show low concentration levels (part per billion) of DDT & derivatives in each food web compartment i.e. water, sediment, aquatic plant, plankton, fish, and invertebrates. Magnification patterns, i.e. bioconcentration, bioaccumulation, and biomagnification, based on habitat and foraging behavior of selected freshwater species indicates that DDT & derivatives can accumulate and be magnified through the food chain from the lowest up to the highest trophic level. Therefore, the presence of residues and the evidence of magnification patterns can be observed as ecological indicators for evaluating ecological health risk.

  7. QSTR modeling for predicting aquatic toxicity of pharmacological active compounds in multiple test species for regulatory purpose.

    PubMed

    Singh, Kunwar P; Gupta, Shikha; Basant, Nikita

    2015-02-01

    High concentrations of pharmacological active compounds (PACs) detected in global drinking water resources and their toxicological implications in aquatic life has become a matter of concern compelling for the development of reliable QSTRs (qualitative/quantitative structure-toxicity relationships) for their risk assessment. Robust QSTRs, such as decision treeboost (DTB) and decision tree forest (DTF) models implementing stochastic gradient boosting and bagging algorithms were established by experimental toxicity data of structurally diverse PACs in daphnia using molecular descriptors for predicting toxicity of new untested compounds in multiple test species. Developed models were rigorously validated using OECD recommended internal and external validation procedures and predictive power tested with external data of different trophic level test species (algae and fish). Classification QSTRs (DTB, DTF) rendered accuracy of 98.73% and 97.47%, respectively in daphnia and 84.38%, 85.94% (algae), 78.46% and 79.23% (fish). On the other hand, the regression QSTRs (DTB, DTF) yielded squared correlation coefficient values of 0.831, 0.852 (daphnia), 0.534, 0.556 (algae) and 0.620, 0.637 (fish). QSTRs developed in this study passed the OECD validation criteria and performed better than reported earlier for predicting toxicity of PACs, and can be used for screening the new untested compounds for regulatory purpose.

  8. Backbone tree for Chaetothyriales with four new species of Minimelanolocus from aquatic habitats.

    PubMed

    Liu, Xiao-Ying; Udayanga, Dhanushka; Luo, Zong-Long; Chen, Li-Jiao; Zhou, De-Qun; Su, Hong Yan; Hyde, Kevin D

    2015-11-01

    We are studying the freshwater lignicolous fungi along a north-south latitudinal gradient in Asia. In this paper, fresh collections of Minimelanolocus from submerged wood in streams in Yunnan Province, China are characterised based on morphology and molecular phylogeny based on three rDNA regions: 18S (SSU), ITS1-5.8S-ITS2 (ITS) and 28S nuclear rDNA (LSU). The phylogenetic analysis of combined LSU and SSU sequence data and a separate analysis of ITS placed the isolates within the family Herpotrichiellaceae, order Chaetothyriales. An updated phylogenetic backbone tree for Chaetothyriales is provided with available ex-type and additional isolates. One of the isolates collected was identified as Minimelanolocus obscurus based on morphology and molecular data. Minimelanolocus aquaticus, M. asiaticus, M. curvatus and M. melanicus are described as new species considering the interspecific ITS variability and morphology. The phylogenetic placement of Minimelanolocus in Chaetothyriales is novel and provides new sequence data for the genus as a distinct lineage in Chaetothyriales. The conidial characters of all the known species in the genus are summarized. Descriptions and illustrations are provided for the five species of Minimelanolocus with notes on their taxonomy and phylogeny. PMID:26466879

  9. Aquatic Pest Control. Manual 99.

    ERIC Educational Resources Information Center

    Missouri Univ., Columbia. Agricultural Experiment Station.

    This training manual provides information needed to meet the minimum EPA standards for certification as a commercial applicator of pesticides in the aquatic pest control category. The text discusses various water use situations; aquatic weed identification; herbicide use and effects; and aquatic insects and their control. (CS)

  10. Aquatic tardigrades in the Great Smoky Mountains National Park, North Carolina and Tennessee, U.S.A., with the description of a new species of Thulinius (Tardigrada, Isohypsibiidae).

    PubMed

    Bertolani, Roberto; Bartels, Paul J; Guidetti, Roberto; Cesari, Michele; Nelson, Diane R

    2014-02-05

    As part of the All Taxa Biodiversity Inventory (http://www.dlia.org), an extensive survey of tardigrades has been conducted in the Great Smoky Mountains National Park (GSMNP) in Tennessee and North Carolina, U.S.A., by Bartels and Nelson. Freshwater tardigrades include three species in the aquatic genus Thulinius (Eutardigrada, Isohypsibiidae). A new species, Thulinius romanoi, described from stream sediment, is distinguished from all other congeners by having a sculptured cuticle. In addition, the presence of Thulinius augusti (Murray, 1907) was verified by combined morphological and molecular analysis, and nine specimens of a third species, Thulinius cf. saltursus, were also found. Thulinius augusti is a new record for the United States. Thulinius saltursus (Schuster, Toftner & Grigarick, 1978) was previously recorded in California and Ohio, but our specimens vary slightly in morphology. The list of tardigrades from streams in the GSMNP was updated to a total of 44 species, 22 of which were predominantly or exclusively aquatic.

  11. Aquatic tardigrades in the Great Smoky Mountains National Park, North Carolina and Tennessee, U.S.A., with the description of a new species of Thulinius (Tardigrada, Isohypsibiidae).

    PubMed

    Bertolani, Roberto; Bartels, Paul J; Guidetti, Roberto; Cesari, Michele; Nelson, Diane R

    2014-01-01

    As part of the All Taxa Biodiversity Inventory (http://www.dlia.org), an extensive survey of tardigrades has been conducted in the Great Smoky Mountains National Park (GSMNP) in Tennessee and North Carolina, U.S.A., by Bartels and Nelson. Freshwater tardigrades include three species in the aquatic genus Thulinius (Eutardigrada, Isohypsibiidae). A new species, Thulinius romanoi, described from stream sediment, is distinguished from all other congeners by having a sculptured cuticle. In addition, the presence of Thulinius augusti (Murray, 1907) was verified by combined morphological and molecular analysis, and nine specimens of a third species, Thulinius cf. saltursus, were also found. Thulinius augusti is a new record for the United States. Thulinius saltursus (Schuster, Toftner & Grigarick, 1978) was previously recorded in California and Ohio, but our specimens vary slightly in morphology. The list of tardigrades from streams in the GSMNP was updated to a total of 44 species, 22 of which were predominantly or exclusively aquatic. PMID:24870654

  12. Aquatic and terrestrial plant species with potential to remove heavy metals from storm-water.

    PubMed

    Fritioff, Asa; Greger, Maria

    2003-01-01

    Remediation of storm-water polluted with heavy metals should be possible in percolation systems, ponds, or wetlands. The aim of this work was to find plant species for such systems that are efficient in the uptake of Zn, Cu, Cd, and Pb. Plants were collected from percolation and wetland areas and analyzed for heavy metal concentrations. Results showed that submersed and free-floating plants had the capacity to take up high levels of Cu, Zn, and Pb into their shoots. With roots having a concentration factor above 1, the terrestrial plants show efficient stabilization of Cd and Zn and emergent plants show corresponding stabilisation of Zn. In addition, Potamogeton natans, Alisma plantago-aquatica, and Filipendula ulmaria were used in a controlled experiment. The shoots of P. natans and the roots of A. plantago-aquatica were found to accumulate even higher concentrations of Zn, Cu, and Pb than found in the field-harvested plants. Similar results were found for Cd in shoots and Pb in roots of F. ulmaria. Our conclusion is that submersed plant species seem to be the most efficient for removal of heavy metals from storm-water. PMID:14750429

  13. Bioaccumulation dynamics and exposure routes of Cd and Cu among species of aquatic mayflies

    USGS Publications Warehouse

    Cain, D.; Croteau, M.-N.; Luoma, S.

    2011-01-01

    Consumption of periphyton is a potentially important route of metal exposure to benthic invertebrate grazers. The present study examined the bioaccumulation kinetics of dissolved and dietary Cd and Cu in five species of mayflies (class Insecta). Artificial stream water and benthic diatoms were separately labeled with enriched stable metal isotopes to determine physiological rate constants used by a biokinetic bioaccumulation model. The model was employed to simulate the effects of metal partitioning between water and food, expressed as the bioconcentration factor (BCF), as well as ingestion rate (IR) and metal assimilation efficiency of food (AE), on the relative importance of water and food to metal bioaccumulation. For all test species, the contribution of dietary uptake of Cd and Cu increased with BCF. For a given BCF, the contribution of food to the body burden increased with kuf, the metal uptake rate constant from food that combined variation in IR and AE. To explore the relative importance of water and diet exposure routes under field conditions, we used estimated site-specific aqueous free-ion concentrations to model Cd and Cu accumulation from aqueous exposure, exclusively. The predicted concentrations accounted for less than 5% of the observed concentrations, implying that most bioaccumulated metal was acquired from food. At least for the taxa considered in this study, we conclude that consumption of metal-contaminated periphyton can result in elevated metal body burdens and potentially increase the risk of metal toxicity. ?? 2011 SETAC.

  14. RNA Editing in Chloroplasts of Spirodela polyrhiza, an Aquatic Monocotelydonous Species.

    PubMed

    Wang, Wenqin; Zhang, Wei; Wu, Yongrui; Maliga, Pal; Messing, Joachim

    2015-01-01

    RNA editing is the post-transcriptional conversion from C to U before translation, providing a unique feature in the regulation of gene expression. Here, we used a robust and efficient method based on RNA-seq from non-ribosomal total RNA to simultaneously measure chloroplast-gene expression and RNA editing efficiency in the Greater Duckweed, Spirodela polyrhiza, a species that provides a new reference for the phylogenetic studies of monocotyledonous plants. We identified 66 editing sites at the genome-wide level, with an average editing efficiency of 76%. We found that the expression levels of chloroplast genes were relatively constant, but 11 RNA editing sites show significant changes in editing efficiency, when fronds turn into turions. Thus, RNA editing efficiency contributes more to the yield of translatable transcripts than steady state mRNA levels. Comparison of RNA editing sites in coconut, Spirodela, maize, and rice suggests that RNA editing originated from a common ancestor. PMID:26517707

  15. RNA Editing in Chloroplasts of Spirodela polyrhiza, an Aquatic Monocotelydonous Species

    PubMed Central

    Wang, Wenqin; Zhang, Wei; Wu, Yongrui; Maliga, Pal; Messing, Joachim

    2015-01-01

    RNA editing is the post-transcriptional conversion from C to U before translation, providing a unique feature in the regulation of gene expression. Here, we used a robust and efficient method based on RNA-seq from non-ribosomal total RNA to simultaneously measure chloroplast-gene expression and RNA editing efficiency in the Greater Duckweed, Spirodela polyrhiza, a species that provides a new reference for the phylogenetic studies of monocotyledonous plants. We identified 66 editing sites at the genome-wide level, with an average editing efficiency of 76%. We found that the expression levels of chloroplast genes were relatively constant, but 11 RNA editing sites show significant changes in editing efficiency, when fronds turn into turions. Thus, RNA editing efficiency contributes more to the yield of translatable transcripts than steady state mRNA levels. Comparison of RNA editing sites in coconut, Spirodela, maize, and rice suggests that RNA editing originated from a common ancestor. PMID:26517707

  16. Influence of certain forces on evolution of synonymous codon usage bias in certain species of three basal orders of aquatic insects.

    PubMed

    Selva Kumar, C; Nair, Rahul R; Sivaramakrishnan, K G; Ganesh, D; Janarthanan, S; Arunachalam, M; Sivaruban, T

    2012-12-01

    Forces that influence the evolution of synonymous codon usage bias are analyzed in six species of three basal orders of aquatic insects. The rationale behind choosing six species of aquatic insects (three from Ephemeroptera, one from Plecoptera, and two from Odonata) for the present analysis is based on phylogenetic position at the basal clades of the Order Insecta facilitating the understanding of the evolution of codon bias and of factors shaping codon usage patterns in primitive clades of insect lineages and their subtle differences in some of their ecological and environmental requirements in terms of habitat-microhabitat requirements, altitudinal preferences, temperature tolerance ranges, and consequent responses to climate change impacts. The present analysis focuses on open reading frames of the 13 protein-coding genes in the mitochondrial genome of six carefully chosen insect species to get a comprehensive picture of the evolutionary intricacies of codon bias. In all the six species, A and T contents are observed to be significantly higher than G and C, and are used roughly equally. Since transcription hypothesis on codon usage demands A richness and T poorness, it is quite likely that mutation pressure may be the key factor associated with synonymous codon usage (SCU) variations in these species because the mutation hypothesis predicts AT richness and GC poorness in the mitochondrial DNA. Thus, AT-biased mutation pressure seems to be an important factor in framing the SCU variation in all the selected species of aquatic insects, which in turn explains the predominance of A and T ending codons in these species. This study does not find any association between microhabitats and codon usage variations in the mitochondria of selected aquatic insects. However, this study has identified major forces, such as compositional constraints and mutation pressure, which shape patterns of codon usage in mitochondrial genes in the primitive clades of insect lineages.

  17. Staphylococcus argensis sp. nov., a novel staphylococcal species isolated from an aquatic environment.

    PubMed

    Heß, Stefanie; Gallert, Claudia

    2015-08-01

    A staphylocoagulase-negative, novobiocin-susceptible strain (M4S-6T) of a species of the genus Staphylococcus was isolated from the river Argen in Southern Germany. It was assigned to the genus Staphylococcus due to the presence of the fatty acids, ai-C15 : 0, i-C15 : 0, i-C17 : 0, ai-C17 : 0, and of menaquinone (MK-7) in the cytoplasmic membrane, which are typical of coagulase-negative staphylococci. The polar lipid profile consisted of phosphatidylglycerol, diphosphatidylglycerol, an unknown phospholipid and an unknown glycolipid. Although the 16S gene sequence of strain M4S-6T revealed a 98% similarity with its closest relative, Staphylococcus pettenkoferi, it could be distinguished by several phenotypical and physiological markers. In contrast to S. pettenkoferi, M4S-6T was ornithine decarboxylase-positive, urease-negative and could use formiate and l-histidine as carbon-sources; nitrate was not reduced. Whereas S. pettenkoferi could grow with d(-)-mannitol, d-sorbitol, gluconic acid, l-proline, carboxymethylcellulose and lignosulfonate, M4S-6T was not able to grow with these substances. The results of 16S rRNA gene sequence analysis and of phenotypic testing indicated that M4S-6T was a representative of a novel species for which the name Staphylococcus argensis sp. nov., is proposed with the type strain M4S-6T (DSM 29875T = CIP 110904T).

  18. Impact of Environmentally Based Chemical Hardness on Uranium Speciation and Toxicity in Six Aquatic Species

    PubMed Central

    Goulet, Richard R; Thompson, Patsy A; Serben, Kerrie C; Eickhoff, Curtis V

    2015-01-01

    Treated effluent discharge from uranium (U) mines and mills elevates the concentrations of U, calcium (Ca), magnesium (Mg), and sulfate (SO42–) above natural levels in receiving waters. Many investigations on the effect of hardness on U toxicity have been experiments on the combined effects of changes in hardness, pH, and alkalinity, which do not represent water chemistry downstream of U mines and mills. Therefore, more toxicity studies with water chemistry encountered downstream of U mines and mills are necessary to support predictive assessments of impacts of U discharge to the environment. Acute and chronic U toxicity laboratory bioassays were realized with 6 freshwater species in waters of low alkalinity, circumneutral pH, and a range of chemical hardness as found in field samples collected downstream of U mines and mills. In laboratory-tested waters, speciation calculations suggested that free uranyl ion concentrations remained constant despite increasing chemical hardness. When hardness increased while pH remained circumneutral and alkalinity low, U toxicity decreased only to Hyalella azteca and Pseudokirchneriella subcapitata. Also, Ca and Mg did not compete with U for the same uptake sites. The present study confirms that the majority of studies concluding that hardness affected U toxicity were in fact studies in which alkalinity and pH were the stronger influence. The results thus confirm that studies predicting impacts of U downstream of mines and mills should not consider chemical hardness. PMID:25475484

  19. Arsenic species uptake and subcellular distribution in Vallisneria natans (Lour.) Hara as influenced by aquatic pH.

    PubMed

    Chen, Guoliang; Liu, Xingmei; Xu, Jianming; Brookes, Philip C; Wu, Jianjun

    2014-04-01

    Vallisneria natans (Lour.) Hara, a widely distributed submerged aquatic plant, is a promising species for arsenic (As) removal from contaminated water. We investigated the effects of pH on the accumulation, subcellular distribution and detoxification of As in V. natans. The results showed that the optimum pH for submerged V. natans growth is close to 7.0. The accumulation of As in the plant increased with the increase of pH (p < 0.05). This may have been due to arsenic/phosphate transporters with a higher affinity for the more highly electronegative AsO4 (3-) than for HAsO4 (2-) and H2AsO4 (-). After As(V) was accumulated by plants, more than 80 % was reduced to As(III), but As reduction decreased with increased pH. The majority of accumulated As and reduced As(III) (47 %-66 %) was found in the vacuoles. Higher As concentrations in vacuoles could be considered as an important mechanism for As detoxification in submerged plants. PMID:24420344

  20. Identification of aquatic Burkholderia (Pseudomonas) cepacia by hybridization with species-specific rRNA gene probes

    SciTech Connect

    Leff, L.G.; Kernan, R.M.; McArthur, J.V.

    1995-04-01

    Burkholderia (Pseudomonas) cepacia is a common environmental bacterium which can be pathogenic for plants and humans. In this study, four strategies were used to identify aquatic isolates: API test strips, hybridization with species-specific DNA probes for the 16S and 23S rRNA genes, fatty acid methyl ester (FAME) profiles, and growth on selective medium (TB-T agar [C. Hagedorn, W.D. Gould, T.R. Bardinelli, and D.R. Gustarson, Appl. Environ. Microbiol. 53:2265-2268, 1987]). Only 59% of the isolates identified as B. cepacia with the API test strips were confirmed as B. cepacia by using fatty acids profiles. The 23S rRNA probe generated a few false-positive results but dramatically underestimated the number of B. cepacia isolates (i.e., 40% of the colonies that did not hybridize to the probe were B. cepacia, as determined by FAME). The 16S rRNA probe generated more false-positive results than the 23S rRNA probe but was effective in identifying the majority of the B. cepacia isolates. The selective medium was only partially successful in recovering B. cepacia. Use of the B. cepacia-specific 16S rRNA probe was the most efficient and accurate way of identifying B. cepacia. 13 refs., 1 fig., 2 tabs.

  1. Cytochrome P-450 monooxygenase systems in aquatic species: Carcinogen metabolism and biomarkers for carcinogen and pollutant exposure

    SciTech Connect

    Stegeman, J.J. ); Lech, J.J. )

    1991-01-01

    High levels of polynuclear aromatic hydrocarbon (PAH) carcinogens commonly occur in aquatic systems where neoplasms arise in fish and other animals. Enzymes that transform PAHs can act in initiating these diseases and can indicate the contamination of fish by carcinogens and other pollutants. Cytochrome P-450 has similar roles in activating PAH carcinogens in fish and mammalian species. PAHs and many chlorinated hydrocarbons, e.g., polychlorinated biphenyls (PCBs) induce a form of cytochrome P-450 in fish that is the primary catalyst of PAH metabolism. The induction of this P-450 in fish can accelerate the disposition of hydrocarbons but can also enhance the formation of carcinogenic derivatives of PAHs. Invertebrates have lower rates of PAH metabolism than fish. The induction of P-450 forms can indicate the exposure of fish to PAHs, PCBs, and other toxic compounds. This is not restricted to carcinogens. Environmental induction has been detected in fish from contaminated areas by use of catalytic assay, antibodies to fish P-450, and cDNA probes that hybridize with P-450 messenger RNA. Application of these methods can provide sensitive biological monitoring tools that can detect environmental contamination of fish by some carcinogens and tumor promoters. The potential for using P-450 induction to detect direct-acting carcinogens and tumor promoters that are noninducers is limited, although such compounds can be expected to co-occur with pollutants that are inducers.

  2. Austromesocypris bluffensis sp. n. (Crustacea, Ostracoda, Cypridoidea, Scottiinae) from subterranean aquatic habitats in Tasmania, with a key to world species of the subfamily

    PubMed Central

    Karanovic, Ivana; Eberhard, Stefan; Perina, Giulia

    2012-01-01

    Abstract Austromesocypris bluffensis sp. n. is described and we report another species, Austromesocypris sp., both collected from subterranean aquatic habitats in Tasmania. This discovery adds a major taxonomic group to the already diverse invertebrate cave fauna of Tasmania, and is of interest because, globally, obligate subterranean aquatic species (stygobites) are poorly represented within the family Cyprididae. The genus Austromesocypris Martens, De Deckker & Rossetti, 2004 is otherwise known to comprise entirely “terrestrial or semi-terrestrial” species. The second species is not described because only juvenile specimens were collected. Both species stand apart from their congeners by the carapace shape, which is rectangular in Austromesocypris bluffensis and triangular and asymmetrical in the unnamed species. Another unique feature of the new species is the almost symmetrical uropodal rami. We also identify some broader systematic issues within the Scottiinae including the position of two New Zealand species, Scottia audax (Chapman, 1961) and Scottia insularis Chapman, 1963 in the genus, and point out their closer relationship to the Gondwana genera of Scottiinae, Austromesocypris and Mesocypris Daday, 1910, than to the Palearctic genus Scottia Brady & Norman, 1889, based on the morphology of the maxillula and mandibula. The identity of the Australian records of Scottia audax (Chapman, 1961), Austromesocypris australiensis (De Deckker, 1983) and the Boreal records of Scottia pseudobrowniana Kempf, 1971 are all considered doubtful. A key to the world species of Scottiinae is provided. PMID:22936868

  3. The AquaDEB project (phase I): Analysing the physiological flexibility of aquatic species and connecting physiological diversity to ecological and evolutionary processes by using Dynamic Energy Budgets

    NASA Astrophysics Data System (ADS)

    Alunno-Bruscia, Marianne; van der Veer, Henk W.; Kooijman, Sebastiaan A. L. M.

    2009-08-01

    The European Research Project AquaDEB (2007-2011, http://www.ifremer.fr/aquadeb/) is joining skills and expertise of some French and Dutch research institutes and universities to analyse the physiological flexibility of aquatic organisms and to link it to ecological and evolutionary processes within a common theoretical framework for quantitative bioenergetics [Kooijman, S.A.L.M., 2000. Dynamic energy and mass budgets in biological systems. Cambridge University Press, Cambridge]. The main scientific objectives in AquaDEB are i) to study and compare the sensitivity of aquatic species (mainly molluscs and fish) to environmental variability of natural or human origin, and ii) to evaluate the related consequences at different biological levels (individual, population, ecosystem) and temporal scales (life cycle, population dynamics, evolution). At mid-term life, the AquaDEB collaboration has already yielded interesting results by quantifying bio-energetic processes of various aquatic species (e.g. molluscs, fish, crustaceans, algae) with a single mathematical framework. It has also allowed to federate scientists with different backgrounds, e.g. mathematics, microbiology, ecology, chemistry, and working in different fields, e.g. aquaculture, fisheries, ecology, agronomy, ecotoxicology, climate change. For the two coming years, the focus of the AquaDEB collaboration will be in priority: (i) to compare energetic and physiological strategies among species through the DEB parameter values and to identify the factors responsible for any differences in bioenergetics and physiology; and to compare dynamic (DEB) versus static (SEB) energy models to study the physiological performance of aquatic species; (ii) to consider different scenarios of environmental disruption (excess of nutrients, diffuse or massive pollution, exploitation by man, climate change) to forecast effects on growth, reproduction and survival of key species; (iii) to scale up the models for a few species from

  4. Impact of environmentally based chemical hardness on uranium speciation and toxicity in six aquatic species.

    PubMed

    Goulet, Richard R; Thompson, Patsy A; Serben, Kerrie C; Eickhoff, Curtis V

    2015-03-01

    Treated effluent discharge from uranium (U) mines and mills elevates the concentrations of U, calcium (Ca), magnesium (Mg), and sulfate (SO4 (2-) ) above natural levels in receiving waters. Many investigations on the effect of hardness on U toxicity have been experiments on the combined effects of changes in hardness, pH, and alkalinity, which do not represent water chemistry downstream of U mines and mills. Therefore, more toxicity studies with water chemistry encountered downstream of U mines and mills are necessary to support predictive assessments of impacts of U discharge to the environment. Acute and chronic U toxicity laboratory bioassays were realized with 6 freshwater species in waters of low alkalinity, circumneutral pH, and a range of chemical hardness as found in field samples collected downstream of U mines and mills. In laboratory-tested waters, speciation calculations suggested that free uranyl ion concentrations remained constant despite increasing chemical hardness. When hardness increased while pH remained circumneutral and alkalinity low, U toxicity decreased only to Hyalella azteca and Pseudokirchneriella subcapitata. Also, Ca and Mg did not compete with U for the same uptake sites. The present study confirms that the majority of studies concluding that hardness affected U toxicity were in fact studies in which alkalinity and pH were the stronger influence. The results thus confirm that studies predicting impacts of U downstream of mines and mills should not consider chemical hardness. Environ Toxicol Chem 2015;34:562-574. © 2014 The Authors. Published by Wiley Periodicals, Inc. on behalf of SETAC.

  5. Impact of environmentally based chemical hardness on uranium speciation and toxicity in six aquatic species.

    PubMed

    Goulet, Richard R; Thompson, Patsy A; Serben, Kerrie C; Eickhoff, Curtis V

    2015-03-01

    Treated effluent discharge from uranium (U) mines and mills elevates the concentrations of U, calcium (Ca), magnesium (Mg), and sulfate (SO4 (2-) ) above natural levels in receiving waters. Many investigations on the effect of hardness on U toxicity have been experiments on the combined effects of changes in hardness, pH, and alkalinity, which do not represent water chemistry downstream of U mines and mills. Therefore, more toxicity studies with water chemistry encountered downstream of U mines and mills are necessary to support predictive assessments of impacts of U discharge to the environment. Acute and chronic U toxicity laboratory bioassays were realized with 6 freshwater species in waters of low alkalinity, circumneutral pH, and a range of chemical hardness as found in field samples collected downstream of U mines and mills. In laboratory-tested waters, speciation calculations suggested that free uranyl ion concentrations remained constant despite increasing chemical hardness. When hardness increased while pH remained circumneutral and alkalinity low, U toxicity decreased only to Hyalella azteca and Pseudokirchneriella subcapitata. Also, Ca and Mg did not compete with U for the same uptake sites. The present study confirms that the majority of studies concluding that hardness affected U toxicity were in fact studies in which alkalinity and pH were the stronger influence. The results thus confirm that studies predicting impacts of U downstream of mines and mills should not consider chemical hardness. Environ Toxicol Chem 2015;34:562-574. © 2014 The Authors. Published by Wiley Periodicals, Inc. on behalf of SETAC. PMID:25475484

  6. Chemical species of metallic elements in the aquatic environment of an ex-mining catchment.

    PubMed

    Ashraf, Muhammad Aqeel; Ahmad, Mushtaq; Akib, Shatirah; Balkhair, Khaled S; Abu Bakar, Nor Kartini

    2014-08-01

    This study was conducted to investigate the chemical speciation of dissolved and particulate elements (lead, zinc, copper, chromium, arsenic, and tin) in the mining wastewater of a former tin-mining catchment. The speciation patterns of dissolved elements were estimated by an adsorptive stripping voltammeter (ASV), while particulate elements were analyzed by using a newly developed sequential-extraction leaching procedure. The procedure has been operationally defined among five host fractions, namely exchangeable, carbonate, reducible, organic bound, and residual fractions. A total of six elements (lead, zinc, copper, chromium, arsenic, and tin) were analyzed in thirty samples at ten locations (P1-P10), with three samples taken from each of the ten locations, to get the average value from the former tin-mining catchment. The results showed that the heavy metal pollutions in locations P4 and P8 were more severe than in other sampling sites, especially tin and lead pollution. In the water samples from locations P4 and P8, both the total contents and the most dangerous non-residual fractions of tin and lead were extremely high. More than 90% of the total concentrations of arsenic and chromium existed in the residual fraction. Concentrations of copper and zinc mainly occurred in the residual fraction (more than 60%), while lead and tin presented mostly in the non-residual fractions in surface water. For all of the six dissolved elements, the less-labile species formed the predominant fraction in their speciation patterns. The speciation patterns of particulate elements showed that most of the concentrations of zinc, copper, chromium, and arsenic were found in the reducible fraction; whereas lead and tin were mainly associated with the organic fraction.

  7. Effects of the environmental estrogenic contaminants bisphenol A and 17α-ethinyl estradiol on sexual development and adult behaviors in aquatic wildlife species

    USGS Publications Warehouse

    Bhandari, Ramji K.; Deem, Sharon L.; Holliday, Dawn K.; Jandegian, Caitlin M.; Kassotis, Christopher D.; Nagel, Susan C.; Tillitt, Donald E.; vom Saal, Frederick S.; Rosenfeld, Cheryl S.

    2015-01-01

    Endocrine disrupting chemicals (EDCs), including the mass-produced component of plastics, bisphenol A (BPA) are widely prevalent in aquatic and terrestrial habitats. Many aquatic species, such as fish, amphibians, aquatic reptiles and mammals, are exposed daily to high concentrations of BPA and ethinyl estradiol (EE2), estrogen in birth control pills. In this review, we will predominantly focus on BPA and EE2, well-described estrogenic EDCs. First, the evidence that BPA and EE2 are detectable in almost all bodies of water will be discussed. We will consider how BPA affects sexual and neural development in these species, as these effects have been the best characterized across taxa. For instance, such chemicals have been in many cases reported to cause sex-reversal of males to females. Even if these chemicals do not overtly alter the gonadal sex, there are indications that several EDCs might demasculinize male-specific behaviors that are essential for attracting a mate. In so doing, these chemicals may reduce the likelihood that these males reproduce. If exposed males do reproduce, the concern is that they will then be passing on compromised genetic fitness to their offspring and transmitting potential transgenerational effects through their sperm epigenome. We will thus consider how diverse epigenetic changes might be a unifying mechanism of how BPA and EE2 disrupt several processes across species. Such changes might also serve as universal species diagnostic biomarkers of BPA and other EDCs exposure. Lastly, the evidence that estrogenic EDCs-induced effects in aquatic species might translate to humans will be considered.

  8. Effects of the environmental estrogenic contaminants bisphenol A and 17α-ethinyl estradiol on sexual development and adult behaviors in aquatic wildlife species.

    PubMed

    Bhandari, Ramji K; Deem, Sharon L; Holliday, Dawn K; Jandegian, Caitlin M; Kassotis, Christopher D; Nagel, Susan C; Tillitt, Donald E; Vom Saal, Frederick S; Rosenfeld, Cheryl S

    2015-04-01

    Endocrine disrupting chemicals (EDCs), including the mass-produced component of plastics, bisphenol A (BPA) are widely prevalent in aquatic and terrestrial habitats. Many aquatic species, such as fish, amphibians, aquatic reptiles and mammals, are exposed daily to high concentrations of BPA and ethinyl estradiol (EE2), estrogen in birth control pills. In this review, we will predominantly focus on BPA and EE2, well-described estrogenic EDCs. First, the evidence that BPA and EE2 are detectable in almost all bodies of water will be discussed. We will consider how BPA affects sexual and neural development in these species, as these effects have been the best characterized across taxa. For instance, such chemicals have been in many cases reported to cause sex-reversal of males to females. Even if these chemicals do not overtly alter the gonadal sex, there are indications that several EDCs might demasculinize male-specific behaviors that are essential for attracting a mate. In so doing, these chemicals may reduce the likelihood that these males reproduce. If exposed males do reproduce, the concern is that they will then be passing on compromised genetic fitness to their offspring and transmitting potential transgenerational effects through their sperm epigenome. We will thus consider how diverse epigenetic changes might be a unifying mechanism of how BPA and EE2 disrupt several processes across species. Such changes might also serve as universal species diagnostic biomarkers of BPA and other EDCs exposure. Lastly, the evidence that estrogenic EDCs-induced effects in aquatic species might translate to humans will be considered. PMID:25277515

  9. Survey of aquatic macroinvertebrates and amphibians at Wupatki National Monument, Arizona, USA: An evaluation of selected factors affecting species richness in ephemeral pools

    USGS Publications Warehouse

    Graham, T.B.

    2002-01-01

    Ephemeral aquatic habitats in Wupatki National Monument vary from naturally formed pools in arroyos over 5000 years old, to constructed catchment basins with ages estimated at 60-1000+ years old, and borrow pits and stock ponds 30-60 years old. The different ages of these pools provide different histories of colonization by amphibians and aquatic invertebrates, especially temporary pool specialists such as spadefoot toads and branchiopod crustaceans. Ten pools of five different origins and ages were surveyed in August and/or September 1997 for aquatic organisms; a total of 13 surveys were conducted. Twenty-two taxa were found, with the number of species in a pool during any survey ranging from one to 10. Species composition of the communities changed from one sampling date to the next within individual pools. Community structure is an amalgam of species with different dispersal mechanisms that are influenced by different pool characteristics. Age appears to have little effect overall, but may have influenced branchiopod presence/absence. Distance to permanent water, frequency of disturbance, and current pool size were correlated with presence/absence of some species.

  10. Cytochrome P-450 monooxygenase systems in aquatic species: carcinogen metabolism and biomarkers for carcinogen and pollutant exposure.

    PubMed Central

    Stegeman, J J; Lech, J J

    1991-01-01

    High levels of polynuclear aromatic hydrocarbon (PAH) carcinogens commonly occur in aquatic systems where neoplasms arise in fish and other animals. Enzymes that transform PAHs can act in initiating these diseases and can indicate the contamination of fish by carcinogens and other pollutants. Cytochrome P-450 has similar roles in activating PAH carcinogens in fish and mammalian species. PAHs and many chlorinated hydrocarbons, e.g., polychlorinated biphenyls (PCBs) induce a form of cytochrome P-450 in fish that is the primary catalyst of PAH metabolism. The induction of this P-450 in fish can accelerate the disposition of hydrocarbons, but can also enhance the formation of carcinogenic derivatives of PAHs. Invertebrates have lower rates of PAH metabolism than fish. These rates are not obviously inducible by exposure to PAHs or PCBs. The lower rates of foreign compound metabolism contribute to higher pollutant residue levels in bivalve mollusks (clams, mussels, etc.) than in fish and may limit the involvement of some procarcinogens (requiring activation) in disease processes in invertebrates. The induction of P-450 forms can indicate the exposure of fish to PAHs, PCBs, and other toxic compounds. This is not restricted to carcinogens. Environmental induction has been detected in fish from contaminated areas by use of catalytic assay, antibodies to fish P-450, and cDNA probes that hybridize with P-450 messenger RNA. Application of these methods can provide sensitive biological monitoring tools that can detect environmental contamination of fish by some carcinogens and tumor promoters.(ABSTRACT TRUNCATED AT 250 WORDS) PMID:2050047

  11. Hypoxanthine-guanine phosphoribosyltransferase and inosine 5′-monophosphate dehydrogenase activities in three mammalian species: aquatic (Mirounga angustirostris), semi-aquatic (Lontra longicaudis annectens) and terrestrial (Sus scrofa)

    PubMed Central

    Barjau Pérez-Milicua, Myrna; Zenteno-Savín, Tania; Crocker, Daniel E.; Gallo-Reynoso, Juan P.

