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Wildlife & Habitat


  • Birds

    The refuge includes many high-quality habitats; this is reflected in the diversity and abundance of wildlife species. More than 150 species of birds dominate the landscape during spring and summer. The thousands of ponds and lakes distributed across the refuge provide breeding habitat for a variety of waterbirds; including ducks, loons, geese, swans, and shorebirds. Of national and international significance are the waterfowl that travel to the Yukon Flats from 11 foreign countries, eight Canadian provinces, and 43 of the 50 states. The refuge hosts as many as two million ducks annually, and supports the highest breeding densities in Alaska. Most of the canvasback ducks that nest in Alaska do so on the Yukon Flats.Songbirds breed and nest throughout the refuge. A songbird banding station on the refuge included one of the highest capture rates in the state. View the refuge bird species checklist.

  • Mammals

    Moose are found in relatively low numbers throughout the refuge. In winter, they congregate in the Yukon River valley where they find shelter and food. In summer, they are found dispersed throughout the refuge, typically near ponds and marshes. Caribou and sheep are found in low densities in the upland regions on the periphery of the refuge. Black and grizzly bears occur throughout the refuge, with the more abundant black bears found primarily in the forested lowlands. Wolves are also an important component of the ecosystem and are found throughout the refuge. Furbearer resources are rich and include beaver, fox, lynx, marten, muskrat, otter, weasel, and wolverine. View the refuge mammal species checklist. For more information on moose management, view the Yukon Flats Moose Management Plan 

  • Fish

    The Yukon River, along with 10 other major river drainages and more than 20,000 lakes, provides habitat for 18 species of fish on the refuge. The chinook (king), chum (dog), and coho (silver) salmon that pass through the refuge travel farther from the sea (as much as 2,000 miles!) to their spawning areas than do the salmon of any other river system in the world.  Important spawning grounds for salmon and inconnu (sheefish) occur within the refuge.  Resident fish in the Yukon Flats include Arctic grayling, burbot, northern pike, and several species of whitefish. View the refuge fish species checklist 

  • Amphibians

    Only one amphibian, the wood frog (Rana sylvatica), is found on the refuge. This small frog, averaging 2.5 inches long, inhabits a variety of habitats, but is commonly found along shorelines. It hibernates in shallow depressions in the upper layer of the previous year’s dead vegetation. The wood frog is able to survive winter cold by increasing the glucose stored in the cell fluids; the glucose acts as an antifreeze and prevents skin cells from freezing.

  • Invertebrates

    The health of refuge ecosystems is dependent upon the diversity of invertebrates that support plants and wildlife either directly or indirectly. No comprehensive inventory of invertebrates has occurred on the refuge 

Last Updated: Apr 17, 2014
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