The diet of common eiders consists almost exclusively of mollusks, echinoderms, crustaceans, and a few fish. Common eiders swallow their prey whole and then crush them with their gizzard. During the winter months, daylight is short-lived and so common eiders spend more than half of the day feeding.
Common eiders feed by diving into the water to collect food. This behavior is done in a systematic fashion, with the leaders diving first and the rest following behind. Feeding usually only lasts 15 to 30 minutes per session and afterwards the common eiders move inland to rest and digest their food. After regaining strength, they repeat the behavior; this occurs throughout the day. When temperatures drop drastically during the winter, common eiders expend less energy and may stop feeding to conserve energy. Also during this time, common eiders improve their energy levels by becoming more effective hunters. It has been shown that during the cold months, common eiders dive and collect larger prey.
Foods eaten include: mussels, clams, scallops, sea urchins, starfish, crabs and fish.
Animal Foods: fish; mollusks; aquatic crustaceans; echinoderms
Primary Diet: carnivore (Piscivore , Eats non-insect arthropods, Molluscivore , Eats other marine invertebrates)
The primary predators of common eiders are Arctic foxes (Vulpes lagopus) and various gulls (family Laridae). The gulls are perhaps more of a threat than the foxes. This is because common eiders tend to nest on islands, which don’t have land predators, but gulls can fly out to the islands with no trouble. Gulls prey on the eggs and the young of common eiders, and are a major threat to the survival of the young. The threat posed by the gulls is alleviated somewhat by the creching behavior of common eiders. Gulls do, however, still prey on common eiders even during creching. Gulls will follow the flock in flight and make various swoops into the crowd to try and snag a young duckling. Similarly, while on the ground, gulls will work together. One gull will hover over a common eider who is concealing her young next to her body causing the female to jump up and attack the gull. In doing this, the female exposes her young, allowing a gull on the ground to snatch it away.
Known Predators:
Measuring, on average, between 53 to 60 cm (21 to 24 inches) common eiders are the largest ducks in the northern hemisphere. Although the weight of common eiders differs depending upon the individual’s sex and the time of year, they average about 1800 grams, with reported measurements being between 850 and 3025 grams.
Adult male common eiders are recognizable by their dramatic arrangement of black and white plumage. They are black on their underside and white on their back and forewings. The male common eider also has a predominantly white head, but it is crowned with black and they have a touch of light emerald green on the back and sides of their head. The adult female common eider is almost exclusively brownish or reddish-brown and is closely barred. Immature males begin their life grayish-brown in color, then become dusky with a white collar and eventually end up like their mature counterparts. The white plumage in adult males develops in irregular patterns.
Female Common Eiders blend in well with their environment, which is the vegetation on the offshore islands. Adult plumage patterns are not fully complete until they reach about three years of age. In the period of a single year, dramatic differences in the appearance of plumage occur, which is why there is a great diversity in appearance among individuals in any given flock.
Range mass: 850 to 3025 g.
Average mass: 1800 g.
Range length: 53 to 60 cm.
Sexual Dimorphism: sexes colored or patterned differently
Other Physical Features: endothermic ; bilateral symmetry
Although common eiders are capable of flight about 60 days after hatching, few young ever survive that long. Young are killed by predators, starvation, or exposure. If one duckling per couple lives long enough to make the migration flight in the fall, it is a good year. Even though this survival rate seems low, adult common eiders living in the wild have long lives, often as long as 20 years. Estimated survival rates among adults per year average from 80-95 percent.
Range lifespan
Status: wild: 20 (high) years.
Average lifespan
Status: wild: 271 months.
Common eiders nest mainly among the rocks surrounding the coastlines and in tundra, particularly on small offshore islands that are free of mammalian predators. Nests are often hidden in tall grasses to avoid predation.
Habitat Regions: temperate ; polar ; terrestrial
Terrestrial Biomes: tundra
Aquatic Biomes: coastal
Common eider populations nest mainly in the coastal high arctic regions of Canada and Siberia. Along the eastern coast of North America, common eiders breed as far south as Maine, and along the western coast of North America they breed as far south as the Alaskan Peninsula. During the winter, common eiders move south, rarely as far as Florida on the east coast and sometimes as far south as Washington on the west coast. Most common eiders, however, move primarily to Newfoundland and Cape Cod in the east and to the Aleutian Islands in the west.
Biogeographic Regions: nearctic (Native ); palearctic (Native )
Other Geographic Terms: holarctic
Common eiders have an impact on the prey they eat; they are also an important food source for their predators.
