Included in this region are the Aleutian Islands, extending westward from the Alaskan mainland for 1,100 miles, and the Bering Sea islands including the Pribilofs, St. Matthew, Hall, St. Lawrence, and Little Diomede. The Aleutian chain is volcanic in origin with a maritime climate in which wind is ever present. Vegetation at higher elevations consists of dwarf shrub communities, mainly willow and crowberry. Meadows and marshes of herbs, sedges, and grasses are plentiful and some islands have ericaceous bogs. Sea ice does not extend to the Aleutians and permafrost is generally absent; however, sea ice is an important feature of the Bering Sea. Seabirds are a dominant component of this region's avifauna and several species, the Red-legged Kittiwake, Least Auklet, and Whiskered Auklet, breed only in this region. Southern Hemisphere procellariiforms occur regularly in the offshore waters of the southern Bering Sea and northern Gulf of Alaska during Alaskan summers. The breeding diversity of passerines (mainly Lapland Longspur, Snow Bunting, and Gray-crowned Rosy-Finch), and shorebirds (including Black Oystercatcher, Dunlin, Ruddy Turnstone, and Rock Sandpiper) is low. However, McKay's Bunting, the only endemic Alaskan passerine, is restricted to this area.

ABC-designated Globally Important Bird Areas in this BCR

Alaska Maritime National Wildlife Refuge

Buldir Island (Aleutian Islands)

Chagulak Island (Aleutian Islands)

Gareloi Island (Aleutian Islands)

Kaligagan Island (Aleutian Islands)

Kiska Island (Aleutian Islands)

Pribilof Islands

Segula Island (Aleutian Islands)

St. Lawrence Island

St. Matthew and Hall Islands