Courtesy Kenn Kaufman
The Spectacled Eider breeds in Western Alaska on the Yukon-Kuskokwim Delta and along the northern Alaskan coast from Wainwright eastward to Camden Bay. In Siberia, this sea duck also breeds around the deltas of the Yena, Indigirka, and Kolyma rivers. Critical molting areas include Alaska's Ledyard Bay and Norton Sound. The Spectacled Eider winters in the Bering Sea, south of St. Lawrence Island.
Close to the coast and always near water, Spectacled Eiders breed on Arctic tundra and use small islands, shorelines, peninsulas, and drier spots in wet meadows for their nest sites. Here, thick sedges and grasses are important components for nesting. These sea ducks molt in shallow waters near the shore, but then congregate in the Bering Sea for winter, often on pack ice with openings, over waters as deep as 200 feet.
On its breeding grounds, the Spectacled Eider consumes insects such as flies, midges, beetles, and their larvae; crustaceans including amphipods, fairy shrimp, tadpole shrimp, and snails; and various plants such as pond weed seeds, crowberries, and moss. While foraging, these birds dabble, dive, and glean items from the surface. During molting and while wintering, they dive for snails, clams, mussels, amphipods, crabs, sand dollars, sea stars, and fish like sculpin and small cod.
Pairs of Spectacled Eiders appear to form at sea in late winter. Monogamous pairs probably maintain bonds with behaviors similar to other eider ducks, like ceremonial stretching and head tossing. Arriving on the breeding grounds from mid-May to early June, paired females select a site and build a nest, at which time males chase off rivals. A bowl shape is pressed into the damp tundra, lined with grasses and sedges, and then filled with one to 11 olive eggs. Insulated with down that the female pulls from her own chest, and incubated by the female alone for 90% of the day, the eggs hatch in about 24 days. The brownish, downy chicks already show the spectacled pattern and can walk, preen, and swim in about a day.
Spectacled Eider chicks grow at an amazing pace, reaching adult size in two months—testament to the fertility of the Arctic tundra. The young eiders first fly in about 50 days and probably spend the next two to three years at sea, before returning to breed.
Completing a full but short migration, Spectacled Eider initially travel in flocks of six to 80, then form super flocks with other eider ducks to stage, molt, and rest. Throughout June, males leave their breeding areas, followed by females and immature birds in late August. All Spectacled Eiders stop in mid-route to molt during the fall. Throughout October, weather and food abundance affect their departure for the wintering grounds. The condition of the sea ice dictates spring migration, and most Spectacled Eiders arrive on the breeding grounds from May to early June.