NATURAL HISTORY

STELLER'S EIDER } Polysticta stelleri
FAMILY: Anatidae

DESCRIPTION: The Steller's eider weighs less than two pounds and has an average wingspan of 29 inches. Males in breeding plumage have a black back, yellow-buff underside, and white head. They have a green bump on the back of their heads and a round black spot on the side of their breasts. For a short time in the fall, males become a mottled brown with a blue patch on the wing, appearing similar to females and juveniles. Both sexes have a gray, unfeathered bill, blue-gray feet, and a long tail.

HABITAT: Steller's eiders spend most of the year in shallow, near-shore marine waters. Molting and wintering flocks gather in lagoons and bays, as well as along rocky headlands and islets. Nesting occurs on tundra adjacent to small ponds, often near the coast but sometimes ranging 50 miles inland.

RANGE: Two breeding populations of Steller's eiders are in arctic Russia, and one is in Alaska. The Alaskan breeding population nests primarily on the arctic coastal plain, although a very small group remains on the Yukon-Kuskokwim Delta.

MIGRATION: Steller's eiders winter in the Bering Sea.

BREEDING: The nests made by Steller's eiders, constructed in small ponds near the coastline, are put together using available vegetation and are lined with a thick bed of down that is shed during egg laying. Females incubate between six and 10 eggs for about 25 days, without eating during the entire period. Young hatch in late June, and shortly thereafter, ducklings are led by their mothers to feed on aquatic insects and plants. The ducklings are capable of flight after five or six weeks.

LIFE CYCLE: Steller's eiders live an estimated 20 to 25 years.

FEEDING: Steller's eiders are diving ducks that feed primarily on mollusks and crustaceans. They are known to eat aquatic plants and insects, as well as crowberries, a staple tundra fruit preferred by several kinds of waterfowl.

THREATS: Some likely contributing factors to the worldwide decline of the Steller's eider are oil and gas drilling, human-caused increases in predator populations, lead poisoning, habitat degradation, and global warming.

POPULATION TREND: As recently as the 1960s, Steller's eiders may have numbered 500,000 worldwide. The current population is believed to be between 150,000 and 200,000, with the majority of these birds nesting in Russia. Estimates indicate that as few as 200 breeding pairs of Steller's eiders remain in Alaska.

Stellers eider photo by Ron Knight