Coot

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Coot
Coot (Fulica atra)

Coot ( Fulica atra )

Systematics
Class : Birds (aves)
Order : Crane birds (Gruiformes)
Family : Rallen (Rallidae)
Genre : Coots ( Fulica )
Type : Coot
Scientific name
Fulica atra
Linnaeus , 1758
When swimming, the coot lies relatively high in the water.

The coot ( Fulica atra ) is a medium-sized bird species of the genus of the coots ( Fulica ) from the family of the Rallen (Rallidae), which is one of the most common water birds, preferably found in nutrient-rich waters. The species is distributed over large parts of Eurasia and is also found in Australasia .

Synonyms trivial names, different spellings, feed bird

The species is sometimes also called the white-winged rail to indicate the correct taxonomic classification. The spelling with e ( Coot , Blessralle ) is also common. Other synonymous trivial names are

  • according to modern dictionaries, coot - a long time ago this term was also used for other taxa ,
  • Duck duck - historical and especially when it comes to preparation as a dish.

description

The coot is a medium-sized, rounded rail with a body length of 36 to 42 cm, which can usually be found floating on the water like a duck and is relatively high in the water. The head is relatively small, the tail short. The approximately 30 mm long, white or slightly pink-tinted bill is pointed with a curved ridge and a strong base. The eponymous blaze is a bright white horn shield above the beak, which covers the forehead and varies in size individually, according to age and between the sexes. With a length of 14 to 30 mm, it is usually slightly shorter than the beak and between 6 and 19 mm wide. If you look at the head in profile, the indentation between the upper beak and the shield forms an acute angle in contrast to other species such as the comb coot (see portrait in the picture gallery below). The feet are strong and the long toes are provided with swimming rags. The iris is colored red to dark brown-red. The sexes do not differ in plumage. Males usually have a larger forehead shield than females, but this is not a sure distinguishing feature due to the individual variation. If both are next to each other, a slight difference in size is noticeable. Females weigh around 700 g on average, males around 900 g.

Adult birds show slate-gray to blackish plumage on their backs, which shimmers from brown to olive. The throat and lower neck are darker, the head and neck are velvety black. The underside is gray to gray-brown. Very fine whitish lace hems (not visible in the field) are found on the chest and abdomen. The brown-black hand wings have whitish tips, the outermost a fine white edge. The wing plumage is predominantly blackish in color. There is an olive-brown tint on the inner arm covers, a white border on the leading edge of the wing and - a feature that is recognizable in flight - a white border on the rear edge of the arm wing. The under wing coverts are gray to light gray and show white tips in the area of ​​the hand wing. The control springs are brown-black. The legs are light ash gray, pale greenish yellow or bright yellow in color. The heel joint becomes more golden-brown with increasing age. The toes and flaps are pale olive with dirty blue-green joints. The edges of the lobes are lead-gray to blackish.

  • Head portrait

  • Toes with swimming rags

  • Leg coloring

  • Territorial dispute and wing coloring

  • with chicks

Bird in youth dress

In the youth dress , the top is brown-black. The head sides are blotchy gray-white. Sometimes a stripe above the eyes is indicated, the dark ear covers are more or less extended in the whitish cheek area. The area between the upper beak and the eye, the throat, the lower neck and the chest are dirty white. The brownish feather bases can shine through in places. The underside is dark brown-gray with barely visible whitish feather edges. The wings and control feathers are already colored like in adult birds.

This year's birds can be distinguished by the smaller horn shield until late autumn. Often they show a gray barrel with at most a hint of green, but this is not a sure sign of age.

voice

Audio sample (2.6 sec, 45 kbps, 14 kB)

Even though the vocal expressions of the coot sometimes appear very different and varied, they are often derived from the same calls, which, depending on the degree of excitement, are given softer and gentler or stronger and higher. In the latter case they often sound croaking to crane- like trumpeting or high- pitched peeping . All calls are also lined up at different intervals and speeds. The calls of females and males differ significantly. The typical coot call , a croaking but somewhat melodic crook , comes from the female. At a lower intensity, for example when luring the young birds, it can sound much softer up to a deep u- sound, but it can also become a loud "trumpet" when excited. The male's calls, on the other hand, are more voiceless and click and are aptly compared to the popping of a champagne cork. They can transform themselves into a very high and sometimes shrill pix when excited and as a warning call .

