Hen harrier

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Hen harrier
Hen harrier (Circus cyaneus), female

Hen harrier ( Circus cyaneus ), female

Systematics
Subclass : New-jawed birds (Neognathae)
Order : Birds of prey (Accipitriformes)
Family : Hawk species (Accipitridae)
Subfamily : Consecrations (Circinae)
Genre : Consecration ( circus )
Type : Hen harrier
Scientific name
Circus cyaneus
( Linnaeus , 1766)
Hen harrier in youth dress

The hen harrier ( Circus cyaneus ) is a bird of prey from the hawk family (Accipitridae). The distribution area extends over large parts of the northern Palearctic . The species inhabits large areas of open, moderately moist to dry habitats such as the open taiga , moors, heaths, silting areas and steppes , regionally also young coniferous wood afforestations and areas used for agriculture.

Hen harriers, depending on their geographical distribution, range from resident birds to long-distance migrants ; they overwinter in Central and Southern Europe, the Near and Middle East and southern East Asia. In inland Central Europe, the species has largely become extinct due to habitat destruction; the 2015 Red List of Germany's breeding birds classifies it in Category 1 as critically endangered. However, the species is not endangered worldwide.

description

Male hen harrier
Male hen harrier

Hen harriers are medium-sized, but relatively slender and light birds of prey. In flight, the wings are quite wide at the base, the wing tip is formed by four wingtips and is therefore quite round. The body length is 42–55 cm, the wingspan 97–118 cm. Like many species of the genus Circus , the hen harrier also shows a strong sexual dimorphism in terms of size and color. Adult males from Europe weigh 300–400 g, which is less than a wood pigeon . They have a wing length of 330–362 mm, on average 340.5 mm. The significantly larger and heavier females reach a weight of 370–708 g and a wing length of 338–402 mm, on average 373 mm.

In adult males, the head and neck, the upper side of the trunk, the upper wing-coverts, the upper side of the arm-wings and the inner hand- wings as well as the upper side of the tail are monochrome blue-gray, the rump is white. The middle and outer wings of the hand are sharply defined above and below, monochrome black. The entire remaining underside is monochrome white except for the dark gray end band of the arm and inner hand wings. The blue-gray neck is sharply set off from the white underside.

Adult females are monochrome medium brown on the top of the head, back neck, back and upper wing coverts, the small arm coverts are somewhat lightened in the middle of the wing. The wings are banded blackish on top on a gray-brownish background and also show a blackish tip. The rump is clearly contrasting white. The control feathers are banded in black on a light brown background and show a wide black end band. The bottom is lighter overall. The neck, trunk and under wing-coverts are dotted with strong brown dots on a yellowish white background, the dotted lines become weaker towards the lower abdomen. The undersides of the wings and control feathers are broadly banded from dark brown to black on a light gray background and show a wide, dark end band. The head shows a narrow, dark stripe of eyes, which is rather indistinctly and narrowly framed in white above and below the eye. A facial veil is pronounced and clearly narrowly whitishly limited towards the neck. Like the rest of the top, the wide cheek band is medium brown and hardly contrasts in color.

Birds in juvenile plumage are colored similar to adult females on the upper side, but more dark brown. With them, the arm wings are almost monochrome, dark gray-brown. In addition, the large upper wing ceilings are lightly edged. The throat, the entire underside of the trunk including the leg fletching and the under tail-coverts as well as the under wing coverts are more beige-brown, the dotted lines of the trunk are largely limited to the chest and upper abdomen. The darker arm wings form a clear contrast to the lighter hand wings below.

The first downy dress is white, the second is light reddish red or pale beige on top, lighter on the flanks and white on the underside. The edge of the beak, legs, wax skin and claws are pink when hatched. The beak is black. In growing downy chicks, the wax skin and legs gradually turn yellow, the claws black.

The iris is yellow in adult birds of both sexes. Older nestlings have a dark iris that turns gray in males before they fly out and turns yellow by autumn. Females have a dark brown iris when they fly out; this color is retained until the 2nd or 3rd calendar year. The iris turns amber up to around the 4th or 5th calendar year and is only bright yellow from around the 7th calendar year. Wax skin and legs are yellow in all clothing, the beak and claws black.

Vocalizations

The male's courtship calls consist of quickly lined up, chopped-off calls that can be reproduced with "chuk-uk-uk-uk-uk" or "chukukerr-kerruk-chuckerukeruk". When threatened at the nest, females utter quick, chirping calls, like "chit-it-it-it-et-it-et-it-et ...", the alarm calls of the males are somewhat deeper like "chek-ek- ek-ek "or" kekekeke ... ". The call that young birds constantly use when begging is a thin "psieh-psieh ..."; Similar to "psiih-e" or "bijuh" sounds like the begging call of the females.

distribution and habitat

Distribution of the hen harrier (green = breeding area, blue = occurrence only in winter)

The distribution area of ​​the hen harrier covers large parts of the northern Palearctic . It stretches in west-east direction from Ireland and north-west Spain to Kamchatka , in north-south direction in western Europe roughly from the Arctic Circle to north-west Spain, further east to south to southern Poland, southern Ukraine , and north Kazakhstan and Mongolia and Northeast China. In Central Europe, the distribution has always been largely limited to the Central European lowlands between Belgium and Poland. Occurrences south of the low mountain range were and are only sporadic in Germany and in Austria exceptionally in mouse-rich years; in Switzerland the hen harrier is absent as a breeding bird.