    2015-01-01

    Aquatic and semiaquatic mammals have the capacity of breath hold (apnea) diving. Northern elephant seals (Mirounga angustirostris) have the ability to perform deep and long duration dives; during a routine dive, adults can hold their breath for 25 min. Neotropical river otters (Lontra longicaudis annectens) can hold their breath for about 30 s. Such periods of apnea may result in reduced oxygen concentration (hypoxia) and reduced blood supply (ischemia) to tissues. Production of adenosine 5′-triphosphate (ATP) requires oxygen, and most mammalian species, like the domestic pig (Sus scrofa), are not adapted to tolerate hypoxia and ischemia, conditions that result in ATP degradation. The objective of this study was to explore the differences in purine synthesis and recycling in erythrocytes and plasma of three mammalian species adapted to different environments: aquatic (northern elephant seal) (n = 11), semiaquatic (neotropical river otter) (n = 4), and terrestrial (domestic pig) (n = 11). Enzymatic activity of hypoxanthine-guanine phosphoribosyltransferase (HGPRT) was determined by spectrophotometry, and activity of inosine 5′-monophosphate dehydrogenase (IMPDH) and the concentration of hypoxanthine (HX), inosine 5′-monophosphate (IMP), adenosine 5′-monophosphate (AMP), adenosine 5′-diphosphate (ADP), ATP, guanosine 5′-diphosphate (GDP), guanosine 5′-triphosphate (GTP), and xanthosine 5′-monophosphate (XMP) were determined by high-performance liquid chromatography (HPLC). The activities of HGPRT and IMPDH and the concentration of HX, IMP, AMP, ADP, ATP, GTP, and XMP in erythrocytes of domestic pigs were higher than in erythrocytes of northern elephant seals and river otters. These results suggest that under basal conditions (no diving, sleep apnea or exercise), aquatic, and semiaquatic mammals have less purine mobilization than their terrestrial counterparts. PMID:26283971

  12. Assessing contaminant sensitivity of endangered and threatened aquatic species: Part II. chronic toxicity of copper and pentachlorophenol to two endangered species and two surrogate species

    USGS Publications Warehouse

    Besser, J.M.; Wang, N.; Dwyer, F.J.; Mayer, F.L.; Ingersoll, C.G.

    2005-01-01

    Early life-stage toxicity tests with copper and pentachlorophenol (PCP) were conducted with two species listed under the United States Endangered Species Act (the endangered fountain darter, Etheostoma fonticola, and the threatened spotfin chub, Cyprinella monacha) and two commonly tested species (fathead minnow, Pimephales promelas, and rainbow trout, Oncorhynchus mykiss). Results were compared using lowest-observed effect concentrations (LOECs) based on statistical hypothesis tests and by point estimates derived by linear interpolation and logistic regression. Sublethal end points, growth (mean individual dry weight) and biomass (total dry weight per replicate) were usually more sensitive than survival. The biomass end point was equally sensitive as growth and had less among-test variation. Effect concentrations based on linear interpolation were less variable than LOECs, which corresponded to effects ranging from 9% to 76% relative to controls and were consistent with thresholds based on logistic regression. Fountain darter was the most sensitive species for both chemicals tested, with effect concentrations for biomass at ??? 11 ??g/L (LOEC and 25% inhibition concentration [IC25]) for copper and at 21 ??g/L (IC25) for PCP, but spotfin chub was no more sensitive than the commonly tested species. Effect concentrations for fountain darter were lower than current chronic water quality criteria for both copper and PCP. Protectiveness of chronic water-quality criteria for threatened and endangered species could be improved by the use of safety factors or by conducting additional chronic toxicity tests with species and chemicals of concern. ?? 2005 Springer Science+Business Media, Inc.

  13. 77 FR 52314 - Atlantic Highly Migratory Species; Meeting of the Atlantic Highly Migratory Species Advisory Panel

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-08-29

    ... items contained in the Advanced Notice of Proposed Rulemaking that published on June 1, 2009 (74 FR.... FOR FURTHER INFORMATION CONTACT: Jenni Wallace or Margo Schulze-Haugen at (301) 427-8503... Wallace at (301) 427-8503 at least 7 days prior to the meeting. Dated: August 24, 2012. Lindsay...

  14. SAP Minutes No.2015-03 for FIFRA meeting held 9/15-17/2015. A set of scientific issues being considered by the Environmental Protection Agency regarding development of a spatial aquatic model(SAM)for pesticide risk assessment

    Technology Transfer Automated Retrieval System (TEKTRAN)

    On September 15-17th, 2014, the US Environmental Protection Agency convened a public meeting of the FIFRA Scientific Advisory Panel (SAP) to address scientific issues associated with the agency’s “Development of a Spatial Aquatic Model (SAM) for Pesticide Risk Assessment”. The goal of SAM is to impr...

  15. Can Recent Global Changes Explain the Dramatic Range Contraction of an Endangered Semi-Aquatic Mammal Species in the French Pyrenees?

    PubMed

    Charbonnel, Anaïs; Laffaille, Pascal; Biffi, Marjorie; Blanc, Frédéric; Maire, Anthony; Némoz, Mélanie; Sanchez-Perez, José Miguel; Sauvage, Sabine; Buisson, Laëtitia

    2016-01-01

    Species distribution models (SDMs) are the main tool to predict global change impacts on species ranges. Climate change alone is frequently considered, but in freshwater ecosystems, hydrology is a key driver of the ecology of aquatic species. At large scale, hydrology is however rarely accounted for, owing to the lack of detailed stream flow data. In this study, we developed an integrated modelling approach to simulate stream flow using the hydrological Soil and Water Assessment Tool (SWAT). Simulated stream flow was subsequently included as an input variable in SDMs along with topographic, hydrographic, climatic and land-cover descriptors. SDMs were applied to two temporally-distinct surveys of the distribution of the endangered Pyrenean desman (Galemys pyrenaicus) in the French Pyrenees: a historical one conducted from 1985 to 1992 and a current one carried out between 2011 and 2013. The model calibrated on historical data was also forecasted onto the current period to assess its ability to describe the distributional change of the Pyrenean desman that has been modelled in the recent years. First, we found that hydrological and climatic variables were the ones influencing the most the distribution of this species for both periods, emphasizing the importance of taking into account hydrology when SDMs are applied to aquatic species. Secondly, our results highlighted a strong range contraction of the Pyrenean desman in the French Pyrenees over the last 25 years. Given that this range contraction was under-estimated when the historical model was forecasted onto current conditions, this finding suggests that other drivers may be interacting with climate, hydrology and land-use changes. Our results imply major concerns for the conservation of this endemic semi-aquatic mammal since changes in climate and hydrology are expected to become more intense in the future.

  16. Can Recent Global Changes Explain the Dramatic Range Contraction of an Endangered Semi-Aquatic Mammal Species in the French Pyrenees?

    PubMed Central

    Charbonnel, Anaïs; Laffaille, Pascal; Biffi, Marjorie; Blanc, Frédéric; Maire, Anthony; Némoz, Mélanie; Sanchez-Perez, José Miguel; Sauvage, Sabine

    2016-01-01

    Species distribution models (SDMs) are the main tool to predict global change impacts on species ranges. Climate change alone is frequently considered, but in freshwater ecosystems, hydrology is a key driver of the ecology of aquatic species. At large scale, hydrology is however rarely accounted for, owing to the lack of detailed stream flow data. In this study, we developed an integrated modelling approach to simulate stream flow using the hydrological Soil and Water Assessment Tool (SWAT). Simulated stream flow was subsequently included as an input variable in SDMs along with topographic, hydrographic, climatic and land-cover descriptors. SDMs were applied to two temporally-distinct surveys of the distribution of the endangered Pyrenean desman (Galemys pyrenaicus) in the French Pyrenees: a historical one conducted from 1985 to 1992 and a current one carried out between 2011 and 2013. The model calibrated on historical data was also forecasted onto the current period to assess its ability to describe the distributional change of the Pyrenean desman that has been modelled in the recent years. First, we found that hydrological and climatic variables were the ones influencing the most the distribution of this species for both periods, emphasizing the importance of taking into account hydrology when SDMs are applied to aquatic species. Secondly, our results highlighted a strong range contraction of the Pyrenean desman in the French Pyrenees over the last 25 years. Given that this range contraction was under-estimated when the historical model was forecasted onto current conditions, this finding suggests that other drivers may be interacting with climate, hydrology and land-use changes. Our results imply major concerns for the conservation of this endemic semi-aquatic mammal since changes in climate and hydrology are expected to become more intense in the future. PMID:27467269

  17. The semi-aquatic freshwater earthworms of the genus Glyphidrilus Horst, 1889 from Thailand (Oligochaeta, Almidae) with re-descriptions of several species.

    PubMed

    Chanabun, Ratmanee; Sutcharit, Chirasak; Tongkerd, Piyoros; Panha, Somsak

    2013-01-01

    The semi-aquatic freshwater earthworm genus Glyphidrilus Horst, 1889 from Thailand was investigated based on extensive recent collecting. The species in this genus were characterized by their external and internal morphological characters of the location of wings, genital openings, genital organ structures and their locations, as well as the dimensions of body length and number of segments. Several type specimens were compared with both previous and newly collected materials. Ten new species are described from several river systems in Thailand; as Glyphidrilus borealis sp. n., Glyphidrilus chaophraya sp. n., Glyphidrilus chiensis sp. n., Glyphidrilus huailuangensis sp. n., Glyphidrilus kratuensis sp. n., Glyphidrilus quadratus sp. n., Glyphidrilus trangensis sp. n., Glyphidrilus wararamensis sp. n., Glyphidrilus vangthongensis sp. n. and Glyphidrilus vesper sp. n. Each species is endemic to a single river system. All 26 previously described species are re-described, and eight lectotypes have been designated. An identification key and a morphological comparison summary are provided.

  18. Evaluation of poly-aromatic hydrocarbons (PAHs) in the aquatic species of Suez Gulf water along El-Sokhna area to the Suez refineries.

    PubMed

    Ali, Nabila A; Ahmed, Omayma E; Doheim, Mamdouh M

    2014-02-01

    The Egyptian Red Sea environment especially along El-Sokhna area to the Suez refineries (Suez) is severely contaminated with organic compounds, as well as overfishing. This may be well contributory to recent serious declines in fish stocks. Fish embryos are also particularly vulnerable to oil exposure, even at extremely low concentrations of less than one part per billion. Consequently, even traces of oil pollution at levels often considered safe for wildlife can cause severe damage to fish. Sixteen polycyclic aromatic hydrocarbons (PAHs) were investigated in ten fish species of aquatic species by high performance liquid chromatography (HPLC). The compositions of PAHs determined in all samples were measured in order to use them as chemical markers for identifying different sources of PAH pollutants in the studied region. The total content of these16 PAHs ranged from 399.616 up to 67,631.779 ng/g wet weight. The data show that these values are considered to be alarmingly high enough to cause lethal toxicity effect by accumulation. All studied aquatic species samples are characterized by relatively high concentrations of the six-membered ring PAHs. The origin of PAHs in the collected samples is either petrogenic, biogenic, or mixed petrogenic and biogenic. PMID:24092254

  19. Evaluation of poly-aromatic hydrocarbons (PAHs) in the aquatic species of Suez Gulf water along El-Sokhna area to the Suez refineries.

    PubMed

    Ali, Nabila A; Ahmed, Omayma E; Doheim, Mamdouh M

    2014-02-01

    The Egyptian Red Sea environment especially along El-Sokhna area to the Suez refineries (Suez) is severely contaminated with organic compounds, as well as overfishing. This may be well contributory to recent serious declines in fish stocks. Fish embryos are also particularly vulnerable to oil exposure, even at extremely low concentrations of less than one part per billion. Consequently, even traces of oil pollution at levels often considered safe for wildlife can cause severe damage to fish. Sixteen polycyclic aromatic hydrocarbons (PAHs) were investigated in ten fish species of aquatic species by high performance liquid chromatography (HPLC). The compositions of PAHs determined in all samples were measured in order to use them as chemical markers for identifying different sources of PAH pollutants in the studied region. The total content of these16 PAHs ranged from 399.616 up to 67,631.779 ng/g wet weight. The data show that these values are considered to be alarmingly high enough to cause lethal toxicity effect by accumulation. All studied aquatic species samples are characterized by relatively high concentrations of the six-membered ring PAHs. The origin of PAHs in the collected samples is either petrogenic, biogenic, or mixed petrogenic and biogenic.

  20. CDFISH: an individual-based, spatially-explicit, landscape genetics simulator for aquatic species in complex riverscapes

    USGS Publications Warehouse

    Erin L. Landguth,; Muhlfeld, Clint C.; Luikart, Gordon

    2012-01-01

    We introduce Cost Distance FISHeries (CDFISH), a simulator of population genetics and connectivity in complex riverscapes for a wide range of environmental scenarios of aquatic organisms. The spatially-explicit program implements individual-based genetic modeling with Mendelian inheritance and k-allele mutation on a riverscape with resistance to movement. The program simulates individuals in subpopulations through time employing user-defined functions of individual migration, reproduction, mortality, and dispersal through straying on a continuous resistance surface.

  1. Conference on Professional Standards for Aquatic Education.

    ERIC Educational Resources Information Center

    American Association for Health, Physical Education, and Recreation, Washington, DC.

    This report on the 1970 meeting of the Aquatics Council of the American Association for Health, Physical Education, and Recreation is divided into three sections reflecting the three phases of the Council's interest. Section One is devoted to basic aquatic education for the physical educator. Section Two concerns basic aquatic education for the…

  2. Mapping freshwater deltaic wetlands and aquatic habitats at multiple scales with high-resolution multispectral WorldView-2 imagery and Indicator Species Analysis

    NASA Astrophysics Data System (ADS)

    Lane, C.; Liu, H.; Anenkhonov, O.; Autrey, B.; Chepinoga, V.

    2012-12-01

    Remote sensing technology has long been used in wetland inventory and monitoring though derived wetland maps were limited in applicability and often unsatisfactory largely due to the relatively coarse spatial resolution of conventional satellite imagery. The advent of high-resolution multispectral satellite systems presents new and exciting capabilities in mapping wetland systems with unprecedented accuracy and spatial detail. This research explores and evaluates the use of high-resolution WorldView-2 (WV2) multispectral imagery in identifying and classifying freshwater deltaic wetland vegetation and aquatic habitats in the Selenga River Delta, a Ramsar Wetland of International Importance that drains into Lake Baikal, Russia - a United Nations World Heritage site. A hybrid approach was designed and applied for WV2 image classification consisting of initial unsupervised classification, training data acquisition and analysis, indicator species analysis, and final supervised classification. A hierarchical scheme was defined and adopted for classifying aquatic habitats and wetland vegetation at genus and community levels at a fine scale, while at a coarser scale representing wetland systems as broad substrate and vegetation classes for regional comparisons under various existing wetland classification systems. Rigorous radiometric correction of WV2 images and orthorectification based on GPS-derived ground control points and an ASTER global digital elevation model resulted in 2- to 3-m positional accuracy. We achieved overall classification accuracy of 86.5% for 22 classes of wetland and aquatic habitats at the finest scale and >91% accuracy for broad vegetation and aquatic classes at more generalized scales. At the finest scale, the addition of four new WV2 spectral bands contributed to a classification accuracy increase of 3.5%. The coastal band of WV2 was found to increase the separation between different open water and aquatic habitats, while yellow, red-edge, and

  3. A New Species of Devosia That Forms a Unique Nitrogen-Fixing Root-Nodule Symbiosis with the Aquatic Legume Neptunia natans (L.f.) Druce

    PubMed Central

    Rivas, Raul; Velázquez, Encarna; Willems, Anne; Vizcaíno, Nieves; Subba-Rao, Nanjappa S.; Mateos, Pedro F.; Gillis, Monique; Dazzo, Frank B.; Martínez-Molina, Eustoquio

    2002-01-01

    Rhizobia are the common bacterial symbionts that form nitrogen-fixing root nodules in legumes. However, recently other bacteria have been shown to nodulate and fix nitrogen symbiotically with these plants. Neptunia natans is an aquatic legume indigenous to tropical and subtropical regions and in African soils is nodulated by Allorhizobium undicola. This legume develops an unusual root-nodule symbiosis on floating stems in aquatic environments through a unique infection process. Here, we analyzed the low-molecular-weight RNA and 16S ribosomal DNA (rDNA) sequence of the same fast-growing isolates from India that were previously used to define the developmental morphology of the unique infection process in this symbiosis with N. natans and found that they are phylogenetically located in the genus Devosia, not Allorhizobium or Rhizobium. The 16S rDNA sequences of these two Neptunia-nodulating Devosia strains differ from the only species currently described in that genus, Devosia riboflavina. From the same isolated colonies, we also located their nodD and nifH genes involved in nodulation and nitrogen fixation on a plasmid of approximately 170 kb. Sequence analysis showed that their nodD and nifH genes are most closely related to nodD and nifH of Rhizobium tropici, suggesting that this newly described Neptunia-nodulating Devosia species may have acquired these symbiotic genes by horizontal transfer. PMID:12406707

  4. Preliminary comparison of the uptake of chromium-51 and zinc-65 by three species of aquatic plants from Louisiana

    SciTech Connect

    Sklar, F.H.

    1980-12-01

    Accumulation of radionuclides was much greater for duckweed (Spirodela punctata) than for larger aquatic plants of slower growth (Bacopa caroliniana and Elodea canadensis). Higher specific activity (dpm/gm) was recorded in leaves than in stems. Chromium-51 accumulation factors ranged from a low of 66 for stems of E. canadensis to a high of 436 for S. punctata fronds. Zinc-65 accumulation factors were much higher: 142 for stems of B. caroliniana and 18,118 for fronds of S. punctata. Significant reductions in zinc-65 activity in the water surrounding growing S. punctata was detected within 10 minutes.

  5. Aquatic Environments

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Aquatic microbiology can be defined as the study of microorganisms and microbial communities in water environments. Aquatic environments occupy more than 70% of the earth’s surface including oceans, estuaries, rivers, lakes, wetlands, streams, springs, and aquifers. Water is essential for life and m...

  6. AQUATIC ECOSYSTEMS,

    EPA Science Inventory

    Aquatic ecosystems are a vital part of the urban water cycle (and of urban areas more broadly), and, if healthy, provide a range of goods and services valued by humans (Meyer 1997). For example, aquatic ecosystems (e.g., rivers, lakes, wetlands) provide potable water, food resou...

  7. Application of species sensitivity distribution in aquatic probabilistic ecological risk assessment of cypermethrin: a case study in an urban stream in South China.

    PubMed

    Li, Huizhen; You, Jing

    2015-03-01

    A tiered ecological risk assessment was applied to quantitatively refine the overall probabilistic risk of cypermethrin, a pyrethroid insecticide, to aquatic organisms. These results were then validated through the bioassays using field water from an urban stream, Chebei Creek in Guangzhou, South China. Seventeen water samples were collected along Chebei Creek for evaluation. In total, 71% of the field waters were acutely toxic to Hyallela azteca and 24% of the waters caused 100% mortality. Toxic unit evaluation suggested that cypermethrin was one of the main contributors to toxicity. The tiered ecological risk assessment approach (deterministic quotient method and probabilistic methods, including joint probability curve and Monte Carlo Simulation) suggested that cypermethrin posed significant threats to aquatic ecology in this stream. The overall probabilistic risk of cypermethrin to aquatic species in Chebei Creek reached 66% when acute-to-chronic ratios were set at 125. An exceedance probability of cypermethrin in Chebei Creek that affected H. azteca as modeled using the joint probability curve method was 88%, suggesting that most sites were at risk due to cypermethrin exposure. This value was similar to the results obtained from acute toxicity tests (71% of field water samples were acutely toxic to H. azteca), indicating the effectiveness of the tiered approach to assess risk of cypermethrin in urban waterways. To the authors' knowledge, the present study is the first to provide a focused probabilistic evaluation of ecological risk for cypermethrin in a complex urban waterway environment. Despite uncertainties existing in the ecological risk assessment procedure, this approach provides a comprehensive assessment of ecological risk of cypermethrin, and subsequently, a foundation for further risk diagnosis and management in urban waterways.

  8. A microcosm study to support aquatic risk assessment of nickel: Community-level effects and comparison with bioavailability-normalized species sensitivity distributions.

    PubMed

    Hommen, Udo; Knopf, Burkhard; Rüdel, Heinz; Schäfers, Christoph; De Schamphelaere, Karel; Schlekat, Chris; Garman, Emily Rogevich

    2016-05-01

    The aquatic risk assessment for nickel (Ni) in the European Union is based on chronic species sensitivity distributions and the use of bioavailability models. To test whether a bioavailability-based safe threshold of Ni (the hazardous concentration for 5% of species [HC5]) is protective for aquatic communities, microcosms were exposed to 5 stable Ni treatments (6-96 μg/L) and a control for 4 mo to assess bioaccumulation and effects on phytoplankton, periphyton, zooplankton, and snails. Concentrations of Ni in the periphyton, macrophytes, and snails measured at the end of the exposure period increased in a dose-dependent manner but did not indicate biomagnification. Abundance of phytoplankton and snails decreased in 48 μg Ni/L and 96 μg Ni/L treatments, which may have indirectly affected the abundance of zooplankton and periphyton. Exposure up to 24 μg Ni/L had no adverse effects on algae and zooplankton, whereas the rate of population decline of the snails at 24 μg Ni/L was significantly higher than in the controls. Therefore, the study-specific overall no-observed-adverse-effect concentration (NOAEC) is 12 μg Ni/L. This NOAEC is approximately twice the HC5 derived from a chronic species sensitivity distribution considering the specific water chemistry of the microcosm by means of bioavailability models. Thus, the present study provides support to the protectiveness of the bioavailability-normalized HC5 for freshwater communities.

  9. Meetings

    NASA Astrophysics Data System (ADS)

    As the first Meeting Chairman for the Spring and Fall meetings, Martin Walt has achieved notable success in realizing the many goals set forth by the Union for its annual meetings. Under his guidance, the Meeting Program Committee has been able to reduce the number of conflicting sessions and provide for the presentation of well-organized and effectively displayed poster sessions. The early planning of Union sessions and the introduction of ‘mini-frontiers,’ along with careful scheduling, has provided an increased opportunity for participation. A record high of 2785 registrants was recorded during the 1981 Fall Meeting, topping very slightly the old record of 2775 for the 1974 Spring Meeting.

  10. Species and biogeochemical cycles of organic phosphorus in sediments from a river with different aquatic plants located in Huaihe River Watershed, China.

    PubMed

    Yuan, He Zhong; Pan, Wei; Ren, Li Jun; Liu, Eeng Feng; Shen, Ji; Geng, Qi Fang; An, Shu Qing

    2015-01-01

    The results of phosphorus fractionation in the sediments from a contaminated river containing different aquatic plants, analyzed by solution 31P-NMR for Organic Phosphorus, showed that the concentration of Inorganic Phosphorus dominated in all species and Organic Phosphorus accounted for over 20% of Total Phosphorus. In general, orthophosphate was dominant in all the sampling sites. The proportion of Organic Phosphorus accounting for the Total Phosphorus in the sediments with different plant decreased in the following order: Paspalum distichum>Typha orientalis>Hydrilla verticillata. Phosphorus-accumulation ability of Paspalum distichum was obviously stronger than Typha orientalis and Hydrilla verticillata. The Organic Phosphorus was in aquatic plants dominated by humic-associated P (Hu-P), which converted to Inorganic Ohosphorus more significantly in submerged plants than in emerged plants. The sediment dominated by Paspalum distichum abundantly accumulated Organic Phosphorus in the orthophosphate monoester fraction. The degradation and mineralization of orthophosphate monoester was the important source of high Inorganic Phosphorus concentration and net primary productivity in Suoxu River. The Organic Phosphorus derived from Typha orientalis and Hydrilla verticillata was dramatically converted to Inorganic Phosphorus when the environmental factors varied.

  11. Induction of sporulation and the influence of time, temperature, and inoculum size on growth in two species of aquatic fungi (Saprolegniales)

    USGS Publications Warehouse

    Bailey, T.A.; Bradford, K.; Bland, C.E.

    1990-01-01

    Because the infective stage of most mycoses of aquatic organisms is the zoospore, we attempted to establish optimum conditions under which zoospores could be produced for use in antifungal testing. Optimum sporulation time, incubation time, inoculum size, and growth temperature were determined for each oftwo saprolegniaceous fungi, Achlya flagellata Coker and Saprolegnia hypogyna (Pringsheim) de Bary. Both species produced the largest number of zoospores after 18 hours (51.7 spores/ml for A. jlagellata and 848.0 spores/ml for S. hypogyna), and yielded maximum growth after 48 hours at 22 'C. The recommended test inoculum size for S. hypogyna (5,600 spores/ml was nearly three times that for A. flagellata (2,000 spores/ml),

  12. New species of aquatic insects from Europe (Insecta: Trichoptera): Alps and Pyrenees as harbours of unknown biodiversity

    PubMed Central

    GRAF, WOLFRAM; VITECEK, SIMON; PREVIŠIĆ, ANA; MALICKY, HANS

    2016-01-01

    New species are described from the following genera: Consorophylax and Anisogamus, (Trichoptera, Limnephilidae). Additionally the larvae of the genus Anisogamus, and the larval stages of Anisogamus waringeri nov. sp. and A. difformis (McLachlan 1867) are described. The new species Consorophylax vinconi sp. nov. is a microendemic from the Southern Alps and differs distinctly from its congeners in the shape of the parameres, which are distinctly straitened in the distal quarter in the new species. The new species Anisogamus waringeri sp. nov. represents the second species in the hitherto monospecific genus Anisogamus. Compared to Anisogamus difformis, A. waringeri sp. nov. develops more slender superior appendages; a more rounded basal plate of the intermediate appendages, lacking pointed protuberances; and parameres shorter than the aedaegus, proximally with one dorsal and several ventral tines. Further, the two species are disjunctly distributed in the European mountain ranges (A. difformis: Alps, A. waringeri sp. nov.: Pyrenees). Larvae of the genus Anisogamus are characterized by the lack of a dorsal protuberance on the 1st abdominal segment, a unique feature among Limnephilidae. Anisogamus difformis and A. waringeri sp. nov. larvae differ in pronotum shape. The recovery of two new species demonstrates the significance of taxonomic studies in Europe, and the importance of adequate training for young scientists in order to assess a biodiversity under threat of extinction that has yet to be fully described. PMID:25661619

  13. Prevalence of zoonotic bacteria in wild and farmed aquatic species and seafood: a scoping study, systematic review, and meta-analysis of published research.

    PubMed

    Tuševljak, Nataša; Rajić, Andrijana; Waddell, Lisa; Dutil, Lucie; Cernicchiaro, Natalia; Greig, Judy; Wilhelm, Barbara J; Wilkins, Wendy; Totton, Sarah; Uhland, F Carl; Avery, Brent; McEwen, Scott A

    2012-06-01

    Increased reliance on seafood has brought to light concerns regarding food safety, but the information to inform risk assessment or surveillance needs is lacking. A scoping study (ScS) was conducted to characterize published research investigating selected zoonotic bacteria and public health topics in various wild and farmed aquatic species and seafood. This was followed by a systematic review (SR) on selected bacteria (Aeromonas spp., generic Escherichia coli, Salmonella spp., and Vibrio spp.) and aquatic species (clams, mussels, oysters, salmon, and shrimp [including prawn]); a meta-analysis (MA) was conducted only at the retail level due to considerable variability among various pathogen/seafood combinations. The ScS revealed the most frequently investigated themes were farm-level prevalence and intervention research for Vibrio spp. and Aeromonas spp. Antimicrobial use (AMU) and the association between AMU and antimicrobial resistance were rarely investigated. The SR indicated a consistent lack of reporting regarding study methodology and results, precluding the use of many studies in and full benefits of MA. MA of Aeromonas, E. coli, and Salmonella prevalence in retail salmon resulted in pooled estimates of 13% (6-27%), 2% (0.1-11%), and 1% (0-5%), respectively. When MA of pathogen/seafood combination resulted in statistically significant heterogeneity (p<0.1), median/range were reported at the region level. The results from our ScS, SR, and MA could be used for better design of future bacteriological surveys of seafood and as inputs for risk assessments or surveillance initiatives in this field.

  14. Acute and chronic toxicity of tetrabromobisphenol A to three aquatic species under different pH conditions.

    PubMed

    He, Qun; Wang, Xinghao; Sun, Ping; Wang, Zunyao; Wang, Liansheng

    2015-07-01

    Tetrabromobisphenol A (TBBPA) is a well-known brominated flame retardant. It has been detected in the environment and shows high acute toxicity to different organisms at high concentrations. In this work, the effects of pH and dimethyl sulfoxide (DMSO) on the acute toxicity of TBBPA to Daphnia magna and Limnodrilus hoffmeisteri were tested, and the oxidative stress induced by TBBPA in livers of Carassius auratus was assessed using four biomarkers. The integrated biomarker response (IBR) was applied to assess the overall antioxidant status in fish livers. Moreover, fish tissues (gills and livers) were also studied histologically. The results showed that low pH and DMSO enhanced the toxicity of TBBPA. Furthermore, changes in the activity of antioxidant enzymes and glutathione level suggested that TBBPA generates oxidative stress in fish livers. The IBR index revealed that fish exposed to 3mg/L TBBPA experienced more serious oxidative stress than exposed to acidic or alkaline conditions. The histopathological analysis revealed lesions caused by TBBPA. This study provides valuable toxicological information of TBBPA and will facilitate a deeper understanding on its potential toxicity in realistic aquatic environments. PMID:25980965

  15. Acute and chronic toxicity of tetrabromobisphenol A to three aquatic species under different pH conditions.

    PubMed

    He, Qun; Wang, Xinghao; Sun, Ping; Wang, Zunyao; Wang, Liansheng

    2015-07-01

    Tetrabromobisphenol A (TBBPA) is a well-known brominated flame retardant. It has been detected in the environment and shows high acute toxicity to different organisms at high concentrations. In this work, the effects of pH and dimethyl sulfoxide (DMSO) on the acute toxicity of TBBPA to Daphnia magna and Limnodrilus hoffmeisteri were tested, and the oxidative stress induced by TBBPA in livers of Carassius auratus was assessed using four biomarkers. The integrated biomarker response (IBR) was applied to assess the overall antioxidant status in fish livers. Moreover, fish tissues (gills and livers) were also studied histologically. The results showed that low pH and DMSO enhanced the toxicity of TBBPA. Furthermore, changes in the activity of antioxidant enzymes and glutathione level suggested that TBBPA generates oxidative stress in fish livers. The IBR index revealed that fish exposed to 3mg/L TBBPA experienced more serious oxidative stress than exposed to acidic or alkaline conditions. The histopathological analysis revealed lesions caused by TBBPA. This study provides valuable toxicological information of TBBPA and will facilitate a deeper understanding on its potential toxicity in realistic aquatic environments.

  16. 76 FR 34746 - Species Proposals for Consideration at the Sixteenth Regular Meeting of the Conference of the...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-06-14

    ... Endangered Species of Wild Fauna and Flora (CITES or the Convention) at the upcoming sixteenth meeting of the... ] Fauna and Flora, hereinafter referred to as CITES or the Convention, is an international treaty designed... Conference of the Parties to the Convention on International Trade in Endangered Species of Wild Fauna...

  17. Species-specific patterns of swimming escape performance and cholinesterase activity in a guild of aquatic insects exposed to endosulfan.

    PubMed

    Trekels, Hendrik; Van de Meutter, Frank; Stoks, Robby

    2012-04-01

    Next to imposing direct lethal effects, pollutants may also indirectly impose mortality by making prey organisms more vulnerable to predation. We report that four water boatmen species differed strongly in direct endosulfan-imposed mortality, and only the species that suffered highest mortality, Sigara iactans, also showed a reduction in escape swimming speed. While head AChE activity was inhibited in all four species, body ChE was only inhibited in S. iactans where it covaried with escape swimming speed, indicating a mechanistic link between body ChE and swimming speed. Our study underscores the need for risk assessment to consider sublethal pollutant effects, which may considerably affect survival rates under natural conditions, also when testing concentrations of a pesticide that cause direct mortality. Such sublethal effects may generate discrepancies between laboratory and field studies and should be considered when designing safety factors for toxicants where the risk assessment is solely based on LC50 values.

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

    PubMed

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

    2014-09-01

    Effective, species-specific zebra mussel control is needed urgently for Ireland׳s freshwater bodies, which became infested with non-native zebra mussels in the 1990s. Zequanox®, a newly commercialized product for zebra and quagga mussel control, is composed of dead Pseudomonas fluorescens CL 145A cells. This paper describes ecotoxicology tests on three representative native Irish freshwater species: Anodonta (duck mussel), Chironomus plumosus (non-biting midge), and Austropotamobius pallipes (white-clawed crayfish). The species were exposed to Zequanox in a 72-h static renewal toxicity test at concentrations of 100-750mg active ingredient per liter (mga.i./L). Water quality parameters were measured every 12-24h before and after water and product renewal. After 72h, endpoints were reported as LC10, LC50, and LC100. The LC50 values derived were (1) Anodonta: ≥500mga.i./L (2) C. plumosus: 1075mga.i./L, and (3) A. pallipes: ≥750mga.i./L. These results demonstrate that Zequanox does not negatively affect these organisms at the concentration required for >80percent zebra mussel mortality (150mg a.i/L) and the maximum allowable treatment concentration in the United Sates (200mga.i./L). They also show the overall species-specificity of Zequanox, and support its use in commercial facilities and open waters. PMID:24927392

  19. Cytogenetics analysis and testis morphology of aquatic species of the families Belostomatidae, Gelastocoridae, Gerridae, Notonectidae, and Veliidae (Heteroptera).

    PubMed

    Vicente Pereira, Luis Lenin; Chaboli Alevi, Kaio Cesar; Urbanin Castanhole, Márcia Maria; Figueiredo Moreira, Felipe Ferraz; Freires Barbosa, Julianna; Massumi Itoyama, Mary

    2015-01-01

    The Heteroptera have holocentric chromosomes with kinetic activity restricted to the end of chromosomes. The first meiotic division is reductional for the autosomes and equational for the sexual. Only a few species of this suborder have been analyzed. In this study, we observed the morphologies of the testes of the Heteroptera species Belostoma anurum (Herrich-Schäffer, 1948), Belostoma micantulum (Stal, 1858), Gelastocoris angulatus (Melin, 1929), Gelastocoris flavus flavus (Guérin-Méneville, 1844), Rheumatobates crassifemur crassifemur (Esaki, 1926), Buenoa amnigenus (White, 1879), Buenoa unguis (Truxal, 1953), Martarega brasiliensis (Truxal, 1949), Martarega membranácea (White, 1879), Martarega uruguayensis (Berg, 1883), Rhagovelia tenuipes (Champion, 1898) and Rhagovelia zela (Drake, 1959). We found that the testes of these species can be round, round/spiral, or elongated/spiral. The size of the prophase I cells was found to vary, with the smallest ones being detected in B. micantulum and Rha. zela, the largest in G. f. flavus, and ones of intermediate size in R. c. crassifemur and M. brasiliensis. With respect to the chromosome complement, we verified the presence of 2n =  16: (14A+XY, B. micantulum and G. angulatus), 21: (20A+X0, R. c. crassifemur), 23: (22A+X0, Rha. zela and Rha. tenuipes), 25: (24A+X0, Bu. amnigenus and Bu. unguis; 22A+2m+X0, M. membranacea), 27: (24A+2m+X0, M. brasiliensis and M. uruguayensis), 29: (26A+X1X2Y, B. anurum), and 35: (30A+X1X2X3X4Y, G. f. flavus). We found that the features of spermatogenesis in these species are similar to those of other previously described Heteroptera species, differing only in testicular morphology, chromosome number, and sex chromosome system. PMID:25797798

  20. Whole effluent toxicity assessment at a wastewater treatment plant upgraded with a full-scale post-ozonation using aquatic key species.

