Koyukuk National Wildlife Refuge Alaska Hero
Photo Credit: P.A. Lawrence, Alamy Stock Photo

Koyukuk National Wildlife Refuge

Koyukuk National Wildlife Refuge

Home to the third largest river in Alaska, this refuge in Interior Alaska provides year-round habitat for a variety of wildlife.

The 3.5 million-acre Koyukuk National Wildlife Refuge encompasses diverse ecosystems including wetlands, forests, and large sand dunes, bisected by the Koyukuk River and surrounded by rolling, low mountains.


Wildlife viewing is a year-round activity in the Koyukuk and Kaiyuh regions. Visitors in the springtime can view flocks of birds that use the refuge to nest. Bear viewing is prime in spring and early summer. Fall foliage provides a colorful backdrop for rutting bull moose and foraging bears and foxes. The winter is a time to learn about animal travel through tracks left imprinted in the snow. Caribou winter in the refuge, including the Western Arctic caribou herd. Other wildlife that can be seen in the refuge are wolves, lynx, wolverines, voles, and martens.

Photography and rafting are also popular in the refuge. The scenic rivers and mountains, wildlife, and the magic hues of the long northern twilight add to the beauty of the scenery.

Sport anglers are rewarded with some spectacular fishing at the refuge, with northern pike and sheefish found along virtually all of the refuges' rivers and tributaries. Arctic grayling are also found in several of the clear, fast-flowing streams that feed into the Koyukuk River.

Subsistence and sport hunting are allowed on refuge lands in accordance with Alaska state and federal regulations. Moose and caribou hunting are both popular in the refuge.


Koyukuk National Wildlife Refuge is home to a wide variety of birds, mammals, and fish. Thousands of waterfowl, primarily wigeon, pintail, scaup, white-fronted geese, and Canada geese are joined by both trumpeter and tundra swans on the Koyukuk's lush breeding grounds each spring. The refuge streams and lakes also sustain large fish populations including king, silver, and chum salmon that migrate up the Yukon River.

The Three Day Slough area supports about five moose per square mile while the Western Arctic caribou herd, numbering around 500,000 animals, migrates through Koyukuk. The Galena Mountain caribou herd, numbering around 300 animals, lives within the refuge year-round. More than 140 bird species, 30 mammal species, and 14 fish species make their home on refuge lands and waters.


The Koyukuk River drains on the southern side of the Brooks Range before merging into the Yukon River 500 miles later, making it the third largest river in Alaska. Within the refuge, the river is surrounded by oxbow lakes, sloughs, and shallow seasonally flooded basins called grass lakes. This tapestry of rich wetlands combines with lowland boreal forests to support a wide variety of birds.

Also located within the Koyukuk Refuge are the Nogabahara Sand Dunes. These dunes were formed thousands of years ago when sand exposed by receding glaciers was blown up against the Nulato Hills. Today, the active dune area extends across 16,000 acres and contains individual dunes up to 200 feet in height and 300 feet or more in length. Nogabahara Sand Dunes are relatively inaccessible and are a designated wilderness area within the National Wilderness Preservation System.


There are no roads, maintained trails, campgrounds, public use cabins, or visitor facilities within the refuge. River travel is the best way to see the Koyukuk Refuge, including motorized boats, canoes, kayaks, rafts. Backcountry camping is permitted.


The Koyukuk National Wildlife Refuge is located 270 miles west of Fairbanks and access is limited to air and river travel in this roadless part of Alaska. Visitors can access the refuge by air charter operators in Fairbanks and Galena.

 For more information, visit the Koyukuk National Wildlife Refuge website.

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