Pochard

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Pochard
Pochard ♂ (Aythya ferina)

Pochard ♂ ( Aythya ferina )

Systematics
Order : Goose birds (Anseriformes)
Family : Duck birds (Anatidae)
Subfamily : Anatinae
Tribe : Diving ducks (aythyini)
Genre : Aythya
Type : Pochard
Scientific name
Aythya ferina
( Linnaeus , 1758)
Pochard drake, front view
Female pochard

The pochard ( Aythya ferina ) is a species of bird from the family of ducks (Anatidae) and here belongs to the subfamily of ducks ( Anatinae ). It is a sturdy diving duck that is slightly smaller than a mallard . The pochard is primarily a breeding bird of the temperate climate zone of the Palearctic. It is a breeding and annual bird in large parts of Central Europe. However, it also breeds in the Mediterranean area as well as on the salty and brackish waters in steppe and desert zones.

The name common in the German language pochard is a reference to the meat of this duck bird, which is considered tasty. The scientific term chosen by Carl von Linné also points to this: The Latin term ferina , which in the genus Aythya denotes the pochard, is translated for venison .

Appearance

Adult pochard appearance

As a typical diving duck, the pochard is medium-sized, has a short tail and strong legs that are attached to the rear third of the body. When swimming, the species lies deep in the water. In the magnificent plumage the male shows a chestnut brown head and neck, a black breast, a light gray feathered trunk and a black feathered rump. The black color of the beak is interrupted by a gray-blue cross tie. The iris is dark red in color. The plain dress is similar to the splendid dress, but the black plumage on the chest and rump is replaced by a washed-out gray.

The female pochard are much more inconspicuous in color than the males, their head is gray-brown all year round, behind the eye and at the base of the beak there are light, in individual cases almost white colored areas. In contrast, the region under the eye is slightly darker feathered. The color of the breast is dark gray or light brown; overall, the color intensity can differ greatly from one individual to another. The rump of the females is colored light gray like that of the male, but always looks a bit dirty due to the scattered light brown feathers. The rump is dark gray. In winter, the female pochard's beak also has a gray-blue band, but this may be missing. During the breeding season, the beak is always completely black. The iris is brown. The simple dress of the females differs from the magnificent dress only in that the breast and rump are a little more brown feathered than in the magnificent plumage.

Appearance of the chicks and fledglings

The downy dress of the pochard chicks is brown on top with a slight greenish tinge. They resemble the chicks of the red-crested pochard , but are brown on the forehead and top and have a lighter, creamy yellow underside. The sides of the head, front neck and chest are also creamy yellow. An indistinct, only diffusely demarcated light brown eye stripe runs on the face, which begins under the eye. Pochard chicks also have a greenish-yellow wing band and greenish-yellow spots on the back and rump sides. The iris is blue.

In freshly hatched downy chicks, the upper bill is initially dark blue-gray. The nail is reddish brown. The lower beak is flesh-colored to light brownish. The legs, toes, and webbed feet are blackish, with the sides of the legs and toes lightened to olive gray.

Young birds are similar to females, but have a brown trunk instead of a gray one, which makes them appear much more monochrome and generally more brown in color. In addition, the light fletching on the head is missing. The initially dark yellow iris changes color to the color of the respective sex after about two months.

Possible confusion

The pochard is closely related to the North American giant pochard and the redhead, which is also native to North America, and is very similar to these two species. The head of the giant pochard looks much more wedge-shaped than that of the pochard. The main difference between these two species is the color of the beak. The bill of the giant pochard is consistently dark gray. The red headed duck lacks the dark beak base that is characteristic of the pochard.

voice

The pochard's voice is only slightly noticeable. During the courtship season, the male lets out a quiet, restrained and buzzing uiij-kijauh . It throws its head back while calling. The female, on the other hand, calls gi-gek-gek . When flying in a row , when several males are flying behind a female, one hears a barren from the duck.

A flight noise can be heard while flying.

distribution

Distribution areas of the pochard
(green = breeding areas, dark green = year-round occurrence, blue = wintering areas)

The pochard colonizes the entire European continent, southern Scandinavia and the British Isles, selectively the North African Mediterranean coast and Asia up to Lake Baikal . The main centers of the European breeding area are Belgium, the Netherlands, parts of northern and eastern France and Central and Eastern Europe. Especially in western France, Spain and Portugal as well as northern Africa, however, it is rare and usually only found as a winter guest. The northern border of the European distribution runs along the Gulf of Bothnia through the middle of Finland and Karelia . In the past few decades the species has expanded its range to the west and north. Southern Sweden was not settled until the 1920s and 1930s. The species has also been breeding sporadically in Iceland since 1954 . The colonization of parts of France has only taken place in the last few decades.

habitat

The pochard prefers large, flat, heavily overgrown inland waters as a habitat, but flat coastal zones and inland seas such as the Baltic Sea are also populated. An important feature of breeding areas is a reed belt that is not too narrow around the water or one or more islands with dense vegetation. It breeds in large bodies of water, the pochard prefers still water bays, shallow water sections and lagoons. In Hungary it also breeds on the soda lakes. In Central Asia it is a breeding bird of the brackish and salty steppe lakes.