    PubMed

    Magdeburg, Axel; Stalter, Daniel; Oehlmann, Jörg

    2012-08-01

    Ozonation as final wastewater (WW) polishing step, following conventional activated sludge treatment is increasingly implemented in sewage treatment for contaminant degradation to prevent surface water pollution. While the oxidative degradation of chemicals has been extensively investigated, the in vivo toxicological characteristics of ozonated whole effluents are rarely a matter of research. In the present study, whole effluents were toxicologically evaluated with an in vivo test battery before and after full-scale ozonation and subsequent sand filtration on site at a treatment plant. One aquatic plant (duckweed, Lemna minor) and five invertebrate species of different systematic groups (Lumbriculus variegatus, Chironomus riparius, Potamopyrgus antipodarum, Daphnia magna) were exposed to the effluents in a flow-through-designed test system with a test duration of 7-28 d. None of the considered toxicity endpoints correlated with the pollutant elimination. A tendency towards an increased toxicity after ozonation was apparent in three of the test systems showing [statistically] significant adverse effects in the L. variegatus toxicity test (decrease in reproduction and biomass). After sand filtration, adverse effects were reduced to a similar level like after conventional treatment. Solely the Daphnia reproduction test revealed beneficial effects after ozonation in combination with sand filtration. Results of the test battery indicate the formation of adverse oxidation products during WW ozonation. L. variegatus appeared to be the most sensitive of the five test species. Sand filtration effectively removes or detoxifies toxic oxidation products, as toxic effects were subsequently reduced to the level after conventional treatment. PMID:22560180

  1. Subfossils of extinct and extant species of Simuliidae (Diptera) from Austral and Cook Islands (Polynesia): anthropogenic extirpation of an aquatic insect?

    PubMed

    Craig, Douglas A; Porch, Nick

    2013-01-01

    Subfossil head capsules of Simuliidae larvae have been recovered from swamps on Tubuai and Raivavae of the Austral Islands, and Atiu and Mangaia of the southern Cook Islands. For Tubuai and Raivavae it is likely that the simuliids are extinct, but a single simuliid species is extant on nearby Rurutu. For Atiu and Mangaia, extant simuliids have not been reported, but are known on Rarotonga. Well-preserved head capsules indicate that the Cook Islands subfossils are those of Sinulitin (Inseliellumn) teruananga Craig and Craig, 1986. For the Austral Islands, the simuliid from Tubuai is considered a variant of Simudiunt (Inseliellumn) rurutuense Craig and Joy, 2000. That from Raivavae is morphologically distinct and is described here as a new species, Simuliun (Inseliellumn) raivavaense Craig and Porch. Humans arrived in Eastern Polynesia ca. 1,000 years ago resulting in the widespread destruction of lowland forest and conversion of wetlands to agriculture with implied consequences for the indigenous biota of these habitats. Here we consider that one such result was loss of freshwater aquatic biodiversity. PMID:26287098

  2. Whole effluent toxicity assessment at a wastewater treatment plant upgraded with a full-scale post-ozonation using aquatic key species.

    PubMed

    Magdeburg, Axel; Stalter, Daniel; Oehlmann, Jörg

    2012-08-01

    Ozonation as final wastewater (WW) polishing step, following conventional activated sludge treatment is increasingly implemented in sewage treatment for contaminant degradation to prevent surface water pollution. While the oxidative degradation of chemicals has been extensively investigated, the in vivo toxicological characteristics of ozonated whole effluents are rarely a matter of research. In the present study, whole effluents were toxicologically evaluated with an in vivo test battery before and after full-scale ozonation and subsequent sand filtration on site at a treatment plant. One aquatic plant (duckweed, Lemna minor) and five invertebrate species of different systematic groups (Lumbriculus variegatus, Chironomus riparius, Potamopyrgus antipodarum, Daphnia magna) were exposed to the effluents in a flow-through-designed test system with a test duration of 7-28 d. None of the considered toxicity endpoints correlated with the pollutant elimination. A tendency towards an increased toxicity after ozonation was apparent in three of the test systems showing [statistically] significant adverse effects in the L. variegatus toxicity test (decrease in reproduction and biomass). After sand filtration, adverse effects were reduced to a similar level like after conventional treatment. Solely the Daphnia reproduction test revealed beneficial effects after ozonation in combination with sand filtration. Results of the test battery indicate the formation of adverse oxidation products during WW ozonation. L. variegatus appeared to be the most sensitive of the five test species. Sand filtration effectively removes or detoxifies toxic oxidation products, as toxic effects were subsequently reduced to the level after conventional treatment.

  3. Physical Non-Contact Communication between Microscopic Aquatic Species: Novel Experimental Evidences for an Interspecies Information Exchange.

    PubMed

    Fels, Daniel

    2016-01-01

    Previous experiments on physical non-contact communication within same species gave rise to test for this type of communication also across the species border, which was the aim of the present study. It was found that autotrophic unicellular organisms (Euglena viridis), separated by cuvettes, affected the proliferation rate of heterotrophic unicellular organisms (Paramecium caudatum). Further, the heterotrophic unicellular organism affected also the proliferation rate of a multicellular heterotrophic organism (Rotatoria sp.) and vice versa. In the case when populations (of Euglena viridis and Paramecium caudatum) were shielded against electromagnetic fields in the optical spectrum from each other, no effects were measured. The results may support the notion that the organisation of ecosystems relies also on the exchange of electromagnetic fields from their constituting biosystems. PMID:27042178

  4. Physical Non-Contact Communication between Microscopic Aquatic Species: Novel Experimental Evidences for an Interspecies Information Exchange

    PubMed Central

    2016-01-01

    Previous experiments on physical non-contact communication within same species gave rise to test for this type of communication also across the species border, which was the aim of the present study. It was found that autotrophic unicellular organisms (Euglena viridis), separated by cuvettes, affected the proliferation rate of heterotrophic unicellular organisms (Paramecium caudatum). Further, the heterotrophic unicellular organism affected also the proliferation rate of a multicellular heterotrophic organism (Rotatoria sp.) and vice versa. In the case when populations (of Euglena viridis and Paramecium caudatum) were shielded against electromagnetic fields in the optical spectrum from each other, no effects were measured. The results may support the notion that the organisation of ecosystems relies also on the exchange of electromagnetic fields from their constituting biosystems. PMID:27042178

  5. At random meetings to the creation of new species of Salamander

    NASA Astrophysics Data System (ADS)

    Brillant, Marie-Pierre

    2013-04-01

    The pupils in final year of high school (15-18 years old) study the notion "species" and the creation of new species in various ways. Having studied genetic admixtures, this activity allows the pupils to build a scenario explaining the creation of a new species of Salamander in southern California from an ancestral population existing in northern Oregon. They can observe, on Google Earth, various populations of Salamander of the genus Ensatina. Salamanders of the genus Ensatina live in California around the Joaquin and Sacramento dry valleys. In this software, the pupils get information about the salamanders' environment and photographs of individuals and environments. During a migratory movement toward new territories to be colonized, these salamanders meet an inhospitable environment that they can not occupy. This population then splits up into two migratory branches, east and west, each overcoming the obstacles in different ways. The two groups gradually colonized southern territories but they avoided the too dry and hot San Joaquin plains. The two main branches of the original population gradually move away from each other, and genetic exchanges between them decrease over time. Eventually, we can find various populations of Salamander on both sides of the valleys, since the salamanders occupied new territories and diversified along the way. Among mutations that randomly occur, only those mutations that are best adapted in the origin were conserved in the genetic heritage of every population. When the individuals stemming from different western populations met, they were interfertile and give fertile hybrids, which was verified in the laboratory. Likewise, when individuals of the different eastern subspecies met accidentally, fertile hybrids also could arise from these crossings. The pupils can observe what happens in the overlap of various populations : interfertility or not. They also have geological, geographical and climatic information about the San Joaquin

  6. Aquatic Species Responses to Changes in Streamflow and Stream Temperature in the Willamette River Basin of Oregon

    NASA Astrophysics Data System (ADS)

    Chang, H.; Psaris, A. M.; Strecker, A.

    2014-12-01

    Climate models project less summer precipitation and hotter temperatures in the Pacific Northwest. These changes will bring earlier snowmelt and reduced summer flow, which will increase stream temperature. Many cold water species will be adversely affected by such changes. However, the spatial and temporal extent of how each stream responds to climate change and how fish species respond to varying degrees of changes in flow and stream temperature across multiple streams has not been thoroughly studied. Using a combination of representative downscaled climate data, a watershed hydrologic model, and regression analysis, we projected future changes in streamflow and temperature and the responses of fish habitat to these changes for several tributaries of the Willamette River basin that exhibits distinct hydrologic landscape regions. Our simulation results suggest that streams located in the High Cascades where groundwater input is high will experience less warming and less flow reduction, thus more resilient to warming. In contrast, streams in transient areas where snow cover is projected to decline substantially will experience the most declines in fish diversity as a result of reduction in flow and highest rise in stream temperature. Our results suggest spatially targeted adaptive management strategies for fishes in a large heterogeneous river basin will be necessary in a rapidly changing climate.

  7. Induction of a C(4)-like mechanism of CO(2) fixation in Egeria densa, a submersed aquatic species.

    PubMed

    Casati, P; Lara, M V; Andreo, C S

    2000-08-01

    The expression of phosphoenolpyruvate carboxylase (PEPC) and NADP-malic enzyme (NADP-ME) in Egeria densa leaves was studied under low temperature and light (LTL) following incubation under high temperature and light (HTL), conditions previously shown to induce high and low CO(2) compensation points, respectively. Transfer from LTL to HTL conditions induced increases in the activities and amounts of both enzymes. One NADP-ME isoform was observed in induced and uninduced samples. Two isoforms of PEPC were expressed, with the lower M(r) isoform being induced by HTL. NADP-ME showed properties similar to those of the isoform in C(3) species. The inducible PEPC isoform has a low K(m) for both substrates. PEPC kinetic and regulatory properties (V(max) and K(m) for phosphoenolpyruvate, and I(50) for L-malate) are different in samples taken in the dark from those in the light, indicating that some modification of PEPC may be occurring during the day. Finally, abscisic acid induced the expression of PEPC and NADP-ME in a manner similar to temperature induction, except that the activities of both PEPC isoforms were increased. A different signaling system may exist in this species in response to high temperature or abscisic acid, both of which induce changes in photosynthetic metabolism. PMID:10938377

  8. Aquatic Sediments.

    ERIC Educational Resources Information Center

    Sanville, W. D.; And Others

    1978-01-01

    Presents a literature review of aquatic sediments and its effect upon water quality, covering publications of 1976-77. This review includes: (1) sediment water interchange; (2) chemical and physical characterization; and (3) heavy water in sediments. A list of 129 references is also presented. (HM)

  9. Examining the joint toxicity of chlorpyrifos and atrazine in the aquatic species: Lepomis macrochirus, Pimephales promelas and Chironomus tentans.

    PubMed

    Tyler Mehler, W; Schuler, Lance J; Lydy, Michael J

    2008-03-01

    The joint toxicity of chlorpyrifos and atrazine was compared to that of chlorpyrifos alone to discern any greater than additive response using both acute toxicity testing and whole-body residue analysis. In addition, acetylcholinesterase (AChE) inhibition and biotransformation were investigated to evaluate the toxic mode of action of chlorpyrifos in the presence of atrazine. The joint toxicity of atrazine and chlorpyrifos exhibited no significant difference in Lepomis macrochirus compared to chlorpyrifos alone; while studies performed with Pimephales promelas and Chironomus tentans, did show significant differences. AChE activity and biotransformation showed no significant differences between the joint toxicity of atrazine and chlorpyrifos and that of chlorpyrifos alone. From the data collected, the combination of atrazine and chlorpyrifos pose little additional risk than that of chlorpyrifos alone to the tested fish species.

  10. Comparative toxicity of eight oil dispersants, Louisiana sweet crude oil (LSC), and chemically dispersed LSC to two aquatic test species.

    PubMed

    Hemmer, Michael J; Barron, Mace G; Greene, Richard M

    2011-10-01

    The present study describes the acute toxicity of eight commercial oil dispersants, South Louisiana sweet crude oil (LSC), and chemically dispersed LSC. The approach used consistent test methodologies within a single laboratory in assessing the relative acute toxicity of the eight dispersants, including Corexit 9500A, the predominant dispersant applied during the DeepWater Horizon spill in the Gulf of Mexico. Static acute toxicity tests were performed using two Gulf of Mexico estuarine test species, the mysid shrimp (Americamysis bahia) and the inland silversides (Menidia beryllina). Dispersant-only test solutions were prepared with high-energy mixing, whereas water-accommodated fractions of LSC and chemically dispersed LSC were prepared with moderate energy followed by settling and testing of the aqueous phase. The median lethal concentration (LC50) values for the dispersant-only tests were calculated using nominal concentrations, whereas tests conducted with LSC alone and dispersed LSC were based on measured total petroleum hydrocarbon (TPH) concentrations. For all eight dispersants in both test species, the dispersants alone were less toxic (LC50s: 2.9 to >5,600 µl/L) than the dispersant-LSC mixtures (0.4-13 mg TPH/L). Louisiana sweet crude oil alone had generally similar toxicity to A. bahia (LC50: 2.7 mg TPH/L) and M. beryllina (LC50: 3.5 mg TPH/L) as the dispersant-LSC mixtures. The results of the present study indicate that Corexit 9500A had generally similar toxicity to other available dispersants when tested alone but was generally less toxic as a mixture with LSC. PMID:21766318

  11. Comparative toxicity of eight oil dispersants, Louisiana sweet crude oil (LSC), and chemically dispersed LSC to two aquatic test species.

    PubMed

    Hemmer, Michael J; Barron, Mace G; Greene, Richard M

    2011-10-01

    The present study describes the acute toxicity of eight commercial oil dispersants, South Louisiana sweet crude oil (LSC), and chemically dispersed LSC. The approach used consistent test methodologies within a single laboratory in assessing the relative acute toxicity of the eight dispersants, including Corexit 9500A, the predominant dispersant applied during the DeepWater Horizon spill in the Gulf of Mexico. Static acute toxicity tests were performed using two Gulf of Mexico estuarine test species, the mysid shrimp (Americamysis bahia) and the inland silversides (Menidia beryllina). Dispersant-only test solutions were prepared with high-energy mixing, whereas water-accommodated fractions of LSC and chemically dispersed LSC were prepared with moderate energy followed by settling and testing of the aqueous phase. The median lethal concentration (LC50) values for the dispersant-only tests were calculated using nominal concentrations, whereas tests conducted with LSC alone and dispersed LSC were based on measured total petroleum hydrocarbon (TPH) concentrations. For all eight dispersants in both test species, the dispersants alone were less toxic (LC50s: 2.9 to >5,600 µl/L) than the dispersant-LSC mixtures (0.4-13 mg TPH/L). Louisiana sweet crude oil alone had generally similar toxicity to A. bahia (LC50: 2.7 mg TPH/L) and M. beryllina (LC50: 3.5 mg TPH/L) as the dispersant-LSC mixtures. The results of the present study indicate that Corexit 9500A had generally similar toxicity to other available dispersants when tested alone but was generally less toxic as a mixture with LSC.

  12. Silver nanoparticles induced accumulation of reactive oxygen species and alteration of antioxidant systems in the aquatic plant Spirodela polyrhiza.

    PubMed

    Jiang, Hong-Sheng; Qiu, Xiao-Ni; Li, Gen-Bao; Li, Wei; Yin, Li-Yan

    2014-06-01

    Silver nanoparticles (AgNPs) are widely used commercially because of their antibacterial properties. Oxidative stress is known to be involved in the toxicity of AgNPs to bacteria, animals, and algae. The authors used Spirodela polyrhiza to investigate whether AgNPs can induce oxidative stress in higher plants. Results showed that there was a dose-dependent increase in levels of reactive oxygen species, superoxide dismutase and peroxidase activity, and the antioxidant glutathione content in 6-nm AgNP treatments. Catalase activity and malondialdehyde content in 6-nm AgNP treatments was significantly higher than the control at silver concentrations of 5 mg L(-1) . Superoxide dismutase and catalase activity and antioxidant glutathione and malondialdehyde content were not significantly different at 10 mg L(-1) of AgNPs (6 nm and 20 nm). Treatment with 20 µg L(-1) Ag(+) (the amount almost equal to 10 mg L(-1) AgNPs released) did not change the reactive oxygen species level or antioxidant enzymes activity. Micron-sized Ag particles had no effect on S. polyrhiza. Transmission electron microscopy showed that, compared with the control, chloroplasts in S. polyrhiza treated with 6-nm and 20-nm AgNPs accumulated starch grains and had reduced intergranal thylakoids. These results clearly indicate that AgNPs are able to cause oxidative stress and affect the chloroplast structure and function of S. polyrhiza, and this effect was not caused by Ag(+) released from particles. PMID:24619507

  13. Theoretical dietary modelling of Australian seafood species to meet long-chain omega 3 fatty acid dietary recommendations

    PubMed Central

    Grieger, Jessica A.; McLeod, Catherine; Chan, Lily; Miller, Michelle D.

    2013-01-01

    Background Several agencies recommend seafood to be consumed 2–3 times per week. In Australia, there is a lack of nutrient composition data for seafood species and it is not known whether including different seafood species in a diet would provide sufficient long-chain omega 3 fatty acids (LC n–3 PUFA) to meet various national recommendations. Objective To utilise recent nutrient composition data for major Australian seafood groups (n=24) with the addition of two tuna options (total n=26) to: (1) determine whether including these species into a diet based on the Australian Guide to Healthy Eating (AGHE) will achieve LC n–3 PUFA recommendations [Adequate Intake (AI: 160 mg/d men, 90 mg/d women)], Suggested Dietary Target (SDT), 500 mg/d Heart Foundation (HF) recommendation and (2) determine the weekly number of servings of seafood to meet recommendations using either lower fat (n=23, <10% total fat) or higher fat (n=3, ≥10% total fat) seafood. Design Two simulation models incorporated all 26 species of seafood or only lower fat seafood into a diet based on the AGHE. Two further models identified the number of servings of lower or higher fat seafood required to meet recommendations. Results Including 2 and 3 servings/week of any seafood would enable 89% of women and 66% of men to meet the AI. Including only lower fat seafood would enable 83% of women and 47% of men to meet the AI. Half a serving/week of higher fat seafood would enable 100% of men and women to meet the AI. Conclusions Including the recommended 2–3 servings of seafood/week requires at least some higher fat seafood to be consumed in order for most men and women to meet the AI. Further messages and nutrition resources are needed which provide options on how to increase intake of LC n–3 PUFA, specifically through consumption of the higher fat seafood. PMID:24179469

  14. Effects of changing climate on aquatic habitat and connectivity for remnant populations of a wide-ranging frog species in an arid landscape

    USGS Publications Warehouse

    Pilliod, David S.; Arkle, Robert S.; Robertson, Jeanne M; Murphy, Melanie; Funk, W. Chris

    2015-01-01

    Amphibian species persisting in isolated streams and wetlands in desert environments can be susceptible to low connectivity, genetic isolation, and climate changes. We evaluated the past (1900–1930), recent (1981–2010), and future (2071–2100) climate suitability of the arid Great Basin (USA) for the Columbia spotted frog (Rana luteiventris) and assessed whether changes in surface water may affect connectivity for remaining populations. We developed a predictive model of current climate suitability and used it to predict the historic and future distribution of suitable climates. We then modeled changes in surface water availability at each time period. Finally, we quantified connectivity among existing populations on the basis of hydrology and correlated it with interpopulation genetic distance. We found that the area of the Great Basin with suitable climate conditions has declined by approximately 49% over the last century and will likely continue to decline under future climate scenarios. Climate conditions at currently occupied locations have been relatively stable over the last century, which may explain persistence at these sites. However, future climates at these currently occupied locations are predicted to become warmer throughout the year and drier during the frog's activity period (May – September). Fall and winter precipitation may increase, but as rain instead of snow. Earlier runoff and lower summer base flows may reduce connectivity between neighboring populations, which is already limited. Many of these changes could have negative effects on remaining populations over the next 50–80 years, but milder winters, longer growing seasons, and wetter falls might positively affect survival and dispersal. Collectively, however, seasonal shifts in temperature, precipitation, and stream flow patterns could reduce habitat suitability and connectivity for frogs and possibly other aquatic species inhabiting streams in this arid region.

  15. Effects of changing climate on aquatic habitat and connectivity for remnant populations of a wide-ranging frog species in an arid landscape.

    PubMed

    Pilliod, David S; Arkle, Robert S; Robertson, Jeanne M; Murphy, Melanie A; Funk, W Chris

    2015-09-01

    Amphibian species persisting in isolated streams and wetlands in desert environments can be susceptible to low connectivity, genetic isolation, and climate changes. We evaluated the past (1900-1930), recent (1981-2010), and future (2071-2100) climate suitability of the arid Great Basin (USA) for the Columbia spotted frog (Rana luteiventris) and assessed whether changes in surface water may affect connectivity for remaining populations. We developed a predictive model of current climate suitability and used it to predict the historic and future distribution of suitable climates. We then modeled changes in surface water availability at each time period. Finally, we quantified connectivity among existing populations on the basis of hydrology and correlated it with interpopulation genetic distance. We found that the area of the Great Basin with suitable climate conditions has declined by approximately 49% over the last century and will likely continue to decline under future climate scenarios. Climate conditions at currently occupied locations have been relatively stable over the last century, which may explain persistence at these sites. However, future climates at these currently occupied locations are predicted to become warmer throughout the year and drier during the frog's activity period (May - September). Fall and winter precipitation may increase, but as rain instead of snow. Earlier runoff and lower summer base flows may reduce connectivity between neighboring populations, which is already limited. Many of these changes could have negative effects on remaining populations over the next 50-80 years, but milder winters, longer growing seasons, and wetter falls might positively affect survival and dispersal. Collectively, however, seasonal shifts in temperature, precipitation, and stream flow patterns could reduce habitat suitability and connectivity for frogs and possibly other aquatic species inhabiting streams in this arid region.

  16. Acute toxicity of sodium bicarbonate, a major component of coal bed natural gas produced waters, to 13 aquatic species as defined in the laboratory

    USGS Publications Warehouse

    Harper, David D.; Farag, Aida M.; Skaar, Don

    2014-01-01

    Water produced during coal bed natural gas (CBNG) extraction in the Powder River Structural Basin of Wyoming and Montana (USA) may contain concentrations of sodium bicarbonate (NaHCO3) of more than 3000 mg/L. The authors evaluated the acute toxicity of NaHCO3, also expressed as bicarbonate (HCO3−), to 13 aquatic organisms. Of the 13 species tested, 7 had a median lethal concentration (LC50) less than 2000 mg/L NaHCO3, or 1300 mg/L HCO3−. The most sensitive species were Ceriodaphnia dubia, freshwater mussels (Lampsilis siliquoidea), pallid sturgeon (Scaphirhynchus albus), and shovelnose sturgeon (Scaphirhynchus platorynchus). The respective LC50s were 989 mg/L, 1120 mg/L, 1249 mg/L, and 1430 mg/L NaHCO3, or 699 mg/L, 844 mg/L, 831 mg/L, and 1038 mg/L HCO3−. Age affected the sensitivity of fathead minnows, even within life stage. Two days posthatch, fathead minnows were more sensitive to NaHCO3 and HCO3− compared with 4-d-old fish, even though fish up to 14 d old are commonly used for toxicity evaluations. The authors recommend that ion toxicity exposures be conducted with organisms less than 24 h posthatch to ensure that experiments document the most sensitive stage of development. The results of the present study, along with historical and current research regarding the toxicity of bicarbonate, may be useful to establish regulatory standards for HCO3−.

  17. Acute toxicity of sodium bicarbonate, a major component of coal bed natural gas produced waters, to 13 aquatic species as defined in the laboratory.

    PubMed

    Harper, David D; Farag, Aïda M; Skaar, Don

    2014-03-01

    Water produced during coal bed natural gas (CBNG) extraction in the Powder River Structural Basin of Wyoming and Montana (USA) may contain concentrations of sodium bicarbonate (NaHCO3) of more than 3000 mg/L. The authors evaluated the acute toxicity of NaHCO3, also expressed as bicarbonate (HCO3(-)), to 13 aquatic organisms. Of the 13 species tested, 7 had a median lethal concentration (LC50) less than 2000 mg/L NaHCO3, or 1300 mg/L HCO3(-). The most sensitive species were Ceriodaphnia dubia, freshwater mussels (Lampsilis siliquoidea), pallid sturgeon (Scaphirhynchus albus), and shovelnose sturgeon (Scaphirhynchus platorynchus). The respective LC50s were 989 mg/L, 1120 mg/L, 1249 mg/L, and 1430 mg/L NaHCO3, or 699 mg/L, 844 mg/L, 831 mg/L, and 1038 mg/L HCO3(-). Age affected the sensitivity of fathead minnows, even within life stage. Two days posthatch, fathead minnows were more sensitive to NaHCO3 and HCO3(-) compared with 4-d-old fish, even though fish up to 14 d old are commonly used for toxicity evaluations. The authors recommend that ion toxicity exposures be conducted with organisms less than 24 h posthatch to ensure that experiments document the most sensitive stage of development. The results of the present study, along with historical and current research regarding the toxicity of bicarbonate, may be useful to establish regulatory standards for HCO3(-). This article is a US Government work and is in the public domain in the USA.

  18. Effects of changing climate on aquatic habitat and connectivity for remnant populations of a wide-ranging frog species in an arid landscape.

    PubMed

    Pilliod, David S; Arkle, Robert S; Robertson, Jeanne M; Murphy, Melanie A; Funk, W Chris

    2015-09-01

    Amphibian species persisting in isolated streams and wetlands in desert environments can be susceptible to low connectivity, genetic isolation, and climate changes. We evaluated the past (1900-1930), recent (1981-2010), and future (2071-2100) climate suitability of the arid Great Basin (USA) for the Columbia spotted frog (Rana luteiventris) and assessed whether changes in surface water may affect connectivity for remaining populations. We developed a predictive model of current climate suitability and used it to predict the historic and future distribution of suitable climates. We then modeled changes in surface water availability at each time period. Finally, we quantified connectivity among existing populations on the basis of hydrology and correlated it with interpopulation genetic distance. We found that the area of the Great Basin with suitable climate conditions has declined by approximately 49% over the last century and will likely continue to decline under future climate scenarios. Climate conditions at currently occupied locations have been relatively stable over the last century, which may explain persistence at these sites. However, future climates at these currently occupied locations are predicted to become warmer throughout the year and drier during the frog's activity period (May - September). Fall and winter precipitation may increase, but as rain instead of snow. Earlier runoff and lower summer base flows may reduce connectivity between neighboring populations, which is already limited. Many of these changes could have negative effects on remaining populations over the next 50-80 years, but milder winters, longer growing seasons, and wetter falls might positively affect survival and dispersal. Collectively, however, seasonal shifts in temperature, precipitation, and stream flow patterns could reduce habitat suitability and connectivity for frogs and possibly other aquatic species inhabiting streams in this arid region. PMID:26445654

  19. Biomonitoring of aquatic systems.

    PubMed

    Kurelec, B; Gupta, R C

    1993-01-01

    The 32P-postlabelling analysis provides a sensitive means for detecting pollution-related DNA adducts in aquatic organisms exposed to environmental carcinogens. However, the following factors need to be taken into consideration during the data interpretation: (1) species-specific, naturally occurring DNA modifications (or I-compounds) are found in aquatic organisms at levels which are highly season-dependent; and (2) many aquatic organisms, particularly lower invertebrates, cannot form DNA adducts from common pollutants such as polycyclic aromatic hydrocarbons (PAHs). The level of natural adducts is especially high in lower invertebrates, such as sponges and sea-urchins during their reproductive phase in the spring time (March/April): in subsequent months adducts were either undetectable or present at only trace levels. These invertebrates do not metabolize PAHs such as benzo[a]pyrene but readily biotransform aromatic amines such as 2-acetylaminofluorene to DNA-reactive forms. Pollution-related DNA adducts have been found in fish living in highly polluted rivers and marine sites and in carp exposed to an artificial Diesel-2/crude oil slick. In certain fish (English sole, brown bullheads, etc.) living in polluted environments, the formation of pollution-related DNA adducts has been correlated with an increased incidence of tumours. It is concluded that, while DNA adducts detected in aquatic organisms can be used for biomonitoring and detecting pollutants, there are several confounding factors that should be taken into consideration before one attempts to determine the type and concentration of carcinogenic pollutants present in aquatic environments.

  20. DNA barcodes for assessment of the biological integrity of aquatic ecosystems

    EPA Science Inventory

    Water quality regulations and aquatic ecosystem monitoring increasingly rely on direct assessments of biological integrity. Because these aquatic “bioassessments” evaluate the incidence and abundance of sensitive aquatic species, they are able to measure cumulative ecosystem eff...

  1. Monitoring to assess progress toward meeting the Assabet River, Massachusetts, phosphorus total maximum daily load - Aquatic macrophyte biomass and sediment-phosphorus flux

    USGS Publications Warehouse

    Zimmerman, Marc J.; Qian, Yu; Yong Q., Tian

    2011-01-01

    In 2004, the Total Maximum Daily Load (TMDL) for Total Phosphorus in the Assabet River, Massachusetts, was approved by the U.S. Environmental Protection Agency. The goal of the TMDL was to decrease the concentrations of the nutrient phosphorus to mitigate some of the instream ecological effects of eutrophication on the river; these effects were, for the most part, direct consequences of the excessive growth of aquatic macrophytes. The primary instrument effecting lower concentrations of phosphorus was to be strict control of phosphorus releases from four major wastewatertreatment plants in Westborough, Marlborough, Hudson, and Maynard, Massachusetts. The improvements to be achieved from implementing this control were lower concentrations of total and dissolved phosphorus in the river, a 50-percent reduction in aquatic-plant biomass, a 30-percent reduction in episodes of dissolved oxygen supersaturation, no low-flow dissolved oxygen concentrations less than 5.0 milligrams per liter, and a 90-percent reduction in sediment releases of phosphorus to the overlying water. In 2007, the U.S. Geological Survey, in cooperation with the Massachusetts Department of Environmental Protection, initiated studies to evaluate conditions in the Assabet River prior to the upgrading of wastewater-treatment plants to remove more phosphorus from their effluents. The studies, completed in 2008, implemented a visual monitoring plan to evaluate the extent and biomass of the floating macrophyte Lemna minor (commonly known as lesser duckweed) in five impoundments and evaluated the potential for phosphorus flux from sediments in impounded and free-flowing reaches of the river. Hydrologically, the two study years 2007 and 2008 were quite different. In 2007, summer streamflows, although low, were higher than average, and in 2008, the flows were generally higher than in 2007. Visually, the effects of these streamflow differences on the distribution of Lemna were obvious. In 2007, large amounts of

  2. Pain in aquatic animals.

    PubMed

    Sneddon, Lynne U

    2015-04-01

    Recent developments in the study of pain in animals have demonstrated the potential for pain perception in a variety of wholly aquatic species such as molluscs, crustaceans and fish. This allows us to gain insight into how the ecological pressures and differential life history of living in a watery medium can yield novel data that inform the comparative physiology and evolution of pain. Nociception is the simple detection of potentially painful stimuli usually accompanied by a reflex withdrawal response, and nociceptors have been found in aquatic invertebrates such as the sea slug Aplysia. It would seem adaptive to have a warning system that allows animals to avoid life-threatening injury, yet debate does still continue over the capacity for non-mammalian species to experience the discomfort or suffering that is a key component of pain rather than a nociceptive reflex. Contemporary studies over the last 10 years have demonstrated that bony fish possess nociceptors that are similar to those in mammals; that they demonstrate pain-related changes in physiology and behaviour that are reduced by painkillers; that they exhibit higher brain activity when painfully stimulated; and that pain is more important than showing fear or anti-predator behaviour in bony fish. The neurophysiological basis of nociception or pain in fish is demonstrably similar to that in mammals. Pain perception in invertebrates is more controversial as they lack the vertebrate brain, yet recent research evidence confirms that there are behavioural changes in response to potentially painful events. This review will assess the field of pain perception in aquatic species, focusing on fish and selected invertebrate groups to interpret how research findings can inform our understanding of the physiology and evolution of pain. Further, if we accept these animals may be capable of experiencing the negative experience of pain, then the wider implications of human use of these animals should be considered.

  3. Zebrafish as a model for zoonotic aquatic pathogens

    PubMed Central

    Rowe, Hannah M.; Withey, Jeffrey H.; Neely, Melody N.

