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Fish Health and Toxic Contaminants

Fish kills, skin lesions, and fish consumption advisories have raised concerns about the health of fish across the watershed. The USGS is working to identify the multiple factors that affect fisheries including toxic contaminants, disease, pathogens, and poor habitat conditions. 

Filter Total Items: 23

Observed monitoring data and predictive modelling help understand ongoing and future vulnerability of Chesapeake Bay watershed stream fish communities to climate and land-use change

Issue: The Chesapeake Bay Watershed (CBW) is experiencing effects of climate (warming temperatures and shifting precipitation patterns) and land-use/land-cover (LULC; transition from forest or agriculture to developed lands) change, and these trends are likely to continue under future scenarios of warming and population growth. Stream biodiversity may be vulnerable to ongoing and future climate...
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Observed monitoring data and predictive modelling help understand ongoing and future vulnerability of Chesapeake Bay watershed stream fish communities to climate and land-use change

Issue: The Chesapeake Bay Watershed (CBW) is experiencing effects of climate (warming temperatures and shifting precipitation patterns) and land-use/land-cover (LULC; transition from forest or agriculture to developed lands) change, and these trends are likely to continue under future scenarios of warming and population growth. Stream biodiversity may be vulnerable to ongoing and future climate...
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A case study of temporal trends in risk factors associated with endocrine disruption in smallmouth bass

Issue The USGS has a long-term research effort that identified endocrine disruption in smallmouth bass (SMB) in the Chesapeake Bay watershed. Endocrine disruption can cause many changes in fish, including intersex characteristics where fish develop characteristics of the other sex, such as immature eggs forming in males. An overview by USGS of endocrine disruption in fish found the condition...
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A case study of temporal trends in risk factors associated with endocrine disruption in smallmouth bass

Issue The USGS has a long-term research effort that identified endocrine disruption in smallmouth bass (SMB) in the Chesapeake Bay watershed. Endocrine disruption can cause many changes in fish, including intersex characteristics where fish develop characteristics of the other sex, such as immature eggs forming in males. An overview by USGS of endocrine disruption in fish found the condition...
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Tracking Status and Trends in Seven Key Indicators of River and Stream Condition in the Chesapeake Bay Watershed

Identifying and tracking the status of, and trends in, stream health within the Chesapeake Bay watershed is essential to understanding the past, present, and future trajectory of the watershed’s resources and ecological condition. A team of USGS ecosystem scientists is meeting this need with an initiative to track the status of, and trends in, key indicators of the health of non-tidal freshwater...
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Tracking Status and Trends in Seven Key Indicators of River and Stream Condition in the Chesapeake Bay Watershed

Identifying and tracking the status of, and trends in, stream health within the Chesapeake Bay watershed is essential to understanding the past, present, and future trajectory of the watershed’s resources and ecological condition. A team of USGS ecosystem scientists is meeting this need with an initiative to track the status of, and trends in, key indicators of the health of non-tidal freshwater...
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The statistical power to detect regional temporal trends in riverine contaminants in the Chesapeake Bay Watershed

Issue: Chemical contamination of riverine ecosystems is a global concern, with potentially negative effects for human and ecological health. Land management activities (e.g., Best Management Practices; BMPs) are an important tool that can be used to reduce point and non-point sources of pollution. The Chesapeake Bay Program (CBP) has goals for (1) reducing toxic contaminants and (2) reducing...
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The statistical power to detect regional temporal trends in riverine contaminants in the Chesapeake Bay Watershed

Issue: Chemical contamination of riverine ecosystems is a global concern, with potentially negative effects for human and ecological health. Land management activities (e.g., Best Management Practices; BMPs) are an important tool that can be used to reduce point and non-point sources of pollution. The Chesapeake Bay Program (CBP) has goals for (1) reducing toxic contaminants and (2) reducing...
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USGS Integrates Findings about Endocrine-Disrupting Compounds in the Chesapeake Watershed

Issue: Studies in the Chesapeake Bay Watershed have documented the exposure of fish to toxic contaminants including endocrine-disrupting compounds (EDCs) - compounds which can alter normal hormonal function in organisms. Given the importance of fisheries to the economic and environmental health of the Watershed, observed endocrine disruption and fish kills in the Watershed have raised public and...
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USGS Integrates Findings about Endocrine-Disrupting Compounds in the Chesapeake Watershed

Issue: Studies in the Chesapeake Bay Watershed have documented the exposure of fish to toxic contaminants including endocrine-disrupting compounds (EDCs) - compounds which can alter normal hormonal function in organisms. Given the importance of fisheries to the economic and environmental health of the Watershed, observed endocrine disruption and fish kills in the Watershed have raised public and...
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Occurrence of toxic contaminant mixtures in surface water and groundwater in agricultural watersheds of the Chesapeake Bay

Issue The widespread use of pesticides and fertilizers, application of biosolids and manure, and large-scale animal feeding operations result in contaminant mixtures occurring in streams and rivers (figure 1). These nonpoint sources are affected by multiple processes (such as stream discharge, seasonality and management practices) that influence contaminant occurrence in surface and groundwater...
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Occurrence of toxic contaminant mixtures in surface water and groundwater in agricultural watersheds of the Chesapeake Bay