Common eiders are widely known for their down feathers. Although they are also valued as a sport duck and for culinary purposes, their feathers have produced a multi-million dollar industry in some parts of the world. Common eider down can be collected from nests without disturbing the eggs or the well-being of the duck.
Positive Impacts: food ; body parts are source of valuable material
There are no known adverse affects of common eiders on humans.
Common eider populations were dramatically reduced prior to hunting regulations in North America. Some places in Canada and the arctic north even saw local extinctions of common eiders. Since the hunting laws were enacted, these areas have been recolonized by common eiders; they have even extended their breeding ranges. Common eiders are protected under the US Migratory Bird Treaty Act.
US Migratory Bird Act: protected
US Federal List: no special status
CITES: no special status
State of Michigan List: no special status
IUCN Red List of Threatened Species: least concern
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.
Communication Channels: acoustic
Perception Channels: visual ; tactile ; acoustic ; chemical
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.
Mating System: monogamous
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.
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.
Breeding season: summer
Range eggs per season: 2 to 8.
Average eggs per season: 4.
Average time to hatching: 25 days.
Range fledging age: 30 to 50 days.
Range age at sexual or reproductive maturity (female): 2 to 3 years.
Average age at sexual or reproductive maturity (female): 3 years.
Range age at sexual or reproductive maturity (male): 2 to 3 years.
Average age at sexual or reproductive maturity (male): 3 years.
Key Reproductive Features: iteroparous ; seasonal breeding ; gonochoric/gonochoristic/dioecious (sexes separate); sexual ; oviparous
Average time to hatching: 28 days.
Average eggs per season: 4.
The female common eider plucks down from her own body to line a nest, in which she lays four to five eggs. 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. Unlike most other seabirds, male common eiders do very little in raising the young. In fact, male common eiders leave to join male flocks once the female has begun incubation. Young fledge in about 30 to 50 days.
After mating, protecting the young from predators becomes one of the major priorities among most individuals in a flock. One of the most noticeable behaviors to provide protection from predators is creching behavior. Common eiders gather into large groups which distract predators and may help ducklings by reducing the gull’s ability to hunt effectively. By pooling into these large groups, common eiders reduce the area exposed to the predators and thus reduce the risk of a gull picking out a single individual in the group.
Parental Investment: no parental involvement; precocial ; pre-hatching/birth (Protecting: Female); pre-weaning/fledging (Provisioning: Female)
The common eider (pronounced /ˈaɪ.dər/) (Somateria mollissima), also called St. Cuthbert's duck or Cuddy's duck, is a large (50–71 cm (20–28 in) in body length) sea-duck that is distributed over the northern coasts of Europe, North America and eastern Siberia. It breeds in Arctic and some northern temperate regions, but winters somewhat farther south in temperate zones, when it can form large flocks on coastal waters. It can fly at speeds up to 113 km/h (70 mph).[2]
The eider's nest is built close to the sea and is lined with eiderdown, plucked from the female's breast. This soft and warm lining has long been harvested for filling pillows and quilts, but in more recent years has been largely replaced by down from domestic farm-geese and synthetic alternatives. Although eiderdown pillows or quilts are now a rarity, eiderdown harvesting continues and is sustainable, as it can be done after the ducklings leave the nest with no harm to the birds.
The common eider was formally named by the Swedish naturalist Carl Linnaeus in 1758 in the tenth edition of his Systema Naturae. He placed it with all the other ducks in the genus Anas and coined the binomial name Anas mollissima.[3] It is now placed with two other species in the genus Somateria that was introduced in 1819 by the English zoologist William Leach.[4][5] The genus name is derived from Ancient Greek σῶμα sōma 'body' (stem somat-) and ἔριον erion 'wool'. The specific mollissimus is Latin, meaning 'very soft'. Both parts of the name refer to its down feathers.[6]
Six subspecies are recognised:[5]
The common eider is both the largest of the four eider species and the largest duck found in Europe, and is exceeded in North America only by smatterings of the Muscovy duck, which only reaches North America in a wild state in southernmost Texas (and arguably south Florida where feral but non-native populations reside). It measures 50 to 71 cm (19+1⁄2 to 28 in) in length, weighs 0.81 to 3.04 kg (1 lb 12+1⁄2 oz to 6 lb 11 oz) and spans 80–110 cm (31–43 in) across the wings.[7][8] The average weight of 22 males in the North Atlantic was 2.21 kg (4 lb 14 oz) while 32 females weighed an average of 1.92 kg (4 lb 3+1⁄2 oz).[9] It is characterized by its bulky shape and large, wedge-shaped bill. The male is unmistakable, with its black and white plumage and green nape. The female is a brown bird, but can still be readily distinguished from all ducks, except other eider species, on the basis of size and head shape. The drake's display call is a strange almost human-like "ah-ooo", while the hen utters hoarse quacks. The species is often readily approachable.