    2014-01-01

    Aquatic habitats harbor a multitude of bacterial species. Many of these bacteria can act as pathogens to aquatic species and/or non-aquatic organisms, including humans, that come into contact with contaminated water sources or colonized aquatic organisms. In many instances, the bacteria are not pathogenic to the aquatic species they colonize and are only considered pathogens when they come into contact with humans. There is a general lack of knowledge about how the environmental lifestyle of these pathogens allows them to persist, replicate and produce the necessary pathogenic mechanisms to successfully transmit to the human host and cause disease. Recently, the zebrafish infectious disease model has emerged as an ideal system for examining aquatic pathogens, both in the aquatic environment and during infection of the human host. This review will focus on how the zebrafish has been used successfully to analyze the pathogenesis of aquatic bacterial pathogens. PMID:24607289

  4. Monitoring to assess progress toward meeting the Assabet River, Massachusetts, phosphorus total maximum daily load - Aquatic macrophyte biomass and sediment-phosphorus flux

    USGS Publications Warehouse

    Zimmerman, Marc J.; Qian, Yu; Yong Q., Tian

    2011-01-01

    In 2004, the Total Maximum Daily Load (TMDL) for Total Phosphorus in the Assabet River, Massachusetts, was approved by the U.S. Environmental Protection Agency. The goal of the TMDL was to decrease the concentrations of the nutrient phosphorus to mitigate some of the instream ecological effects of eutrophication on the river; these effects were, for the most part, direct consequences of the excessive growth of aquatic macrophytes. The primary instrument effecting lower concentrations of phosphorus was to be strict control of phosphorus releases from four major wastewatertreatment plants in Westborough, Marlborough, Hudson, and Maynard, Massachusetts. The improvements to be achieved from implementing this control were lower concentrations of total and dissolved phosphorus in the river, a 50-percent reduction in aquatic-plant biomass, a 30-percent reduction in episodes of dissolved oxygen supersaturation, no low-flow dissolved oxygen concentrations less than 5.0 milligrams per liter, and a 90-percent reduction in sediment releases of phosphorus to the overlying water. In 2007, the U.S. Geological Survey, in cooperation with the Massachusetts Department of Environmental Protection, initiated studies to evaluate conditions in the Assabet River prior to the upgrading of wastewater-treatment plants to remove more phosphorus from their effluents. The studies, completed in 2008, implemented a visual monitoring plan to evaluate the extent and biomass of the floating macrophyte Lemna minor (commonly known as lesser duckweed) in five impoundments and evaluated the potential for phosphorus flux from sediments in impounded and free-flowing reaches of the river. Hydrologically, the two study years 2007 and 2008 were quite different. In 2007, summer streamflows, although low, were higher than average, and in 2008, the flows were generally higher than in 2007. Visually, the effects of these streamflow differences on the distribution of Lemna were obvious. In 2007, large amounts of

  5. Aquatic toxicity information on VAX VMS backup (ACQUIRE for VMS). Data file

    SciTech Connect

    Not Available

    1991-09-01

    The purpose of Acquire is to provide scientists and managers quick access to a comprehensive, systematic, computerized compilation of aquatic toxicity data. Scientific papers published both nationally and internationally on the toxicity of chemicals to aquatic organisms and plants are collected and reviewed for ACQUIRE. Independently compiled data files that meet ACQUIRE parameter and quality assurance criteria are also included. Selected toxicity test results and related testing information for any individual chemical from laboratory and field aquatic toxicity effects are included for tests with freshwater and marine organisms. The total number of data records in ACQUIRE is now over 105,300. This includes data from 6000 references, for 5200 chemicals and 2400 test species. A major data file, Acute Toxicity of Organic Chemicals (ATOC), has been incorporated into ACQUIRE. The ATOC file contains laboratory acute test data on 525 organic chemicals using juvenile fathead minnows.

  6. The aquatic ecotoxicology of triazine herbicides

    SciTech Connect

    Giddings, J.M.

    1996-10-01

    Triazine herbicides control plant growth by inhibiting photophosphorylation, but typically do not cause permanent cell damage or death. Effects on aquatic plants are reversible; photosynthesis resumes when the herbicide disappears from the water, and sometimes even while it is still present. Effects on aquatic plant communities are further ameliorated by species replacements, so the communities as a whole are less sensitive than their most sensitive species. Atrazine, a representative triazine herbicide, is toxic to aquatic plants (algae and macrophytes) at concentrations in the range of 20 to 200 {mu}g/L or less. Aquatic invertebrates and fish are much less sensitive than plants, with acute toxicity occurring at 1000 {mu}g/L or higher. Ecologically significant effects in aquatic ecosystems are likely only if plant communities are severely damaged by prolonged exposure to high atrazine concentrations.

  7. Aquatic risk assessment of pesticides in Latin America.

    PubMed

    Carriquiriborde, Pedro; Mirabella, Paula; Waichman, Andrea; Solomon, Keith; Van den Brink, Paul J; Maund, Steve

    2014-10-01

    Latin America is anticipated to be a major growth market for agriculture and production is increasing with use of technologies such as pesticides. Reports of contamination of aquatic ecosystems by pesticides in Latin America have raised concerns about potential for adverse ecological effects. In the registration process of pesticides, all countries require significant data packages on aquatic toxicology and environmental fate. However, there are usually no specific requirements to conduct an aquatic risk assessment. To address this issue, the Society of Environmental Toxicology and Chemistry organized a workshop that brought together scientists from academia, government, and industry to review and elaborate on aquatic risk assessment frameworks that can be implemented into regulation of pesticides in Latin America. The workshop concluded that the international framework for risk assessments (protection goals, effects, and exposure assessments, risk characterization, and risk mitigation) is broadly applicable in Latin America but needs further refinement for the use in the region. Some of the challenges associated with these refinements are discussed in the article. It was recognized that there is potential for data sharing both within and outside of the region where conditions are similar. However, there is a need for research to compare local species and environmental conditions to those in other jurisdictions to be able to evaluate the applicability of data used in other countries. Development should also focus on human resources as there is a need to build local capacity and capability, and scientific collaboration and exchange between stakeholders in industry, government, and academia is also important. The meeting also emphasized that, although establishing a regionally relevant risk assessment framework is important, this also needs to be accompanied by enforcement of developed regulations and good management practices to help protect aquatic habitats

  8. When species' ranges meet: assessing differences in habitat selection between sympatric large carnivores.

    PubMed

    Rauset, Geir Rune; Mattisson, Jenny; Andrén, Henrik; Chapron, Guillaume; Persson, Jens

    2013-07-01

    Differentiation in habitat selection among sympatric species may depend on niche partitioning, species interactions, selection mechanisms and scales considered. In a mountainous area in Sweden, we explored hierarchical habitat selection in Global Positioning System-collared individuals of two sympatric large carnivore species; an obligate predator, the Eurasian lynx (Lynx lynx), and a generalist predator and scavenger, the wolverine (Gulo gulo). Although the species' fundamental niches differ widely, their ranges overlap in this area where they share a prey base and main cause of mortality. Both lynx and wolverines selected for steep and rugged terrain in mountainous birch forest and in heaths independent of scale and available habitats. However, the selection of lynx for their preferred habitats was stronger when they were forming home ranges and they selected the same habitats within their home ranges independent of home range composition. Wolverines displayed a greater variability when selecting home ranges and habitat selection also varied with home range composition. Both species selected for habitats that promote survival through limited encounters with humans, but which also are rich in prey, and selection for these habitats was accordingly stronger in winter when human activity was high and prey density was low. We suggest that the observed differences between the species result primarily from different foraging strategies, but may also depend on differences in ranging and resting behaviour, home range size, and relative density of each species. Our results support the prediction that sympatric carnivores with otherwise diverging niches can select for the same resources when sharing main sources of food and mortality.

  9. Large predatory coral trout species unlikely to meet increasing energetic demands in a warming ocean.

    PubMed

    Johansen, J L; Pratchett, M S; Messmer, V; Coker, D J; Tobin, A J; Hoey, A S

    2015-09-08

    Increased ocean temperature due to climate change is raising metabolic demands and energy requirements of marine ectotherms. If productivity of marine systems and fisheries are to persist, individual species must compensate for this demand through increasing energy acquisition or decreasing energy expenditure. Here we reveal that the most important coral reef fishery species in the Indo-west Pacific, the large predatory coral trout Plectropomus leopardus (Serranidae), can behaviourally adjust food intake to maintain body-condition under elevated temperatures, and acclimate over time to consume larger meals. However, these increased energetic demands are unlikely to be met by adequate production at lower trophic levels, as smaller prey species are often the first to decline in response to climate-induced loss of live coral and structural complexity. Consequently, ubiquitous increases in energy consumption due to climate change will increase top-down competition for a dwindling biomass of prey, potentially distorting entire food webs and associated fisheries.

  10. Large predatory coral trout species unlikely to meet increasing energetic demands in a warming ocean

    PubMed Central

    Johansen, J.L.; Pratchett, M.S.; Messmer, V.; Coker, D.J.; Tobin, A.J.; Hoey, A.S.

    2015-01-01

    Increased ocean temperature due to climate change is raising metabolic demands and energy requirements of marine ectotherms. If productivity of marine systems and fisheries are to persist, individual species must compensate for this demand through increasing energy acquisition or decreasing energy expenditure. Here we reveal that the most important coral reef fishery species in the Indo-west Pacific, the large predatory coral trout Plectropomus leopardus (Serranidae), can behaviourally adjust food intake to maintain body-condition under elevated temperatures, and acclimate over time to consume larger meals. However, these increased energetic demands are unlikely to be met by adequate production at lower trophic levels, as smaller prey species are often the first to decline in response to climate-induced loss of live coral and structural complexity. Consequently, ubiquitous increases in energy consumption due to climate change will increase top-down competition for a dwindling biomass of prey, potentially distorting entire food webs and associated fisheries. PMID:26345733

  11. Large predatory coral trout species unlikely to meet increasing energetic demands in a warming ocean.

    PubMed

    Johansen, J L; Pratchett, M S; Messmer, V; Coker, D J; Tobin, A J; Hoey, A S

    2015-01-01

    Increased ocean temperature due to climate change is raising metabolic demands and energy requirements of marine ectotherms. If productivity of marine systems and fisheries are to persist, individual species must compensate for this demand through increasing energy acquisition or decreasing energy expenditure. Here we reveal that the most important coral reef fishery species in the Indo-west Pacific, the large predatory coral trout Plectropomus leopardus (Serranidae), can behaviourally adjust food intake to maintain body-condition under elevated temperatures, and acclimate over time to consume larger meals. However, these increased energetic demands are unlikely to be met by adequate production at lower trophic levels, as smaller prey species are often the first to decline in response to climate-induced loss of live coral and structural complexity. Consequently, ubiquitous increases in energy consumption due to climate change will increase top-down competition for a dwindling biomass of prey, potentially distorting entire food webs and associated fisheries. PMID:26345733

  12. Resource Assessment for Microalgal/Emergent Aquatic Biomass Systems in the Arid Southwest: Final Report

    SciTech Connect

    Vigon, B. W.; Arthur, M. F.; Taft, L. G.; Wagner, C. K.; Lipinsky, E. S.; Litchfield, J. H.; McCandlish, C. D.; Clark, R.

    1982-12-23

    This research project has been designed to facilitate the eventual selection of biomass production systems using aquatic species (microalgal and emergent aquatic plant species (MEAP) which effectively exploit the potentially available resources of the Southwest.

  13. Evaluation of invasions and declines of submersed aquatic macrophytes

    USGS Publications Warehouse

    Chambers, P.A.; Barko, J.W.; Smith, C.S.

    1993-01-01

    During the past 60 yr, sightings of aquatic macrophyte species in geographic regions where they had previously not been found have occurred with increasing frequency, apparently due to both greater dispersal of the plants as a result of human activities as well as better documentation of plant distribution. Intercontinental invasions, such as Myriophyllum spicatum and Hydrilla into North America, Elodea canadensis into Europe and Elodea nuttallii, Egeria densa and Cabomba caroliniana into Japan, have generally been well documented. However, the spread of an exotic species across a continent after its initial introduction (e.g., Potamogeton crispus in North America) or the expansion of a species native to a continent into hitherto unexploited territory (e.g.,the expansion of the North American native Myriophyllum heterophyllum into New England) have received little attention. Natural declines in aquatic macrophyte communities have also received little scientific study although there are many accounts of macrophyte declines. The best-documented example comes from the marine literature where extensive declines of eelgrass (Zostera) occurred in the 1930s along the Atlantic coast due to a pathogenic marine slime mold (''wasting disease''). The aim of this workshop was to identify examples of invasions or natural declines of aquatic macrophyte species throughout the world and assess the importance of environmental factors in their control. Forty-five scientists and aquatic plant managers from ten countries participated in the workshop. Eleven of the participants contributed written evaluations of species invasions and declines in their geo-graphic region. These were distributed to registered participants prior to the meeting and served as the starting-point of workshop discussions. To address the topics raised in the working papers, the participants divided into four working groups to evaluate: 1. Environmental controls of species invasions. 2. Biotic controls of species

  14. 77 FR 34025 - Atlantic Highly Migratory Species; Notice of Public Scoping Meetings

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-06-08

    ... help NMFS determine if existing measures are the best means of achieving certain management objectives... inclusion in a proposed Amendment, and solicited public comment on the objectives and management options... Species Fishery Management Plan, which will focus on management issues related to Atlantic bluefin tuna....

  15. More Cercospora Species Infect Soybeans across the Americas than Meets the Eye.

    PubMed

    Soares, Ana Paula Gomes; Guillin, Eduardo A; Borges, Leandro Luiz; Silva, Amanda C T da; Almeida, Álvaro M R de; Grijalba, Pablo E; Gottlieb, Alexandra M; Bluhm, Burton H; Oliveira, Luiz Orlando de

    2015-01-01

    Diseases of soybean caused by Cercospora spp. are endemic throughout the world's soybean production regions. Species diversity in the genus Cercospora has been underestimated due to overdependence on morphological characteristics, symptoms, and host associations. Currently, only two species (Cercospora kikuchii and C. sojina) are recognized to infect soybean; C. kikuchii causes Cercospora leaf blight (CLB) and purple seed stain (PSS), whereas C. sojina causes frogeye leaf spot. To assess cryptic speciation among pathogens causing CLB and PSS, phylogenetic and phylogeographic analyses were performed with isolates from the top three soybean producing countries (USA, Brazil, and Argentina; collectively accounting for ~80% of global production). Eight nuclear genes and one mitochondrial gene were partially sequenced and analyzed. Additionally, amino acid substitutions conferring fungicide resistance were surveyed, and the production of cercosporin (a polyketide toxin produced by many Cercospora spp.) was assessed. From these analyses, the long-held assumption of C. kikuchii as the single causal agent of CLB and PSS was rejected experimentally. Four cercosporin-producing lineages were uncovered with origins (about 1 Mya) predicted to predate agriculture. Some of the Cercospora spp. newly associated with CLB and PSS appear to represent undescribed species; others were not previously reported to infect soybeans. Lineage 1, which contained the ex-type strain of C. kikuchii, was monophyletic and occurred in Argentina and Brazil. In contrast, lineages 2 and 3 were polyphyletic and contained wide-host range species complexes. Lineage 4 was monophyletic, thrived in Argentina and the USA, and included the generalist Cercospora cf. flagellaris. Interlineage recombination was detected, along with a high frequency of mutations linked to fungicide resistance in lineages 2 and 3. These findings point to cryptic Cercospora species as underappreciated global considerations for soybean

  16. More Cercospora Species Infect Soybeans across the Americas than Meets the Eye

    PubMed Central

    Soares, Ana Paula Gomes; Guillin, Eduardo A.; Borges, Leandro Luiz; da Silva, Amanda C. T.; de Almeida, Álvaro M. R.; Grijalba, Pablo E.; Gottlieb, Alexandra M.; Bluhm, Burton H.; de Oliveira, Luiz Orlando

    2015-01-01

    Diseases of soybean caused by Cercospora spp. are endemic throughout the world’s soybean production regions. Species diversity in the genus Cercospora has been underestimated due to overdependence on morphological characteristics, symptoms, and host associations. Currently, only two species (Cercospora kikuchii and C. sojina) are recognized to infect soybean; C. kikuchii causes Cercospora leaf blight (CLB) and purple seed stain (PSS), whereas C. sojina causes frogeye leaf spot. To assess cryptic speciation among pathogens causing CLB and PSS, phylogenetic and phylogeographic analyses were performed with isolates from the top three soybean producing countries (USA, Brazil, and Argentina; collectively accounting for ~80% of global production). Eight nuclear genes and one mitochondrial gene were partially sequenced and analyzed. Additionally, amino acid substitutions conferring fungicide resistance were surveyed, and the production of cercosporin (a polyketide toxin produced by many Cercospora spp.) was assessed. From these analyses, the long-held assumption of C. kikuchii as the single causal agent of CLB and PSS was rejected experimentally. Four cercosporin-producing lineages were uncovered with origins (about 1 Mya) predicted to predate agriculture. Some of the Cercospora spp. newly associated with CLB and PSS appear to represent undescribed species; others were not previously reported to infect soybeans. Lineage 1, which contained the ex-type strain of C. kikuchii, was monophyletic and occurred in Argentina and Brazil. In contrast, lineages 2 and 3 were polyphyletic and contained wide-host range species complexes. Lineage 4 was monophyletic, thrived in Argentina and the USA, and included the generalist Cercospora cf. flagellaris. Interlineage recombination was detected, along with a high frequency of mutations linked to fungicide resistance in lineages 2 and 3. These findings point to cryptic Cercospora species as underappreciated global considerations for

  17. Proximate nutrient analyses of four species of submerged aquatic vegetation consumed by Florida manatee (Trichechus manatus latirostris) compared to romaine lettuce (Lactuca sativa var. longifolia).

    PubMed

    Siegal-Willott, Jessica L; Harr, Kendal; Hayek, Lee-Ann C; Scott, Karen C; Gerlach, Trevor; Sirois, Paul; Reuter, Mike; Crewz, David W; Hill, Richard C

    2010-12-01

    Free-ranging Florida manatees (Trichechus manatus latirostris) consume a variety of sea grasses and algae. This study compared the dry matter (DM) content, proximate nutrients (crude protein [CP], ether-extracted crude fat [EE], nonfiber carbohydrate [NFC], and ash), and the calculated digestible energy (DE) of sea grasses (Thalassia testudinum, Halodule wrightii, and Syringodium filiforme) collected in spring, summer, and winter, and an alga (Chara sp.) with those of romaine lettuce (Lactuca sativa var. longifolia). Neutral-detergent fiber (NDF), acid-detergent fiber (ADF), and lignin (L) measured after ash-extraction were also compared. Results of statistical tests (C = 0.01) revealed DM content was higher in aquatic vegetation than in lettuce (P = 0.0001), but NDF and ADF were up to threefold greater, EE (P = 0.00001) and CP (P = 0.00001) were 2-9 times less, and NFC (P = 0.0001) was 2-6 times lower in sea grass than in lettuce, on a DM basis. Chara was lower in NDF, ADF, L, EE, CP, and NFC relative to lettuce on a DM basis. Ash content (DM basis) was higher (P = 0.0001), and DE was 2-6 times lower in aquatic vegetation than in lettuce. Sea grass rhizomes had lower L and higher ash contents (DM basis) than sea grass leaves. Based on the nutrient analyses, romaine lettuce and sea grasses are not equivalent forages, which suggests that the current diet of captive Florida manatees should be reassessed.

  18. Proximate nutrient analyses of four species of submerged aquatic vegetation consumed by Florida manatee (Trichechus manatus latirostris) compared to romaine lettuce (Lactuca sativa var. longifolia).

    PubMed

    Siegal-Willott, Jessica L; Harr, Kendal; Hayek, Lee-Ann C; Scott, Karen C; Gerlach, Trevor; Sirois, Paul; Reuter, Mike; Crewz, David W; Hill, Richard C

    2010-12-01

    Free-ranging Florida manatees (Trichechus manatus latirostris) consume a variety of sea grasses and algae. This study compared the dry matter (DM) content, proximate nutrients (crude protein [CP], ether-extracted crude fat [EE], nonfiber carbohydrate [NFC], and ash), and the calculated digestible energy (DE) of sea grasses (Thalassia testudinum, Halodule wrightii, and Syringodium filiforme) collected in spring, summer, and winter, and an alga (Chara sp.) with those of romaine lettuce (Lactuca sativa var. longifolia). Neutral-detergent fiber (NDF), acid-detergent fiber (ADF), and lignin (L) measured after ash-extraction were also compared. Results of statistical tests (C = 0.01) revealed DM content was higher in aquatic vegetation than in lettuce (P = 0.0001), but NDF and ADF were up to threefold greater, EE (P = 0.00001) and CP (P = 0.00001) were 2-9 times less, and NFC (P = 0.0001) was 2-6 times lower in sea grass than in lettuce, on a DM basis. Chara was lower in NDF, ADF, L, EE, CP, and NFC relative to lettuce on a DM basis. Ash content (DM basis) was higher (P = 0.0001), and DE was 2-6 times lower in aquatic vegetation than in lettuce. Sea grass rhizomes had lower L and higher ash contents (DM basis) than sea grass leaves. Based on the nutrient analyses, romaine lettuce and sea grasses are not equivalent forages, which suggests that the current diet of captive Florida manatees should be reassessed. PMID:21370638

  19. Aquatic Therapy for Children

    ERIC Educational Resources Information Center

    Kucher, Greta; Moore, Kelsey; Rodia, Rachel; Moser, Christy Szczech

    2015-01-01

    Aquatic therapy has long been highlighted in the literature as a potentially powerful therapeutic intervention. This review will highlight basic definitions of aquatic therapy, review salient research, and identify specific diagnoses that may benefit from aquatic therapy. Online resources, blogs, and books that occupational therapists may find…

  20. Experiences of countries with new aquatic industries: the development of aquaculture in Iran.

    PubMed

    Rajaby, M

    2008-04-01

    Although caviar is the most significant and famous fishery product of Iran, in recent years the country has gained a lot of experience and had some significant success with other fishery and aquaculture products. Iranian fisheries and aquaculture production reached 522,000 metric tons in 2005, of which 75% originated from capture fishery and 25% from aquaculture activities. Various fishery and aquaculture activities take place in Iran to help meet domestic demand for aquaculture products and to maintain the existing level of natural resources in seas and rivers (restocking natural sources). The ways in which Iran has been able to make progress in developing aquaculture--which could serve as a model for other countries in the region and for developing countries--are as follows: a) optimising the use of climatic diversity in raising various aquatic species; b) establishing the required governmental and nongovernmental organisations for raising aquatic animals, and planning and creating appropriate relationships between those organisations and entities; c) training skilful manpower and educating specialists in the field of aquatic animal health and diseases; d) increasing per capita consumption of fishery products through sensitising public opinion; and e) meeting the requirements for raising the rate of aquatic animal culture and developing the export of fishery products, i.e. by supplying eyed eggs, feed, broodstock, etc.

  1. Morbillivirus infections in aquatic mammals.

    PubMed

    Visser, I K; van Bressem, M F; Barrett, T; Osterhaus, A D

    1993-01-01

    Infections with morbilliviruses have caused heavy losses among different populations of aquatic mammals during the last 5 years. Two different morbilliviruses were isolated from disease outbreaks among seals in Europe and Siberia: phocid distemper virus-1 (PDV-1) and phocid distemper virus-2 (PDV-2) respectively. PDV-1 was characterized as a newly identified morbillivirus, most related to canine distemper virus (CDV), whereas PDV-2 most probably is a strain of CDV. Morbilliviruses were also isolated from porpoises--porpoise morbillivirus (PMV)--and dolphins--dolphin morbillivirus (DMV)--which had stranded on the coasts of Europe. PMV and DMV proved to be closely related to, but distinct from 2 ruminant morbilliviruses, rinderpest virus (RPV) and peste-des-petits-ruminants virus (PPRV). Serological surveys carried out among pinniped and cetacean species in the seas of Europe and North America indicated that infections with these newly discovered morbilliviruses or closely related viruses commonly occur among aquatic mammal species. PMID:8343804

  2. Quantifying aquatic invasion patterns through space and time

    EPA Science Inventory

    The objective of my study was to quantify the apparent spatio-temporal relationship between anthropogenic introduction pathway intensity and non-native aquatic species presence throughout the Laurentian Great Lakes. Non-native aquatic species early detection programs are based pr...

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

    PubMed

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

    2011-10-01

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

  4. [Influence of two different species of aquatic plant communities on the concentration of various nitrogen forms in sediment of Lake Taihu].

    PubMed

    Ma, Jiu-Yuan; Wang, Guo-Xiang; Li, Zhen-Guo; Xu, Kuan; Zhou, Feng; Zhang, Jia

    2013-11-01

    To investigate the spatial distribution of nitrogen in the sediment from both internal and external sites of Potamogeton malaianus and Limnanthemun nymphoides communities, levels of various forms of nitrogen were quantified in sediment samples collected from Gonghu Bay, the southern region and the intermediate area between East and West mountains of Lake Taihu in June 2012. The results showed that: (1) Within the algae-type region in Gonghu Bay, the contents of organic (Org-N) and total nitrogen (TN) in the internal sediment (0-25 cm) from P. malaianus communities were higher than those of the external sediment, by 38.06% and 25.65%, respectively. (2) In the non-algal region, the contents of TN, Org-N, NH4(+)-N and NO3(-) -N in the internal sediments from P. malaianus communities were lower by 43.29%, 50.78%, 7.09% and 10.86% compared to those in the external sediments; for L. nymphoides communities, the contents of TN, Org-N, NH4(+) -N and NO3(-) -N in the external sediments were lower by 4.65%, 4.63%, 5.01% and 2.76% compared to the internal sediments. These values suggested that the promotion in reducing sedimentary nitrogen was more effective by the P. malaianus community than by the L. nymphoides community. (3) A significant positive correlation (P < 0.05, n = 24) was found between pH and TN within the external sediments and between pH and NO3(-) -N within the internal sediments (P < 0.05, n = 24), while a significant negative correlation (P < 0.05, n = 24) was found between pH and NH4(+)-N of both aquatic plant communities. The redox potential (Eh) was also found to be significantly positively correlated with TN in both the internal and external sediments of P. malaianus communities (GMN, P < 0.01, R = 0.922 8 * *; NMN, P < 0.01, R = 0.827 7 * *; GMW, P < 0.05, R = 0.748 9 *; NMW, P < 0.05, R = 0.663 7 *). It is therefore concluded that the presence of aquatic plant communities could impact the physical and chemical properties of the sediments.

  5. The spread of pathogens through trade in aquatic animals and their products.

    PubMed

    Rodgers, C J; Mohan, C V; Peeler, E J

    2011-04-01

    It is well known that the transboundary spread of infectious diseases is aided by trade in live animals and the consequences can be severe if, as a result, a pathogen broadens its host range to new species. Trade in aquatic animal species is increasing, and aquaculture is also expanding to meet the growing human population's demands for animal protein. Moreover, it is clear that aquaculture has created potential new pathways by which pathogens and diseases may be introduced or spread to new areas. The risk of pathogen transfer is generally considered greater for the movement of live aquatic animals than for the movement of processed and dead products. The currently available health standards support the concept of minimising the risk of disease and pathogen incursion while, at the same time, avoiding unjustifiable or unnecessary impediments to trade. Nevertheless, the international spread of diseases through the movement of animals still occurs, despite these standards. Consequently, this paper considers the evidence linking international trade in aquatic animals and aquatic animal-derived products with the transmission and spread of diseases. The authors provide examples of pathogen transfer leading to disease spread and considerthe situation of emerging diseases, as well as the need for a holistic approach to deal with risk-based threats at their source.

  6. An evaluation of the relations between flow regime components, stream characteristics, species traits and meta-demographic rates of warmwater stream fishes: Implications for aquatic resource management

    USGS Publications Warehouse

    Peterson, James T.; Shea, C.P.

    2015-01-01

    Fishery biologists are increasingly recognizing the importance of considering the dynamic nature of streams when developing streamflow policies. Such approaches require information on how flow regimes influence the physical environment and how those factors, in turn, affect species-specific demographic rates. A more cost-effective alternative could be the use of dynamic occupancy models to predict how species are likely to respond to changes in flow. To appraise the efficacy of this approach, we evaluated relative support for hypothesized effects of seasonal streamflow components, stream channel characteristics, and fish species traits on local extinction, colonization, and recruitment (meta-demographic rates) of stream fishes. We used 4 years of seasonal fish collection data from 23 streams to fit multistate, multiseason occupancy models for 42 fish species in the lower Flint River Basin, Georgia. Modelling results suggested that meta-demographic rates were influenced by streamflows, particularly short-term (10-day) flows. Flow effects on meta-demographic rates also varied with stream size, channel morphology, and fish species traits. Small-bodied species with generalized life-history characteristics were more resilient to flow variability than large-bodied species with specialized life-history characteristics. Using this approach, we simplified the modelling framework, thereby facilitating the development of dynamic, spatially explicit evaluations of the ecological consequences of water resource development activities over broad geographic areas. Published 2014. This article is a U.S. Government work and is in the public domain in the USA.

  7. NEW APPROACHES TO ESTIMATING INDIRECT PHOTOLYSIS RATES IN AQUATIC ENVIRONMENTS

    EPA Science Inventory

    Indirect photoreactions in aquatic environments are driven by reactive species, most of which are oxygen centered. Humic substances play an important role in photosensitizing the production of these reactive species, which include singlet molecular oxygen, superoxide ions, hydrog...

  8. Hydraena (Hydraenopsis) ateneo, new species (Coleoptera, Hydraenidae) and other aquatic Polyphaga from a small habitat patch in a highly urbanized landscape of Metro Manila, Philippines

    PubMed Central

    Freitag, Hendrik

    2013-01-01

    Abstract Seven species of Hydraenidae, Hydrophilidae and Elmidae are recorded from temporary freshwater habitats at the Ateneo de Manila University Campus in the metropolitan area of Manila, Philippines. They were identified as Enochrus (Lumetus) fragiloides d’Orchymont, Helochares (Hydrobaticus) lepidus d’Orchymont, Helochares (Helochares) pallens (MacLeay), Hydraena (Hydraenopsis) scabra d’Orchymont, Hydraena (Hydraenopsis) palawanensis Freitag & Jäch (new record for Luzon Island), Stenelmis sp. A further hydraenid species was unknown to science and is newly described: Hydraena (Hydraenopsis) ateneo Freitag, sp. n. Aedeagus, gonocoxite, spermatheca, and female tergite X are illustrated by computer-based line drawings. Habitus images of all three Hydraena Kugelann species recorded and a checklist of the Philippine Hydraena are provided. The presence of these seven species in the Ateneo campus is briefly discussed in regard to the area’s history. Measures to maintain and extend semi-natural islands of biodiversity in urban areas are suggested. PMID:24146550

  9. Colonization pattern of aquatic hyphomycetes on leaf packs in subtropical stream.

    PubMed

    Abdel-Raheem, A M

    1997-01-01

    Steralized leaf pieces of eight plants (Eucalyptus rostrata, Phoenix dactylifera, Phragmites australis, Musa nana, Salix subserrata, Cyperus alopecuroides, Ricinus communis and Eichhornia crassipes) were submerged in the Nile stream. Thirty-nine species of aquatic hyphomycetes were colonized on the plant leaves. Eucalyptus was the best substratum (30 species) for colonization by aquatic hyphomycetes. Phoenix (14 species), Phragmites (11 species), Salix (9 species), Musa (8 species), Ricinus and Cyperus (6 species) were also good substrata for aquatic hyphomycetes colonization. Echhornia (aquatic plant) was not suitable for aquatic hyphomycetes colonization. Alatospora acuminata, Triscelophorus monosporus and Tetracladium marchalianum were found to be the major colonizers on all leaf materials. Temperature and dissolved oxygen were the highest physico-chemical parameters affecting the aquatic hyphomycetes colonization. These results indicate that aquatic hyphomycetes have been shown to be successful colonizers on plants leaf in river Nile in Egypt as subtropical region.

  10. Apply Pesticides Correctly, A Guide for Commercial Applicators: Aquatic Pest Control.

    ERIC Educational Resources Information Center

    Wamsley, Mary Ann, Ed.; Vermeire, Donna M., Ed.

    This guide presents information needed to meet the requirements for pesticide applicator certification. The first part deals with recognition and control of aquatic pests such as aquatic weeds, fish and other vertebrates. Environmental concerns in aquatic pest control are discussed in the second section. (CS)

  11. The "Marinated" Classroom. A Sourcebook of Aquatic Activities for the Elementary Classroom.

    ERIC Educational Resources Information Center

    Rakow, Steven J.

    This handbook is designed to meet the aquatic education needs of Minnesota elementary teachers and students (aquatic education referring to the study of freshwater systems). The handbook is divided into three parts. Part 1 (an introduction) provides an overview of aquatic education, a description of the use of the handbook, and two indexes to…

  12. The "Marinated" Classroom. A Sourcebook of Aquatic Activities for the Secondary Classroom.

    ERIC Educational Resources Information Center

    Rakow, Steven J.

    This handbook is designed to meet the aquatic education needs of Minnesota secondary teachers and students (aquatic education referring to the study of freshwater systems). The handbook is divided into three parts. Part 1 (an introduction) provides an overview of aquatic education, a description of the use of the handbook, and two indices to…

  13. Safe, Effective Use of Pesticides, A Manual for Commercial Applicators: Aquatic Pest Control.

    ERIC Educational Resources Information Center

    Extension Service (USDA), Washington, DC.

    This manual is intended to assist pesticide applicators in the area of aquatic pest control meet the requirements of the Michigan Department of Agriculture for certification. The Environmental Protection Agency (EPA) Aquatic Pest Control Guide served as a basis for this manual. The six sections presented describe: (1) Aquatic pest control; (2)…

  14. Photographing Aquatic Organisms

    ERIC Educational Resources Information Center

    Olsen, Sigurd

    1977-01-01

    Techniques for effective photography of aquatic organisms in the field and laboratory are described. Photography of microscopic organisms and construction techniques of photoaquaria are described. (CS)

  15. Aquatic toxicity of two Corexit dispersants.

    PubMed

    George-Ares, A; Clark, J R

    2000-04-01

    The oil spill dispersants, Corexit 9500 and Corexit 9527 have low to moderate toxicity to most aquatic species in laboratory tests. Toxicity estimates are significantly affected by test variables such as species, lifestage, exposure duration, and temperature. Aquatic toxicity data generated from spiked, declining exposures (107 min half-life) are more reflective of actual dispersant use conditions. Decisions to use oil spill response chemicals should not be based solely on aquatic toxicity. Factors to consider include product effectiveness, toxicity of dispersed oil, species/habitats requiring priority protection, and recovery potential of sensitive habitats and populations. An environmental risk assessment approach is recommended where dispersant toxicity data generated under environmentally relevant exposures are compared to estimated environmental concentrations of dispersants. PMID:10718584

  16. Aquatic toxicity of two Corexit dispersants.

    PubMed

    George-Ares, A; Clark, J R

    2000-04-01

    The oil spill dispersants, Corexit 9500 and Corexit 9527 have low to moderate toxicity to most aquatic species in laboratory tests. Toxicity estimates are significantly affected by test variables such as species, lifestage, exposure duration, and temperature. Aquatic toxicity data generated from spiked, declining exposures (107 min half-life) are more reflective of actual dispersant use conditions. Decisions to use oil spill response chemicals should not be based solely on aquatic toxicity. Factors to consider include product effectiveness, toxicity of dispersed oil, species/habitats requiring priority protection, and recovery potential of sensitive habitats and populations. An environmental risk assessment approach is recommended where dispersant toxicity data generated under environmentally relevant exposures are compared to estimated environmental concentrations of dispersants.

  17. Spatial and Temporal Patterns of Aquatic Habitats in a Karstic Environment: Implications for the Stream Biota From Species to Community Level

    NASA Astrophysics Data System (ADS)

    Meyer, E. I.

    2005-05-01

    Due to the specific geohydrological situation, the investigated drainage network of the Paderborner Hochflaeche (North-Rhine Westphalia, Germany) shows typical karst features like sinkholes, dolines, underground caves, dry valleys, and karst springs. Many streams are characterized by spatial and temporal flow intermittency. The objectives of the study were to elucidate temporal and spatial flow patterns, invertebrate distribution and species-specific adaptations. It was hypothesized that different hydrological stream sections are characterized by different lotic communities. It was further assumed that in temporary stream sections a high proportion of the benthic assemblages consists of species adapted to the harsh abiotic conditions either by strategies of resistance or of resilience. Most of the streams are summerdry, and drought duration increases with increasing distance from the perennial upstream sections. However, depending on the precipitation, sudden flash flows may occur. Particularly in small streams permanent springs and springbrook sections can be observed locally. Lotic communites differ in the different hydraulic habitats, and experiments on the species level give evidence for species-dependent plasticity in life history traits or for behavioural adaptations. It can be concluded that temporary karst streams contribute to regional biodiversity, which might be threatened by management practices.

