Koyukuk National Wildlife Refuge totals almost 4 million acres, and encompasses a vast floodplain containing 14 rivers, hundreds of streams, and thousands of lakes surrounded by low hills covered by boreal forest.
Refuge habitats include large expanses of black and white spruce forests, willows, alders, and aspen. Thousands of small lakes, marshes, and streams connecting one another create magnificent aquatic and upland habitats for birds, mammals and fish. More than 400,000 ducks and geese migrate south from the refuge each year. Moose, black and grizzly bear, wolves, lynx, otter, beaver, marten, and other furbearers are also abundant. Three species of Pacific salmon spawn in the Koyukuk River and its tributaries. Local village residents (Athabascan Indians) are dependent on all of these resources for sustenance.
Besides the varied wildlife, an unusual geological feature exists within the refuge - the Nogahabara Sand Dunes, featuring 25 miles of sand with sparse vegetation.
