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About Common Eiders
Common Eiders (Somateria mollissima) are large sea ducks that breed from Maine north to the Arctic. In winter they form large flocks, often numbering in the thousands! You can often see them in the waters off the Maine coast in late summer. Common Eiders hide their nests in the tall grass and sit motionless for weeks while incubating the eggs. They lay 4-5 eggs in a nest made of down plucked from the body of the female.
Eider down provides superior insulation and softness to quilts, pillows, coats and vests. Eider down used to be very valuable for use in down clothing for humans and was collected from the nests during incubation. Even when the down was taken, the female usually did not abandon the nest. Eider down is no longer collected in Maine, so the birds nest undisturbed. However, In Norway, Iceland and Russia, eider ducks are farmed for their incredibly soft down. Farmers collect the first lining of down from eider nests, after which the female ducks reline their nests before laying their eggs. After 25-30 days of incubation, the chicks hatch and the female leads them off to sea. She often finds other females with chicks and form a group with all the chicks getting to grow and play together. You can learn more about Eiders in Maine at Project Puffin: http://www.audubon.org/bird/puffin/virtual/eider.html The Common Eider Somateria mollissima is the largest duck in the northern hemisphere, easily identified by the male's dramatic pattern of black and white plumage. The Common Eider is a sea duck that frequents coastal headlands, offshore islands, skerries, and shoals, as far north as open water permits. It belongs to the sea duck tribe (Mergini), which contains closely related ducks, all of which use marine habitats to some degree. The King Eider Somateria spectabilis, Spectacled Eider Somateria fischeri, and Common Eider all belong to the same genus, and hybridization is known to occur between Common and King Eiders. Common Eiders average about 1800 g in weight, but this varies considerably with race, sex, and time of year; reported weights range from 850 to 3025 g. Adult males in breeding plumage are white above and black below with a small area of light emerald green on the back and sides of the head. The females are barred greyish to reddish brown and camouflage well in the vegetation of the offshore islands on which they breed. Eiders do not attain full adult plumage until they are three years old and undergo major changes in appearance in the course of a year, so that in any flock of eiders many different plumages can be seen. Habits and habitatsEider ducks are gregarious, traveling and feeding in flocks numbering from tens to thousands. Eiders feed during the day by diving to the bottom in waters from 3 to 20 m deep to take mussels, clams, scallops, sea urchins, starfish, and crabs, which are swallowed whole and crushed in the large gizzard. In winter, when daylight is short, more than half the daytime hours are spent in feeding. Flocks move very synchronously in winter, the ducks at the front of a flock diving first and the rest following sequentially. After 15-30 minutes of intensive feeding, flocks move offshore to rest, preen, and digest the contents of the gullet. The feeding sequence is then repeated. In winter, eider ducks feed in shoal waters off headlands and offshore islands and skerries. At night, they gather in compact flocks, sometimes offshore, at other times in the protection of a headland or cove. Folklore claims that under very cold conditions some eiders move around the outer ring of the compact flock in order to keep the water from freezing. Although this behavior has not been documented by scientists, it is known that in winter when the temperature drops eiders minimize their energy expenditure. They become inactive, stop feeding and, presumably to insulate themselves, gather in groups so dense that individual ducks cannot be counted.
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