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Common Eider
(Somateria mollissima)
: "Eider"
German name(s): "Eiderente"
Size: 50-70 cm; wing span 0.95-1.05 m
Weight: 0.8-3.0 kg
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Physical description |
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Click here for a physical description
Common Eiders are large and heavy ducks. Their
plumage
is known for its superbly insulating down. The
plumage
is dimorphic,
i.e. males
and females
are different.
In addition, males
have different
breeding
and non-breeding
plumages.
Breeding males
are mostly black-and-white, with a black cap, belly, sides and stern,
while the rest is white, except for the sides of the nape, which are
pale-green, and the chest which can be creamy.
Males in eclipse
take on a ragged-looking mottled grey to brownish-grey appearance,
with only some white remaining on the breast and wings.
Females
are barred brownish-grey on head, neck and front, with scalloped
brownish-grey wing coverts.
The irises of both sexes are dark.
The heavy bill is wedge-shaped, greyish to greyish-green, in adults
with a pale tip; legs and feet are grey.
Juveniles
are superficially similar to
females,
but are a bit darker and have a different pattern of scalloping.
They also have off-white supercilia that are not found in
females.
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Taxonomy, classification |
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See Common
Eider at Wikipedia .
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Range, habitat, finding this species |
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Click here for information on habitat
and range
The overall distribution of this species can be assessed, and
specific locations where birds have been spotted can be found,
based on individual sighting reports submitted by birdwatchers to
ebird.org
.
The global distribution of the Common Eider is available
HERE
.
There are six races of Common Eider ducks, which are a partly
migratory, partly sedentary species.
Their overall range extends from far north-western Russia, via
the Scandinavian coastline, around the North Sea, along the
coastlines of all northern Atlantic islands (including Spitsbergen,
Iceland and Greenland) to the coastlines of the northern half of
the North American continent and part of the North-west Canadian
polar islands. The western edge of their range lies in the
Aleutian island chain and far-eastern Siberia, including the
Sakhalin peninsula.
The European race of Common Eiders is nominate race
"mollissima".
They are sedentary along the coastlines of the northern British Isles,
some locations along the German North Sea coastline and the
southern Baltic Sea, and all along the western side of Scandinavia,
from the southern tip in Sweden to beyond the North Cape in Norway.
Around the Baltic Sea (except the South coast), along the Kola
peninsula and coastal far north-western Russia they are summer
breeding migrants.
The winter quarters of the migratory population, apart from a
few isolated sites on the Mediterranean coastline, are located
along the southern Baltic Sea coastline, around Denmark and
via the German and the Benelux coastlines to Normandy. There
is also a wintering population along the coast of southern to
central England.
The Faroe Islands have their own sedentary race, "faroeensis".
Common Eiders are found only in coastal habitats. They breed
near saline or brackish water.
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Sightings |
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Click here for sighting information
Race "mollissima"
M. A. Pears reports spotting Common Eiders, nominate race
"mollissima",
on the Farne Islands, off the North-east coast of England, in April 2014.
M. Eaton found Common Eiders, nominate race
"mollissima",
at Skjervoy, near Tromso, Norway, in June 2018.
M. Thomas reports spotting Common Eiders, nominate race
"mollissima",
at Skagen, Jütland, Denmark, in September 2019.
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Photos |
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Race "mollissima"
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ADULT |
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MALE |
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BREEDING |
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Lateral view of a male Common Eider in breeding
plumage
(photo courtesy of M. Eaton)
[Skjervoy, near Tromso, Norway, June 2018]
Lateral view of a male Common Eider in breeding
plumage
(photo courtesy of M. Eaton)
[Skjervoy, near Tromso, Norway, June 2018]
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NON-BREEDING |
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Resting Common Eider, with two males in non-breeding
plumage
on the left
(photo courtesy of M. Thomas)
[Skagen, Jütland, Denmark, September 2019]
Resting Common Eider; males in non-breeding
plumage
have greyish patches
(photo courtesy of M. Thomas)
[Skagen, Jütland, Denmark, September 2019]
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FEMALE |
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Small group of Common Eider ducks, mostly in breeding
plumage,
with two females at the centre
(photo courtesy of M. Eaton)
[Skjervoy, near Tromso, Norway, June 2018]
Resting Common Eider; females seen from behind show two
characteristic white wing bars
(photo courtesy of M. Thomas)
[Skagen, Jütland, Denmark, September 2019]
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IMMATURE/JUVENILE |
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Frontal view of a juvenile Common Eider duck
(photo courtesy of M. Eaton)
[Skjervoy, near Tromso, Norway, June 2018]
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Breeding information |
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Breeding season: Mar - Jun(?) |
Eggs: 3 - 5 |
Incubation period: 24 - 26 days |
Fledging age: 30 - 50 days |
Common Eiders are colonial breeders that return to the island where
they themselves hatched. They have a single brood per season and
sometimes up to 8 eggs are laid. Females will also nest communally
and share incubation duties. They also form creches with their
ducklings to share tending to their offspring.
Common Eider ducklings are precocial, i.e. they leave the nest as soon
as they are dry after hatching.
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Nest |
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Type: Scrape |
Material: Plant material, down lining |
Height above ground: N/A |
Female Common Eider on its nest; they appear to make use of the presence
of humans by nesting near walking tracks in an attempt to deter nest robbers
(photo courtesy of M. A. Pears)
[Farne Islands, off the North-east coast of England, April 2014]
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Eggs |
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Size: 77 x 51 mm |
Colour: Olive to greenish |
Shape: Ellipsoidal |
Covey of Common Eider ducks arriving for hunting as a collective
(photo courtesy of M. Eaton)
[Skjervoy, near Tromso, Norway, June 2018]
Common Eider ducks forming a pack for collective hunting
(photo courtesy of M. Eaton)
[Skjervoy, near Tromso, Norway, June 2018]
Dorsal view of a departing covey of Common Eider ducks
(photo courtesy of M. Eaton)
[Skjervoy, near Tromso, Norway, June 2018]
These pages are largely based on our own observations and those of our
contributors. The structure of these bird pages is explained HERE. For more salient facts on any bird species
please refer to a field guide.