High, often two-syllable calls can be heard from migrating coots at night, especially in spring and autumn.

A rough pwieb and various squeaking sounds can be heard as begging calls from the boys , as well as a soft füid .

Distribution and subspecies

The breeding distribution of the coot extends through large parts of the Palearctic, includes the Indian subcontinent and large parts of Australasia .

In Europe, the species is absent in large parts of Fennoscandinavia , where the distribution is limited to the south. In Norway it stretches to Hedmark and Hordaland , on the Atlantic coast broken up to the Trondheimfjord , in Sweden inland about the height of Dalarna and on the coast - like Finland - to the northern edge of the Baltic Sea. In Russia, the northern border runs a little further south at about 61 ° N. In Iceland and the Azores, the species only breeds occasionally. In the north of the British Isles and in the mountains of the Mediterranean region, the distribution is only patchy. It extends south of the Mediterranean to the Maghreb and the Canary Islands .

In Asia, the northern border of the area runs in an arc that reaches its southernmost point in the Urals at 57 ° N and slowly strives through western Siberia to its northernmost point at 64 ° N at the confluence of the Aldan and the Lena . At the eastern edge of the area, the distribution probably only extends to about 54 ° N on the southern edge of the Sea of Okhotsk ; here the species breeds eastward to Sakhalin , Hokkaidō and southward to the north of Honshūs . On the continent, the distribution extends southeast to western China and Korea. While the species is absent in the inner Asian highlands and on the upper reaches of the Yellow River , it colonizes large parts of the Indian subcontinent and Sri Lanka . In a westerly direction, the area extends to the west and north of Iran and, very scattered, to the Persian Gulf , the Nile Delta and parts of Asia Minor .

Distribution of the coot:
  • Breeding areas
  • Year-round occurrence
  • Wintering areas
  • Forays (uncertain seasonality)

    • In addition to the nominate form, three other subspecies are recognized that colonize Australasia.

    hikes

    The migratory behavior of the coot varies depending on the geographical location. Some populations migrate regularly, others are stationary or line birds . The species tends to flee in winter.

    In Europe, the East-Central European, Baltic, Fennoscandian and North Russian birds mostly clear their breeding areas in winter and migrate southwest, whereby the migration routes can be of different lengths. From Denmark and East Germany, the proportion of resident birds increases to the south and west. However, some migrate south or west to winter along the coasts to France and the British Isles. Winter escapes, some of which take place over long distances, occur in all Central European birds. Most of the birds in the Mediterranean and North Africa are resident birds, but migrations can also be detected in these populations, but these are usually not directed. In Asia, most of the populations north and west of the Tibetan Plateau are migratory birds. The birds of South Asia, Southern Japan and the Australasian area are resident birds.

    The wintering areas extend from the British Isles eastwards to southern Scandinavia and southwards to North Africa and across the Mediterranean to southern Russia and the Middle East. The species occurs scattered in winter as far as the Canary Islands and Madeira , as far as the southern edge of the Sahara (for example Lake Chad or Nile Valley southwards to Khartoum ) or on the Arabian Peninsula . In Asia, the wintering areas extend over the Indian subcontinent and Sri Lanka, to the Malay Peninsula and the Philippines .

    Already in the summer large gatherings of non-breeders can be found in favorable locations, to which this year's birds and breeding birds will join later after the breeding business has been concluded. They then sometimes comprise up to several thousand copies. Presumably it is partly a collection of moulting birds. This year's birds roam around in the summer, sometimes undirected. The first real train movements start at the end of August or the beginning of September. Most of the birds migrated to their winter quarters by October. Locally, however, the train will drag on until November. The breeding areas can be re-occupied from February, but sometimes the first arrival dates are not until the end of March. The homeward movement in Central Europe continues until April. In Scandinavia and Northern Russia, the first birds sometimes don't arrive until May.

    habitat

    Chick in the water

    The coot occurs as a breeding bird in standing or slowly flowing waters, on which there are flat banks and bank vegetation suitable as a nesting site, such as a well-developed reed zone or bushes protruding into the water. Ideally, there should be flat, herbaceous areas as well as open water areas. The water must have a high or medium nutrient content. Particularly nutrient-poor waters are largely avoided - the species is therefore often lacking in mountain lakes. While brackish water lagoons are well accepted, the coot does not breed on the seashore.