  18. Nitrous oxide emission by aquatic macrofauna

    PubMed Central

    Stief, Peter; Poulsen, Morten; Nielsen, Lars Peter; Brix, Hans; Schramm, Andreas

    2009-01-01

    A large variety of aquatic animals was found to emit the potent greenhouse gas nitrous oxide when nitrate was present in the environment. The emission was ascribed to denitrification by ingested bacteria in the anoxic animal gut, and the exceptionally high N2O-to-N2 production ratio suggested delayed induction of the last step of denitrification. Filter- and deposit-feeding animal species showed the highest rates of nitrous oxide emission and predators the lowest, probably reflecting the different amounts of denitrifying bacteria in the diet. We estimate that nitrous oxide emission by aquatic animals is quantitatively important in nitrate-rich aquatic environments like freshwater, coastal marine, and deep-sea ecosystems. The contribution of this source to overall nitrous oxide emission from aquatic environments might further increase because of the projected increase of nitrate availability in tropical regions and the numeric dominance of filter- and deposit-feeders in eutrophic ecosystems. PMID:19255427

  19. Passive electroreception in aquatic mammals.

    PubMed

    Czech-Damal, Nicole U; Dehnhardt, Guido; Manger, Paul; Hanke, Wolf

    2013-06-01

    Passive electroreception is a sensory modality in many aquatic vertebrates, predominantly fishes. Using passive electroreception, the animal can detect and analyze electric fields in its environment. Most electric fields in the environment are of biogenic origin, often produced by prey items. These electric fields can be relatively strong and can be a highly valuable source of information for a predator, as underlined by the fact that electroreception has evolved multiple times independently. The only mammals that possess electroreception are the platypus (Ornithorhynchus anatinus) and the echidnas (Tachyglossidae) from the monotreme order, and, recently discovered, the Guiana dolphin (Sotalia guianensis) from the cetacean order. Here we review the morphology, function and origin of the electroreceptors in the two aquatic species, the platypus and the Guiana dolphin. The morphology shows certain similarities, also similar to ampullary electroreceptors in fishes, that provide cues for the search for electroreceptors in more vertebrate and invertebrate species. The function of these organs appears to be very similar. Both species search for prey animals in low-visibility conditions or while digging in the substrate, and sensory thresholds are within one order of magnitude. The electroreceptors in both species are innervated by the trigeminal nerve. The origin of the accessory structures, however, is completely different; electroreceptors in the platypus have developed from skin glands, in the Guiana dolphin, from the vibrissal system. PMID:23187861

  20. 50 CFR 453.05 - Committee meetings.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... OF COMMERCE); ENDANGERED SPECIES COMMITTEE REGULATIONS ENDANGERED SPECIES EXEMPTION PROCESS ENDANGERED SPECIES COMMITTEE § 453.05 Committee meetings. (a) The committee shall meet at the call of...

  1. 50 CFR 453.05 - Committee meetings.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... OF COMMERCE); ENDANGERED SPECIES COMMITTEE REGULATIONS ENDANGERED SPECIES EXEMPTION PROCESS ENDANGERED SPECIES COMMITTEE § 453.05 Committee meetings. (a) The committee shall meet at the call of...

  2. 50 CFR 453.05 - Committee meetings.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... OF COMMERCE); ENDANGERED SPECIES COMMITTEE REGULATIONS ENDANGERED SPECIES EXEMPTION PROCESS ENDANGERED SPECIES COMMITTEE § 453.05 Committee meetings. (a) The committee shall meet at the call of...

  3. 50 CFR 453.05 - Committee meetings.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... OF COMMERCE); ENDANGERED SPECIES COMMITTEE REGULATIONS ENDANGERED SPECIES EXEMPTION PROCESS ENDANGERED SPECIES COMMITTEE § 453.05 Committee meetings. (a) The committee shall meet at the call of...

  4. 50 CFR 453.05 - Committee meetings.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... OF COMMERCE); ENDANGERED SPECIES COMMITTEE REGULATIONS ENDANGERED SPECIES EXEMPTION PROCESS ENDANGERED SPECIES COMMITTEE § 453.05 Committee meetings. (a) The committee shall meet at the call of...

  5. Finfish and aquatic invertebrate pathology resources for now and the future✩

    PubMed Central

    Spitsbergen, Jan M.; Blazer, Vicki S.; Bowser, Paul R.; Cheng, Keith C.; Cooper, Keith R.; Cooper, Timothy K.; Frasca, Salvatore; Groman, David B.; Harper, Claudia M.; (Mac) Law, Jerry M.; Marty, Gary D.; Smolowitz, Roxanna M.; Leger, Judy St.; Wolf, Douglas C.; Wolf, Jeffrey C.

    2009-01-01

    Utilization of finfish and aquatic invertebrates in biomedical research and as environmental sentinels has grown dramatically in recent decades. Likewise the aquaculture of finfish and invertebrates has expanded rapidly worldwide as populations of some aquatic food species and threatened or endangered aquatic species have plummeted due to overharvesting or habitat degradation. This increasing intensive culture and use of aquatic species has heightened the importance of maintaining a sophisticated understanding of pathology of various organ systems of these diverse species. Yet, except for selected species long cultivated in aquaculture, pathology databases and the workforce of highly trained pathologists lag behind those available for most laboratory animals and domestic mammalian and avian species. Several factors must change to maximize the use, understanding, and protection of important aquatic species: 1) improvements in databases of abnormalities across species; 2) standardization of diagnostic criteria for proliferative and nonproliferative lesions; and 3) more uniform and rigorous training in aquatic morphologic pathology. PMID:18948226

  6. Finfish and aquatic invertebrate pathology resources for now and the future.

    PubMed

    Spitsbergen, Jan M; Blazer, Vicki S; Bowser, Paul R; Cheng, Keith C; Cooper, Keith R; Cooper, Timothy K; Frasca, Salvatore; Groman, David B; Harper, Claudia M; Law, Jerry M Mac; Marty, Gary D; Smolowitz, Roxanna M; St Leger, Judy; Wolf, Douglas C; Wolf, Jeffrey C

    2009-03-01

    Utilization of finfish and aquatic invertebrates in biomedical research and as environmental sentinels has grown dramatically in recent decades. Likewise the aquaculture of finfish and invertebrates has expanded rapidly worldwide as populations of some aquatic food species and threatened or endangered aquatic species have plummeted due to overharvesting or habitat degradation. This increasing intensive culture and use of aquatic species has heightened the importance of maintaining a sophisticated understanding of pathology of various organ systems of these diverse species. Yet, except for selected species long cultivated in aquaculture, pathology databases and the workforce of highly trained pathologists lag behind those available for most laboratory animals and domestic mammalian and avian species. Several factors must change to maximize the use, understanding, and protection of important aquatic species: 1) improvements in databases of abnormalities across species; 2) standardization of diagnostic criteria for proliferative and nonproliferative lesions; and 3) more uniform and rigorous training in aquatic morphologic pathology.

  7. Sylphella puccoon gen. n., sp. n. and two additional new species of aquatic oligochaetes (Lumbriculidae, Clitellata) from poorly-known lotic habitats in North Carolina (USA)

    USGS Publications Warehouse

    Rodriguez, Pilar; Fend, Steven V.; Lenat, David R.

    2014-01-01

    Three new species of Lumbriculidae were collected from floodplain seeps and small streams in southeastern North America. Some of these habitats are naturally acidic. Sylphella puccoon gen. n., sp. n. has prosoporous male ducts in X-XI, and spermathecae in XII-XIII. Muscular, spherical atrial ampullae and acuminate penial sheaths distinguish this monotypic new genus from other lumbriculid genera having similar arrangements of reproductive organs. Cookidrilus pocosinus sp. n. resembles its two subterranean, Palearctic congeners in the arrangement of reproductive organs, but is easily distinguished by the position of the spermathecal pores in front of the chaetae in X-XIII. Stylodrilus coreyi sp. n. differs from congeners having simple-pointed chaetae and elongate atria primarily by the structure of the male duct and the large clusters of prostate cells. Streams and wetlands of Southeastern USA have a remarkably high diversity of endemic lumbriculids, and these poorly-known invertebrates should be considered in conservation efforts.

  8. Sylphella puccoon gen. n., sp. n. and two additional new species of aquatic oligochaetes (Lumbriculidae, Clitellata) from poorly-known lotic habitats in North Carolina (USA)

    PubMed Central

    Rodriguez, Pilar; Fend, Steven V.; Lenat, David R.

    2014-01-01

    Abstract Three new species of Lumbriculidae were collected from floodplain seeps and small streams in southeastern North America. Some of these habitats are naturally acidic. Sylphella puccoon gen. n., sp. n. has prosoporous male ducts in X–XI, and spermathecae in XII–XIII. Muscular, spherical atrial ampullae and acuminate penial sheaths distinguish this monotypic new genus from other lumbriculid genera having similar arrangements of reproductive organs. Cookidrilus pocosinus sp. n. resembles its two subterranean, Palearctic congeners in the arrangement of reproductive organs, but is easily distinguished by the position of the spermathecal pores in front of the chaetae in X–XIII. Stylodrilus coreyi sp. n. differs from congeners having simple-pointed chaetae and elongate atria primarily by the structure of the male duct and the large clusters of prostate cells. Streams and wetlands of Southeastern USA have a remarkably high diversity of endemic lumbriculids, and these poorly-known invertebrates should be considered in conservation efforts. PMID:25493045

  9. Marine envenomations and aquatic dermatology.

    PubMed

    Soppe, G G

    1989-08-01

    Jellyfish stings are usually mild except those caused by species in the South Pacific. The box jellyfish can produce a severe cardiorespiratory insult. The sting of the Portuguese man-of-war is more potent than that of the common jellyfish. The Indo-Pacific area is the source of the most venomous bony fish. Many injuries can be avoided by wearing shoes when walking in shallow water or tide pools. Aquatic-related skin infections may involve unusual organisms. Swimmer's itch, a disease of freshwater bathing, is caused by cercariae. Seabather's eruption produces a rash in swimsuit-covered areas; the etiology is not clear. PMID:2569260

  10. Population approaches to aquatic toxicology

    SciTech Connect

    Vinegar, M.B.

    1981-10-01

    Field studies in which age-specific survivorship and fecundity are measured can provide data for the validation of laboratory studies conducted to assess the effects of toxic materials on aquatic species. Comparison of the variability of age-specific survivorship and fecundity in polluted versus nonpolluted areas would provide insight into the consequences of pollution at the population level. Techniques which permit prediction of population structure and growth from age-specific survivorship and fecundity schedules are described. These techniques include the life table and the Leslie matrix. Examples of population studies in which these techniques may be applied are given.

  11. Aquatic arsenic: phytoremediation using floating macrophytes.

    PubMed

    Rahman, M Azizur; Hasegawa, H

    2011-04-01

    Phytoremediation, a plant based green technology, has received increasing attention after the discovery of hyperaccumulating plants which are able to accumulate, translocate, and concentrate high amount of certain toxic elements in their above-ground/harvestable parts. Phytoremediation includes several processes namely, phytoextraction, phytodegradation, rhizofiltration, phytostabilization and phytovolatilization. Both terrestrial and aquatic plants have been tested to remediate contaminated soils and waters, respectively. A number of aquatic plant species have been investigated for the remediation of toxic contaminants such as As, Zn, Cd, Cu, Pb, Cr, Hg, etc. Arsenic, one of the deadly toxic elements, is widely distributed in the aquatic systems as a result of mineral dissolution from volcanic or sedimentary rocks as well as from the dilution of geothermal waters. In addition, the agricultural and industrial effluent discharges are also considered for arsenic contamination in natural waters. Some aquatic plants have been reported to accumulate high level of arsenic from contaminated water. Water hyacinth (Eichhornia crassipes), duckweeds (Lemna gibba, Lemna minor, Spirodela polyrhiza), water spinach (Ipomoea aquatica), water ferns (Azolla caroliniana, Azolla filiculoides, and Azolla pinnata), water cabbage (Pistia stratiotes), hydrilla (Hydrilla verticillata) and watercress (Lepidium sativum) have been studied to investigate their arsenic uptake ability and mechanisms, and to evaluate their potential in phytoremediation technology. It has been suggested that the aquatic macrophytes would be potential for arsenic phytoremediation, and this paper reviews up to date knowledge on arsenic phytoremediation by common aquatic macrophytes. PMID:21435676

  12. Aquatic arsenic: phytoremediation using floating macrophytes.

    PubMed

    Rahman, M Azizur; Hasegawa, H

    2011-04-01

    Phytoremediation, a plant based green technology, has received increasing attention after the discovery of hyperaccumulating plants which are able to accumulate, translocate, and concentrate high amount of certain toxic elements in their above-ground/harvestable parts. Phytoremediation includes several processes namely, phytoextraction, phytodegradation, rhizofiltration, phytostabilization and phytovolatilization. Both terrestrial and aquatic plants have been tested to remediate contaminated soils and waters, respectively. A number of aquatic plant species have been investigated for the remediation of toxic contaminants such as As, Zn, Cd, Cu, Pb, Cr, Hg, etc. Arsenic, one of the deadly toxic elements, is widely distributed in the aquatic systems as a result of mineral dissolution from volcanic or sedimentary rocks as well as from the dilution of geothermal waters. In addition, the agricultural and industrial effluent discharges are also considered for arsenic contamination in natural waters. Some aquatic plants have been reported to accumulate high level of arsenic from contaminated water. Water hyacinth (Eichhornia crassipes), duckweeds (Lemna gibba, Lemna minor, Spirodela polyrhiza), water spinach (Ipomoea aquatica), water ferns (Azolla caroliniana, Azolla filiculoides, and Azolla pinnata), water cabbage (Pistia stratiotes), hydrilla (Hydrilla verticillata) and watercress (Lepidium sativum) have been studied to investigate their arsenic uptake ability and mechanisms, and to evaluate their potential in phytoremediation technology. It has been suggested that the aquatic macrophytes would be potential for arsenic phytoremediation, and this paper reviews up to date knowledge on arsenic phytoremediation by common aquatic macrophytes.

  13. Map showing bathymetry and aquatic plants of Lake Waramaug, Connecticut

    USGS Publications Warehouse

    Kulp, Kenneth P.

    1981-01-01

    The Bathymetry of Lake Waramaug is shown at 5-foot intervals, and the location and identification of significant concentrations of aquatic plants is indicated. The bathymetry shows the lake to be relatively steep-sided and flat-bottomed, with a maximum depth of between 40 and 45 feet. Aquatic plants were confined to the edges of the lake in depths of less than 15 feet. Nine species of aquatic plants occcur in significant numbers in the lake. Lake bathymetric data were collected using a recording fathometer and sounding rod; aquatic plant data were collected by visual survey; and the collection of samples using a weed rake. (USGS)

  14. Using occupancy modelling to compare environmental DNA to traditional field methods for regional-scale monitoring of an endangered aquatic species.

    PubMed

    Schmelzle, Molly C; Kinziger, Andrew P

    2016-07-01

    Environmental DNA (eDNA) monitoring approaches promise to greatly improve detection of rare, endangered and invasive species in comparison with traditional field approaches. Herein, eDNA approaches and traditional seining methods were applied at 29 research locations to compare method-specific estimates of detection and occupancy probabilities for endangered tidewater goby (Eucyclogobius newberryi). At each location, multiple paired seine hauls and water samples for eDNA analysis were taken, ranging from two to 23 samples per site, depending upon habitat size. Analysis using a multimethod occupancy modelling framework indicated that the probability of detection using eDNA was nearly double (0.74) the rate of detection for seining (0.39). The higher detection rates afforded by eDNA allowed determination of tidewater goby occupancy at two locations where they have not been previously detected and at one location considered to be locally extirpated. Additionally, eDNA concentration was positively related to tidewater goby catch per unit effort, suggesting eDNA could potentially be used as a proxy for local tidewater goby abundance. Compared to traditional field sampling, eDNA provided improved occupancy parameter estimates and can be applied to increase management efficiency across a broad spatial range and within a diversity of habitats.

  15. Biochemical responses of the aquatic higher plant Lemna gibba to a mixture of copper and 1,2-dihydroxyanthraquinone: synergistic toxicity via reactive oxygen species.

    PubMed

    Babu, T Sudhakar; Tripuranthakam, Sridevi; Greenberg, Bruce M

    2005-12-01

    Metals and polycyclic aromatic hydrocarbons (PAHs) are known to be toxic to plants. Because metals and PAHs often are cocontaminants in the environment, plants can be subjected to damage caused by their combined effects. We recently found that copper and an oxygenated PAH (1,2-dihydroxyanthraquinone [1,2-dhATQ]) synergistically are toxic to plants. This synergistic toxicity was linked indirectly to production of reactive oxygen species (ROS). In this study, plant growth, chlorophyll pigments, protein accumulation, and ROS production were chosen as endpoints to assess the mechanism of toxicity of copper and 1,2-dhATQ to Lemna gibba in more detail. Because copper and PAHs can generate ROS, we assayed for specific antioxidant enzymes: Superoxide dismutase (SOD), glutathione reductase (GR), and ascorbate peroxidase (APX). Copper treatment at a concentration that did not cause growth inhibition resulted in upregulation of Mn SOD, Cu-Zn SOD, and APX. At a level that moderately was toxic to plants, 1,2-dhATQ did not alter significantly the levels of these antioxidant enzymes. However, a synergistically toxic mixture of copper plus 1,2-dhATQ upregulated Cu-Zn SOD, Mn SOD, and GR, although APX activity was downregulated. When plants were treated with the ROS scavenger dimethyl thiourea (DMTU), enhanced toxicity and formation of ROS caused by the mixture both were diminished substantially. However, 1,2-dhATQ toxicity was not affected significantly by DMTU. Based on this study, the toxicity caused by the mixture of copper plus 1,2-dhATQ directly can be connected to elevated levels of ROS. PMID:16445081

  16. Respiration in Aquatic Insects.

    ERIC Educational Resources Information Center

    MacFarland, John

    1985-01-01

    This article: (1) explains the respiratory patterns of several freshwater insects; (2) describes the differences and mechanisms of spiracular cutaneous, and gill respiration; and (3) discusses behavioral aspects of selected aquatic insects. (ML)

  17. Trace element accumulation in aquatic plants: a literature review

    SciTech Connect

    Ganje, T.J.; Elseewi, A.A.; Page, A.L.

    1988-01-01

    Trace elements in sediments and its overlying waters are important constituents of an aquatic plant ecosystem. This review was undertaken to evaluate trace element accumulation in aquatic plants and ascertain to what extent sediment and its overlying waters play in trace element accumulation by aquatic plant species. Aquatic vascular plants tend to accumulate trace elements in relation to the trace element concentration of the water body and sediment in which they are grown and the extent of exposure to the water body. Trace element composition of bryophytes and algae is also closely related to composition of their aquatic environment. It is increasingly apparent that sediments and overlying waters alter the bioavailability of trace elements to aquatic plants in both natural and artificial water bodies, particularly where industrial and agricultural waters are discharged into waterways.

  18. The Aquatic Systems Continuum

    NASA Astrophysics Data System (ADS)

    Winter, T. C.

    2004-12-01

    The Aquatic Systems Continuum is a proposed framework for interrelating the physical, chemical, and biological characteristics of aquatic ecosystems. The continuum can be represented by a three-dimensional matrix that relates aquatic ecosystems to their position within hydrologic flow paths (x-axis, a spatial dimension) and their response to climate variability (y-axis). The z-axis describes the structure of biological communities as they relate to the hydrological conditions defined by the x and y axes. The concept is an extension of the Wetland Continuum that was derived from field studies of a prairie pothole wetland complex in North Dakota. At that site, the hydrologic continuum in space is defined by ground-water flow systems. The wetlands are surface-water expressions of larger ground-water watersheds, in which wetlands serve recharge, flow-through, and discharge functions with respect to ground water. The water balance of the wetlands is dominated by precipitation and evaporation. However, the interaction of the wetlands with ground water, although a small part of their water budget, provides the primary control on delivery of major solutes to and from the wetlands. Having monitored these wetlands for more than 25 years, during which time the site had a complete range of climate conditions from drought to deluge, the response of the aquatic communities to a wide variety of climate conditions has been well documented. The Aquatic Systems Continuum extends the model provided by the Wetland Continuum to include rivers and their interaction with ground water. As a result, both ground water and surface water are used to describe terrestrial water flows for all types of aquatic ecosystems. By using the Aquatic Systems Continuum to describe the hydrologic flow paths in all types of terrain, including exchange with atmospheric water, it is possible to design studies, monitoring programs, and management plans for nearly any type of aquatic ecosystem.

  19. Aquatic toxicology: fact or fiction

    SciTech Connect

    Macek, K.J.

    1980-02-01

    The science of aquatic toxicology is a relatively new science. The development of the field of aquatic toxicology since 1930 is traced. The state of the art of aquatic toxicology compared with that of classical toxicology is evaluated. The science of aquatic toxicology is expected to undergo a significant period of rapid growth and development, leading ultimately to the formation of a mature science.

  20. Measuring titratable alkalinity by single versus double endpoint titration: An evaluation in two cyprinodont species and implications for characterizing net H+ flux in aquatic organisms.

    PubMed

    Brix, Kevin V; Wood, Chris M; Grosell, Martin

    2013-01-01

    effectively zero in both species at pH 4.5. However, significant differences between the double endpoint (no net H(+) transport at low pH) and single endpoint titrations (net H(+) uptake at low pH) remain to be explained.

  1. CAM Photosynthesis in Submerged Aquatic Plants

    USGS Publications Warehouse

    Keeley, J.E.

    1998-01-01

    Crassulacean acid metabolism (CAM) is a CO2-concentrating mechanism selected in response to aridity in terrestrial habitats, and, in aquatic environments, to ambient limitations of carbon. Evidence is reviewed for its presence in five genera of aquatic vascular plants, including Isoe??tes, Sagittaria, Vallisneria, Crassula, and Littorella. Initially, aquatic CAM was considered by some to be an oxymoron, but some aquatic species have been studied in sufficient detail to say definitively that they possess CAM photosynthesis. CO2-concentrating mechanisms in photosynthetic organs require a barrier to leakage; e.g., terrestrial C4 plants have suberized bundle sheath cells and terrestrial CAM plants high stomatal resistance. In aquatic CAM plants the primary barrier to CO2 leakage is the extremely high diffusional resistance of water. This, coupled with the sink provided by extensive intercellular gas space, generates daytime CO2(Pi) comparable to terrestrial CAM plants. CAM contributes to the carbon budget by both net carbon gain and carbon recycling, and the magnitude of each is environmentally influenced. Aquatic CAM plants inhabit sites where photosynthesis is potentially limited by carbon. Many occupy moderately fertile shallow temporary pools that experience extreme diel fluctuations in carbon availability. CAM plants are able to take advantage of elevated nighttime CO2 levels in these habitats. This gives them a competitive advantage over non-CAM species that are carbon starved during the day and an advantage over species that expend energy in membrane transport of bicarbonate. Some aquatic CAM plants are distributed in highly infertile lakes, where extreme carbon limitation and light are important selective factors. Compilation of reports on diel changes in titratable acidity and malate show 69 out of 180 species have significant overnight accumulation, although evidence is presented discounting CAM in some. It is concluded that similar proportions of the aquatic

  2. Aquatic macrophyte diversity of the Pantanal wetland and upper basin.

    PubMed

    Pott, V J; Pott, A; Lima, L C P; Moreira, S N; Oliveira, A K M

    2011-04-01

    This is a short review of the state of the art concerning diversity of aquatic macrophytes and the main aquatic vegetation types in the Brazilian Pantanal wetland and upper watershed. There are ca. 280 species of aquatic macrophytes on the Pantanal floodplain, with scarce endemism. On the upper watershed, Cerrado wetlands (veredas) and limestone springs have a distinct flora from the Pantanal, with twice the species richness. As a representative case of aquatic habitats influenced by river flood, some primary data are presented for the Pantanal Matogrossense National Park and associated Acurizal Preserve, analysing the floristic similarity among aquatic vegetation types. We comment on problems of conservation and observe that Panicum elephantipes Nees is one of the few natives to compete with the invasive Urochloa arrecta (Hack. ex T. Durand & Schinz) Morrone & Zuloaga.

  3. Convergence and divergence in the evolution of aquatic birds.

    PubMed

    Van Tuinen, M; Butvill, D B; Kirsch, J A; Hedges, S B

    2001-07-01

    Aquatic birds exceed other terrestrial vertebrates in the diversity of their adaptations to aquatic niches. For many species this has created difficulty in understanding their evolutionary origin and, in particular, for the flamingos, hamerkop, shoebill and pelecaniforms. Here, new evidence from nuclear and mitochondrial DNA sequences and DNA-DNA hybridization data indicates extensive morphological convergence and divergence in aquatic birds. Among the unexpected findings is a grouping of flamingos and grebes, species which otherwise show no resemblance. These results suggest that the traditional characters used to unite certain aquatic groups, such as totipalmate feet, foot-propelled diving and long legs, evolved more than once and that organismal change in aquatic birds has proceeded at a faster pace than previously recognized. PMID:11429133

  4. Convergence and divergence in the evolution of aquatic birds.

    PubMed Central

    Van Tuinen, M.; Butvill, D. B.; Kirsch, J. A.; Hedges, S. B.

    2001-01-01

    Aquatic birds exceed other terrestrial vertebrates in the diversity of their adaptations to aquatic niches. For many species this has created difficulty in understanding their evolutionary origin and, in particular, for the flamingos, hamerkop, shoebill and pelecaniforms. Here, new evidence from nuclear and mitochondrial DNA sequences and DNA-DNA hybridization data indicates extensive morphological convergence and divergence in aquatic birds. Among the unexpected findings is a grouping of flamingos and grebes, species which otherwise show no resemblance. These results suggest that the traditional characters used to unite certain aquatic groups, such as totipalmate feet, foot-propelled diving and long legs, evolved more than once and that organismal change in aquatic birds has proceeded at a faster pace than previously recognized. PMID:11429133

  5. Convergence and divergence in the evolution of aquatic birds.

    PubMed

    Van Tuinen, M; Butvill, D B; Kirsch, J A; Hedges, S B

    2001-07-01

    Aquatic birds exceed other terrestrial vertebrates in the diversity of their adaptations to aquatic niches. For many species this has created difficulty in understanding their evolutionary origin and, in particular, for the flamingos, hamerkop, shoebill and pelecaniforms. Here, new evidence from nuclear and mitochondrial DNA sequences and DNA-DNA hybridization data indicates extensive morphological convergence and divergence in aquatic birds. Among the unexpected findings is a grouping of flamingos and grebes, species which otherwise show no resemblance. These results suggest that the traditional characters used to unite certain aquatic groups, such as totipalmate feet, foot-propelled diving and long legs, evolved more than once and that organismal change in aquatic birds has proceeded at a faster pace than previously recognized.

  6. 40 CFR 158.243 - Experimental use permit data requirements for terrestrial and aquatic nontarget organisms.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... toxicity R R R NR NR NR TGAI, TEP 1, 2, 5, 6, 11 850.1010 Acute toxicity freshwater invertebrates R R R NR NR NR TGAI, TEP 1, 2, 6, 7, 11 850.1300 Aquatic invertebrate life cycle (freshwater) NR R R NR NR NR... aquatic organisms. 7. Data are required on one freshwater aquatic invertebrate species. 8. Data...

  7. 40 CFR 158.243 - Experimental use permit data requirements for terrestrial and aquatic nontarget organisms.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... toxicity R R R NR NR NR TGAI, TEP 1, 2, 5, 6, 11 850.1010 Acute toxicity freshwater invertebrates R R R NR NR NR TGAI, TEP 1, 2, 6, 7, 11 850.1300 Aquatic invertebrate life cycle (freshwater) NR R R NR NR NR... aquatic organisms. 7. Data are required on one freshwater aquatic invertebrate species. 8. Data...

  8. 40 CFR 158.243 - Experimental use permit data requirements for terrestrial and aquatic nontarget organisms.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... toxicity R R R NR NR NR TGAI, TEP 1, 2, 5, 6, 11 850.1010 Acute toxicity freshwater invertebrates R R R NR NR NR TGAI, TEP 1, 2, 6, 7, 11 850.1300 Aquatic invertebrate life cycle (freshwater) NR R R NR NR NR... aquatic organisms. 7. Data are required on one freshwater aquatic invertebrate species. 8. Data...

  9. 40 CFR 158.243 - Experimental use permit data requirements for terrestrial and aquatic nontarget organisms.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... toxicity R R R NR NR NR TGAI, TEP 1, 2, 5, 6, 11 850.1010 Acute toxicity freshwater invertebrates R R R NR NR NR TGAI, TEP 1, 2, 6, 7, 11 850.1300 Aquatic invertebrate life cycle (freshwater) NR R R NR NR NR... aquatic organisms. 7. Data are required on one freshwater aquatic invertebrate species. 8. Data...

  10. 40 CFR 158.243 - Experimental use permit data requirements for terrestrial and aquatic nontarget organisms.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... toxicity R R R NR NR NR TGAI, TEP 1, 2, 5, 6, 11 850.1010 Acute toxicity freshwater invertebrates R R R NR NR NR TGAI, TEP 1, 2, 6, 7, 11 850.1300 Aquatic invertebrate life cycle (freshwater) NR R R NR NR NR... aquatic organisms. 7. Data are required on one freshwater aquatic invertebrate species. 8. Data...

  11. Are pharmaceuticals more harmful than other pollutants to aquatic invertebrate species: a hypothesis tested using multi-biomarker and multi-species responses in field collected and transplanted organisms.

    PubMed

    Damásio, Joana; Barceló, Damià; Brix, Rikke; Postigo, Cristina; Gros, Meritxell; Petrovic, Mira; Sabater, Sergi; Guasch, Helena; de Alda, Miren Lopez; Barata, Carlos

    2011-11-01

    The aim of this study was to test if pharmaceuticals could explain observed responses of field collected and transplanted invertebrate species (Hydropsyche exocellata, Echinogammarus longisetosus, and Daphnia magna). The study was performed in the middle and lower course of Llobregat river basin, which is affected by pharmaceuticals and other pollutants coming from sewage treated effluents. Up to 10 different endpoints including enzyme activities related with detoxication mechanisms (i.e. glutathione S transferase, catalase, esterases), the oxidative stress damage marker (lipid peroxidation), and individual responses (mortality, post-exposure feeding rates) were assessed. Biological responses were complemented with a detailed chemical analysis of metals, detergents, pesticides, pharmaceuticals and other general water quality variables to allow identifying causal abiotic factors. Estimated hazard indexes of measured pollutants indicated that pesticides and metals accounted for most of the predicted toxicity (>95%) in the most contaminated site and that the predicted toxicity of pharmaceuticals was marginal (<5%). The three species showed a clear impact across the studied gradient indicated by higher levels of feeding inhibition and of mortality towards lower reaches. Specific responses such as inhibition of cholinesterase activities were closely related to high and presumable toxic levels of diazinon, whereas unspecific responses such as enhanced levels of antioxidant defensive mechanism and of lipid peroxidation levels were associated with most pollutant classes as well as with high and presumable toxic levels of salt and ammonia. These results indicate that pesticides, salinity, ammonia probably had greater effects on the studied species than pharmaceuticals. PMID:21925701

  12. Nutrition, illness, and injury in aquatic sports.

    PubMed

    Pyne, David B; Verhagen, Evert A; Mountjoy, Margo

    2014-08-01

    In this review, we outline key principles for prevention of injury and illness in aquatic sports, detail the epidemiology of injury and illness in aquatic athletes at major international competitions and in training, and examine the relevant scientific evidence on nutrients for reducing the risk of illness and injury. Aquatic athletes are encouraged to consume a well-planned diet with sufficient calories, macronutrients (particularly carbohydrate and protein), and micronutrients (particularly iron, zinc, and vitamins A, D, E, B6, and B12) to maintain health and performance. Ingesting carbohydrate via sports drinks, gels, or sports foods during prolonged training sessions is beneficial in maintaining energy availability. Studies of foods or supplements containing plant polyphenols and selected strains of probiotic species are promising, but further research is required. In terms of injury, intake of vitamin D, protein, and total caloric intake, in combination with treatment and resistance training, promotes recovery back to full health and training.

  13. Beaver herbivory on aquatic plants.

    PubMed

    Parker, John D; Caudill, Christopher C; Hay, Mark E

    2007-04-01

    Herbivores have strong impacts on marine and terrestrial plant communities, but their impact is less well studied in benthic freshwater systems. For example, North American beavers (Castor canadensis) eat both woody and non-woody plants and focus almost exclusively on the latter in summer months, yet their impacts on non-woody plants are generally attributed to ecosystem engineering rather than herbivory. Here, we excluded beavers from areas of two beaver wetlands for over 2 years and demonstrated that beaver herbivory reduced aquatic plant biomass by 60%, plant litter by 75%, and dramatically shifted plant species composition. The perennial forb lizard's tail (Saururus cernuus) comprised less than 5% of plant biomass in areas open to beaver grazing but greater than 50% of plant biomass in beaver exclusions. This shift was likely due to direct herbivory, as beavers preferentially consumed lizard's tail over other plants in a field feeding assay. Beaver herbivory also reduced the abundance of the invasive aquatic plant Myriophyllum aquaticum by nearly 90%, consistent with recent evidence that native generalist herbivores provide biotic resistance against exotic plant invasions. Beaver herbivory also had indirect effects on plant interactions in this community. The palatable plant lizard's tail was 3 times more frequent and 10 times more abundant inside woolgrass (Scirpus cyperinus) tussocks than in spatially paired locations lacking tussocks. When the protective foliage of the woolgrass was removed without exclusion cages, beavers consumed nearly half of the lizard's tail leaves within 2 weeks. In contrast, leaf abundance increased by 73-93% in the treatments retaining woolgrass or protected by a cage. Thus, woolgrass tussocks were as effective as cages at excluding beaver foraging and provided lizard's tail plants an associational refuge from beaver herbivory. These results suggest that beaver herbivory has strong direct and indirect impacts on populations and

  14. Current status of aquatic species biologics.

    PubMed

    Haskell, Scott R R; Carberry-Goh, Karen; Payne, Michael A; Smith, Stephen A

    2004-11-15

    No vaccine is a substitute for good management and diligent biosecurity in an aquaculture facility. It is always important to ensure the best water quality possible, provide quality nutrition, avoid overcrowding of tanks and raceways, remove dead fish to prevent pathogen buildup and spread, and reduce or eliminate unnecessary stress on fish. Use of a preventive medicine vaccine program and improved management can help ensure good health in a fish population and reduce the industries' use of therapeutic agents.

  15. Science to support aquatic animal health

    USGS Publications Warehouse

    Purcell, Maureen K.; Harris, M. Camille

    2016-10-18

    Healthy aquatic ecosystems are home to a diversity of plants, invertebrates, fish and wildlife. Aquatic animal populations face unprecedented threats to their health and survival from climate change, water shortages, habitat alteration, invasive species and environmental contaminants. These environmental stressors can directly impact the prevalence and severity of disease in aquatic populations. For example, periodic fish kills in the upper Chesapeake Bay Watershed are associated with many different opportunistic pathogens that proliferate in stressed fish populations. An estimated 80 percent of endangered juvenile Puget Sound steelhead trout die within two weeks of entering the marine environment, and a role for disease in these losses is being investigated. The introduction of viral hemorrhagic septicemia virus (VHSV) into the Great Lakes—a fishery worth an estimated 7 billion dollars annually—resulted in widespread fish die-offs and virus detections in 28 different fish species. Millions of dying sea stars along the west coast of North America have led to investigations into sea star wasting disease. U.S. Geological Survey (USGS) scientists are assisting managers with these issues through ecological investigations of aquatic animal diseases, field surveillance, and research to promote the development of mitigation strategies.

