Nature Notes: Common Eider
Eiders nest in colder climates across North America, Europe and Siberia, but Maine has approximately 28,000 breeding pairs, according to the National Audubon Society. They nest on the tundra or in Maine on rocky ledges and islands, often returning to the same nest site annually. Nests will have several eggs and a lining of that famed eider down, plucked from the female’s breast. I can always tell when eiders are back in our cove for the spring nesting season. The birds have a pleasant “ah-ooo” sound, but when your back is to the water it sounds like someone moaning or cooing along the shore.
The ducklings leave the nest within a day of hatching and are capable of swimming and feeding on their own. The diet of eiders is another distinguishing feature, since they feed primarily on crustaceans and mollusks, with periwinkles, mussels and clams being their favorites. Mollusks are swallowed whole, and the shells are broken up in the duck’s gizzard.
Eiders are ungainly on land, since like most diving ducks, their legs are set well back on their body. But in the water they are strong swimmers, capable of staying submerged over 1 minute and diving below 100 feet. Eiders also excel in the air. Those powerful wings can propel an eider at speeds up to 70 mph!
Large die-offs knocked down eider populations in the 1990’s due to changes in Arctic ice movements but today their population is robust at 1.5-2 million in North America. So, bundle up this winter and walk a rocky shore and you are sure to see these distinctive ducks foraging along Harpswell’s coastline.
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