    Since the size of the body of water plays a subordinate role, the coot can sometimes also be found in small forest ponds or on floodplains in swamp forests. The species is also tolerant of the environment. It also occurs partly in water bodies in closed forest areas or in cleared landscapes. A mosaic of reed beds, moist grassland, small hills or islets and bushes is preferred.

    In Central Europe, the coot breeds in eutrophic shallow water lakes, fish ponds and silting ponds, silted up bog ditches or drainage ditches, gravel pits, quarry ponds and retention basins , slow-flowing rivers and backwaters . It is also often found in residential areas, where it occurs, for example, on ponds in parks.

    nutrition

    Coot pecking

    Coots are omnivores, the composition of which varies greatly from season to region. Fresh and rotting plant parts play a significant role. They also eat waste and ducks feed, small mollusks such as zebra mussels and snails and insects and their larvae. Small fish are also eaten. During the summer, coots also eat reeds, which are high in crude protein and carbohydrates. With pure nutrition from leaves and shoots of reeds, coots need just under their body weight every day. If the density of coots is very high, the reed belt can be overused.

    Studies in Switzerland have shown that grass, green algae and aquatic plants such as milfoil , spawning herbs , waterweed and flooding water crowfoot play a role as food during the winter half-year . During the winter months, coots on the Havel in Berlin live mainly on grass, leftover bread, fallen leaves, algae and in some places mainly on mollusks. Even the smallest food particles are picked up with the head and beak on one side.

    In the plant belt of the silting zone, coots find their food by tearing off and pinching off stalks and leaves both above and just below the water surface. They look for grass and the like in fields and meadows near the shore. They also dive and dig underwater. They parasitize food particularly often in swans, but also in conspecifics and ducks. Birds that steal food from them include gudgeons, gulls, and crows.

    Reproduction

    Nest building
    Clutch
    Clutch, Coll. Wiesbaden Museum
    chick
    Fledglings

    Coots become sexually mature in the first year of life, but often do not breed for the first time until the third calendar year. The couples usually get together for a monogamous seasonal marriage. Re-mating in several subsequent years or pair cohesion in the winter half-year are not uncommon. As a rule there is one annual brood, but often two. Especially in experienced birds, three and in rare cases four have been found. If the clutch is lost, there can be up to five additional clutches.

    The pair formation usually takes place on the train, but sometimes only at the breeding site. In Central Europe, territories are sometimes defended in winter, but mostly occupied between February and early March. Nest building can begin from February. The laying time begins at the beginning of March at the earliest, is usually between the beginning / middle of April and the end of July and can extend into August. A peak can have very different characteristics locally or from year to year. In the west of the range, the breeding season is up to a month earlier, in the north and east up to a month later.

    The choice of nesting site is presumably made by the male, who often builds nesting pads in several places before deciding on one. The nesting site is usually well covered in the bank vegetation near the open water, but it is not uncommon for it to stand completely free. The nest is often located in reeds or sedge stands , but often also in willow bushes or drooping branches of other trees. The majority of the nests are in the water - most of them floating, some on a firm surface. The other nests are built on the bank or on islands on firm ground.

    The nest is an extensive structure made of plant material that is brought in from the surrounding area. Mostly it consists of stalks of reeds , bulrushes , pond sills or other bank plants, sometimes also of twigs or branches. Leaves from floating plants are less common. The nest can vary greatly in size depending on the location and be divided into a coarser substructure and a finer superstructure. The outer diameter is usually between 25 and 55 cm, the height 8–28 cm. The 16–30 cm wide and 3.5–10 cm deep hollow is lined with finer material, sometimes with grass or leaves. Sometimes one or more wide “ramps” lead to the nest. Sometimes stalks growing up next to the nest are woven into a tunnel-like hood.

