Fisheries & Ecological Services
Alaska Region


Environmental Contaminants

Wildlife Resources & Contaminants

Threatened, Endangered & Declining Species
Historically, environmental contaminants have been implicated in the decline of some wildlife populations. Therefore, the Service studies threatened and declining species in Alaska to assess the role contaminantsStellers-Eider may play in the decline of these populations. In addition to studying species listed under the Endangered Species Act, studies are also conducted on non-listed, declining species. Proactive investigation of factors contributing to these declines may help stem further population reductions and preclude future listing of these species.

Marine Mammals
The Service manages three marine mammal species (polar bear, sea otter and walrus). As top predators in the Arctic food web, polar bears bioaccumulate some persistent contaminants. Polar bears, therefore, may serve as sentinel species which reflect contaminant trends in the Arctic. Because both polar bears and walrus are harvested for subsistence, there is considerable interest in contaminants data for these species. While sea otters are not hunted for food, they frequent nearshore marine environments, where they are particularly vulnerable to spills. The nearshore distribution and site fidelity of sea otters contribute to their usefulness as a sentinel species. The Marine Mammal Management Office, in partnership with the Alaska Sea Otter and Steller Sea Lion Commission, maintains a biosampling program that incorporates contaminant analyses. Both polar bears and walrus inhabit marine habitats, and therefore must also be considered when evaluating the potential impact of spills on resources managed by the Service.

Migratory BirdsPeregrine Falcon Egg
Contaminants can affect various bird species managed by the Service. For example, seabirds are frequently impacted during marine oil spills. The Service may also study avian species experiencing population declines, species that are harvested for subsistence, or species that exhibit abnormalities or diseases that might be linked to contaminant exposure.

Anadromous and Interjurisdictional Fisheries
Salmon and other anadromous fish are vitally important subsistence resources for Alaska residents. When these fish return to spawning areas, they also are consumed by freshwater and terrestrial predators. Only recently have contaminants data been collected from salmon in Alaska. The Service (through our Fairbanks Fish and Wildlife Field Office) and the Alaska Department of Environmental Conservation have coordinated efforts in recent years to ensure that high quality data are obtained for Alaskan salmon.

Steller's Eider - Contaminants Study, Click to Enlarge


Last updated: March 23, 2010