Yukon Flats National Wildlife Refuge

Yukon Flats is the third largest wildlife refuge in the United States, encompassing approximately 11.1 million acres of land (8.63 million acres in federal ownership). Extending 220 miles east-west along the Arctic Circle, the refuge lies between the Brooks Mountain Range to the north and the jagged limestone peaks of the White Mountains to the south. The Trans-Alaska Pipeline corridor runs along the refuge’s western boundary while the eastern boundary extends to within 30 miles of the Canadian border. The Yukon River flows through refuge lands, sculpting the vast floodplain of lakes, ponds, and streams that dominate the landscape.

Tens of thousands of lakes and ponds spot the Yukon Flats Refuge, mostly concentrated in the floodplains along the Yukon River and some of its tributaries. The surrounding uplands, where there are fewer lakes, serve as important drainage systems from the bordering mountains, hills, and highlands. 

The abundance of water in lakes, ponds, and streams provides important habitat for waterfowl from all four North American flyways. The refuge hosts as many as two million ducks annually and supports the highest breeding densities in Alaska. Alaska's only endemic fish, the Bering Cisco, spawns in the flats as well.