Common eider
The common eider, also known as St. Cuthbert's duck or Cuddy's duck, is the largest member of the genus Somateria and inhabits the colder regions of the Northern Hemisphere. Renowned for its remarkable diving capabilities, this duck spends most of its life on the frigid, turbulent seas of the Arctic, showcasing a versatile plumage that provides insulation and is prized for its soft down feathers. Historically, these feathers have been harvested sustainably for use in warm clothing and bedding, an activity that dates back centuries to when the first bird sanctuary was established to protect eiders on the Farne Islands.
Common eiders exhibit sexual dimorphism, with males sporting more vibrant plumage to attract mates, while females possess camouflaging brown feathers. These birds are social but territorial during breeding season, nesting onshore near the tide line. The female incubates her eggs and, shortly after hatching, leads her chicks to water where they quickly learn to dive and forage. Despite their resilience to harsh environments, common eiders face threats from oil pollution and human interference, leading to their classification as a near-threatened species. Their fascinating behavioral patterns and ecological significance make them a subject of interest for conservationists and bird enthusiasts alike.
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Common eider
The common eider is referred to by different names, including St. Cuthbert's duck and Cuddy's duck. Eiders are the largest members of the genus Somateria. They exist solely in the cold regions of the Northern Hemisphere. The species is also notable for its excellent diving abilities and because it spends nearly its entire life on the cold, icy, stormy seas near the Arctic. The plumage on the eider is versatile. It keeps eiders warm and dry. It is also used to make quilts and clothing.
Kingdom: Animalia
Phylum: Chordata
Class: Aves
Order: Anseriformes
Family: Anatidae
Genus: Somateria
Species: Mollissima
Eiders have been popular with people for centuries. It is believed that the first bird sanctuary to protect birds was constructed for eiders in the seventh century. Saint Cuthbert, a hermit, protected eiders on the Farne Islands off the northeast coast of Great Britain. The sanctuary still exists today. Inhabitants in cold regions have historically collected the soft downy feathers of the eiders, as clothing and blankets made from these materials can be warmer than most people-made items. Harvesting eider feathers, called eiderdown, does not require harming or killing the birds. Scandinavian eider farmers provide nesting places for the birds with ribbons, wind chimes, and mirrors. Each eider provides enough down to line two nests each year. A typical sleeping bag or quilt requires the down from 100 nests.
Common eiders are 20 to 28 inches (50 to 71 centimeters) long and weigh up to 6.5 pounds (just over 3 kilograms). From one tip to the other, their wings average 31.5 to 43.5 inches (80 and 110 centimeters). Males are dimorphic, which means their coloring is more vivid. This helps them attract females and to discourage male competitors. Female eiders, or ducks, have brown plumage in various patterns with white markings on their wings. This is more suitable for camouflage. Male eiders, or drakes, have black caps on their heads and black undersides. Their upper back, forward wing edges, throats, and necks are white. Other distinct markings include pale green patches on their necks and light-yellow feathers on their breasts.
Eiders maintain habitats in the northern Pacific, Atlantic, and Arctic Oceans. Flocks of common eiders live year-long on the water. These hardy birds can withstand harsh, cold conditions. They migrate south to unfrozen waters as the Arctic freezes, but these waters are still very cold. The ducks may roost on the sea in a storm or on wet rocks. They also inhabit sheltered fjords and estuaries.
Eiders are exceptional at flying and can reach speeds up to forty miles per hour (sixty-four kilometers per hour). In these harsh habitats, the eiders dive for shellfish, such as whelks, cockles, mussels, and crabs. Powerful bills enable them to crush the shells with no difficulty. Diving to depths of thirty to fifty feet (ten to fifteen meters), they can stay underwater for an average of 30 seconds but may also resurface after one minute.
Common eiders only have one mate, which makes them monogamous. Male and female partners can communicate with each other with loud calls. They do not mate for life but for a season. After mating, the male and female eider find a nesting site onshore near the line of the tide. Possible sites are among rocks and driftwood or in woods and moorland. Although they are social birds during the rest of the year, the eiders are territorial of their nesting sites during the breeding season in May and June. Within the breeding colony, the birds fight for the best nesting sites. A nest of grass and seaweed built by the female and lined with down from her breast provides a warm bed for the eggs. The male leaves the female after mating so that he may molt, or shed, his feathers. She incubates her four to five eggs for twenty-one to twenty-four days, keeping them warm with her body. The female's brown plumage camouflages her from predators, like rats and foxes, as she sits still and quietly on the nest. The chicks follow their mother to the water within hours of hatching. They learn to swim and dive for food. Predators, such as skuas, eat more than half of the young each year before they reach the water. The young birds' feathers are fully developed after seventy days. They are able to mate after two to three years.
The lifespan of the common eider is up to twenty years. The greatest threat to common eiders is oil pollution along the coasts. Human interference and loss of eggs is another threat to common eiders. These threats have made the common eider a near-threatened species.
Related species:
- King Eider (Somateria spectabilis)
- Steller’s Eider(Polysticta stelleri)
- Spectacled Eider(Somateria fischeri)
Bibliography
“Common Eider.” Animalia.bio, animalia.bio/common-eider. Accessed 19 Aug. 2024.
“Eider.” A-Z Animals, 27 May 2024, a-z-animals.com/animals/eider. Accessed 19 Aug. 2024.
Rogers, Curtis. “Somateria Mollissima Common Eider.” Animal Diversity Web, 2002, animaldiversity.org/accounts/Somateria‗mollissima. Accessed 19 Aug. 2024.