  16. Science to Support Aquatic Animal Health

    USGS Publications Warehouse

    Purcell, Maureen K.; Harris, M. Camille

    2016-10-18

    Healthy aquatic ecosystems are home to a diversity of plants, invertebrates, fish and wildlife. Aquatic animal populations face unprecedented threats to their health and survival from climate change, water shortages, habitat alteration, invasive species and environmental contaminants. These environmental stressors can directly impact the prevalence and severity of disease in aquatic populations. For example, periodic fish kills in the upper Chesapeake Bay Watershed are associated with many different opportunistic pathogens that proliferate in stressed fish populations. An estimated 80 percent of endangered juvenile Puget Sound steelhead trout die within two weeks of entering the marine environment, and a role for disease in these losses is being investigated. The introduction of viral hemorrhagic septicemia virus (VHSV) into the Great Lakes—a fishery worth an estimated 7 billion dollars annually—resulted in widespread fish die-offs and virus detections in 28 different fish species. Millions of dying sea stars along the west coast of North America have led to investigations into sea star wasting disease. U.S. Geological Survey (USGS) scientists are assisting managers with these issues through ecological investigations of aquatic animal diseases, field surveillance, and research to promote the development of mitigation strategies.

  17. Predatory aquatic beetles, suitable trace elements bioindicators.

    PubMed

    Burghelea, Carmen I; Zaharescu, Dragos G; Hooda, Peter S; Palanca-Soler, Antonio

    2011-05-01

    Predatory aquatic beetles are common colonizers of natural and managed aquatic environments. While as important components of the aquatic food webs they are prone to accumulate trace elements, they have been largely neglected from metal uptake studies. We aim to test the suitability of three dytiscid species, i.e.Hydroglyphus pusillus, Laccophilus minutus and Rhantus suturalis, as trace elements (Al, As, Cd, Co, Cu, Fe, Mn, Mo, Ni, Pb, Se and Zn) bioindicators. The work was carried out in a case area representing rice paddies and control sites (reservoirs) from an arid region known for its land degradation (Monegros, NE Spain). Categorical principal component analysis (CATPCA) was tested as a nonlinear approach to identify significant relationships between metals, species and habitat conditions so as to examine the ability of these species to reflect differences in metal uptake. Except Se and As, the average concentrations of all other elements in the beetles were higher in the rice fields than in the control habitats. The CATPCA determined that H. pusillus had high capacity to accumulate Fe, Ni and Mn regardless of the habitat type, and hence may not be capable of distinguishing habitat conditions with regards to these metals. On the other hand, L. minutus was found less sensitive for Se in non-managed habitats (i.e. reservoirs), while R. suturalis was good in accumulating Al, Mo and Pb in rice fields. The latter seems to be a promising bioindicator of metal enrichment in rice fields. We conclude that predatory aquatic beetles are good candidates for trace elements bioindication in impacted and non-impacted environments and can be used in environmental monitoring studies. CATPCA proved to be a reliable approach to unveil trends in metal accumulation in aquatic invertebrates according to their habitat status.

  18. Aquatic Microbiology Laboratory Manual.

    ERIC Educational Resources Information Center

    Cooper, Robert C.; And Others

    This laboratory manual presents information and techniques dealing with aquatic microbiology as it relates to environmental health science, sanitary engineering, and environmental microbiology. The contents are divided into three categories: (1) ecological and physiological considerations; (2) public health aspects; and (3)microbiology of water…

  19. Aquatic Resources Education Curriculum.

    ERIC Educational Resources Information Center

    Pfeiffer, C. Boyd; Sosin, Mark

    Fishing is one of the oldest and most popular outdoor activities. Like most activities, fishing requires basic knowledge and skill for success. The Aquatic Resources Education Curriculum is designed to assist beginning anglers in learning the basic concepts of how, when, and where to fish as well as what tackle to use. The manual is designed to be…

  20. Investigating Aquatic Dead Zones

    ERIC Educational Resources Information Center

    Testa, Jeremy; Gurbisz, Cassie; Murray, Laura; Gray, William; Bosch, Jennifer; Burrell, Chris; Kemp, Michael

    2010-01-01

    This article features two engaging high school activities that include current scientific information, data, and authentic case studies. The activities address the physical, biological, and chemical processes that are associated with oxygen-depleted areas, or "dead zones," in aquatic systems. Students can explore these dead zones through both…

  1. Aquatic Equipment Information.

    ERIC Educational Resources Information Center

    Sova, Ruth

    Equipment usually used in water exercise programs is designed for variety, intensity, and program necessity. This guide discusses aquatic equipment under the following headings: (1) equipment design; (2) equipment principles; (3) precautions and contraindications; (4) population contraindications; and (5) choosing equipment. Equipment is used…

  2. Aquatic plant management

    SciTech Connect

    Not Available

    1991-01-01

    Twelve fact sheets are presented which cover different forms of aquatic plant management in Guntersville Reservoir. These cover the introduction of grass carp and other biological controls, drawdown of reservoir water, herbicide use, harvesting, impacts on recreational uses, and other issues of concern. (SM)

  3. Contaminated Aquatic Sediments.

    PubMed

    Jaglal, Kendrick

    2016-10-01

    A review of the literature published in 2015 relating to the assessment, evaluation and remediation of contaminated aquatic sediments is presented. The review is divided into the following main sections: policy and guidance, methodology, distribution, fate and transport, risk, toxicity and remediation. PMID:27620103

  4. Methods for Aquatic Resource Assessment

    EPA Science Inventory

    The Methods for Aquatic Resource Assessment (MARA) project consists of three main activities in support of assessing the conditions of the nation’s aquatic resources: 1) scientific support for EPA Office of Water’s national aquatic resource surveys; 2) spatial predications of riv...

  5. Aquatic Plants and their Control.

    ERIC Educational Resources Information Center

    Michigan State Dept. of Natural Resources, Lansing.

    Aquatic plants can be divided into two types: algae and macrophytes. The goal of aquatic plant management is to maintain a proper balance of plants within a lake and still retain the lake's recreational and economic importance. Aquatic plant management programs have two phases: long-term management (nutrient control), and short-term management…

  6. Proceedings of aquatic toxicology and hazard assessment

    SciTech Connect

    Cowgill, U.M.

    1989-01-01

    This book contains the proceeding of Aquatic toxicology and hazard assessment. During the past twelve year, the aquatic toxicology group (Subcommittee E47.01) of ASTM has sponsored an annual symposium for the major purpose of bring together aquatic specialists from industry, government, and academe. The end result of these gatherings has been a debate on the merits of test development, animal and plant culture, nutrition and testing, and, last but not least, the lack of interagency harmony. The underlying intent of the 12th Symposium on Aquatic Toxicology and Hazard Assessment was to hold sessions devoted to updating all the various subfields of aquatic toxicology. Thus, the meeting began with a discussion of the benefits of interagency harmonization, which was largely devoted to the need for unity among the various regulatory bodies devoted to protecting the environment. Reviews of common modes of toxic action, target toxicant analysis, and field techniques offered a forum for discussion on advances that have occurred in these fields since the last deliberation on these topics some symposia ago. The problems associated with statistical interpretation of the results of microcosm testing occupied a full session. New approaches in sediment toxicity testing, the culturing and testing of new organisms, exclusively marine, and the never-ending association between nutrition and testing were brought up to date in several minisymposia. A session was devoted to quality assurance in ectotoxicity testing, which is represented in is symposium volume by a discussion of the New Jersey laboratory certification program. The symposium closed wit a heavy attendance at a session on toxicity testing problems involving effluents.

  7. Fisheries and aquatic resources--fish health

    USGS Publications Warehouse

    Panek, Frank

    2008-01-01

    Fish health research at Leetown had its origin in the 1930’s when the Leetown Fish Hatchery and Experiment Station was constructed. In 1978, the National Fish Health Research Laboratory, now a component of the Leetown Science Center, was established to solve emerging and known disease problems affecting fish and other aquatic organisms critical to species restoration programs. Center scientists develop methods for the isolation, detection, and identification of fish pathogens and for prevention and control of fish diseases.

  8. Fraser River action plan: Aquatic science

    SciTech Connect

    1998-12-31

    Reviews research carried out under the Fraser River Action Plan in the field of aquatic science, beginning with research carried out on Fraser River headwater lakes and the contaminants found in those lakes and their fish. Subsequent sections cover research on sediment and contaminant transport, benthic communities, fish species distribution, contaminants in fish, pollution sources (from urban runoff, agriculture, and forestry), pollution in the Fraser estuary, and environmental indicators.

  9. Does aquatic foraging impact head shape evolution in snakes?

    PubMed

    Segall, Marion; Cornette, Raphaël; Fabre, Anne-Claire; Godoy-Diana, Ramiro; Herrel, Anthony

    2016-08-31

    Evolutionary trajectories are often biased by developmental and historical factors. However, environmental factors can also impose constraints on the evolutionary trajectories of organisms leading to convergence of morphology in similar ecological contexts. The physical properties of water impose strong constraints on aquatic feeding animals by generating pressure waves that can alert prey and potentially push them away from the mouth. These hydrodynamic constraints have resulted in the independent evolution of suction feeding in most groups of secondarily aquatic tetrapods. Despite the fact that snakes cannot use suction, they have invaded the aquatic milieu many times independently. Here, we test whether the aquatic environment has constrained head shape evolution in snakes and whether shape converges on that predicted by biomechanical models. To do so, we used three-dimensional geometric morphometrics and comparative, phylogenetically informed analyses on a large sample of aquatic snake species. Our results show that aquatic snakes partially conform to our predictions and have a narrower anterior part of the head and dorsally positioned eyes and nostrils. This morphology is observed, irrespective of the phylogenetic relationships among species, suggesting that the aquatic environment does indeed drive the evolution of head shape in snakes, thus biasing the evolutionary trajectory of this group of animals. PMID:27581887

  10. Does aquatic foraging impact head shape evolution in snakes?

    PubMed

    Segall, Marion; Cornette, Raphaël; Fabre, Anne-Claire; Godoy-Diana, Ramiro; Herrel, Anthony

    2016-08-31

    Evolutionary trajectories are often biased by developmental and historical factors. However, environmental factors can also impose constraints on the evolutionary trajectories of organisms leading to convergence of morphology in similar ecological contexts. The physical properties of water impose strong constraints on aquatic feeding animals by generating pressure waves that can alert prey and potentially push them away from the mouth. These hydrodynamic constraints have resulted in the independent evolution of suction feeding in most groups of secondarily aquatic tetrapods. Despite the fact that snakes cannot use suction, they have invaded the aquatic milieu many times independently. Here, we test whether the aquatic environment has constrained head shape evolution in snakes and whether shape converges on that predicted by biomechanical models. To do so, we used three-dimensional geometric morphometrics and comparative, phylogenetically informed analyses on a large sample of aquatic snake species. Our results show that aquatic snakes partially conform to our predictions and have a narrower anterior part of the head and dorsally positioned eyes and nostrils. This morphology is observed, irrespective of the phylogenetic relationships among species, suggesting that the aquatic environment does indeed drive the evolution of head shape in snakes, thus biasing the evolutionary trajectory of this group of animals.

  11. Scaling macroscopic aquatic locomotion

    NASA Astrophysics Data System (ADS)

    Gazzola, Mattia; Argentina, Médéric; Mahadevan, L.

    2014-10-01

    Inertial aquatic swimmers that use undulatory gaits range in length L from a few millimetres to 30 metres, across a wide array of biological taxa. Using elementary hydrodynamic arguments, we uncover a unifying mechanistic principle characterizing their locomotion by deriving a scaling relation that links swimming speed U to body kinematics (tail beat amplitude A and frequency ω) and fluid properties (kinematic viscosity ν). This principle can be simply couched as the power law Re ~ Swα, where Re = UL/ν >> 1 and Sw = ωAL/ν, with α = 4/3 for laminar flows, and α = 1 for turbulent flows. Existing data from over 1,000 measurements on fish, amphibians, larvae, reptiles, mammals and birds, as well as direct numerical simulations are consistent with our scaling. We interpret our results as the consequence of the convergence of aquatic gaits to the performance limits imposed by hydrodynamics.

  12. Scaling macroscopic aquatic locomotion

    NASA Astrophysics Data System (ADS)

    Gazzola, Mattia; Argentina, Mederic; Mahadevan, Lakshminarayanan

    2014-11-01

    Inertial aquatic swimmers that use undulatory gaits range in length L from a few millimeters to 30 meters, across a wide array of biological taxa. Using elementary hydrodynamic arguments, we uncover a unifying mechanistic principle characterizing their locomotion by deriving a scaling relation that links swimming speed U to body kinematics (tail beat amplitude A and frequency ω) and fluid properties (kinematic viscosity ν). This principle can be simply couched as the power law Re ~ Swα , where Re = UL / ν >> 1 and Sw = ωAL / ν , with α = 4 / 3 for laminar flows, and α = 1 for turbulent flows. Existing data from over 1000 measurements on fish, amphibians, larvae, reptiles, mammals and birds, as well as direct numerical simulations are consistent with our scaling. We interpret our results as the consequence of the convergence of aquatic gaits to the performance limits imposed by hydrodynamics.

  13. Pro-oxidant and antioxidant processes in aquatic invertebrates.

    PubMed

    Canesi, Laura

    2015-03-01

    Most aquatic organisms behave as conformers with respect to environmental variables, including changes in O2 availability. Aquatic species that show tolerance to hypoxia/anoxia or hyperoxia can be excellent models for investigating physiological and biochemical adaptations that deal with changing O2 and consequent changes in metabolic rate and production of reactive oxygen species (ROS). Here, I summarize selected data on ROS production and antioxidant defenses in a model marine invertebrate, the bivalve Mytilus, under different environmental and physiological conditions. An example of other bivalves adapted to particular environments (the Antarctic Sea) is also reported. These studies contributed to the knowledge on pro-oxidant and antioxidant processes in aquatic invertebrates from comparative and environmental perspectives. A common role for metallothioneins in antioxidant protection in mammals and aquatic invertebrates is underlined in different conditions, from human disease to responses to environmental exposure to heavy metals.

  14. Aquatic versus mammalian toxicology: applications of the comparative approach

    SciTech Connect

    Guarino, A.M.

    1987-04-01

    The large body of literature and techniques generated by mammalian toxicity studies provides a conceptual and technical framework within which the absorption, fate, and disposition of xenobiotics in aquatic organisms can be studied. This review emphasizes the similarities and differences between mammalian and aquatic systems, e.g., lung vs. gill as site of absorption and toxicity. These must be taken into consideration when designing aquatic toxicity studies. Studies of phenol red in dogfish shark as an example show physiologic-based pharmacokinetic modeling to be a useful tool for investigating and eventually predicting species differences in xenobiotic disposition and drug differences within the same species. This discussion demonstrates that both laboratory and modeling procedures are now available to carry out sophisticated studies of xenobiotic fate and disposition in fish. Such studies are needed to pinpoint sites and mechanisms of pollutant toxicity in aquatic organisms.

  15. Aquatic Acoustic Metrics Interface

    SciTech Connect

    2012-12-18

    Fishes and marine mammals may suffer a range of potential effects from exposure to intense underwater sound generated by anthropogenic activities such as pile driving, shipping, sonars, and underwater blasting. Several underwater sound recording (USR) devices have been built to acquire samples of the underwater sound generated by anthropogenic activities. Software becomes indispensable for processing and analyzing the audio files recorded by these USRs. The new Aquatic Acoustic Metrics Interface Utility Software (AAMI) is specifically designed for analysis of underwater sound recordings to provide data in metrics that facilitate evaluation of the potential impacts of the sound on aquatic animals. In addition to the basic functions, such as loading and editing audio files recorded by USRs and batch processing of sound files, the software utilizes recording system calibration data to compute important parameters in physical units. The software also facilitates comparison of the noise sound sample metrics with biological measures such as audiograms of the sensitivity of aquatic animals to the sound, integrating various components into a single analytical frame.

  16. Aquatic Acoustic Metrics Interface

    2012-12-18

    Fishes and marine mammals may suffer a range of potential effects from exposure to intense underwater sound generated by anthropogenic activities such as pile driving, shipping, sonars, and underwater blasting. Several underwater sound recording (USR) devices have been built to acquire samples of the underwater sound generated by anthropogenic activities. Software becomes indispensable for processing and analyzing the audio files recorded by these USRs. The new Aquatic Acoustic Metrics Interface Utility Software (AAMI) is specificallymore » designed for analysis of underwater sound recordings to provide data in metrics that facilitate evaluation of the potential impacts of the sound on aquatic animals. In addition to the basic functions, such as loading and editing audio files recorded by USRs and batch processing of sound files, the software utilizes recording system calibration data to compute important parameters in physical units. The software also facilitates comparison of the noise sound sample metrics with biological measures such as audiograms of the sensitivity of aquatic animals to the sound, integrating various components into a single analytical frame.« less

  17. REPRODUCTIVE AND PHYSIOLOGICAL EFFECTS OF AQUATIC EXPOSURE TO TRENBOLONE, AN ENVIRONMENTAL ANDROGEN

    EPA Science Inventory

    Reproductive and Physiological Effects of Aquatic Exposure to Trenbolone, an Environmental Androgen (Abstract). To be presented at the 22nd Annual Meeting of the Society of Environmental Toxicology and Chemistry: Changing Environmental Awareness: Societal Concerns and Scientific...

  18. Cytochemical and ultrastructural aspects of aquatic carnivorous plant turions.

    PubMed

    Płachno, Bartosz J; Adamec, Lubomír; Kozieradzka-Kiszkurno, Małgorzata; Swiątek, Piotr; Kamińska, Iwona

    2014-11-01

    Turions, which are modified shoot apices, are vegetative, dormant overwintering organs produced by perennial aquatic plants. In this study, the turion cytochemistry and ultrastructure of Aldrovanda vesiculosa, Utricularia vulgaris and U. stygia were compared with particular emphasis placed on storage substances. These three aquatic, rootless carnivorous plant species were studied at the end of their winter dormancy. At this stage, the turions of all species had starch as their main storage material. In contrast with A. vesiculosa, Utricularia turions were rich in protein storage vacuoles, and proteins were also accumulated as crystalline inclusions in the nuclei. All examined species accumulated lipid droplets in cells of epidermal glands.

  19. Cytochemical and ultrastructural aspects of aquatic carnivorous plant turions.

    PubMed

    Płachno, Bartosz J; Adamec, Lubomír; Kozieradzka-Kiszkurno, Małgorzata; Swiątek, Piotr; Kamińska, Iwona

    2014-11-01

    Turions, which are modified shoot apices, are vegetative, dormant overwintering organs produced by perennial aquatic plants. In this study, the turion cytochemistry and ultrastructure of Aldrovanda vesiculosa, Utricularia vulgaris and U. stygia were compared with particular emphasis placed on storage substances. These three aquatic, rootless carnivorous plant species were studied at the end of their winter dormancy. At this stage, the turions of all species had starch as their main storage material. In contrast with A. vesiculosa, Utricularia turions were rich in protein storage vacuoles, and proteins were also accumulated as crystalline inclusions in the nuclei. All examined species accumulated lipid droplets in cells of epidermal glands. PMID:24770880

  20. Suitability of seagrasses and submerged aquatic vegetation as indicators of eutrophication

    EPA Science Inventory

    Rooted submerged aquatic vegetation (SAV) encompasses a large diversity of species that range from obligate halophytes such as, seagrasses, to euryhaline species and freshwater obligates. All seagrass and SAV provide key biological functions within the enclosed bays, estuaries, a...

  1. Early Pleistocene aquatic resource use in the Turkana Basin.

    PubMed

    Archer, Will; Braun, David R; Harris, Jack W K; McCoy, Jack T; Richmond, Brian G

    2014-12-01

    Evidence for the acquisition of nutritionally dense food resources by early Pleistocene hominins has implications for both hominin biology and behavior. Aquatic fauna may have comprised a source of highly nutritious resources to hominins in the Turkana Basin at ∼1.95 Ma. Here we employ multiple datasets to examine the issue of aquatic resource use in the early Pleistocene. This study focuses on four components of aquatic faunal assemblages (1) taxonomic diversity, (2) skeletal element proportion, (3) bone fragmentation and (4) bone surface modification. These components are used to identify associations between early Pleistocene aquatic remains and hominin behavior at the site of FwJj20 in the Koobi Fora Fm. (Kenya). We focus on two dominant aquatic species: catfish and turtles. Further we suggest that data on aquatic resource availability as well as ethnographic examples of aquatic resource use complement our observations on the archaeological remains from FwJj20. Aquatic food items provided hominins with a valuable nutritional alternative to an exclusively terrestrial resource base. We argue that specific advantages afforded by an aquatic alternative to terrestrial resources include (1) a probable reduction in required investment of energy relative to economic return in the form of nutritionally dense food items, (2) a decrease in the technological costs of resource acquisition, and (3) a reduced level of inter-specific competition associated with carcass access and an associated reduction of predation risk relative to terrestrial sources of food. The combined evidence from FwJj20 suggests that aquatic resources may have played a substantial role in early Pleistocene diets and these resources may have been overlooked in previous interpretations of hominin behavior.

  2. 40 CFR Appendix C to Part 122 - Criteria for Determining a Concentrated Aquatic Animal Production Facility (§ 122.24)

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... aquatic animals in either of the following categories: (a) Cold water fish species or other cold water... (approximately 100,000 pounds) of aquatic animals per year. “Cold water aquatic animals” include, but are not... ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) WATER PROGRAMS EPA ADMINISTERED PERMIT PROGRAMS: THE...

  3. 40 CFR Appendix C to Part 122 - Criteria for Determining a Concentrated Aquatic Animal Production Facility (§ 122.24)

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... aquatic animals in either of the following categories: (a) Cold water fish species or other cold water... (approximately 100,000 pounds) of aquatic animals per year. “Cold water aquatic animals” include, but are not... ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) WATER PROGRAMS EPA ADMINISTERED PERMIT PROGRAMS: THE...

  4. 40 CFR Appendix C to Part 122 - Criteria for Determining a Concentrated Aquatic Animal Production Facility (§ 122.24)

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... aquatic animals in either of the following categories: (a) Cold water fish species or other cold water... (approximately 100,000 pounds) of aquatic animals per year. “Cold water aquatic animals” include, but are not... ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) WATER PROGRAMS EPA ADMINISTERED PERMIT PROGRAMS: THE...

  5. 40 CFR Appendix C to Part 122 - Criteria for Determining a Concentrated Aquatic Animal Production Facility (§ 122.24)

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... aquatic animals in either of the following categories: (a) Cold water fish species or other cold water... (approximately 100,000 pounds) of aquatic animals per year. “Cold water aquatic animals” include, but are not... ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) WATER PROGRAMS EPA ADMINISTERED PERMIT PROGRAMS: THE...

  6. SETI meets a social intelligence: Dolphins as a model for real-time interaction and communication with a sentient species

    NASA Astrophysics Data System (ADS)

    Herzing, Denise L.

    2010-12-01

    In the past SETI has focused on the reception and deciphering of radio signals from potential remote civilizations. It is conceivable that real-time contact and interaction with a social intelligence may occur in the future. A serious look at the development of relationship, and deciphering of communication signals within and between a non-terrestrial, non-primate sentient species is relevant. Since 1985 a resident community of free-ranging Atlantic spotted dolphins has been observed regularly in the Bahamas. Life history, relationships, regular interspecific interactions with bottlenose dolphins, and multi-modal underwater communication signals have been documented. Dolphins display social communication signals modified for water, their body types, and sensory systems. Like anthropologists, human researchers engage in benign observation in the water and interact with these dolphins to develop rapport and trust. Many individual dolphins have been known for over 20 years. Learning the culturally appropriate etiquette has been important in the relationship with this alien society. To engage humans in interaction the dolphins often initiate spontaneous displays, mimicry, imitation, and synchrony. These elements may be emergent/universal features of one intelligent species contacting another for the intention of initiating interaction. This should be a consideration for real-time contact and interaction for future SETI work.

  7. Conceptual Framework for Aquatic Interfaces

    NASA Astrophysics Data System (ADS)

    Lewandowski, J.; Krause, S.

    2015-12-01

    Aquatic interfaces are generally characterized by steep gradients of physical, chemical and biological properties due to the contrast between the two adjacent environments. Innovative measurement techniques are required to study the spatially heterogeneous and temporally variable processes. Especially the different spatial and temporal scales are a large challenge. Due to the steep biogeochemical gradients and the intensive structural and compositional heterogeneity, enhanced biogeochemical processing rates are inherent to aquatic interfaces. Nevertheless, the effective turnover depends strongly on the residence time distribution along the flow paths and in sections with particular biogeochemical milieus and reaction kinetics. Thus, identification and characterization of the highly complex flow patterns in and across aquatic interfaces are crucial to understand biogeochemical processing along exchange flow paths and to quantify transport across aquatic interfaces. Hydrodynamic and biogeochemical processes are closely coupled at aquatic interfaces. However, interface processing rates are not only enhanced compared to the adjacent compartments that they connect; also completely different reactions might occur if certain thresholds are exceeded or the biogeochemical milieu differs significantly from the adjacent environments. Single events, temporal variability and spatial heterogeneity might increase overall processing rates of aquatic interfaces and thus, should not be neglected when studying aquatic interfaces. Aquatic interfaces are key zones relevant for the ecological state of the entire ecosystem and thus, understanding interface functioning and controls is paramount for ecosystem management. The overall aim of this contribution is a general conceptual framework for aquatic interfaces that is applicable to a wide range of systems, scales and processes.

  8. The Spemann organizer meets the anterior-most neuroectoderm at the equator of early gastrulae in amphibian species

    PubMed Central

    Yanagi, Takanori; Ito, Kenta; Nishihara, Akiha; Minamino, Reika; Mori, Shoko; Sumida, Masayuki; Hashimoto, Chikara

    2015-01-01

    The dorsal blastopore lip (known as the Spemann organizer) is important for making the body plan in amphibian gastrulation. The organizer is believed to involute inward and migrate animally to make physical contact with the prospective head neuroectoderm at the blastocoel roof of mid- to late-gastrula. However, we found that this physical contact was already established at the equatorial region of very early gastrula in a wide variety of amphibian species. Here we propose a unified model of amphibian gastrulation movement. In the model, the organizer is present at the blastocoel roof of blastulae, moves vegetally to locate at the region that lies from the blastocoel floor to the dorsal lip at the onset of gastrulation. The organizer located at the blastocoel floor contributes to the anterior axial mesoderm including the prechordal plate, and the organizer at the dorsal lip ends up as the posterior axial mesoderm. During the early step of gastrulation, the anterior organizer moves to establish the physical contact with the prospective neuroectoderm through the “subduction and zippering” movements. Subduction makes a trench between the anterior organizer and the prospective neuroectoderm, and the tissues face each other via the trench. Zippering movement, with forming Brachet's cleft, gradually closes the gap to establish the contact between them. The contact is completed at the equator of early gastrulae and it continues throughout the gastrulation. After the contact is established, the dorsal axis is formed posteriorly, but not anteriorly. The model also implies the possibility of constructing a common model of gastrulation among chordate species. PMID:25754292

  9. The Spemann organizer meets the anterior-most neuroectoderm at the equator of early gastrulae in amphibian species.

    PubMed

    Yanagi, Takanori; Ito, Kenta; Nishihara, Akiha; Minamino, Reika; Mori, Shoko; Sumida, Masayuki; Hashimoto, Chikara

    2015-04-01

    The dorsal blastopore lip (known as the Spemann organizer) is important for making the body plan in amphibian gastrulation. The organizer is believed to involute inward and migrate animally to make physical contact with the prospective head neuroectoderm at the blastocoel roof of mid- to late-gastrula. However, we found that this physical contact was already established at the equatorial region of very early gastrula in a wide variety of amphibian species. Here we propose a unified model of amphibian gastrulation movement. In the model, the organizer is present at the blastocoel roof of blastulae, moves vegetally to locate at the region that lies from the blastocoel floor to the dorsal lip at the onset of gastrulation. The organizer located at the blastocoel floor contributes to the anterior axial mesoderm including the prechordal plate, and the organizer at the dorsal lip ends up as the posterior axial mesoderm. During the early step of gastrulation, the anterior organizer moves to establish the physical contact with the prospective neuroectoderm through the "subduction and zippering" movements. Subduction makes a trench between the anterior organizer and the prospective neuroectoderm, and the tissues face each other via the trench. Zippering movement, with forming Brachet's cleft, gradually closes the gap to establish the contact between them. The contact is completed at the equator of early gastrulae and it continues throughout the gastrulation. After the contact is established, the dorsal axis is formed posteriorly, but not anteriorly. The model also implies the possibility of constructing a common model of gastrulation among chordate species.

  10. [Aquatic animals of medical importance in Brazil].

    PubMed

    Haddad Junior, Vidal

    2003-01-01

    The injuries caused by venomous and poisonous aquatic animals may provoke important morbidity in the victim. The cnidarians (jellyfishes, especially cubomedusas and Portuguese-Man-of-War) caused nearly 25% of 236 accidents by marine animals, while sea urchins were responsible for about 50% and catfish, stingrays and scorpionfish nearly 25%). In freshwater, stingrays and catfish cause injuries with a very similar mechanism to the poisoning and the effects of the toxins of marine species. In a series of about 200 injuries observed among freshwater fishermen, nearly 40% were caused by freshwater catfish, 5% freshwater stingrays and 55% by traumatogenic fish, such as piranhas and traíras. The author presents the aquatic animals that cause injuries to humans in Brazil, the clinical aspects of the envenoming and the first measures for the control of the severe pain observed mainly in the accidents caused by cnidarians and venomous fishes.

  11. [Aquatic animals of medical importance in Brazil].

    PubMed

    Haddad Junior, Vidal

    2003-01-01

    The injuries caused by venomous and poisonous aquatic animals may provoke important morbidity in the victim. The cnidarians (jellyfishes, especially cubomedusas and Portuguese-Man-of-War) caused nearly 25% of 236 accidents by marine animals, while sea urchins were responsible for about 50% and catfish, stingrays and scorpionfish nearly 25%). In freshwater, stingrays and catfish cause injuries with a very similar mechanism to the poisoning and the effects of the toxins of marine species. In a series of about 200 injuries observed among freshwater fishermen, nearly 40% were caused by freshwater catfish, 5% freshwater stingrays and 55% by traumatogenic fish, such as piranhas and traíras. The author presents the aquatic animals that cause injuries to humans in Brazil, the clinical aspects of the envenoming and the first measures for the control of the severe pain observed mainly in the accidents caused by cnidarians and venomous fishes. PMID:14576874

  12. Characterization factors for thermal pollution in freshwater aquatic environments.

    PubMed

    Verones, Francesca; Hanafiah, Marlia Mohd; Pfister, Stephan; Huijbregts, Mark A J; Pelletier, Gregory J; Koehler, Annette

    2010-12-15

    To date the impact of thermal emissions has not been addressed in life cycle assessment despite the narrow thermal tolerance of most aquatic species. A method to derive characterization factors for the impact of cooling water discharges on aquatic ecosystems was developed which uses space and time explicit integration of fate and effects of water temperature changes. The fate factor is calculated with a 1-dimensional steady-state model and reflects the residence time of heat emissions in the river. The effect factor specifies the loss of species diversity per unit of temperature increase and is based on a species sensitivity distribution of temperature tolerance intervals for various aquatic species. As an example, time explicit characterization factors were calculated for the cooling water discharge of a nuclear power plant in Switzerland, quantifying the impact on aquatic ecosystems of the rivers Aare and Rhine. The relative importance of the impact of these cooling water discharges was compared with other impacts in life cycle assessment. We found that thermal emissions are relevant for aquatic ecosystems compared to other stressors, such as chemicals and nutrients. For the case of nuclear electricity investigated, thermal emissions contribute between 3% and over 90% to Ecosystem Quality damage.

  13. Infertility in male aquatic invertebrates: a review.

    PubMed

    Lewis, Ceri; Ford, Alex T

    2012-09-15

    As a result of endocrine disruptor studies, there are numerous examples of male related reproductive abnormalities observed in vertebrates. Contrastingly, within the invertebrates there have been considerably less examples both from laboratory and field investigations. This has in part been due to a focus of female related endpoints, inadequate biomarkers and the low number of studies. Whether contaminant induced male infertility is an issue within aquatic invertebrates and their wider communities therefore remains largely unknown and represents a key knowledge gap in our understanding of pollutant impacts in aquatic wildlife. This paper reviews the current knowledge regarding pollutants impacting male infertility across several aquatic invertebrate phyla; which biomarkers are currently being used and where the science needs to be expanded. The limited studies conducted so far have revealed reductions in sperm numbers, examples of poor fertilisation success, DNA damage to spermatozoa and inhibition of sperm motility that can be induced by a range of environmental contaminants. This limited data is mainly comprised from laboratory studies with only a few studies of sperm toxicity in natural populations. Clearly, there is a need for further studies in this area, to include both laboratory and field studies from clean and reference sites, with a focus on broadcast spawners and those with direct fertilisation. Biomarkers developed for measuring sperm quantity and quality in vertebrates are easily transferable to invertebrates but require optimisation for particular species. We discuss how sperm tracking and techniques for measuring DNA strand breaks and sperm viability have been successfully transferred from human infertility clinics to aquatic invertebrate ecotoxicology. Linking sperm toxicity and male infertility effects to higher level impacts on the reproductive biology and dynamics of populations requires a much greater understanding of fertilisation dynamics and

  14. Protection Goals for Aquatic Plants

    EPA Science Inventory

    Someone once said plants are the ugly stepchildren of the toxicological world. This was not out of lack of respect for plants, but rather reflected the common assumption that aquatic plants were less sensitive than aquatic fauna to chemicals. We now know this is not a valid gener...

  15. Tool use by aquatic animals

    PubMed Central

    Mann, Janet; Patterson, Eric M.

    2013-01-01

    Tool-use research has focused primarily on land-based animals, with less consideration given to aquatic animals and the environmental challenges and conditions they face. Here, we review aquatic tool use and examine the contributing ecological, physiological, cognitive and social factors. Tool use among aquatic animals is rare but taxonomically diverse, occurring in fish, cephalopods, mammals, crabs, urchins and possibly gastropods. While additional research is required, the scarcity of tool use can likely be attributable to the characteristics of aquatic habitats, which are generally not conducive to tool use. Nonetheless, studying tool use by aquatic animals provides insights into the conditions that promote and inhibit tool-use behaviour across biomes. Like land-based tool users, aquatic animals tend to find tools on the substrate and use tools during foraging. However, unlike on land, tool users in water often use other animals (and their products) and water itself as a tool. Among sea otters and dolphins, the two aquatic tool users studied in greatest detail, some individuals specialize in tool use, which is vertically socially transmitted possibly because of their long dependency periods. In all, the contrasts between aquatic- and land-based tool users enlighten our understanding of the adaptive value of tool-use behaviour. PMID:24101631

  16. Forestry practices and aquatic biodiversity: Fish

    USGS Publications Warehouse

    Gresswell, Robert E.

