Kagalaska Island, Aleutian Islands, Alaska, USA Photograph by Rear Admiral Harley D. Nygren, NOAA corps (ret.)   Northwestern North America: Aleutian Islands in western United States (Alaska) Tundra   2,100 square miles (5,500 square kilometers) -- slightly bigger than Delaware Relatively Stable/Intact

· Icy Island Chain
· Special Features
· Did You Know?
· Wild Side
· Cause for Concern
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Icy Island Chain

Stretching nearly more than 900 miles (1,500 kilometers) southwest of the Alaskan peninsula between the Bering Sea and the Gulf of Alaska are the Aleutian Islands. These islands, formed by volcanoes over many thousands of years, range in elevation from sea level to over 6,200 feet (1,900 m). The highest points are bare rock and basaltic rubble. Despite the harsh environment, this ecoregion supports many seabird colonies of extraordinary size and global importance. For example, the Pribilof Islands provide breeding habitat for about three million seabirds.

Special Features

Many of the Aleutian Islands support plants and animals found nowhere else in the world, such as the Pribilof Islands shrew and the Aleutian shield fern, the only federally listed endangered plant in Alaska.

	The Pribilof Islands are home to virtually all of the world's 250,000 red-legged kittiwakes. These gulls are distinguished by their bright red feet and legs.

Wild Side

At high elevations, dwarf shrub, willow, and crowberry grow. Lower, more sheltered and coastal areas support meadows dominated by bluejoint and other plants. Bogs contain low-growing plants that, over many years, have formed thick deposits of peat.

Cause for Concern

The Aleutian Islands are largely intact, but many kinds of human activity have affected both the plants and animals of this ecoregion. Several animal species introduced for ranching have escaped and are now feral, including cattle, caribou, and foxes. These animals are a threat because they overgraze certain native plants or kill too many native animals, such as birds and their eggs. Introduced rats can cause great damage to colonies of birds. Pollution is severe in certain areas, mostly from active and inactive military bases. Nuclear testing occurred on Amchitka Island in 1971, and the resulting radioactivity is still present in the ecosystem. Most dramatic is the decline of almost all species of fish-eating seabirds, probably as a result of commercial fishing, which has caused a drastic drop in available food.

For more information on this ecoregion, go to the World Wildlife Fund Scientific Report.