Pochards from the northern range in particular move south in the winter months to avoid the harsh winters. They often gather in large numbers on large, ice-free lakes to hibernate there. In western and southern Europe, pochards are predominantly resident birds. They show a scattered migration, so that the winter quarters extend from western and southern Europe to North Africa. In Central Europe it winters especially in the south and southwest. It can also be observed as a wintering bird in the southwest of the Baltic Sea and on the Atlantic coast of Norway as well as in the Black Sea area and in the Middle East and South Asia. Individual and smaller troops penetrate into the south of the Sahara and overwinter, for example, in the Sahel zone from Senegal to Ethiopia and occasionally in Gambia, Uganda and Tanzania.

Pochards are often associated with tufted ducks . The two types of duck are not in competition with each other, since pochard ducks mainly feed on plant products, while tufted ducks mainly eat animal food. The pochard also only spends about 30 percent of its time and looks for its food mainly at night. The tufted duck, on the other hand, looks for food in daylight and spends considerably more time on it than the pochard.

Breeding behavior

Eggs ( Museum Wiesbaden Collection )

Pochards reach sexual maturity in their first year of life. In the majority of cases, however, they breed for the first time in their third year of life. They enter into a monogamous seasonal marriage.

Individual drakes show courtship movements even during winter. However, it is not until the end of winter that courtship begins to full and reaches its peak at the beginning of March, when the ducks have arrived in their breeding areas. The courtship of the pochard includes an extensive repertoire of courtship movements and poses, which are shown both in a social courtroom and in pairs. The pair bond only takes place in the course of spring. However, it only exists until the beginning of the breeding season. As soon as the female broods firmly, the male leaves the female.

The nesting site is chosen by the female. The nest is either built by the female directly on the water in the bank vegetation or is well hidden on islands in the breeding water. Nests are rarely made in tree hollows and further away from the shore. The six to nine eggs are usually laid in the months of May and June in the nest consisting of aquatic plants, small branches and dry grass, which is padded with down feathers. The brood is taken over by the female, but the male, which can be paired with several females, always stays nearby and sounds the alarm in case of danger. After about 25 days, the chicks, which are immediately submersible, hatch, which can fly after about 10 weeks.

The oldest ringbird was found in the UK and was 22 years and three months old.

food

The pochard looks for its food by diving or digging like swimming ducks. The diet consists of parts of reed beds and aquatic plants as well as small animals such as crustaceans , insects , but also amphibians and - far more rarely - small fish. Live mussels and annelids , tubificids and mosquito larvae play a major role at the bottom of the water . The food spectrum is very large. In principle, the animal share dominates. Depending on the seasonal and local conditions, however, the proportion of plant-based food can be very high. The number of dives with which the food is ingested varies widely. Females show a very intensive foraging for food during the 60 to 90 minute breeding break and dive between 200 and 300 times during this time.

The pochard turns out to be very adaptable in its food spectrum. In the Lusatian pond areas, for example, it prefers to eat the high-energy pellets that are actually supposed to be used to feed the carp.

Inventory and inventory development

The European population is between 210,000 and 440,000 breeding pairs, with almost 90 percent in Eastern Europe. About 41,000 to 70,000 pochards breed in Central Europe.

There was a considerable expansion of the area of ​​the pochard from the middle of the 19th century. Pochards initially settled mainly in the Baltic Sea region and Scandinavia, later they also settled in Central and Western Europe. The causes of this area expansion were the eutrophication of water bodies with a resulting increased food supply, milder winters and the creation of new bodies of water through fish ponds, reservoirs and quarry ponds. Several further area expansions in the 20th century led to an expansion in the Netherlands and Belgium. Pochards first brooded in North Rhine-Westphalia in 1933, in Switzerland in 1950 and in Austria in the early 1950s. Pochards began to settle at Lake Neusiedl from 1957. The first breeding birds were observed at Lake Constance in 1960. They first brooded on Iceland in 1964 and in Norway they have been part of the breeding bird population since 1976.

