Importance to waterfowl
Yukon-Kuskokwim Delta, Bristol Bay lowlands, Kotzebue Sound, Izembek Lagoon, and the Aleutian and Bering Sea Islands are the most important waterfowl areas of this region. The Yukon Delta has an estimated breeding population of 1.3-1.7 million ducks, nearly the entire population of emperor and cackling Canada geese, and nearly 70% of the continental population of black brant (King and Lensink 1971). Density of ducks (1989-91) in subarctic tundra (20.5 pairs/mi2) is lower than encountered in boreal forest (24.5 pairs/mi2) or arctic tundra (33.1 pairs/mi2) regions (Conant and Dau 1991). Dominant breeding species in the Bristol Bay according to U.S. Fish and Wildlife Service (USFWS) surveys include scaup (nearly 130,000), scoter (>75,000), mallard (69,000), green-winged teal (>61,000), northern pintail (>59,000), and American wigeon (>46,000). Dominant species in the Yukon Delta include northern pintail (>362,000), green-winged teal (> 263,000), scaup (>254,000), northern shoveler (>181,000), mallard (>157,000), and tundra swan (>116,000). Dominant species in the Seward Peninsula include northern pintail (>131,000), northern shoveler (>53,000), American wigeon (>41,000), and scaup (>33,000). Dominant species in the Kotzebue Sound include American wigeon (>147,000), northern shoveler (>142,000), northern pintail (>112,000), mallard (nearly 93,000), and scaup (>80,000).
Sea ducks (primarily eiders, long-tailed ducks, and scoters) winter in large assemblages along the Alaska Peninsula, Aleutian, Bering Sea, and Kodiak Islands. Single flocks may reach several 100,000 birds, and several million sea ducks winter in this region. This region, combined with the shore of the Arctic Coastal Plain, is the most important area for sea ducks in North America. More than nine million waterfowl are heavily dependent on Bering Sea habitats during their annual cycle, which accounts for approximately 11% of the continental populations (King and Dau 1981). Six species including cackling Canada goose, emperor goose, and Aleutian Canada goose use these areas exclusively (King and Dau 1981). The 15,720 km2 of intertidal habitat found on the eastern Bering Sea coast is probably not duplicated elsewhere on the continent in an area of comparable size. It is not uncommon to find densities of nesting waterfowl, primarily geese, in excess of 57/km2 in the intertidal habitat of the Yukon Delta (King and Dau 1981). The Aleutian Islands contain habitat for the only North American population of European common teal, and Eurasian wigeon breed in the coastal Yukon Delta.