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Fish and Aquatic Species

The USGS is the only federal science agency dedicated to providing independent research that supports the conservation and management of the nation’s fisheries. Our researchers develop and apply specialized tools such as genetic tracking, hydrologic modeling, and fish disease diagnostics to answer the most pressing questions facing federal, Tribal, state, and local resource managers.

Filter Total Items: 153

Conservation and Restoration of Native Freshwater Mussels

Freshwater mussels are the most imperiled group of animals in North America, with 66% of species at risk. Mussel populations are declining globally, but the factors contributing to these declines are largely unknown. Habitat fragmentation and alteration, point- and non-point source pollution, navigation-related impacts, and exotic species introductions are thought to be responsible for mussel...
Conservation and Restoration of Native Freshwater Mussels

Conservation and Restoration of Native Freshwater Mussels

Freshwater mussels are the most imperiled group of animals in North America, with 66% of species at risk. Mussel populations are declining globally, but the factors contributing to these declines are largely unknown. Habitat fragmentation and alteration, point- and non-point source pollution, navigation-related impacts, and exotic species introductions are thought to be responsible for mussel...
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Hydroacoustic mapping of habitat for threatened and endangered native mussels in the Upper Mississippi River

Understanding the distribution of threatened and endangered freshwater mussels is needed to conserve and restore populations. Sampling for native freshwater mussels typically involves taking quadrat samples in soft substrates and counting the number of mussels in a defined area. However, this methodology is unsuitable for detecting populations of the Spectaclecase mussel ( Margaritifera monodonta...
Hydroacoustic mapping of habitat for threatened and endangered native mussels in the Upper Mississippi River

Hydroacoustic mapping of habitat for threatened and endangered native mussels in the Upper Mississippi River

Understanding the distribution of threatened and endangered freshwater mussels is needed to conserve and restore populations. Sampling for native freshwater mussels typically involves taking quadrat samples in soft substrates and counting the number of mussels in a defined area. However, this methodology is unsuitable for detecting populations of the Spectaclecase mussel ( Margaritifera monodonta...
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Native Freshwater Mussel Health

Native freshwater mussels are a keystone species and are considered both ecosystem engineers, improving habitat for other species, and indicator species important in assessing the health of the ecosystem.
Native Freshwater Mussel Health

Native Freshwater Mussel Health

Native freshwater mussels are a keystone species and are considered both ecosystem engineers, improving habitat for other species, and indicator species important in assessing the health of the ecosystem.
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Comparative Freshwater Fish Toxicity Testing of Antimycin A

Researchers are investigating the influence of Antimycin A on invasive carp and non-target fishes by measuring the effects of a novel species-specific bait formulation.
Comparative Freshwater Fish Toxicity Testing of Antimycin A

Comparative Freshwater Fish Toxicity Testing of Antimycin A

Researchers are investigating the influence of Antimycin A on invasive carp and non-target fishes by measuring the effects of a novel species-specific bait formulation.
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Temporal and spatial patterning of aquatic macroinvertebrate communities in response to changing environmental conditions

An increased understanding of prairie-pothole-wetland macroinvertebrate dynamics is crucial to better inform conservation strategies related to waterfowl production, biodiversity enhancement, and wetland function/health maintenance. Wetlands in general are highly variable in space and time, and wetland macroinvertebrates are adapted to this great variability. Wetland ecosystems are also influenced...
Temporal and spatial patterning of aquatic macroinvertebrate communities in response to changing environmental conditions

Temporal and spatial patterning of aquatic macroinvertebrate communities in response to changing environmental conditions

An increased understanding of prairie-pothole-wetland macroinvertebrate dynamics is crucial to better inform conservation strategies related to waterfowl production, biodiversity enhancement, and wetland function/health maintenance. Wetlands in general are highly variable in space and time, and wetland macroinvertebrates are adapted to this great variability. Wetland ecosystems are also influenced...
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Condition of Forage Fish in Prince William Sound During the Marine Heatwave

Changes in the body condition of a key forage fish species, Pacific sand lance ( Ammodytes personatus), are examined to understand how energy transfer to predators may have been disrupted during the recent marine heatwave in the North Pacific (late 2013 to mid 2016).
Condition of Forage Fish in Prince William Sound During the Marine Heatwave