    Both sexes build the nest, but often to very different dimensions. Often the male contributes a large part of the material that is used by the female. The time it takes to complete a nest varies from 1 to over 20 days. The nest is still being built during the entire breeding season. It can even happen that eggs are built in. In addition to the brood nest, the male often builds 1–2 resting nests.

    The clutch consists of 5–10 dull or slightly shiny eggs of about 53 × 36 mm in size, which are finely dotted red-brown to black on a beige to light gray background. Clutches with more than 14 eggs come from several females, smaller clutches of 3–4 eggs often occur in first broods.

    Incubation begins with the third or fourth egg and lasts between 19 and 24 days. Additional clutches are often incubated from the start. Both parents share the breeding business, with the female breeding longer and more often. In the case of the first lying, the young hatch quite synchronously within 2–5 days, in the case of subsequent lying at an interval of 1 day.

    Young coots are precocial who can swim after a short time, but usually another 2-4 days in brood brooded be fed and have some sleep for a week there. For 4–5 weeks the boys are led and fed by their parents in the family. Some of the boys stick to their father and some to their mother. These only take care of “their” part. The male builds nests to rest and sleep for the young, on which they can sometimes be huddled for longer. At eight weeks the boys are fully fledged and independent, but often stay in the area for a long time.

    Causes of mortality

    The natural causes that lead to a population decline include clutch losses due to strong water level fluctuations, high mortality rates in extremely cold winters and mass deaths due to botulism and worm infestation. Pesticide exposure and death in gill nets and muskrat traps are also major causes of death.

    Of the young birds between 75 and 87 percent die in the first year of life, of the two-year-old birds 48 to 72 percent do not experience the next year of life. The oldest ringed specimen found so far is an individual found in Denmark who lived to be 20 years and seven months old.

    Duration

    The total European population is estimated at 1.3 to 2.3 million breeding pairs. The European countries with more than 100,000 breeding pairs each include Russia, Poland, Germany, the Netherlands, Hungary, Romania and France. The coot is widespread in Central Europe. It occurs from low altitudes to altitudes of 1,400 meters. The Central European population is estimated at 410,000 to 750,000 breeding pairs.

    Basically, European coot stocks have increased over the past few decades. The species has benefited from eutrophication of water bodies, the immigration of the triangular mussel Dreissena polymorpha , a reduction in hunting pressure in Central Europe, the creation of new artificial bodies of water and an increase in winter feeding. At the same time, the species also increasingly uses water bodies in cities and was able to significantly expand the area in Northern Europe due to favorable climatic conditions. This trend is offset by a regional decrease, which is sometimes very drastic. In Baden-Württemberg the population has declined so much that the species was included in the red list. In Brandenburg there was a local decrease in breeding populations of more than fifty percent. In Hungary, the Czech Republic and, in some areas, Slovakia and Poland, there have been in some cases considerable population losses due to habitat loss since the 1970s. In Russia, in addition to the loss of habitat, intensive hunting also plays a role in the population decline.

    literature

    Web links

    Wiktionary: Coot  - Explanations of meanings, word origins, synonyms, translations
    Commons : Coot ( Fulica atra )  - Collection of images, videos and audio files

