Spectacled Eider

Spectacled eiders occur along the coast of Alaska and easternmost Russia and into the Bering Sea. There are two breeding populations in Alaska and one in Russia. Historically there were more breeding individuals in Alaska but more recently the Russian population is much larger. The United States population is an estimated 3,000–4,000 nesting pairs. The spectacled eider molts at sea anywhere from 2 to 45 kilometers (1.2 to 28.0 mi) from the shore and north of 63°N. Since they are rarely seen outside of their breeding grounds, their wintering grounds in the Bering Sea were not known until recently with the help of satellite telemetry in 1995.

As a diving duck, the spectacled eider forages for food in the water by swimming and diving underwater. It is believed to be able to remain submerged longer than most diving ducks and mostly feeds on mollusks while at sea and aquatic insects, crustaceans, and plant material while on the breeding grounds. Breeding pairs are formed in the wintering grounds before spring migration through male displays and female selection. Once at the nesting sites, females build a nest close to the pond on a raised ridge, called a hummock, that are lined with plant materials and feathery down. Nests may be reused for future years. Females are the sole incubators and caretakers of the eggs and chicks and will lay on average three to six eggs with an olive buff color. The eggs measure 6.8 cm (2.7 in) in length and 4.5 cm (1.8 in) in width. Eggs are incubated for 24 days and chicks leave the nest shortly after hatching to be led to the water by the female. The female protects the chicks but they do find all their own food. Spectacled eiders have a fairly rapid development to be such large birds; it only takes about 53 days or less before they can fly.