Condition of Forage Fish in Prince William Sound During the Marine Heatwave

Changes in the body condition of a key forage fish species, Pacific sand lance ( Ammodytes personatus), are examined to understand how energy transfer to predators may have been disrupted during the recent marine heatwave in the North Pacific (late 2013 to mid 2016).
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Quantitative and Other Methods

Applying quantitative methods to evaluate ecological hypotheses for wild animal populations is inherently challenging due to the complexity of ecological systems and the sampling process that is used to monitor them.
Quantitative and Other Methods

Quantitative and Other Methods

Applying quantitative methods to evaluate ecological hypotheses for wild animal populations is inherently challenging due to the complexity of ecological systems and the sampling process that is used to monitor them.
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Passage Technologies for American Eels

The American eel ( Anguilla rostrata) migrates into freshwater in the juvenile (glass eel and elver) stage, feeds and grows in freshwater habitats, and migrates downstream to the ocean to spawn as an adult. Migrating eels frequently encounter barriers in river environments, primarily in the form of dams, that limit access of juveniles to upstream growth habitat, and can injure or kill adult...
Passage Technologies for American Eels

Passage Technologies for American Eels

The American eel ( Anguilla rostrata) migrates into freshwater in the juvenile (glass eel and elver) stage, feeds and grows in freshwater habitats, and migrates downstream to the ocean to spawn as an adult. Migrating eels frequently encounter barriers in river environments, primarily in the form of dams, that limit access of juveniles to upstream growth habitat, and can injure or kill adult...
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Restoring a native fish to Catoctin Mountain Park

Native species conservation is a fundamental purpose of National Parks. Catoctin Mountain Park (CATO) in Maryland supports a prized trout fishery and a healthy community of native fishes, with one exception: native Blue Ridge Sculpin ( Cottus caeruleomentum) appear to have been extirpated from Big Hunting Creek above Cunningham Falls. Infection by a fungal-like protist Dermocystidium is...
Restoring a native fish to Catoctin Mountain Park

Restoring a native fish to Catoctin Mountain Park

Native species conservation is a fundamental purpose of National Parks. Catoctin Mountain Park (CATO) in Maryland supports a prized trout fishery and a healthy community of native fishes, with one exception: native Blue Ridge Sculpin ( Cottus caeruleomentum) appear to have been extirpated from Big Hunting Creek above Cunningham Falls. Infection by a fungal-like protist Dermocystidium is...
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Exploring the potential effects of shale oil and gas development on freshwaters

Widespread shale oil and gas (unconventional oil and gas, UOG) has only recently begun and many gaps in our knowledge of its potential effects to freshwaters exist.
Exploring the potential effects of shale oil and gas development on freshwaters

Exploring the potential effects of shale oil and gas development on freshwaters

Widespread shale oil and gas (unconventional oil and gas, UOG) has only recently begun and many gaps in our knowledge of its potential effects to freshwaters exist.
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A hydrological framework to improve precision of Vital Signs metrics in the Appalachian highlands

Stream flow is a fundamental driver of ecological structure and function, but its influence on bioassessment measures is poorly understood. Although extreme flow conditions (e.g., floods and droughts) have long been known to play a central role in structuring stream communities, a mechanistic understanding of the linkages between flow variables, landscape and local physical characteristics, and...
A hydrological framework to improve precision of Vital Signs metrics in the Appalachian highlands

A hydrological framework to improve precision of Vital Signs metrics in the Appalachian highlands

Stream flow is a fundamental driver of ecological structure and function, but its influence on bioassessment measures is poorly understood. Although extreme flow conditions (e.g., floods and droughts) have long been known to play a central role in structuring stream communities, a mechanistic understanding of the linkages between flow variables, landscape and local physical characteristics, and...
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Fish locomotion and biomechanics as limiting and optimizing factors in fish passage

Swimming ability determines how well fish are able to access habitat, and is a fundamental design consideration for passing fish at dams, road crossings, etc.
Fish locomotion and biomechanics as limiting and optimizing factors in fish passage

Fish locomotion and biomechanics as limiting and optimizing factors in fish passage

Swimming ability determines how well fish are able to access habitat, and is a fundamental design consideration for passing fish at dams, road crossings, etc.
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