Fish and Aquatic Species

We will examine evidence of heat stress in Yukon River Chinook salmon ( Oncorhynchus tshawytscha ) using heat shock proteins and gene expression.

Fish and aquatic habitats in Alaska support important commercial, sport, and subsistence fisheries and provide forage fish that support wildlife populations. The USGS Alaska Science Center conducts interdisciplinary research to inform local, state, federal, and international policy makers regarding conservation of fish, aquatic species, and their habitats. We work collaboratively with hydrologists...

Nearshore systems provide habitat to a unique community of marine and diadromous (lives in both fresh and saltwater) fish and support high fish abundance.

USGS scientists are studying the passage, migration and critical habitat of the Atlantic ( Acipenser oxyrhinchus oxyrhinchus ) and shortnose ( Acipenser brevirostrum ) sturgeon in New England waters to provide managers with population-specific details upon which effective steps can be taken to protect these endangered species.

USGS is working with many partners to help reptiles, amphibians and other animals cross roads safely, improving access to essential habitat.

USGS scientists are using innovative combinations of telemetry, genetics, and side-scan Sonar to support conservation of endangered Atlantic sturgeon ( Acipenser o. oxyrinchus) .

USGS is working with federal, state and local partners to develop multiple assessments of stream and river conditions in non-tidal areas of the Chesapeake Bay watershed. These assessments will help managers preserve stream health and improve biological conditions in impaired streams as the human population and climate continue to change in this region.

Alaska's coastal and offshore waters provide foraging habitat for an estimated 100 million birds comprising more than 90 different species; from loons and seaducks that nest inland, to petrels and puffins that breed on islands off shore. All these birds depend on the sea to provide a wide variety of food types— from clams, crabs and urchins nearshore— to krill, forage fish, and squid offshore. The...

Rainbow trout are a desirable sport fish that have been introduced in many locations around the world, including the Colorado River. Although introductions of rainbow trout and other nonnative fishes provide recreational fishing opportunities, they can also pose threats to native fish populations. The Glen Canyon Dam Adaptive Management Program has tasked scientists and managers with identifying...

Forage fish are small pelagic schooling fish that play a key role in transferring energy between plankton and top marine predators. Many seabirds, marine mammals, and commercial fish species depend on forage fish to grow and survive.

The emerging field of Environmental DNA (eDNA) analysis allows characterization of species presence and community biodiversity by identifying trace amounts of genetic material left behind as organisms move through their environments. EESC scientists have been using eDNA technologies to detect native and rare species and as community biomonitoring tools.

USGS' and Loyola University New Orleans' innovative research techniques played a role in the decision to downlist the Okaloosa Darter, a freshwater fish endemic to northwest Florida, from Endangered to Threatened in 2011, and the removal of the fish from the U.S. Endangered Species Act in 2023.