Issue The widespread use of pesticides and fertilizers, application of biosolids and manure, and large-scale animal feeding operations result in contaminant mixtures occurring in streams and rivers (figure 1). These nonpoint sources are affected by multiple processes (such as stream discharge, seasonality and management practices) that influence contaminant occurrence in surface and groundwater...
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Bioaccumulation of Mercury in Fish Varied by Species and Location in the Chesapeake Bay Watershed—Summary of Existing Data and a Roadmap for Integrated Monitoring

Fish mercury data from State monitoring programs and research studies within the Chesapeake Bay were compiled and summarized to provide a comprehensive overview of the variation in fish mercury concentrations among species and habitats within the watershed. These data are put into context with existing health benchmarks for humans, birds, and fish. Scientists also provide a roadmap for an...
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Bioaccumulation of Mercury in Fish Varied by Species and Location in the Chesapeake Bay Watershed—Summary of Existing Data and a Roadmap for Integrated Monitoring

Fish mercury data from State monitoring programs and research studies within the Chesapeake Bay were compiled and summarized to provide a comprehensive overview of the variation in fish mercury concentrations among species and habitats within the watershed. These data are put into context with existing health benchmarks for humans, birds, and fish. Scientists also provide a roadmap for an...
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USGS Contributes to Revised Plans for Chesapeake Water-Quality and Toxic Contaminant Goal

Issue: The Chesapeake Bay Program (CBP), through the Strategic Review System (SRS), reviews progress toward the 10 goals and associated outcomes of the Chesapeake Watershed Agreement. Each outcome is managed by a specific CBP Goal Implementation Team and their associated workgroups. During review of each outcome every two years, a workgroup is responsible to prepare materials for (1) summarizing...
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USGS Contributes to Revised Plans for Chesapeake Water-Quality and Toxic Contaminant Goal

Issue: The Chesapeake Bay Program (CBP), through the Strategic Review System (SRS), reviews progress toward the 10 goals and associated outcomes of the Chesapeake Watershed Agreement. Each outcome is managed by a specific CBP Goal Implementation Team and their associated workgroups. During review of each outcome every two years, a workgroup is responsible to prepare materials for (1) summarizing...
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Land-use influences on estrogenic-endocrine disruption in fish within the Chesapeake Bay watershed

Issue: Effects of exposure to estrogenic-chemical contaminants have been observed in many fish species worldwide. One effect is described as “intersex” because fish will take on characteristics of the other sex, such as immature eggs forming in male fish. Studies in the Chesapeake Bay watershed have also identified the exposure of fish to endocrine-disrupting compounds. The estrogenic-endocrine...
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Land-use influences on estrogenic-endocrine disruption in fish within the Chesapeake Bay watershed

Issue: Effects of exposure to estrogenic-chemical contaminants have been observed in many fish species worldwide. One effect is described as “intersex” because fish will take on characteristics of the other sex, such as immature eggs forming in male fish. Studies in the Chesapeake Bay watershed have also identified the exposure of fish to endocrine-disrupting compounds. The estrogenic-endocrine...
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New Findings on Toxic Contaminants in the Chesapeake Watershed

Issue: The Chesapeake Bay Program has a goal to reduce the impacts of toxic contaminants on living resources in the Bay and its watershed. USGS leads the toxic contaminant outcome on research to increase our understanding of the impacts and mitigation options for toxic contaminants.
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New Findings on Toxic Contaminants in the Chesapeake Watershed

Issue: The Chesapeake Bay Program has a goal to reduce the impacts of toxic contaminants on living resources in the Bay and its watershed. USGS leads the toxic contaminant outcome on research to increase our understanding of the impacts and mitigation options for toxic contaminants.
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Changing Freshwater Flows Affect Fish Populations in the Potomac River

Issue: Millions of people rely on the Potomac River for drinking water and recreational opportunities. The Potomac is Maryland’s most popular freshwater fishing destination, and the second largest river that enters the Chesapeake Bay. Restoring fisheries is also an important goal for the Chesapeake Bay Partnership restoration efforts.
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Changing Freshwater Flows Affect Fish Populations in the Potomac River

Issue: Millions of people rely on the Potomac River for drinking water and recreational opportunities. The Potomac is Maryland’s most popular freshwater fishing destination, and the second largest river that enters the Chesapeake Bay. Restoring fisheries is also an important goal for the Chesapeake Bay Partnership restoration efforts.
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Refined Model Provides a Screening Tool to Understand Exposure to Contaminants from Incidental Wastewater Reuse

Refinement of the existing national-scale “de facto reuse incidence in our nation’s consumable supply” (DRINCS) model, complemented by field measurements, provides a screening tool to understand human and wildlife exposure to toxicants and pathogens associated with the incidental reuse of treated wastewater in the Shenandoah River watershed. The model results can be accessed in a companion web...
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Refined Model Provides a Screening Tool to Understand Exposure to Contaminants from Incidental Wastewater Reuse

Refinement of the existing national-scale “de facto reuse incidence in our nation’s consumable supply” (DRINCS) model, complemented by field measurements, provides a screening tool to understand human and wildlife exposure to toxicants and pathogens associated with the incidental reuse of treated wastewater in the Shenandoah River watershed. The model results can be accessed in a companion web...
Learn More