    2005-01-01

    In the Pacific Northwest, fish communities are found in a diverse array of aquatic habitats ranging from the large coastal rivers of the temperate rainforests, to the fragmented and sometimes ephemeral streams of the xeric interior basins, and high-elevation streams and lakes in the mountainous areas (Rieman et al. 2003). Only high-elevation lakes and streams isolated above barriers to fish passage remained historically devoid of fish because they were never invaded following Pleistocene glaciation (Smith 1981). Despite this widespread distribution and once great population abundances, taxonomic diversity of fishes in these forested systems is naturally lower than in aquatic habitats in the eastern U.S. (Reeves, Bisson, and Dambacher 1998). Interactions among factors that influence species richness in aquatic systems (e.g., basin size, long-term stability of habitat, and barriers to colonization; Smith 1981) continue to influence the occurrence and persistence of fishes in these systems today. Consequently, the larger low-elevation rivers and estuaries support the greatest variety of fish species. In the high-elevation tributary streams, fish communities are less complex because these aquatic systems were less climatically and geologically stable, and fish populations were smaller and more prone to local extirpation. Furthermore, barriers to fish passage inhibited dispersal and colonization (Smith 1981). Streams in forested landscapes generally support salmon and trout, Oncorhynchus spp., whitefish Prosopium spp., sculpins Cottus spp., suckers Catostomus spp., and minnows (Cyprinidae), but in some of the colder streams, chars (e.g., Salvelinus confluentus and Salvelinus malma) and lampreys (Petromyzontidae)may also occur (Rieman et al. 2003).Although biodiversity defined in terms of fish species richness is low in the Pacific Northwest, intraspecific variability is high, and polytypic fish species are common in the diverse aquatic habitats of the region. For

  17. Forestry practices and aquatic biodiversity: Fish

    USGS Publications Warehouse

    Gresswell, Robert E.

    2005-01-01

    In the Pacific Northwest, fish communities are found in a diverse array of aquatic habitats ranging from the large coastal rivers of the temperate rainforests, to the fragmented and sometimes ephemeral streams of the xeric interior basins, and high-elevation streams and lakes in the mountainous areas (Rieman et al. 2003). Only high-elevation lakes and streams isolated above barriers to fish passage remained historically devoid of fish because they were never invaded following Pleistocene glaciation (Smith 1981). Despite this widespread distribution and once great population abundances, taxonomic diversity of fishes in these forested systems is naturally lower than in aquatic habitats in the eastern U.S. (Reeves, Bisson, and Dambacher 1998). Interactions among factors that influence species richness in aquatic systems (e.g., basin size, long-term stability of habitat, and barriers to colonization; Smith 1981) continue to influence the occurrence and persistence of fishes in these systems today. Consequently, the larger low-elevation rivers and estuaries support the greatest variety of fish species. In the high-elevation tributary streams, fish communities are less complex because these aquatic systems were less climatically and geologically stable, and fish populations were smaller and more prone to local extirpation. Furthermore, barriers to fish passage inhibited dispersal and colonization (Smith 1981). Streams in forested landscapes generally support salmon and trout, Oncorhynchus spp., whitefish Prosopium spp., sculpins Cottus spp., suckers Catostomus spp., and minnows (Cyprinidae), but in some of the colder streams, chars (e.g., Salvelinus confluentus and Salvelinus malma) and lampreys (Petromyzontidae)may also occur (Rieman et al. 2003).Although biodiversity defined in terms of fish species richness is low in the Pacific Northwest, intraspecific variability is high, and polytypic fish species are common in the diverse aquatic habitats of the region. For

  18. Aquatic environmental nanoparticles.

    PubMed

    Wigginton, Nicholas S; Haus, Kelly L; Hochella, Michael F

    2007-12-01

    Researchers are now discovering that naturally occurring environmental nanoparticles can play a key role in important chemical characteristics and the overall quality of natural and engineered waters. The detection of nanoparticles in virtually all water domains, including the oceans, surface waters, groundwater, atmospheric water, and even treated drinking water, demonstrates a distribution near ubiquity. Moreover, aquatic nanoparticles have the ability to influence environmental and engineered water chemistry and processes in a much different way than similar materials of larger sizes. This review covers recent advances made in identifying nanoparticles within water from a variety of sources, and advances in understanding their very interesting properties and reactivity that affect the chemical characteristics and behaviour of water. In the future, this science will be important in our vital, continuing efforts in water safety, treatment, and remediation.

  19. Evaluation of seven aquatic sampling methods for amphibians and other aquatic fauna

    USGS Publications Warehouse

    Gunzburger, M.S.

    2007-01-01

    To design effective and efficient research and monitoring programs researchers must have a thorough understanding of the capabilities and limitations of their sampling methods. Few direct comparative studies exist for aquatic sampling methods for amphibians. The objective of this study was to simultaneously employ seven aquatic sampling methods in 10 wetlands to compare amphibian species richness and number of individuals detected with each method. Four sampling methods allowed counts of individuals (metal dipnet, D-frame dipnet, box trap, crayfish trap), whereas the other three methods allowed detection of species (visual encounter, aural, and froglogger). Amphibian species richness was greatest with froglogger, box trap, and aural samples. For anuran species, the sampling methods by which each life stage was detected was related to relative length of larval and breeding periods and tadpole size. Detection probability of amphibians varied across sampling methods. Box trap sampling resulted in the most precise amphibian count, but the precision of all four count-based methods was low (coefficient of variation > 145 for all methods). The efficacy of the four count sampling methods at sampling fish and aquatic invertebrates was also analyzed because these predatory taxa are known to be important predictors of amphibian habitat distribution. Species richness and counts were similar for fish with the four methods, whereas invertebrate species richness and counts were greatest in box traps. An effective wetland amphibian monitoring program in the southeastern United States should include multiple sampling methods to obtain the most accurate assessment of species community composition at each site. The combined use of frogloggers, crayfish traps, and dipnets may be the most efficient and effective amphibian monitoring protocol. ?? 2007 Brill Academic Publishers.

  20. Insar of Aquatic Bodies

    NASA Astrophysics Data System (ADS)

    Tarikhi, P.

    2012-07-01

    Radar remote sensing is a new earth observation technology with promising results and future. InSAR is a sophisticated radar remote sensing technique for combining synthetic aperture radar (SAR) single look complex images to form interferogram and utilizing its phase contribution to land topography, surface movement and target velocity. In recent years considerable applications of Interferometric SAR technique have been developed. It is an established technique for precise assessment of land surface movements, and generating high quality digital elevation models (DEM) from space-borne and airborne data. InSAR is able to produce DEMs with the precision of a couple of ten meters whereas its movement map results have sub-centimeter precision. The technique has many applications in the context of earth sciences such as topographic mapping, environmental modelling, rainfall-runoff studies, landslide hazard zonation, and seismic source modelling. Nevertheless new developments are taking place in the application of InSAR for aquatic bodies. We have observed that using SAR Interferometry technique for aquatic bodies with the maximum temporal baseline of 16 seconds for image pairs shows considerable results enabling us to determine the direction of sea surface motion in a large area, estimate the sea surface fluctuations in the direction of sensor line-of-the-sight, detect wave pattern and the sea surface disturbance and whether the water motion is bulk and smooth or otherwise. This paper presents our experience and achievements on this new topic through discussing the facts and conditions for the use of InSAR technique. The method has been examined for Haiti, Dominican Republic, Western Chile and Western Turkey coast areas and inland lakes however ground truth data is needed for final verification. This technique scheduled to be applied in some other sites for which the proper data is available.

  1. Efficacy of trap modifications for increasing capture rates of aquatic snakes in floating aquatic funnel traps

    USGS Publications Warehouse

    Halstead, Brian J.; Wylie, Glenn D.; Casazza, Michael L.

    2013-01-01

    Increasing detection and capture probabilities of rare or elusive herpetofauna of conservation concern is important to inform the scientific basis for their management and recovery. The Giant Gartersnake (Thamnophis gigas) is an example of a secretive, wary, and generally difficult-to-sample species about which little is known regarding its patterns of occurrence and demography. We therefore evaluated modifications to existing traps to increase the detection and capture probabilities of the Giant Gartersnake to improve the precision with which occurrence, abundance, survival, and other demographic parameters are estimated. We found that adding a one-way valve constructed of cable ties to the small funnel opening of traps and adding hardware cloth extensions to the wide end of funnels increased capture rates of the Giant Gartersnake by 5.55 times (95% credible interval = 2.45–10.51) relative to unmodified traps. The effectiveness of these modifications was insensitive to the aquatic habitat type in which they were deployed. The snout-vent length of the smallest and largest captured snakes did not vary among trap modifications. These trap modifications are expected to increase detection and capture probabilities of the Giant Gartersnake, and show promise for increasing the precision with which demographic parameters can be estimated for this species. We anticipate that the trap modifications found effective in this study will be applicable to a variety of aquatic and semi-aquatic reptiles and amphibians and improve conservation efforts for these species.

  2. Aquatic Plant Management Program current status and seasonal workplan

    SciTech Connect

    Burns, E.R.; Bates, A.L.; Webb, D.H.

    1993-07-01

    The objective of the TVA Aquatic Plant Management Program is to support in an environmentally and economically responsible manner, the balanced multiple uses of the water resource of the Tennessee Valley. This is accomplished by following an integrated approach to prevent introduction and spread of noxious species, documenting occurrence and spread of existing species, and suppressing or eliminating problems in designated high use areas. It is not the TVA objective, nor is it biologically feasible and prudent to eliminate all aquatic vegetation. Aerial photography, helicopter reconnaissance, and field surveys are used to assess distributions and abundance of various aquatic macrophytes. Water level fluctuations are supplemented by herbicide applications to control undesirable vegetation. Investigations are conducted to evaluate water level fluctuation schemes, as well as biological, mechanical, and alternative chemical control techniques which offer potential for more environmentally compatible and cost-effective management operations.

  3. Freshwater ecosystems and aquatic insects: a paradox in biological invasions.

    PubMed

    Fenoglio, Stefano; Bonada, Núria; Guareschi, Simone; López-Rodríguez, Manuel J; Millán, Andrés; Tierno de Figueroa, J Manuel

    2016-04-01

    Biological invasions have increased significantly in response to global change and constitute one of the major causes of biodiversity loss. Insects make up a large fraction of invasive species, in general, and freshwaters are among the most invaded ecosystems on our planet. However, even though aquatic insects dominate most inland waters, have unparalleled taxonomic diversity and occupy nearly all trophic niches, there are almost no invasive insects in freshwaters. We present some hypotheses regarding why aquatic insects are not common among aquatic invasive organisms, suggesting that it may be the result of a suite of biological, ecological and anthropogenic factors. Such specific knowledge introduces a paradox in the current scientific discussion on invasive species; therefore, a more in-depth understanding could be an invaluable aid to disentangling how and why biological invasions occur.

  4. Freshwater ecosystems and aquatic insects: a paradox in biological invasions.

    PubMed

    Fenoglio, Stefano; Bonada, Núria; Guareschi, Simone; López-Rodríguez, Manuel J; Millán, Andrés; Tierno de Figueroa, J Manuel

    2016-04-01

    Biological invasions have increased significantly in response to global change and constitute one of the major causes of biodiversity loss. Insects make up a large fraction of invasive species, in general, and freshwaters are among the most invaded ecosystems on our planet. However, even though aquatic insects dominate most inland waters, have unparalleled taxonomic diversity and occupy nearly all trophic niches, there are almost no invasive insects in freshwaters. We present some hypotheses regarding why aquatic insects are not common among aquatic invasive organisms, suggesting that it may be the result of a suite of biological, ecological and anthropogenic factors. Such specific knowledge introduces a paradox in the current scientific discussion on invasive species; therefore, a more in-depth understanding could be an invaluable aid to disentangling how and why biological invasions occur. PMID:27072403

  5. Aquatic adventitious root development in partially and completely submerged wetland plants Cotula coronopifolia and Meionectes brownii

    PubMed Central

    Rich, Sarah Meghan; Ludwig, Martha; Colmer, Timothy David

    2012-01-01

    Background and Aims A common response of wetland plants to flooding is the formation of aquatic adventitious roots. Observations of aquatic root growth are widespread; however, controlled studies of aquatic roots of terrestrial herbaceous species are scarce. Submergence tolerance and aquatic root growth and physiology were evaluated in two herbaceous, perennial wetland species Cotula coronopifolia and Meionectes brownii. Methods Plants were raised in large pots with ‘sediment’ roots in nutrient solution and then placed into individual tanks and shoots were left in air or submerged (completely or partially). The effects on growth of aquatic root removal, and of light availability to submerged plant organs, were evaluated. Responses of aquatic root porosity, chlorophyll and underwater photosynthesis, were studied. Key Results Both species tolerated 4 weeks of complete or partial submergence. Extensive, photosynthetically active, aquatic adventitious roots grew from submerged stems and contributed up to 90 % of the total root dry mass. When aquatic roots were pruned, completely submerged plants grew less and had lower stem and leaf chlorophyll a, as compared with controls with intact roots. Roots exposed to the lowest PAR (daily mean 4·7 ± 2·4 µmol m−2 s−1) under water contained less chlorophyll, but there was no difference in aquatic root biomass after 4 weeks, regardless of light availability in the water column (high PAR was available to all emergent shoots). Conclusions Both M. brownii and C. coronopifolia responded to submergence with growth of aquatic adventitious roots, which essentially replaced the existing sediment root system. These aquatic roots contained chlorophyll and were photosynthetically active. Removal of aquatic roots had negative effects on plant growth during partial and complete submergence. PMID:22419759

  6. A pre-vegetated mat technique for the restoration of submersed aquatic vegetation

    USGS Publications Warehouse

    Boustany, R.G.

    2003-01-01

    Intro paragraph: Communities of submersed aquatic vegetation (SAV) provide critical habitat for wintering waterfowl and many commercially important fish species. Submersed aquatic vegetation also helps minimize storm damage by reducing wave action and stabilizing sediments, and they improve water quality by sequestering nutrients and contaminants (Zieman and Zieman 1989).

  7. An unusual case of seed dispersal in an invasive aquatic; yellow flag iris (Iris pseudacorus)

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Understanding reproductive mode of invasive plants can help managers plan more efficacious control. Invasive aquatics typically reproduce primarily through vegetative means. Yellow flag iris is an invasive plant species often growing as an emergent aquatic. There have been contradictory reports of i...

  8. Environmental enrichment for aquatic animals.

    PubMed

    Corcoran, Mike

    2015-05-01

    Aquatic animals are the most popular pets in the United States based on the number of owned pets. They are popular display animals and are increasingly used in research settings. Enrichment of captive animals is an important element of zoo and laboratory medicine. The importance of enrichment for aquatic animals has been slower in implementation. For a long time, there was debate over whether or not fish were able to experience pain or form long-term memories. As that debate has reduced and the consciousness of more aquatic animals is accepted, the need to discuss enrichment for these animals has increased.

  9. Aquatic toxicology: fact or fiction?

    PubMed Central

    Macek, K J

    1980-01-01

    A brief history of the development of the field of aquatic toxicology is provided. In order to provide a perspective on the state-of-the-art in aquatic toxicology relative to classical toxicology, the two fields are compared from the standpoint of the type of scientist practicing each field, the respective objectives of each, the forces which drive the activity in each field, and the major advantages and disadvantages accruing to the practitioner of aquatic toxicology as a result of the differences in objectives and driving forces. PMID:6993200

  10. Aquatic Invertebrate Development Working Group

    NASA Technical Reports Server (NTRS)

    Meyers, D.

    1985-01-01

    Little definitive evidence exists to show that gravity plays a major role in embyrogenesis of aquatic invertebrates. Two reasons for this may be: (1) few studies have been done that emphasize the role of gravity; and (2) there simply may not be any gravity effect. The buoyant nature of the aquatic environment could have obscured any evolutionary effect of gravity. The small size of most eggs and their apparent lack of orientation suggests reduced gravitational influence. Therefore, it is recommended that the term development, as applied to aquatic invertebrates, be loosely defined to encompass behavioral and morphological parameters for which baseline data already exist.

  11. Solar aquatic treatment of septage

    SciTech Connect

    Spencer, R.

    1990-05-01

    This article describes a pilot project for solar aquatic treatment of septage. The system is housed in a 42 ft by 128 ft greenhouse and consists of four parallel trains of aerated transparent tanks and constructed marshes. Each treatment tank is seeded with a mixture of bacteria, snails, algae and aquatic and woody plants that remove nitrates and pollutants such as heavy metals. Critics of solar aquatic systems point out that the heavy metals and other pollutants then become a solid waste disposal problem. Among the solutions offered are the use of hyperaccumulators of metals that produce ore-grade concentrations that can be efficiently recycled.

  12. Aquatic phytoremendiation: Algae and aquatic plants for removal of toxic elements

    SciTech Connect

    Benemann, J.R.

    1996-12-31

    A study to test several species of plants for heavy metal bioremoval is very briefly described. Adsorption isotherms were determined for cadmium, zinc, lead, nickel, and copper by measuring the amounts adsorbed by the biomass over a range of residual metal concentrations. Numerical results presented include adsorption characteristics of aquatic plants at pH 5 and specific adsorption of cadmium onto various biomass. The two best species were Phormidium, a blue-green alga, and Myriophyllum spicatum, water milfoil. The maximum metal ion absorbed the the minimal residual metal concentrations achieved allow estimation of the amount of biomass required to achieve a desired treatment level.

  13. New Midwestern state records of aquatic Hemiptera (Corixidae: Notonectidae)

    USGS Publications Warehouse

    Chordas, Stephen W.; Chapman, Eric G.; Hudson, Patrick L.; Chriscinske, Margret A.; Stewart, Richard L.

    2002-01-01

    Recent aquatic Hemiptera collections have yielded 15 new state records distributed among four midwestern States. These records include two species of water boatmen (Palmacorixa gillettei and Sigara mathesoni) new for Indiana, four water boatmen species (Cenocorixa utahensis, Corisella inscripta, Hesperocorixa laevigata, S. decorata), including one genus (Cenocorixa) new for Michigan, four water boatmen species (Corisella edulis, Trichocorixa macroceps, S. decoratella, S. mathesoni) and one backswimmer species (Notonecta indica) new for Ohio, and four water boatmen species (H. kennicotti, H. semilucida, S. compressoidea, S. variabilis) new for Pennsylvania.

  14. Differentiating aquatic plant communities in a eutrophic river using hyperspectral and multispectral remote sensing

    USGS Publications Warehouse

    Tian, Y.Q.; Yu, Q.; Zimmerman, M.J.; Flint, S.; Waldron, M.C.

    2010-01-01

    This study evaluates the efficacy of remote sensing technology to monitor species composition, areal extent and density of aquatic plants (macrophytes and filamentous algae) in impoundments where their presence may violate water-quality standards. Multispectral satellite (IKONOS) images and more than 500 in situ hyperspectral samples were acquired to map aquatic plant distributions. By analyzing field measurements, we created a library of hyperspectral signatures for a variety of aquatic plant species, associations and densities. We also used three vegetation indices. Normalized Difference Vegetation Index (NDVI), near-infrared (NIR)-Green Angle Index (NGAI) and normalized water absorption depth (DH), at wavelengths 554, 680, 820 and 977 nm to differentiate among aquatic plant species composition, areal density and thickness in cases where hyperspectral analysis yielded potentially ambiguous interpretations. We compared the NDVI derived from IKONOS imagery with the in situ, hyperspectral-derived NDVI. The IKONOS-based images were also compared to data obtained through routine visual observations. Our results confirmed that aquatic species composition alters spectral signatures and affects the accuracy of remote sensing of aquatic plant density. The results also demonstrated that the NGAI has apparent advantages in estimating density over the NDVI and the DH. In the feature space of the three indices, 3D scatter plot analysis revealed that hyperspectral data can differentiate several aquatic plant associations. High-resolution multispectral imagery provided useful information to distinguish among biophysical aquatic plant characteristics. Classification analysis indicated that using satellite imagery to assess Lemna coverage yielded an overall agreement of 79% with visual observations and >90% agreement for the densest aquatic plant coverages. Interpretation of biophysical parameters derived from high-resolution satellite or airborne imagery should prove to be a

  15. Bioconcentration, bioaccumulation, and metabolism of pesticides in aquatic organisms.

    PubMed

    Katagi, Toshiyuki

    2010-01-01

    detoxification and bioactivation. Hydrophobic pesticides that are expected to be highly stored in tissues would not be bioconcentrated if susceptible to biotic transformation by aquatic organisms to more rapidly metabolized to hydrophilic entities are generally less toxic. By analogy, pesticides that are metabolized to similar entities by aquatic species surely are les ecotoxicologically significant. One feature of fish and other aquatic species that makes them more relevant as targets of environmental studies and of regulation is that they may not only become contaminated by pesticides or other chemicals, but that they constitute and important part of the human diet. In this chapter, we provide an overview of the enzymes that are capable of metabolizing or otherwise assisting in the removal of xenobiotics from aquatic species. Many studies have been performed on the enzymes that are responsible for metabolizing xenobiotics. In addition to the use of conventional biochemical methods, such studies on enzymes are increasingly being conducted using immunochemical methods and amino acid or gene sequences analysis. Such studies have been performed in algae, in some aquatic macrophytes, and in bivalva, but less information is available for other aquatic species such as crustacea, annelids, aquatic insecta, and other species. Although their catabolizing activity is often lower than in mammals, oxidases, especially cytochrome P450 enzymes, play a central role in transforming pesticides in aquatic organisms. Primary metabolites, formed from such initial enzymatic action, are further conjugated with natural components such as carbohydrates, and this aids removal form the organisms. The pesticides that are susceptible to abiotic hydrolysis are generally also biotically degraded by various esterases to from hydrophilic conjugates. Reductive transformation is the main metabolic pathway for organochlorine pesticides, but less information on reductive enzymology processes is available. The

  16. Children's Aquatics: Managing the Risk.

    ERIC Educational Resources Information Center

    Langendorfer, Stephen; And Others

    1989-01-01

    This article identifies the major risks faced by young children in aquatic programs, outlines several methods for managing risk factors, and discusses the steps involved in implementing a risk-management system. (IAH)

  17. Correlations of life form, pollination mode and sexual system in aquatic angiosperms.

    PubMed

    Du, Zhi-Yuan; Wang, Qing-Feng

    2014-01-01

    Aquatic plants are phylogenetically well dispersed across the angiosperms. Reproductive and other life-history traits of aquatic angiosperms are closely associated with specific growth forms. Hydrophilous pollination exhibits notable examples of convergent evolution in angiosperm reproductive structures, and hydrophiles exhibit great diversity in sexual system. In this study, we reconstructed ancestral characters of aquatic lineages based on the phylogeny of aquatic angiosperms. Our aim is to find the correlations of life form, pollination mode and sexual system in aquatic angiosperms. Hydrophily is the adaptive evolution of completely submersed angiosperms to aquatic habitats. Hydroautogamy and maleflower-ephydrophily are the transitional stages from anemophily and entomophily to hydrophily. True hydrophily occurs in 18 submersed angiosperm genera, which is associated with an unusually high incidence of unisexual flowers. All marine angiosperms are submersed, hydrophilous species. This study would help us understand the evolution of hydrophilous pollination and its correlations with life form and sexual system.

  18. Correlations of Life Form, Pollination Mode and Sexual System in Aquatic Angiosperms

    PubMed Central

    Du, Zhi-Yuan; Wang, Qing-Feng

    2014-01-01

    Aquatic plants are phylogenetically well dispersed across the angiosperms. Reproductive and other life-history traits of aquatic angiosperms are closely associated with specific growth forms. Hydrophilous pollination exhibits notable examples of convergent evolution in angiosperm reproductive structures, and hydrophiles exhibit great diversity in sexual system. In this study, we reconstructed ancestral characters of aquatic lineages based on the phylogeny of aquatic angiosperms. Our aim is to find the correlations of life form, pollination mode and sexual system in aquatic angiosperms. Hydrophily is the adaptive evolution of completely submersed angiosperms to aquatic habitats. Hydroautogamy and maleflower-ephydrophily are the transitional stages from anemophily and entomophily to hydrophily. True hydrophily occurs in 18 submersed angiosperm genera, which is associated with an unusually high incidence of unisexual flowers. All marine angiosperms are submersed, hydrophilous species. This study would help us understand the evolution of hydrophilous pollination and its correlations with life form and sexual system. PMID:25525810

  19. Aquatic Plants Aid Sewage Filter

    NASA Technical Reports Server (NTRS)

    Wolverton, B. C.

    1985-01-01

    Method of wastewater treatment combines micro-organisms and aquatic plant roots in filter bed. Treatment occurs as liquid flows up through system. Micro-organisms, attached themselves to rocky base material of filter, act in several steps to decompose organic matter in wastewater. Vascular aquatic plants (typically, reeds, rushes, cattails, or water hyacinths) absorb nitrogen, phosphorus, other nutrients, and heavy metals from water through finely divided roots.

  20. [Development characteristics of aquatic plants in a constructed wetland for treating urban drinking water source at its initial operation stage].

    PubMed

    Zheng, Jun; Ma, Xin-Tang; Zhou, Lan; Zhou, Qing-Yuan; Wang, Zhong-Qiong; Wang, Wei-Dong; Yin, Cheng-Qing

    2011-08-01

    The development characteristics and improvement measures of aquatic plants were studied in Shijiuyang Constructed Wetland (SCW) at its initial operation stage. SCW was a large-scale wetland aiming to help relieve the source water pollution in Jiaxing City. A checklist of vascular plants in SCW was built, and species composition, life forms, biomass and association distributions were examined. Our objectives were to examine the diversity and community structure of aquatic plants in SCW at its initial operation stage, and to find out the possible hydrophyte improvement measures. The survey results showed that there were 49 vascular plant species belonging to 41 genera, 25 families in SCW, which greatly exceeded the artificially transplanted 13 species. The life forms of present aquatic plants in SCW were dominated by hygrophilous plants (20 species) and emerged plants (17 species), which accounted for 75.5% of the total number of aquatic plants. The aquatic plants transplanted artificially were dominated by emerged plants (accounted for 69.2%), while those naturally developed were predominated by hygrophilous plants (accounted for 47.2%). The horizontal distribution of aquatic plant community in SCW was mixed in the form of mosaics, which made up typical association complex. Except association Aeschynomene indica L., the dominant species of other associations were all those transplanted artificially. The naturally grown species scattered throughout the SCW and only occupied a small percentage. A marked difference was detected on the species and species richness of aquatic plants in different regions of SCW. Biomass of aquatic plant associations in SCW was 167.7 t. SCW has shown a trend of succession heading for quick increase of plant diversity at the primary operation stage. This trend provides a good material base for the future stable community of aquatic plants in SCW. According to the current status of aquatic plants, some suggestions were put forward on the

  1. Science: Aquatic Toxicology Matures, Gains Importance.

    ERIC Educational Resources Information Center

    Dagani, Ron

    1980-01-01

    Reviews recent advances in aquatic toxicology, whose major goal is to protect diverse aquatic organisms and whole ecological communities from the dire effects of man-made chemicals. Current legislation is reviewed. Differences in mammalian and aquatic toxicology are listed, and examples of research in aquatic toxicology are discussed. (CS)

  2. Montsechia, an ancient aquatic angiosperm.

    PubMed

    Gomez, Bernard; Daviero-Gomez, Véronique; Coiffard, Clément; Martín-Closas, Carles; Dilcher, David L

    2015-09-01

    The early diversification of angiosperms in diverse ecological niches is poorly understood. Some have proposed an origin in a darkened forest habitat and others an open aquatic or near aquatic habitat. The research presented here centers on Montsechia vidalii, first recovered from lithographic limestone deposits in the Pyrenees of Spain more than 100 y ago. This fossil material has been poorly understood and misinterpreted in the past. Now, based upon the study of more than 1,000 carefully prepared specimens, a detailed analysis of Montsechia is presented. The morphology and anatomy of the plant, including aspects of its reproduction, suggest that Montsechia is sister to Ceratophyllum (whenever cladistic analyses are made with or without a backbone). Montsechia was an aquatic angiosperm living and reproducing below the surface of the water, similar to Ceratophyllum. Montsechia is Barremian in age, raising questions about the very early divergence of the Ceratophyllum clade compared with its position as sister to eudicots in many cladistic analyses. Lower Cretaceous aquatic angiosperms, such as Archaefructus and Montsechia, open the possibility that aquatic plants were locally common at a very early stage of angiosperm evolution and that aquatic habitats may have played a major role in the diversification of some early angiosperm lineages. PMID:26283347

  3. Montsechia, an ancient aquatic angiosperm

    PubMed Central

    Gomez, Bernard; Daviero-Gomez, Véronique; Coiffard, Clément; Martín-Closas, Carles; Dilcher, David L.

    2015-01-01

    The early diversification of angiosperms in diverse ecological niches is poorly understood. Some have proposed an origin in a darkened forest habitat and others an open aquatic or near aquatic habitat. The research presented here centers on Montsechia vidalii, first recovered from lithographic limestone deposits in the Pyrenees of Spain more than 100 y ago. This fossil material has been poorly understood and misinterpreted in the past. Now, based upon the study of more than 1,000 carefully prepared specimens, a detailed analysis of Montsechia is presented. The morphology and anatomy of the plant, including aspects of its reproduction, suggest that Montsechia is sister to Ceratophyllum (whenever cladistic analyses are made with or without a backbone). Montsechia was an aquatic angiosperm living and reproducing below the surface of the water, similar to Ceratophyllum. Montsechia is Barremian in age, raising questions about the very early divergence of the Ceratophyllum clade compared with its position as sister to eudicots in many cladistic analyses. Lower Cretaceous aquatic angiosperms, such as Archaefructus and Montsechia, open the possibility that aquatic plants were locally common at a very early stage of angiosperm evolution and that aquatic habitats may have played a major role in the diversification of some early angiosperm lineages. PMID:26283347

  4. Marine invasions by non-sea snakes, with thoughts on terrestrial-aquatic-marine transitions.

    PubMed

    Murphy, John C

    2012-08-01

    Few species of snakes show extensive adaptations to aquatic environments and even fewer exploit the oceans. A survey of morphology, lifestyles, and habitats of 2552 alethenophidian snakes revealed 362 (14%) that use aquatic environments, are semi-aquatic, or aquatic; about 70 (2.7%) of these are sea snakes (Hydrophiinae and Laticaudinae). The ancient and aquatic family Acrochordidae contains three extant species, all of which have populations inhabiting brackish or marine environments, as well as freshwater. The Homalopsidae have the most ecologically diverse representatives in coastal habitats. Other families containing species exploiting saline waters with populations in freshwater environments include: the Dipsadidae of the western hemisphere, the cosmopolitan Natricidae, the African Grayinae, and probably a few Colubridae. Species with aquatic and semi-aquatic lifestyles are compared with more terrestrial (fossorial, cryptozoic, and arboreal) species for morphological traits and life histories that are convergent with those found in sea snakes; this may provide clues to the evolution of marine snakes and increase our understanding of snake diversity.

  5. Aquatic insect community of lake, Phulbari anua in Cachar, Assam.

    PubMed

    Gupta, Susmita; Narzary, Rupali

    2013-05-01

    An investigation on the water quality and aquatic insect community of an oxbow lake (Phulbari anua) of south Assam, North-East India was carried out during February to April, 2010. Aquatic insect community of the oxbow lake was represented by 9 species belonging to 9 families and 4 orders during the study period. Order Ephemeroptera and Hemiptera were found to be dominant. Record of 5 species and 5 families from the order Hemiptera showed that this is the largest order in terms of aquatic insect diversity of the lake. Computation of dominance status of different species of aquatic insects of the lake based on Engelmann's Scale revealed that Anisops lundbladiana and Cloeon sp. were eudominant in the system. The Shannon- Weiner's Diversity Index (H') and Shannon evenness values (J') were found to range from 0.3-0.69 and 0.53 -0.97, respectively indicating perturbation of the system. Again in terms of physico-chemical properties of water the lake is in a satisfactory condition where all the parameters are well within the range of IS 10500. The DO values were found to range from 6.8 to 14.8 mgl(-1). Free CO2 fluctuated from 1 to 4.98 mgl(-1) and nitrate in water ranged from 0.4 to 2.1 mgl(-1). Margalef's water quality index values of most of the samplings also indicated clean water condition of the lake. Correlation coefficient analyses of the environmental variables, aquatic insect diversity and density of the lake revealed that aquatic insect diversity of the lake is mainly governed by dissolved oxygen, nitrate, and free carbon dioxide. PMID:24617147

  6. Aquatic insect community of lake, Phulbari anua in Cachar, Assam.

    PubMed

    Gupta, Susmita; Narzary, Rupali

    2013-05-01

    An investigation on the water quality and aquatic insect community of an oxbow lake (Phulbari anua) of south Assam, North-East India was carried out during February to April, 2010. Aquatic insect community of the oxbow lake was represented by 9 species belonging to 9 families and 4 orders during the study period. Order Ephemeroptera and Hemiptera were found to be dominant. Record of 5 species and 5 families from the order Hemiptera showed that this is the largest order in terms of aquatic insect diversity of the lake. Computation of dominance status of different species of aquatic insects of the lake based on Engelmann's Scale revealed that Anisops lundbladiana and Cloeon sp. were eudominant in the system. The Shannon- Weiner's Diversity Index (H') and Shannon evenness values (J') were found to range from 0.3-0.69 and 0.53 -0.97, respectively indicating perturbation of the system. Again in terms of physico-chemical properties of water the lake is in a satisfactory condition where all the parameters are well within the range of IS 10500. The DO values were found to range from 6.8 to 14.8 mgl(-1). Free CO2 fluctuated from 1 to 4.98 mgl(-1) and nitrate in water ranged from 0.4 to 2.1 mgl(-1). Margalef's water quality index values of most of the samplings also indicated clean water condition of the lake. Correlation coefficient analyses of the environmental variables, aquatic insect diversity and density of the lake revealed that aquatic insect diversity of the lake is mainly governed by dissolved oxygen, nitrate, and free carbon dioxide.

  7. Improving aquatic warbler population assessments by accounting for imperfect detection.

    PubMed

    Oppel, Steffen; Marczakiewicz, Piotr; Lachmann, Lars; Grzywaczewski, Grzegorz

    2014-01-01

    Monitoring programs designed to assess changes in population size over time need to account for imperfect detection and provide estimates of precision around annual abundance estimates. Especially for species dependent on conservation management, robust monitoring is essential to evaluate the effectiveness of management. Many bird species of temperate grasslands depend on specific conservation management to maintain suitable breeding habitat. One such species is the Aquatic Warbler (Acrocephalus paludicola), which breeds in open fen mires in Central Europe. Aquatic Warbler populations have so far been assessed using a complete survey that aims to enumerate all singing males over a large area. Because this approach provides no estimate of precision and does not account for observation error, detecting moderate population changes is challenging. From 2011 to 2013 we trialled a new line transect sampling monitoring design in the Biebrza valley, Poland, to estimate abundance of singing male Aquatic Warblers. We surveyed Aquatic Warblers repeatedly along 50 randomly placed 1-km transects, and used binomial mixture models to estimate abundances per transect. The repeated line transect sampling required 150 observer days, and thus less effort than the traditional 'full count' approach (175 observer days). Aquatic Warbler abundance was highest at intermediate water levels, and detection probability varied between years and was influenced by vegetation height. A power analysis indicated that our line transect sampling design had a power of 68% to detect a 20% population change over 10 years, whereas raw count data had a 9% power to detect the same trend. Thus, by accounting for imperfect detection we increased the power to detect population changes. We recommend to adopt the repeated line transect sampling approach for monitoring Aquatic Warblers in Poland and in other important breeding areas to monitor changes in population size and the effects of habitat management.