Between 1998 and 2002 there were around 200 to 300 breeding pairs in Austria. In Switzerland, however, the species is still rare, where only between two and ten pairs breed. Germany has between 4,500 and 7,500 breeding pairs. The Central European distribution focus is Poland with a breeding bird population of 20,000 to 30,000 pairs. Since the 1980s there has been a sharp decline in stocks in many countries, with the large stocks in the Czech Republic, Poland, Finland and European Russia being particularly affected. In Austria the population decreased by two thirds. The species is currently classified as endangered in Europe and worldwide. The decline has various reasons such as intensification of the management of fish ponds, overfertilization of water bodies, destruction of breeding areas, increase in predation by mink, raccoon and raccoon dog and loss of seasonal water-bearing ponds due to climate change. The preservation and management of their breeding waters is crucial for the pochard. A research team that, on behalf of the British environmental authority and the RSPB, examined the future development of the distribution of European breeding birds on the basis of climate models, however, assumes that the pochard will disappear over a wide area in Western and Central Europe by the end of the 21st century will come. According to this forecast, the area of ​​distribution will decrease significantly as a result of global warming and shift to the northeast. According to these forecasts, large parts of today's distribution area in Western, Southern and Central Europe no longer offer suitable habitats for this species.

Trivia

In the Finnish Army, the T-34 tanks of the first version with 76 mm cannon , captured by the Red Army in the Continuation War 1941–1944, were referred to as (table) duck (Finnish sotka ) because of their appearance from the front . See the picture of the swimming drake in front view above.

supporting documents

Individual evidence

  1. ↑ Viktor Wember: The names of the birds in Europe - meaning of the German and scientific names , Aula-Verlag, Wiebelsheim 2007, ISBN 978-3-89104-709-5 . P. 87
  2. ↑ a b Collin Harrison and Peter Castell: Field Guide Bird Nests, Eggs and Nestlings , HarperCollins Publisher, revised edition from 2002, ISBN 0007130392 , p. 76
  3. ↑ Hans-Heiner Bergmann; Hans-Wolfgang Helb; Sabine Baumann: The voices of the birds in Europe - 474 bird portraits with 914 calls and chants on 2,200 sonograms , Aula-Verlag, Wiesbaden 2008, ISBN 978-3-89104-710-1 , p. 63
  4. ↑ Hans-Heiner Bergmann; Hans-Wolfgang Helb: Voices of the birds of Europe - songs and calls of over 400 bird species in more than 2000 sonograms , BLV Verlagsgesellschaft, Munich a. a. 1982, ISBN 3-405-12277-5 , p. 74
  5. ↑ Rutschke, p. 251
  6. ↑ Rutschke, p. 252
  7. ↑ Bauer et al., P. 111
  8. ↑ Gooders and Boyer, p. 83
  9. ↑ Bauer et al., P. 113
  10. ↑ Bauer et al., P. 113
  11. ↑ a b Rutschke, p. 253
  12. ↑ Bauer et al., P. 111
  13. ↑ Bauer et al., P. 112
  14. ↑ Bauer et al., P. 112
  15. ^ Eva Karner-Ranner: Pochard in descent . Bird protection in Austria. 45, November 2018. 8–11.
  16. ^ Brian Huntley, Rhys E. Green, Yvonne C. Collingham, Stephen G. Willis: A Climatic Atlas of European Breeding Birds , Durham University, The RSPB and Lynx Editions, Barcelona 2007, ISBN 978-84-96553-14-9 , P. 85
  17. ↑ http://www.jaegerplatoon.net/TANKS6.htm
  18. ^ Kuusisto, Reijo: Suomalainen T-34/76 lyhytputkinen Sotka. Pienoismalli, 1994, nro 1, p. 50. Helsinki: Helsinki Media.

literature

  • 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
  • Lars Svensson , Peter J. Grant, Killian Mullarney: The New Cosmos - Bird Guide. All kinds of Europe, North Africa and the Middle East. Franckh-Kosmos Verlag, Stuttgart 1999, ISBN 3-440-07720-9 .
  • Josep del Hoyo , Andrew Elliot, Jordi Sargatal: Handbook of the birds of the world. Volume 1: Ostrich to Ducks. Lynx Edicions, Barcelona 1992, ISBN 84-87334-10-5 .
  • Erich Rutschke: The wild ducks of Europe - biology, ecology, behavior , Aula Verlag, Wiesbaden 1988, ISBN 3-89104-449-6

Web links

Commons : Pochard ( Aythya ferina )  - Album with pictures, videos and audio files
Wiktionary: Pochard  - explanations of meanings, word origins, synonyms, translations