What You Need To Know About Common Eider
Question
The common eider, also called the St. Cuthbert’s or Cuddy’s duck, is a large sea duck that is common on the northern coasts of Europe, North America, and eastern Siberia.
Often seen swimming into the sea in flocks of up to several thousand birds.
During the breeding season, eiders can also be found, and often nest in colonies.
Eiderdown, known for its insulating properties, is used in large quantities in lining the nests of these ducks, helping to keep the eggs warm in the cold northern climate.
In some places, such as Iceland, eiderdown is harvested commercially at coastal “eider farms,” where wild birds are encouraged to nest in nooks built for them.
*Overview Of The Common Eider*
Eider’s are birds of the cold north with a warm reputation, the common eider is famous for its insulating fluffy qualities (it is usually collected from nests without harming the birds).
Males breed sharply white and black, with a pistachio-green accent on the neck.
Females have a warm brown and black coloration.
These Northern Hemisphere’s largest ducks congregate along rocky ocean shores, diving for mussels and other clams, which they pluck from rocks with long, chisel-like bills.
Males court females with delicate crown calls year-round.
What They Feed On
They feed mostly on mussels, clams, scallops, sea urchins, starfish, and crabs.
Eider’s swallow their prey whole and then crush it with their gizzard. They feed in groups for up to 30 minutes.
After feeding, they rest, get ready to feed, and then feed again throughout the day.
Feeding Habits
Common eider feed by diving into the water to gather food.
This behavior is carried out in a systematic manner, with the leaders diving first and the others following.
Feeding usually lasts only 15-30 minutes per session, after which the common eiders move inland to rest and digest their food.
After recovering their strength, they repeat the behavior; this happens throughout the day.
When winter temperatures drop dramatically, common eiders expend less energy and may stop feeding to conserve energy.
Also, common eiders increase their energy levels during this time, becoming more efficient hunters.
Common Eiders have been shown to dive and collect larger prey during the colder months.
Reproduction
Common eiders are monogamous. During the spring, courtship becomes very intense and lasts even after two common eiders have paired.
This ensures a strong bond between the male and the female.
When courting a female in the spring, male common eiders use a series of loud, eerie calls to attract a female.
These calls resemble a sort of slurred moaning “ow-ee-urr” sound.
Although many common eiders are already paired with a mate by the time they reach the breeding grounds, some do not pair until they get to the islands. Pairs of common eiders do not mate for life.
Female common eiders reach sexual maturity earlier than males. A female may be capable of reproduction when she is around two years of age, whereas a male takes three years to sexually mature.
Adult female and a breeding adult male.
Nesting begins in early summer; common eiders return to breeding islands as soon as the ice begins to melt.
It takes a couple of days for a pair to choose a nesting site and prepare it.
The female common eider plucks down from her own body to line a nest, in which she lays four to five eggs, on average (range 2 to 8).
After the second or third egg is laid, the female begins incubation.
Incubation lasts for about 25 days and is only done by the female. About 50 percent of common eider eggs hatch successfully. Young fledge after 30 to 50 days.
The female Common Eider plucks a nest from her body in which she lays four to five eggs.
After the second or third egg is laid, the female begins incubation.
Incubation lasts about 25 days and is done only by the female.
Unlike most other seabirds, male Common Eiders do little to help raise their young.
In fact, male Common Eiders fly away to join the males after the female begins incubation. The young fledge in about 30 to 50 days.
After mating, protecting the young from predators becomes a top priority for most individuals in the flock.
One of the most prominent behaviors that provide protection from predators is screeching.
Common eiders gather in large groups that distract predators and can help ducks by reducing the gull’s ability to hunt effectively.
By banding together in these large groups, common eiders reduce the area exposed to predators and thus reduce the risk of a gull picking out one individual in the group.
Geographical Range
Common eider populations nest mainly in the coastal high-Arctic regions of Canada and Siberia.
Along the east coast of North America, common eiders breed as far south as Maine, and along the west coast of North America as far south as the Alaskan Peninsula.
In winter, common eiders move south, rarely to Florida on the east coast and sometimes to Washington on the west coast.
However, most common eiders move mostly to Newfoundland and Cape Cod to the east and the Aleutian Islands to the west.
Lifespan
Adult common eiders living in the wild have long lives, often as long as 20 years.
Although common eiders are capable of flying about 60 days after hatching, few young survive that long.
Young are killed by predators, starved, or exposed. If one duckling per pair lives long enough to make a migratory flight in the fall, it’s a good year.
Estimated survival rates among adults per year average from 80-95 percent.
*Awesome Facts*
Common Eiders pluck down feathers from their breast to create a toasty warm nest. For more than 1,000 years people have used precious eiderdown to keep warm—gathering the down from empty nests. In Iceland, some eider “farmers” build small wooden huts for the birds to nest in, mimicking the sheltered natural nest sites the birds often use.
Mother Common Eiders lead their young to water, often accompanied by nonbreeding females that help protect the chicks. Broods come together to form “crèches” of up to 150 ducklings. Once formed, a crèche tends to stay together throughout the brood rearing period, although some of the adult females may leave.
The oldest recorded Common Eider was a male at least 22 years, 7 months old when he was found in eastern Canada.
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