Drakes of the European, eastern North American and Asia/western North American races can be distinguished by minor differences in plumage and bill colour. Some authorities place the subspecies v-nigra as a separate species.
This species dives for crustaceans and molluscs, with mussels being a favoured food. The eider will eat mussels by swallowing them whole; the shells are then crushed in their gizzard and excreted. When eating a crab, the eider will remove all of its claws and legs, and then eat the body in a similar fashion.
It is abundant, with populations of about 1.5–2 million birds in both North America and Europe, and also large but unknown numbers in eastern Siberia (HBW).
A particularly famous colony of eiders lives on the Farne Islands in Northumberland, England. These birds were the subject of one of the first ever bird protection laws, established by Saint Cuthbert in the year 676.[10] About 1,000 pairs still nest there every year. Because St. Cuthbert is the patron saint of Northumberland, it was natural that the eider should be chosen as the county's emblem bird; the birds are still often called Cuddy's ducks in the area, "Cuddy" being the familiar form of "Cuthbert".
In Canada's Hudson Bay, important eider die-offs were observed in the 1990s by local populations due to quickly changing ice flow patterns. The Canadian Wildlife Service has spent several years gathering up-to-date information on their populations, and preliminary results seem to show a population recovery.[11][12][13] The common eider is the object of the 2011 documentary People of a Feather,[14] which studies the historical relationship between the Sanikiluaq community and eiders, as well as various aspects of their ecology.[15]
The common eider is one of the species to which the Agreement on the Conservation of African-Eurasian Migratory Waterbirds (AEWA) applies.
Eiders are colonial breeders. They nest on coastal islands in colonies ranging in size of less than 100 to upwards of 15,000 individuals.[16] Female eiders frequently exhibit a high degree of natal philopatry, where they return to breed on the same island where they were hatched. This can lead to a high degree of relatedness between individuals nesting on the same island, as well as the development of kin-based female social structures.[17] This relatedness has likely played a role in the evolution of co-operative breeding behaviours amongst eiders. Examples of these behaviours include laying eggs in the nests of related individuals[18] and crèching, where female eiders team up and share the work of rearing ducklings.[19]
Common eider composite
_male,_London_Wetland_Centre_-_Diliff.jpg)
Adult drake
Adult male left, female right
Adult male in eclipse plumage
Male juvenile in first winter plumage, similar but different from eclipse plumage
Female
.png)
Female
_in_flight.jpg)
Male in flight
Eider duck skin coat
Traditional man-made eider nesting boxes
Eider nest on the tundra in the Canadian Arctic
Small eider creche: three adult females over six ducklings at Biddeford Pool, ME.
_male_eclipse_plumage_stretching_composite.jpg){kind=small}
stretching
_on_the_dune,_Heligoland.jpg)
Common eider (female) on the dune, Heligoland
_on_the_dune,_Heligoland.jpg)
Common eider (male) on the dune, Heligoland
.jpg)
Common eider with ducklings swimming
_-_Ystad-2016.jpg){kind=small}
Common eider flying by.
Common eider flying by. The common eider (pronounced /ˈaɪ.dər/) (Somateria mollissima), also called St. Cuthbert's duck or Cuddy's duck, is a large (50–71 cm (20–28 in) in body length) sea-duck that is distributed over the northern coasts of Europe, North America and eastern Siberia. It breeds in Arctic and some northern temperate regions, but winters somewhat farther south in temperate zones, when it can form large flocks on coastal waters. It can fly at speeds up to 113 km/h (70 mph).
The eider's nest is built close to the sea and is lined with eiderdown, plucked from the female's breast. This soft and warm lining has long been harvested for filling pillows and quilts, but in more recent years has been largely replaced by down from domestic farm-geese and synthetic alternatives. Although eiderdown pillows or quilts are now a rarity, eiderdown harvesting continues and is sustainable, as it can be done after the ducklings leave the nest with no harm to the birds.
_skull_at_the_Royal_Veterinary_College_anatomy_museum.JPG)
