Fish

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

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.

Where glaciers meet the sea in the Gulf of Alaska (GOA), they create unique and productive marine habitats. Ringed by the continent’s tallest coastal mountains, 20% of the GOA coastal watershed is covered by glacial ice and the annual freshwater discharge into the GOA from glacial melt is comparable to that of the Mississippi river.

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

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...

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).

In the Arctic, rivers often freeze all the way to the bottom each winter leaving fish with limited habitat where they can survive.

In addition to the direct effects of sea ice loss on walrus ( Odobenus rosmarus divergens) and polar bears ( Ursus maritimus) that use ice as a platform, the decline of Arctic sea ice is predicted to promote a fundamental ecosystem shift from benthic animals that forage on the sea floor to pelagic animals that forage near the sea surface.

High latitude ecosystems are among the most vulnerable to long-term climate change, yet continuous, multidecadal indicators by which to gauge effects on biology are scarce, especially in freshwater environments.

Permafrost thaw is leading to a myriad of changes in physical and chemical conditions throughout the Arctic.

The potential for invasive species introductions in Arctic and Subarctic ecosystems is growing as climate change manifests and human activity increases in high latitudes.

The physiological challenge for anadromous fish to migrate upriver to spawn and complete their life cycle is influenced by river temperature.