    Individual evidence

    1. ↑ Hans-Wilhelm Grömping: Blässralle . In: natur-lexikon.com . Retrieved November 13, 2019.
    2. ↑ coot, coot, the. In: Duden online . Retrieved on November 13, 2019 ("Spelling recommended by Duden: Coot").
    3. ^ Coot, Blessralle - Fulica atra LINNAEUS, 1758. In: natur-in-nrw.de. Retrieved November 13, 2019.
    4. ↑ Coot (Blessrail). In: wildtiersichtung.de. Retrieved November 13, 2019.
    5. ↑ Volume twenty - WAM – ZZ . In: Brockhaus Encyclopedia in 20 volumes . Seventeenth, completely revised edition of the Großer Brockhaus . F. A. Brockhaus, Wiesbaden 1974, ISBN 3-7653-0000-4 , entry Wasserhuhn : "→ Bleßhuhn"
    6. ^ Wasserhuhn, das. In: Duden online . Retrieved November 13, 2019.
    7. ↑ Coot / Coot. In: canoonet . Retrieved November 13, 2019.
    8. ↑ coot. In: Wissen.de -Lexikon. Retrieved November 13, 2019.
    9. ↑ coot, n . In: Jacob Grimm , Wilhelm Grimm : German Dictionary . Hirzel, Leipzig 1854–1961 ( woerterbuchnetz.de , University of Trier).
    10. ↑ Julie Sickha: Cookbook: Food like in the times of the emperor . Ed .: Hartmut Bossel . Books on Demand , Norderstedt 2016, ISBN 978-3-7412-4608-1 , pp. 414 ( limited preview in Google Book search).
    11. ↑ Eduard Teller: Guide through the three realms of nature for teachers and learners: what is worth knowing from natural history with the compilation of natural bodies and natural phenomena to form images of nature as well as a system of the natural kingdoms . tape 1 . O. Spamer, Leipzig 1875, OCLC 29789546 , p. 313 ( limited preview in Google Book search).
    12. ↑ Johannes Leunis : Nomenclator Zoologicus: An etymological explanation of the most excellent generic and species names that occur in the natural history of the animal kingdom . Hahn'sche Hofbuchhandlung, Hanover 1860, OCLC 10903371 , p. 24 ( limited preview in Google Book search).
    13. ↑ Julie Sickha: Cookbook: Food like in the times of the emperor . Ed .: Hartmut Bossel . Books on Demand , Norderstedt 2016, ISBN 978-3-7412-4608-1 , pp. 215 ( limited preview in Google Book search).
    14. ↑ Katharina Schreder: Practical cookbook with 962 cooking rules and 46 food slips . 7th, improved edition. Heinrich Kirsch, Vienna 1877, OCLC 729136318 , p. 91 ( limited preview in Google Book search): "Steamed duck"
    15. ↑ Glutz von Blotzheim, p. 519 f., See literature.
    16. ↑ a b c L. Svensson, PJ Grant, K. Mularney, D. Zetterström: The new cosmos bird guide. Franckh-Kosmos Verlags-GmbH, Stuttgart 1999, ISBN 3-440-07720-9 , p. 116 f.
    17. ↑ a b c Glutz von Blotzheim, p. 520, see literature.
    18. ↑ a b Glutz von Blotzheim, p. 524 f., See literature
    19. ^ Hans-Heiner Bergmann, Claude Chappuis, Karl-Heinz Dingler: Vogelstimmen im Flug - Bird Sounds in Flight - Voix des oiseaux en vol. AMPLE Edition Musikverlag, ISBN 978-3-938147-50-4 , p. 21.
    20. ↑ a b Glutz von Blotzheim, p. 525, see literature.
    21. ↑ a b c d Glutz von Blotzheim, p. 528 f., See literature.
    22. ^ IUCN and Internet Bird Collection, see web links.
    23. ↑ a b c Glutz von Blotzheim, p. 535, see literature.
    24. ↑ Igir Gorban, Vitas Stanevičius: Coot (Fulica atra) in Ward JM Hagemeijer, Michael J. Blair: The EBCC Atlas of European Breeding Birds - their distribution and abundance. T & AD Poyser, London 1997, ISBN 0-85661-091-7 , pp. 344 f.
    25. ↑ Martin Flade: The breeding bird communities of Central and Northern Germany: Basics for the use of ornithological data in landscape planning. IHW-Verlag, Eching 1994, ISBN 3-930167-00-X .
    26. ↑ a b c d Bauer et al., P. 411.
    27. ↑ a b c d e f g h i j Glutz v. Blotzheim, pp. 537 f., See literature.
    28. ↑ a b c Bauer et al. (2005), p. 408, see literature.
    29. ↑ C. Harrison, P. Castell, H. Hoerschelmann: Young birds, eggs and nests of the birds in Europe, North Africa and the Middle East , Aula Verlag, Wiebelsheim 2004, ISBN 3-89104-685-5 , p. 119.
    30. ↑ a b Glutz von Blotzheim, p. 559 f., See literature
    31. ↑ Bauer et al., P. 412.
    32. ↑ Bauer et al., P. 409.
    33. ↑ a b Bauer et al., P. 410.