Long-tailed duck

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Long-tailed duck
male long-tailed duck (Clangula hyemalis)

male long-tailed duck ( Clangula hyemalis )

Systematics
Order : Goose birds (Anseriformes)
Family : Duck birds (Anatidae)
Subfamily : Anatinae
Tribe : Sea Ducks and Sawyers (Mergini)
Genre : Clangula
Type : Long-tailed duck
Scientific name of the  genus
Clangula
Leach , 1819
Scientific name of the  species
Clangula hyemalis
( Linnaeus , 1758)

The long- tailed duck ( Clangula hyemalis ) is a monotypical species that belongs to the family of duck birds (Anatidae). It is the smallest of the diving ducks and belongs to the group of sea ducks . However, it occupies a special position within this group because it differs from the other species both morphologically and anatomically. One of the unusual characteristics of this species, which is widespread in the far north, is that it changes its plumage three times a year.

The long-tailed duck is one of the most numerous ducks in the Arctic fauna and was not considered endangered until recently. About five million long-tailed ducks lived in western Russia and three times as many in the rest of the range. However, especially in Europe, the species has suffered a significant population decline for around two decades and was therefore classified as endangered (vulnerable) by the IUCN for the first time in 2012. It has the northernmost breeding area among all Anatinae . In Europe she is a frequent guest on the Baltic coast during the winter half-year. At migration time, it can be easily observed in the Estonian Matsalu National Park with more than a million individuals. In terms of numbers, it occurs significantly less frequently in the North Sea. Only individual long-tailed ducks appear irregularly in the interior.

features

female
male

Long-tailed ducks are small sea ducks. The drake is about 55 cm tall, the female about 40 cm. The bird weighs 650–850 g. Regardless of the plumage , they have a small round head and a short beak. With a complicated moulting scheme , she changes her dress three times a year: a distinction is made between a winter dress and a summer and autumn dress. This separation into three feather dresses is not always given. Many long-tailed ducks moult their plumage continuously, with the result that two adult same-sex birds are not alike. This continuous change of body plumage can be an adaptation to life in very cold waters, in which a well-insulating plumage has priority. However, the tail and wings are only molted once a year after the breeding season.

The very long, pointed tail is characteristic of the males. In winter plumage, the male's head is white. The area around the eyes is colored gray. A black band runs across the chest. In contrast, in the magnificent dress that the bird wears in early and midsummer, the male's head is black. The gray eye spot is still there. In late summer, however, the head and neck are grayish to white. The beak of many long-tailed ducks is black outside the breeding season.

The females are brown-black all year round, the breast is a bit lighter and looks more gray. In winter plumage, they have a light head with a dark plate that extends from the base of the beak to the nape of the neck. They have a gray-brown ear patch of different sizes, a dark back, a brown chest band and white undersides. In summer the neck and head are blackish brown. The face and neck markings are gray-white. Long-tailed long-tailed ducks resemble the females, but their heads are darker and the dark brown wings have no mirror.

They are able to take off from the ground without making a running start and in the air they can reach speeds of up to 100 km / h with very fast wing flapping. Long-tailed ducks usually fly low and can be recognized by their hasty flight. The wings have no conspicuous wing markings.

voice

Lute of the long-tailed duck

The long-tailed duck's voice is very sonorous and can be heard frequently. At courtship time, the males with their heads thrown far on their backs call gauloik , which is often preceded by a gau-gau . The calls are widely audible.

The natural scientist Robert Sale describes the long-tailed duck's reputation as one of the most melodious of the duck birds. It can be heard especially in the early morning hours and is one of the characteristic sounds of the Arctic. The duck's reputation for excitement is also reflected in the duck's name. In English usage, the duck was sometimes referred to as "Oldsquaw" (old squaw) because it was said to be as talkative as old Inuit women. But it is actually the males who are more willing to call out. The scientific name Clangula hyemalis can be translated as nothing but winter bird .

distribution

Long-tailed ducks live high in the north from the tundra to the pack ice belt and are the most common duck birds there. It is represented in a circumpolar manner: it breeds from Alaska via the Canadian archipelago on the arctic coasts of North America. It is also found on most of the ice-free coasts of Greenland and Iceland. It also breeds from Scandinavia across northern Siberia to the Bering Strait. In southern areas they build their nests in the mountains as long as the temperature does not exceed 2 ° C. It is very cold-resistant and during the winter half-year swarms can be observed swimming between the pack ice. Around 4 million long-tailed ducks overwinter in the Baltic Sea, and around a further million stay around the Aleutian chain off Alaska during the winter months. Other important wintering areas can be found in the southwest of Greenland.

