Koyukuk National Wildlife Refuge
Alaska Region   

Icon of Blue Goose Compass. Click on the compass to view a map of the refuge (pdf)



Nogahabara Sand Dunes
Koyukuk Wilderness Area
Nogabahara Sand Dunes.  USFWS.One needs only to step to the top of a 50-foot high dune within the 400,000 acre Koyukuk Wilderness to recognize the uniqueness of the Nogahabara Sand Dunes. This active dune area contains about 16,000 acres and is only a small part of a Pleistocene dune field that is now mostly inactive. The individual dunes have been recorded to be 50 to 200 feet high and 300 feet or more in length. The dunes are wind-blown deposits of sand that originated in glaciated areas to the northwest and were deposited in the periglacial Koyukuk area.

Although sparsely vegetated, the active dune field contains a unique assemblage of plant species growing mainly in the sheltered basins between ridges. Present with more common boreal species (such as white spruce, dwarf birch, alder, blueberry and crowberry) are some unusual willows, grasses, sedges and herbs. It is theorized that portions of this plant community are relics of the last ice age, when interior Alaska was a glacier-free shrub-steppe ecosystem.

This unique and fragile ecosystem is protected by the dune fields' relative inaccessability, and its designation as a Wilderness Area within the National Wilderness Preservation System. You can find out more about the Koyukuk and other Wilderness Areas in the United States at

Last updated: April 4, 2010