  8. A basin-specific aquatic food web biomagnification model for estimation of mercury target levels.

    PubMed

    Hope, Bruce

    2003-10-01

    In the Willamette River Basin (WRB, Oregon, USA), health advisories currently limit consumption of fish that have accumulated methylmercury (MeHg) to levels posing a potential health risk for humans. Under the Clean Water Act, these advisories create the requirement for a total maximum daily load (TMDL) for mercury in the WRB. A TMDL is a calculation of the maximum amount of a pollutant that a body of water can receive and still meet water-quality standards. Because MeHg is known to biomagnify in aquatic food webs, a basin-specific biomagnification factor can be used, given a protective fish tissue criterion, to estimate total mercury concentrations in surface waters required to lower advisory mercury concentrations currently in fish in the WRB. This paper presents an aquatic food web biomagnification model that simulates inorganic mercury (Hg(II)) and MeHg accumulation in fish tissue and estimates WRB-specific biomagnification factors for resident fish species of concern to stakeholders. Probabilistic (two-dimensional Monte Carlo) techniques propagate parameter variability and uncertainty throughout the model, providing decision makers with credible range information and increased flexibility in establishing a specific mercury target level. The model predicts the probability of tissue mercury concentrations in eight fish species within the range of concentrations measured in these species over 20 years of water-quality monitoring. Estimated mean biomagnification factor values range from 1.12 x 10(6) to 7.66 x 10(6) and are within the range of U.S. Environmental Protection Agency national values. Several WRB-specific mercury target levels are generated, which very by their probability of affording human health protection relative to the federal MeHg tissue criterion of 0.30 mg/kg. Establishing a specific numeric target level is, however, a public policy decision, and one that will require further discussions among WRB stakeholders. PMID:14552019

  9. Chesapeake Bay: an unprecedented decline in submerged aquatic vegetation

    SciTech Connect

    Orth, R.J.; Moore, K.A.

    1983-10-07

    Data on the distribution and abundance of submerged aquatic vegetation in Chesapeake Bay indicate a significant reduction in all species in all sections of the bay during the last 15 to 20 years. This decline is unprecedented in the bay's recent history. The reduction in one major species, Zostera marina, may be greater than the decline that occurred during the pandemic demise of the 1930's. 19 references, 2 figures.

  10. Aquatic organisms in acidic environments: a literature review

    SciTech Connect

    Eilers, J.M.; Lien, G.J.; Berg, R.G.

    1985-10-01

    Acid deposition has aroused concern about aquatic organisms in soft water lakes and streams, as the loss of indigenous species is commonly observed when pH decreases. This literature review was initiated to intensively examine the distribution of invertebrates with respect to pH, in order to define the tolerance limits of various species in acidified waters and predict how acidification would alter distributions.

  11. METHODOLOGY FOR THE EVALUATION OF CUMULATIVE EPISODIC EXPOSURE TO CHEMICAL STRESSORS IN AQUATIC RISK ASSESSMENT.

    EPA Science Inventory

    An ecological risk assessment method was developed to evaluate the magnitude, duration, and episodic nature of chemical stressors on aquatic communities. The percent of an ecosystem's species at risk from a designated chemical exposure scenario is generated. In effects assessment...

  12. A simple technique for trapping Siren lacertina, Amphiuma means, and other aquatic vertebrates

    USGS Publications Warehouse

    Johnson, S.A.; Barichivich, W.J.

    2004-01-01

    We describe a commercially-available funnel trap for sampling aquatic vertebrates. The traps can be used in heavily vegetated wetlands and can be set in water up to 60 cm deep without concern for drowning the animals. They were especially useful for capturing the aquatic salamanders Siren lacertina and Amphiuma means, which have been difficult to capture with traditional sampling methods. They also were effective for sampling small fishes, particularly centrarchids, and larval anurans. In total, 14 species of amphibians, nine species of aquatic reptiles, and at least 32 fish species were captured. The trap we describe differs significantly from traditional funnel traps (e.g., minnow traps) and holds great promise for studies of small, aquatic vertebrates, in particular Siren and Amphiuma species.

  13. From molecules to management: adopting DNA-based methods for monitoring biological invasions in aquatic environments

    EPA Science Inventory

    Recent technological advances have driven rapid development of DNA-based methods designed to facilitate detection and monitoring of invasive species in aquatic environments. These tools promise to significantly alleviate difficulties associated with traditional monitoring approac...

  14. The significance of the accumulation of cadmium by aquatic organisms

    SciTech Connect

    Taylor, D.

    1983-02-01

    Cadmium, by virtue of its toxicity, persistence, and bioaccumulation appears on the ''black list'' of all the international conventions aimed at protecting the aquatic environment from pollution. Although there is no doubt that cadmium is both persistent and toxic to aquatic life at relatively low concentrations, its bioaccumulation potential appears to have been somewhat exaggerated. Median concentration factors for both marine and freshwater organisms are less than 100 times and for vertebrate (fish) species concentration factors are less than 20 times. There is no evidence in the literature for biomagnification of cadmium and bioconcentration is only likely to be of significance in a restricted range of gastropod mollusks and some crustacea.

  15. Demonstration of free fatty acids in the integument of semi-aquatic and aquatic mammals.

    PubMed

    Meyer, Wilfried; Schmidt, Judith; Busche, Roger; Jacob, Ralf; Naim, Hassan Y

    2012-02-01

    The sensitive red fluorescence dye BODIPY® 665/676, and embedding in the water-soluble resin Technovit® 7100 were used to demonstrate free fatty acids in the epidermis of seven semi-aquatic and aquatic mammalian species with a sparse or dense hair coat. The staining generally marked lipid layers of varying thickness between the lamellae of the Stratum corneum, as found particularly in very densely haired species (otter), but also in rather sparsely haired animals (beaver, nutria), and especially in the seal. The very sparsely haired capybara contained no free fatty acids in the corneal layer system, but exhibited an accumulation of such substances in the vital epidermis. All haired species showed a strongly positive reaction staining of the sebaceous glands. In the hairless species, a distinct intracellular staining was restricted to cells of the thick vital epidermis in the hippopotamus, whereby in the Str. corneum positive intercellular reactions appeared. In the dolphin, on the contrary, positive intercellular reactions became visible in the vital epidermis, whereas in the Str. corneum the lipids concentrated in large longitudinal intracellular vesicles. PMID:21524787

  16. BIOMONITORING USING AQUATIC VEGETATION

    EPA Science Inventory

    This chapter provides an overview of the state-of-the-science as related to the phytoassessment techniques used in environmental biomonitoring and the hazard assessment process for chemicals. The emphasis is on freshwater angiosperms and bryophytes. Algal species, which are prese...

  17. [Policies, operational framework and guidelines of the Inter-American Committee on Aquatic Animal Health].

    PubMed

    Martínez, B; Tella, S Koloffon; McGladdery, S; Enríquez, R

    2008-04-01

    The Americas are home to a large population of aquatic animals, most of which are used in aquaculture. Production systems are diverse and are distributed over a wide and varied geographical area. This presents a challenge for the region, which must be able to meet food safety requirements for aquatic animals traded in the international market. The authors describe the creation of the Inter-American Committee on Aquatic Animal Health (IAC-AAH), as well as its composition, operation, objectives, the activities of the groups that form the Committee and the various activities conducted so far.

  18. The interaction between biology and the management of aquatic macrophytes

    USGS Publications Warehouse

    Nichols, S.A.

    1991-01-01

    'Management' refers to controlling nuisance aquatic species and to restoring or restructing aquatic plant communities. Producing stable, diverse, aquatic plant communities containing a high percentage of desirable species is a primary management goal. There are a variety of techniques including harvesting, herbicides, water-level fluctuation, sediment alteration, nutrient limitation, light alteration, and biological controls which can be used for managing macrophytes. These techniques are briefly reviewed along with discussions of biological considerations important to the efficacy of the technique and the environmental impacts of the technique. There is a growing interest in restoring and restructing aquatic plant communities. Techniques for community restoration are discussed as are emerging management technologies using growth regulators and bioengineering. New management technologies will probably be limited by costs and environmental impacts. In the near future, better macrophyte management will come through better planning and more effective use of present technology. The challenge is to make current planning and management techniques more effective through increased biological inputs. The potential for biological input ranges from subcellular biology to species biology, to community and ecosystem biology. Some information needs are identified. ?? 1991.

  19. Tritium in the aquatic environment

    SciTech Connect

    Blaylock, B.G.; Hoffman, F.O.; Frank, M.L.

    1986-02-01

    Tritium is of environmental importance because it is released from nuclear facilities in relatively large quantities and because it has a half life of 12.26 y. Most of the tritium released into the atmosphere eventually reaches the aqueous environment, where it is rapidly taken up by aquatic organisms. This paper reviews the current literature on tritium in the aquatic environment. Conclusions from the review, which covered studies of algae, aquatic macrophytes, invertebrates, fish, and the food chain, were that aquatic organisms incorporate tritium into their tissue-free water very rapidly and reach concentrations near those of the external medium. The rate at which tritium from tritiated water is incorporated into the organic matter of cells is slower than the rate of its incorporation into the tissue-free water. If organisms consume tritiated food, incorporation of tritium into the organic matter is faster, and a higher tritium concentration is reached than when the organisms are exposed to only tritiated water alone. Incorporation of tritium bound to molecules into the organic matter depends on the chemical form of the ''carrier'' molecule. No evidence was found that biomagnification of tritium occurs at higher trophic levels. Radiation doses from tritium releases to large populations of humans will most likely come from the consumption of contaminated water rather than contaminated aquatic food products.

  20. Review on environmental alterations propagating from aquatic to terrestrial ecosystems.

    PubMed

    Schulz, Ralf; Bundschuh, Mirco; Gergs, René; Brühl, Carsten A; Diehl, Dörte; Entling, Martin H; Fahse, Lorenz; Frör, Oliver; Jungkunst, Hermann F; Lorke, Andreas; Schäfer, Ralf B; Schaumann, Gabriele E; Schwenk, Klaus

    2015-12-15

    Terrestrial inputs into freshwater ecosystems are a classical field of environmental science. Resource fluxes (subsidy) from aquatic to terrestrial systems have been less studied, although they are of high ecological relevance particularly for the receiving ecosystem. These fluxes may, however, be impacted by anthropogenically driven alterations modifying structure and functioning of aquatic ecosystems. In this context, we reviewed the peer-reviewed literature for studies addressing the subsidy of terrestrial by aquatic ecosystems with special emphasis on the role that anthropogenic alterations play in this water-land coupling. Our analysis revealed a continuously increasing interest in the coupling of aquatic to terrestrial ecosystems between 1990 and 2014 (total: 661 studies), while the research domains focusing on abiotic (502 studies) and biotic (159 studies) processes are strongly separated. Approximately 35% (abiotic) and 25% (biotic) of the studies focused on the propagation of anthropogenic alterations from the aquatic to the terrestrial system. Among these studies, hydromorphological and hydrological alterations were predominantly assessed, whereas water pollution and invasive species were less frequently investigated. Less than 5% of these studies considered indirect effects in the terrestrial system e.g. via food web responses, as a result of anthropogenic alterations in aquatic ecosystems. Nonetheless, these very few publications indicate far-reaching consequences in the receiving terrestrial ecosystem. For example, bottom-up mediated responses via soil quality can cascade over plant communities up to the level of herbivorous arthropods, while top-down mediated responses via predatory spiders can cascade down to herbivorous arthropods and even plants. Overall, the current state of knowledge calls for an integrated assessment on how these interactions within terrestrial ecosystems are affected by propagation of aquatic ecosystem alterations. To fill

  1. Review on environmental alterations propagating from aquatic to terrestrial ecosystems.

    PubMed

    Schulz, Ralf; Bundschuh, Mirco; Gergs, René; Brühl, Carsten A; Diehl, Dörte; Entling, Martin H; Fahse, Lorenz; Frör, Oliver; Jungkunst, Hermann F; Lorke, Andreas; Schäfer, Ralf B; Schaumann, Gabriele E; Schwenk, Klaus

    2015-12-15

    Terrestrial inputs into freshwater ecosystems are a classical field of environmental science. Resource fluxes (subsidy) from aquatic to terrestrial systems have been less studied, although they are of high ecological relevance particularly for the receiving ecosystem. These fluxes may, however, be impacted by anthropogenically driven alterations modifying structure and functioning of aquatic ecosystems. In this context, we reviewed the peer-reviewed literature for studies addressing the subsidy of terrestrial by aquatic ecosystems with special emphasis on the role that anthropogenic alterations play in this water-land coupling. Our analysis revealed a continuously increasing interest in the coupling of aquatic to terrestrial ecosystems between 1990 and 2014 (total: 661 studies), while the research domains focusing on abiotic (502 studies) and biotic (159 studies) processes are strongly separated. Approximately 35% (abiotic) and 25% (biotic) of the studies focused on the propagation of anthropogenic alterations from the aquatic to the terrestrial system. Among these studies, hydromorphological and hydrological alterations were predominantly assessed, whereas water pollution and invasive species were less frequently investigated. Less than 5% of these studies considered indirect effects in the terrestrial system e.g. via food web responses, as a result of anthropogenic alterations in aquatic ecosystems. Nonetheless, these very few publications indicate far-reaching consequences in the receiving terrestrial ecosystem. For example, bottom-up mediated responses via soil quality can cascade over plant communities up to the level of herbivorous arthropods, while top-down mediated responses via predatory spiders can cascade down to herbivorous arthropods and even plants. Overall, the current state of knowledge calls for an integrated assessment on how these interactions within terrestrial ecosystems are affected by propagation of aquatic ecosystem alterations. To fill

  2. Aquatic plants for removal of mevinphos from the aquatic environment

    NASA Technical Reports Server (NTRS)

    Wolverton, B. C.

    1975-01-01

    Fragrant waterlily (Nymphaea odorata, Ait.), joint-grass (Paspalum distichum L.), and rush (Juncus repens, Michx.) were used to evaluate the effectiveness of vascular aquatic plants in removing the insecticide mevinphos (dimethyl-1-carbomethoxy-1propen-2-yl phosphate) from waters contaminated with this chemical. The emersed aquatic plants fragrant waterlily and joint-grass removed 87 and 93 ppm of mevinphos from water test systems in less than 2 weeks without apparent damage to the plants; whereas rush, a submersed plant, removed less insecticide than the water-soil controls. Water-soil control still contained toxic levels of this insecticide, as demonstrated by fish bioassay studies, after 35 days.

  3. Aquatic-surface microlayer contamination in Chesapeake Bay. Final report

    SciTech Connect

    Hardy, J.T.; Crecelius, B.A.; Antrim, L.D.; Kiesser, S.L.; Broadhurst, V.L.

    1987-08-01

    The boundary between the atmosphere and the aquatic environment is an important biological habitat and a collection point for pollutants. The eggs and larvae of many fish and shellfish species float on, or come in contact with, the water surface throughout their early development. The aquatic-surface microlayer serves as a concentration point for metal and organic contaminants that have low water solubility or are associated with floatable particles. Coal-fired power plants may release organic and metal contaminants into the environment that subsequently concentrate on the water surface. The objectives of this study were to (1) determine the present degree of aquatic surface microlayer pollution at selected sites in Chesapeake Bay, and (2) provide a preliminary evaluation of sources (including power plants) contributing to any observed contamination.

  4. Potential risk of biochar-amended soil to aquatic systems: an evaluation based on aquatic bioassays.

    PubMed

    Bastos, A C; Prodana, M; Abrantes, N; Keizer, J J; Soares, A M V M; Loureiro, S

    2014-11-01

    It is vital to address potential risks to aquatic ecosystems exposed to runoff and leachates from biochar-amended soils, before large scale applications can be considered. So far, there are no established approaches for such an assessment. This study used a battery of bioassays and representative aquatic organisms for assessing the acute toxicity of water-extractable fractions of biochar-amended soil, at reported application rates (80 t ha(-1)). Biochar-amended aqueous soil extracts contained cadmium (Cd), cobalt (Co), chromium (Cr), copper (Cu), manganese (Mn), zinc (Zn), nickel (Ni), lead (Pb), arsenic (As) and mercury (Hg) (Σmetals 96.3 µg l(-1)) as well as the 16 priority PAHs defined by the U.S. Environmental Protection Agency (Σ16PAHs 106 ng l(-1)) at contents in the range of current EU regulations for surface waters. Nevertheless, acute exposure to soil-biochar (SB) extracts resulted in species-specific effects and dose-response patterns. While the bioluminescent marine bacterium Vibrio fischeri was the most sensitive organism to aqueous SB extracts, there were no effects on the growth of the microalgae Pseudokirchneriella subcapitata. In contrast, up to 20 and 25% mobility impairment was obtained for the invertebrate Daphnia magna upon exposure to 50 and 100% SB extract concentrations (respectively). Results suggest that a battery of rapid and cost-effective aquatic bioassays that account for ecological representation can complement analytical characterization of biochar-amended soils and risk assessment approaches for surface and groundwater protection.

  5. Aquatic animal resources in Prehistoric Aegean, Greece.

    PubMed

    Mylona, Dimitra

    2014-12-01

    This paper explores the early stages in the history of fishing in the Aegean Sea in Greece, and highlights its formative phases and its specific characteristics in different points in time. This is testified by various physical remains, such as fish bones, fishing tools, and representations in art, which are gathered in the course of archaeological research. The aquatic resources in the Aegean Sea have been exploited and managed for millennia by communities that lived near the water and often made a living from it. The earliest evidence for a systematic, intensive exploitation of marine resources in the Aegean Sea dates to the Mesolithic, eleven millennia ago. In the Neolithic period, the adoption of a sedentary, agro-pastoral way of life led to a reduction in the intensity of fishing and shellfish gathering. Its importance as an economic resource remained high only in certain regions of rich, eutrophic waters. In the Bronze Age, an era of social complexity and centralized economy, the exploitation of aquatic, mostly marine, resources became a complex, multi-faceted activity which involved subsistence, industry and ideology. The range of preferred fish and invertebrate species, the fishing technology, and the processing of fish and shellfish in order to produce elaborate foods or prestige items are all traceable aspects of the complex relationship between humans and the aquatic resources throughout the prehistory of fishing and shellfish gathering in the Aegean area. The broadening of collaboration between archaeology and physical sciences offers new means to explore these issues in a more thorough and nuanced manner. PMID:25984485

  6. Restoration of aquatic ecosystems: Science, technology, and public policy

    SciTech Connect

    Not Available

    1992-01-01

    Aquatic ecosystems perform numerous valuable environmental functions. However, intensified industrial, commercial, and residential development in the US has led to the pollution of surface waters by fertilizers, insecticides, motor oil, toxic landfill leachates, and feedlot wastes while at the same time more water usage has lead to less water for dilution of wastes. Increased sediments from construction, agriculture and forestry has also heavily damaged aquatic ecosystems. Restorating aquatic ecosystems may be accomplished in stages, and in certain situations, partial ecological restoration may be the operant management goal, providing significant ecological benefits even though full restoration is not attained. A large scale aquatic ecosystem restoration program in the US should do as follows: (1) correct nonpoint source pollution problems; (2) arrest the decline of wildlife populations; (3) restore all types of wildlife habitats with priority to endangered species habitat. A national aquatic ecosystem strategy is recommended including four elements: (1) national restoration goals and assessment strategies for each ecoregion; (2) principles for priority setting and decision making; (3) policy and program redesign; (4) Innovation in financing and use of land and water markets. Major sections of the report discuss the following areas in detail: Overview of long-term, large scale coordinated restoration-planning, evaluating, and monitoring; Lakes (largest section); Rivers and Stream; and Wetlands.

  7. Aquatic CAM photosynthesis: a brief history of its discovery

    USGS Publications Warehouse

    Keeley, Jon E.

    2014-01-01

    Aquatic CAM (Crassulacean Acid Metabolism) photosynthesis was discovered while investigating an unrelated biochemical pathway concerned with anaerobic metabolism. George Bowes was a significant contributor to this project early in its infancy. Not only did he provide me with some valuable perspectives on peer review rejections, but by working with his gas exchange system I was able to take our initial observations of diel fluctuations in malic acid to the next level, showing this aquatic plant exhibited dark CO2 uptake. CAM is universal in all aquatic species of the worldwide Lycophyta genus Isoetes and non-existent in terrestrial Isoetes. Outside of this genus aquatic CAM has a limited occurrence in three other families, including the Crassulaceae. This discovery led to fascinating adventures in the highlands of the Peruvian Andes in search of Stylites, a terrestrial relative of Isoetes. Stylites is a plant that is hermetically sealed from the atmosphere and obtains all of its carbon from terrestrial sources and recycles carbon through CAM. Considering the Mesozoic origin of Isoetes in shallow pools, coupled with the fact that aquatic Isoetes universally possess CAM, suggests the earliest evolution of CAM photosynthesis was most likely not in terrestrial plants.

  8. An aquatic ecosystem in space.

    PubMed

    Voeste, D; Andriske, M; Paris, F; Levine, H G; Blum, V

    1999-07-01

    The Closed Equilibrated Biological Aquatic System (CEBAS) Mini-Module experiment was designed to study aquatic ecosystem performance within a middeck locker on the Space Shuttle. CEBAS was flown aboard STS-89 in January 1998 with a population of four pregnant Xiphophorus helleri female fish and eleven adult Biomphalaria glabrata snails in the first compartment and 200 juvenile X. helleri and 48 adult and juvenile B. glabrata in the second compartment. A plant compartment contained eleven snails and 53 g of the aquatic angiosperm Ceratophyllum demersum. During the flight, Ceratophyllum fresh weight increased from 53 g to 117 g. All adult fish and 65 juveniles survived the flight experiment and 37 adult snails and 40 newly laid snail spawn packs were recovered after the flight. Oxygen production and pH were as expected.

  9. Oviposition site choice under conflicting risks demonstrates that aquatic predators drive terrestrial egg-laying.

    PubMed

    Touchon, Justin C; Worley, Julie L

    2015-06-01

    Laying eggs out of water was crucial to the transition to land and has evolved repeatedly in multiple animal phyla. However, testing hypotheses about this transition has been difficult because extant species only breed in one environment. The pantless treefrog, Dendropsophus ebraccatus, makes such tests possible because they lay both aquatic and arboreal eggs. Here, we test the oviposition site choices of D. ebraccatus under conflicting risks of arboreal egg desiccation and aquatic egg predation, thereby estimating the relative importance of each selective agent on reproduction. We also measured discrimination between habitats with and without predators and development of naturally laid aquatic and arboreal eggs. Aquatic embryos in nature developed faster than arboreal embryos, implying no cost to aquatic egg laying. In choice tests, D. ebraccatus avoided habitats with fish, showing that they can detect aquatic egg predators. Most importantly, D. ebraccatus laid most eggs in the water when faced with only desiccation risk, but switched to laying eggs arboreally when desiccation risk and aquatic predators were both present. This provides the first experimental evidence to our knowledge that aquatic predation risk influences non-aquatic oviposition and strongly supports the hypothesis that it was a driver of the evolution of terrestrial reproduction. PMID:25948689

  10. Oviposition site choice under conflicting risks demonstrates that aquatic predators drive terrestrial egg-laying

    PubMed Central

    Touchon, Justin C.; Worley, Julie L.

    2015-01-01

    Laying eggs out of water was crucial to the transition to land and has evolved repeatedly in multiple animal phyla. However, testing hypotheses about this transition has been difficult because extant species only breed in one environment. The pantless treefrog, Dendropsophus ebraccatus, makes such tests possible because they lay both aquatic and arboreal eggs. Here, we test the oviposition site choices of D. ebraccatus under conflicting risks of arboreal egg desiccation and aquatic egg predation, thereby estimating the relative importance of each selective agent on reproduction. We also measured discrimination between habitats with and without predators and development of naturally laid aquatic and arboreal eggs. Aquatic embryos in nature developed faster than arboreal embryos, implying no cost to aquatic egg laying. In choice tests, D. ebraccatus avoided habitats with fish, showing that they can detect aquatic egg predators. Most importantly, D. ebraccatus laid most eggs in the water when faced with only desiccation risk, but switched to laying eggs arboreally when desiccation risk and aquatic predators were both present. This provides the first experimental evidence to our knowledge that aquatic predation risk influences non-aquatic oviposition and strongly supports the hypothesis that it was a driver of the evolution of terrestrial reproduction. PMID:25948689

  11. Comparative acute toxicities of surfactants to aquatic invertebrates

    SciTech Connect

    Lewis, M.A.; Suprenant, D.

    1983-06-01

    Investigations of the toxicity of surfactants to aquatic invertebrates have been limited primarily to determining the effects on a few species. In this study, the 48-hr LC50 values for three surfactants are reported for six species of aquatic invertebrates. The acute toxicities (LC50) for each surfactant (mg/liter) varied 159 to 580 X and were as follows: C11.8LAS (anionic), 1.7 (Dero sp.) to 270 (Asellus sp.); C14-15 alkylethoxylate (nonionic), 1.0 (Dugesia sp.) to 6.8 (Rhabditis sp.); CTAC (cationic), 0.1 (Gammarus sp.) to 58 (Asellus sp.). When compared to previously developed data, Daphnia magna was typically found to be the most sensitive of all species tested, including fish, to the surfactants.

  12. Selection of candidate aquatic high plants as producer of closed aquatic ecosystem

    NASA Astrophysics Data System (ADS)

    Wang, Gaohong; Hao, Zongjie; Liu, Yongding

    Controlled Ecological Life Support Systems (CELSS) is very important for long-term manned space flight. Aquatic organism was regarded to be suitable for this study because of their great adaptation to the weightless condition which approximate to their wild condition in water. In order to study of operation of CELSS in space, the first step is to choose good candidate species for study. In this report, we compared the characteristics of nutrient content, growth and suitability with animals among five types of aquatic high plants including Ceratophyllum demersum L., Vallisneria spiralis L., Hydrilla verticillata Royle, Brasenia schreberi, Wolfia arrhiza under control condition. It was found that B. schreberi had the best nutrients content, but it growth depended on gas interface which may be a big problem in microgravity. C. demersum and W. arrhiza had the better nutrient content than other types, and V. spiralis and H. verticillata had the worst nutrient content. The closed aquatic system can provided condition for the growth of other plants than B. schreberi. So we selected C. demersum and W. arrhiza as the candidate of producer for establish Closed Aquatic Ecosystem. We also established a simple system& by housing three small freshwater snails (Bulinus australianus) and C. demersum in a 500mL box with light and temperature control. The values about pH, oxygen concentration, temperature and light had been acquired by sensors in real time for about 3 month. It was found that plant's biomass increased for several days and then leveled off and the snails survive, and the atmosphere and biomass for food met snails' requirement during experiments.

  13. Energy flow in an arctic aquatic ecosystem

    SciTech Connect

    Schell, D.M.

    1988-01-01

    Natural isotope abundances to trace major pathways of energy flow to consumers in Imnavait Creek and the tundra ecosystem of the R4D watershed with comparative work in the coastal tundra. Our overall goals are to a determine if carbon is accumulating in upland and coastal tundra; determine the role of eroded peat carbon in the aquatic ecosystem; and to determine the distribution of carbon and nitrogen isotopes in the tundra-pond ecosystem to establish the feasibility of using natural differences as tracers. Past work on fishes, birds, and the prey species of insects and aquatic crustaceans has shown that peat carbon is very important in the energy supply supporting the food webs over the course of the year. Obligate freshwater fishes from the coastal lakes and Colville River have been shown to contain up to 60 percent peat carbon at the end of the winter season. In contrast, migratory shorebirds and passerines contained much smaller radiocarbon abundances in summer, indicating a major shift to recent in situ primary production in pond and stream ecosystems in summer months. For the past two years, we have narrowed our focus to the processes supplying carbon to the beaded stream system at MS-117 and have concentrated on determining the transfer and accumulation rates of carbon in the watershed.

  14. Energy flow in an arctic aquatic ecosystem

    SciTech Connect

    Schell, D.M.

    1988-12-31

    Natural isotope abundances to trace major pathways of energy flow to consumers in Imnavait Creek and the tundra ecosystem of the R4D watershed with comparative work in the coastal tundra. Our overall goals are to a determine if carbon is accumulating in upland and coastal tundra; determine the role of eroded peat carbon in the aquatic ecosystem; and to determine the distribution of carbon and nitrogen isotopes in the tundra-pond ecosystem to establish the feasibility of using natural differences as tracers. Past work on fishes, birds, and the prey species of insects and aquatic crustaceans has shown that peat carbon is very important in the energy supply supporting the food webs over the course of the year. Obligate freshwater fishes from the coastal lakes and Colville River have been shown to contain up to 60 percent peat carbon at the end of the winter season. In contrast, migratory shorebirds and passerines contained much smaller radiocarbon abundances in summer, indicating a major shift to recent in situ primary production in pond and stream ecosystems in summer months. For the past two years, we have narrowed our focus to the processes supplying carbon to the beaded stream system at MS-117 and have concentrated on determining the transfer and accumulation rates of carbon in the watershed.

  15. Ammonia excretion in aquatic and terrestrial crabs.

    PubMed

    Weihrauch, Dirk; Morris, Steve; Towle, David W

    2004-12-01

    The excretory transport of toxic ammonia across epithelia is not fully understood. This review presents data combined with models of ammonia excretion derived from studies on decapod crabs, with a view to providing new impetus to investigation of this essential issue. The majority of crabs preserve ammonotely regardless of their habitat, which varies from extreme hypersaline to freshwater aquatic environments, and ranges from transient air exposure to obligate air breathing. Important components in the excretory process are the Na+/K+(NH4+)-ATPase and other membrane-bound transport proteins identified in many species, an exocytotic ammonia excretion mechanism thought to function in gills of aquatic crabs such as Carcinus maenas, and gaseous ammonia release found in terrestrial crabs, such as Geograpsus grayi and Ocypode quadrata. In addition, this review presents evidence for a crustacean Rhesus-like protein that shows high homology to the human Rhesus-like ammonia transporter both in its amino acid sequence and in its predicted secondary structure. PMID:15579545

  16. Aquatic biodiversity assessment for the lazy.

    PubMed

    Hoffmann, Constanze; Schubert, Grit; Calvignac-Spencer, Sébastien

    2016-02-01

    The world is covered in DNA. In any ecosystem, extracellular DNA fragments can be found that once formed the genomes of a variety of micro- and macroorganisms. A few years ago, it was proposed to use this environmental DNA (eDNA) as a source of information on local vertebrate biodiversity (Ficetola et al. 2008; Taberlet et al. 2012). This idea offered an elegant solution to take up the gauntlet of rapidly increasing monitoring needs. Coupled with barcoding efforts, it promised to be cost-efficient in many respects, for example man-hours and taxonomic expertise. Ecologists and conservation biologists with an interest in aquatic ecosystems have enthusiastically adopted and pioneered this new method, producing dozens of eDNA studies. Most of these studies have, however, focused on a single or a few aquatic species. In this issue of Molecular Ecology, Valentini et al. (2016) move the field a step further by demonstrating that metabarcoding approaches - which simultaneously target large groups of organisms such as amphibians or fish - can match and sometimes even outperform other inventory methods. PMID:26876232

  17. Aquatic biodiversity assessment for the lazy.

    PubMed

    Hoffmann, Constanze; Schubert, Grit; Calvignac-Spencer, Sébastien

    2016-02-01

    The world is covered in DNA. In any ecosystem, extracellular DNA fragments can be found that once formed the genomes of a variety of micro- and macroorganisms. A few years ago, it was proposed to use this environmental DNA (eDNA) as a source of information on local vertebrate biodiversity (Ficetola et al. 2008; Taberlet et al. 2012). This idea offered an elegant solution to take up the gauntlet of rapidly increasing monitoring needs. Coupled with barcoding efforts, it promised to be cost-efficient in many respects, for example man-hours and taxonomic expertise. Ecologists and conservation biologists with an interest in aquatic ecosystems have enthusiastically adopted and pioneered this new method, producing dozens of eDNA studies. Most of these studies have, however, focused on a single or a few aquatic species. In this issue of Molecular Ecology, Valentini et al. (2016) move the field a step further by demonstrating that metabarcoding approaches - which simultaneously target large groups of organisms such as amphibians or fish - can match and sometimes even outperform other inventory methods.

  18. Aquatic macroinvertebrates of the Grand Calumet River

    USGS Publications Warehouse

    Last, Laurel L.; Whitman, Richard L.

    2000-01-01

    The Grand Calumet River is potential habitat for a rich community of aquatic macroinvertebrates. Historical surveys of these organisms have been limited to post-industrialization of the Calumet Region; but because river habitats and conditions prior to industrialization have been described, past macroinvertebrate composition can be inferred. In the past 20 years, several surveys have been conducted in the Grand Calumet that have focused on a limited area, but when these studies are amassed the information available covers much of the river. In this paper, the aquatic macroinvertebrate communities in the river are described, and options for restoration are discussed. Many of the macroinvertebrates present are indicators of high levels of pollution, but a few pollution-sensitive species have been found. There is evidence, however, that the sediment quality has improved since the 1960's, likely due to pollution controls that have been put into place. Restoration opportunities should consider the macroinvertebrate community and the potential to improve sediment habitat without damaging the community structure.

  19. Aquatic Plants and Animals as Ecosystem Engineers

    NASA Astrophysics Data System (ADS)

    Wotton, R. S.

    2005-05-01

    Studies on aquatic plants and animals focus on population dynamics, the structure of communities and the part played by organisms in food webs and other ecosystem processes. As Lawton and Jones point out in "Linking Species and Ecosystems", less attention is given to the role of organisms as ecosystem engineers, modifying the environment in which they live. Yet plants can have a profound effect on their surroundings, altering flow patterns and trapping large amounts of organic and inorganic material. Animals also affect aquatic ecosystems in many ways, both in building structures such as tubes and shelters, and in their feeding. For example, detritus feeders often produce large numbers of faecal pellets (and pseudofaeces in bivalves) and these are very different in size to the materials ingested. Pellets are deposited in masses over the bed of streams, lakes and the sea and therefore effect a translocation of nutrients. The action of plants and animals in altering their environment is likely to be a significant process in all water bodies, from both small to large scale.

  20. Polycyclic musk fragrances in the aquatic environment.

    PubMed

    Rimkus, G G

    1999-12-20

    demonstrates the persistence and lipophilicity of these pollutants. The high log K(ow) values of HHCB and AHTN (5.7-5.9) do not directly correlate with their relatively low bioconcentration factors (BCFs) derived from fish experiments, this discrepancy may be explained by a particular metabolism in fish. There are indications of a possible species dependent metabolisation. For a general risk assessment of this new group of environmental pollutants besides the missing toxicological data, further studies on the distribution of the polycyclic musk fragrances including their by-products in the aquatic environment, on possible degradation processes in sediment/sludge as well as on the metabolism in fish are urgently needed.