The Asian breeding population winters further north. They only occur in exceptional cases as far as the coast of North Korea. Most long-tailed ducks stay north of Hokkaidō even in winter . As Irrgast tailed ducks, however, were already observed in Turkey, Israel, Jordan, Nepal and India.

Reproduction

Egg, Museum Wiesbaden collection
Long-tailed duck on the nest

The breeding season of the long-tailed duck falls in June and July. It breeds on the fresh waters of the arctic tundra. Their nest is usually found near the water. It is mostly hidden in the vegetation. The clutch consists of five to nine elongated oval eggs. The eggs are yellowish to greenish-gray in color. The incubation period is about 25 days.

food

Immersing male

The long-tailed duck is a very good diver and usually looks for food in a water depth of three to ten meters. But it is able to reach fifty to 60 meters. She is also able to dive right out of flight. It mainly eats shellfish as well as molluscs and fish. It generally eats smaller food than the other northern sea ducks. A certain food competition can exist with the collar duck .

Young birds that have not yet fledged seek their food by swimming in the sea with their heads half submerged. The eyes are under water. They are mainly fed by small insect larvae and crustaceans.

Duration

The long-tailed duck is a widespread breeding bird of the Arctic, Eurasia and America, and the most common duck of the tundra zone. The IUCN classified the long-tailed duck as a Least Concern (not endangered) until 2011 and estimated the total population at 6.2 to 6.8 million sexually mature individuals. In 2012, however, the species was classified as "vulnerable" (endangered) for the first time due to the drastic decline in the number of long-tailed long-tailed ducks in the Baltic region.

The Siberian and Greenland populations are apparently stable. Iceland's population declined for some time due to oil spills and drowning in fishing nets, but has now stabilized.

The decline in the Baltic Sea region is attributed to drowning as bycatch in fishing nets. In coastal waters off Usedom alone, over 60% of 10,000 bycatch victims among waterfowl were long-tailed ducks.

supporting documents

Soaring long-tailed duck

literature

  • Jonathan Alderfer (Ed.): Complete Birds of North America. National Geographic, Washington DC 2006, ISBN 0-7922-4175-4 .
  • Hans-Günther Bauer, Einhard Bezzel and Wolfgang Fiedler (eds.): The compendium of birds in Central Europe: Everything about biology, endangerment and protection. Volume 1: Nonpasseriformes - non-sparrow birds. Aula-Verlag Wiebelsheim, Wiesbaden 2005, ISBN 3-89104-647-2 .
  • John Gooders and Trevor Boyer: Ducks of Britain and the Northern Hemisphere. Dragon's World Ltd, Surrey 1986, ISBN 1-85028-022-3 .
  • Janet Kear (Ed.): Ducks, Geese and Swans. Oxford University Press, 2005, ISBN 0-19-854645-9 .
  • Richard Sale: A Complete Guide to Arctic Wildlife. Christopher Helm Publisher, London 2006, ISBN 0-7136-7039-8 .

Web links

Commons : Long-tailed duck ( Clangula hyemalis )  - Collection of images, videos and audio files

Individual evidence

  1. ↑ Gooders and Boyer, p. 125
  2. ↑ https://apiv3.iucnredlist.org/api/v3/taxonredirect/22680427
  3. ↑ a b c Kear, p. 724
  4. ↑ Bauer et al., P. 128
  5. ↑ Kear, p. 723
  6. ↑ Hans-Heiner Bergmann; Hans-Wolfgang Helb; Sabine Baumann; The voices of the birds of Europe - 474 bird portraits with 914 calls and chants on 2,200 sonograms , Aula-Verlag, Wiesbaden 2008, ISBN 978-3-89104-710-1 , p. 68
  7. ↑ Sale, p. 125
  8. ↑ Sale, p. 124
  9. ↑ a b Kear, p. 725
  10. ↑ BirdLife factsheet on the long-tailed duck , accessed on March 17, 2013
  11. ↑ Thomas Heinicke, Kathrin Heinicke: By-catches in the Baltic Sea fisheries endanger the resting and wintering populations of the long-tailed duck and other sea birds in Germany . Seevögel, Volume 38, 2017, pp. 4-11