NATURAL HISTORY

SPECTACLED EIDER } Somateria fischeri
FAMILY: Anatidae

DESCRIPTION: When in breeding plumage, adult males boast black chests, white backs, orange bills, and pale green heads. Their white eye patches are encircled by black feathers, giving the appearance of spectacles. During late summer and fall, males are mottled brown. Females and juveniles are this color year-round, with pale brown eye patches and blue-gray bills. Both sexes have bright yellow feet. The spectacled eider weighs about three pounds and has a wingspan of 36 inches.

HABITAT: Spectacled eiders spend winter months gathered in dense flocks far offshore, where waters reach depths of more than 200 feet. During mating season, these birds prefer coastal tundra areas near shores, lakes, deltas, and tidal inlets.

RANGE: Spectacled eiders are found in three main breeding populations in Alaska and northeast Russia: the Yukon-Kuskokwim Delta, Alaska’s North Slope, and eastern coastal Russia.

MIGRATION: Flocks of spectacled eiders winter in the Bering Sea.

BREEDING: Female spectacled eiders initiate nest-building using available vegetation and their own down feathers. Nests are established near shallow ponds or lakes, usually within 10 feet of water. Soon after eggs are laid, males leave the nesting grounds for offshore molting areas. A typical clutch consists of four to five olive-green eggs, incubation lasts about 24 days, and young can feed themselves within days of hatching. Young fledge after approximately seven weeks.

LIFE CYCLE: The spectacled eider has a lifespan up to 15 years.

FEEDING: These ducks are omnivorous, feeding mostly on mollusks, crustaceans, aquatic insects, and vegetation. During the breeding season, spectacled eiders feed like dabbling ducks, immersing their heads below the water’s surface. In the winter, they dive deep, capturing bottom-dwelling food sources such as clams.

THREATS: Significant threats to spectacled eiders include: oil and gas drilling, and the accompanying development of coastal sites; increased predation on the eiders’ breeding grounds; commercial bottom-trawl fisheries; global warming; and lead poisoning, caused by consumption of spent lead shot. A variety of pollutants have also been found in spectacled eiders’ blood, feathers, and eggs, including arsenic, barium, cadmium, mercury, and selenium.

POPULATION TREND: Since the 1970s, the breeding population on the Yukon-Kuskokwim Delta has declined by 96 percent — no more than 4,000 pairs nest there today. Historical records for other nesting areas are scarce, but recent observations suggest populations have also declined on the North Slope. Biologists estimate that 9,000 pairs currently nest on Alaska’s arctic coastal plain and at least 40,000 pairs nest in Russia.

Spectacled eider photo by Olaf Oliviero Riemer, BY-SA