The species inhabits large areas of open, moist to dry habitats such as the open taiga, moors, heaths, siltation zones and steppes, regionally also young coniferous forest afforestations and especially in south-western Europe also grain fields. The breeding habitats can also vary greatly from region to region. For example, in a Dutch moorland, 23 of 38 breeding sites were located in about half of the already forested silting areas, a further 11 in small clearings in the already closed wet or wet forest and only 4 in more open habitats characterized by reeds, blue pipegrass and rubus bushes . In the interior of Lower Saxony 27 hatcheries were 1976-1985 known of these were 6 in fens , swamps or wet grassland, 17 in high or transition bogs, one in a Calluna - Heath and 3 in winter cereals. On the islands off the North Sea coast of Lower Saxony and Schleswig-Holstein, hen harriers breed today predominantly in wet dune valleys with isolated reed beds , creeping willows and uneven growth of birch trees .

Systematics

No subspecies are recognized for the Palearctic. The only consecrations in North America were previously regarded as a subspecies of the hen harrier, but are now separated as a separate species Circus hudsonicus ( Hudson consecration ). According to molecular genetic studies, the corn and Hudson harrier are clearly different species.

The specific epithet " cyaneus " comes from ancient Greek and means steel blue. It refers to the color of the male.

Hunting style and diet

Like other harriers , hen harriers hunt over open terrain mainly in a low, swaying, rocking search flight with their wings held up slightly. The prey is caught on the ground from a short distance and caught. The species also hunts less often from the hide and especially when hunting birds with direct approaches. The diet consists almost exclusively of mammals up to the size of young hares and rabbits and birds up to the size of a Ptarmigan . Other small vertebrates such as lizards , snakes or fish, like insects, have only rarely been detected as prey in Europe. The main food in summer and winter quarters is mostly voles and, especially when these are rare, small songbirds .

Reproduction and Age

The species usually breeds individually, but with high density and good food availability, loose colonies form. It has also been observed several times that individual pairs establish themselves in the vicinity of group-wise breeding Montagu's harriers. Hen harriers usually lead a monogamous seasonal marriage. Primarily older and experienced males are, however, often bi- or polygyn , mated with two or more females , especially with higher settlement densities. A maximum of seven females were detected in one male.

The courtship consists primarily of spectacular display flights by the male, rarely by both partners. The male shows waves flying at high altitudes, loops , dives with twisting twists and turns; it calls often. These mating flights are usually accompanied by the female at a lower altitude or pursued while sitting. The courtship also includes mock attacks by the male on the female, which the female throws on her back to defend against, as well as sliding and circling together. Often the male has prey with him during these courtship flights, which it then passes on to the female, which is then followed by mating.

Like most consecrations, the species is ground breeder. The nest is usually directly on the ground on dry to swampy ground in dense vegetation. What is striking about this species is the often pronounced retention of a certain breeding site.

Gelege, Museum Wiesbaden collection

The nest is often only 5 cm high on dry ground, but up to 30 cm high on wet ground. It is made of twigs on the outside and finer plant material such as dry grass, reeds, heather or thin twigs on the inside. The outer diameter is usually 40–45 cm, up to a maximum of 65 cm. The start of laying varies depending on the geographical distribution, but is fairly uniform in Europe at the earliest in mid-April, on average mostly in early May to early June, at the latest from late June to early July. The clutch consists of 2–7, mostly 4–6 eggs. The eggs are mostly pure white, only occasionally spotted reddish brown. Eggs from Germany measured an average of 45.3 × 35.5 mm, from the Orkney Islands an average of 46.3 × 34.6 mm. The incubation period is 29–30 days, the nestling period 31–42 days.

The eggs are incubated and the nestlings are fed and guarded until about 3 weeks after they hatch almost exclusively by the female, who is supplied with food by the male during this time. Then the female begins to hunt again. At 20 days, the nestlings can eat undivided prey independently, but are still occasionally fed by the female at the age of 28 days. After the fledgling, the young birds are provided with food by their parents for two to three weeks. Hen harriers defend clutches and young birds with great vehemence, and the females in particular often attack people close to the nest and hit bleeding wounds with their claws.

The maximum age proven by ringing is 16 years and 5 months, a number of other birds lived to be 12 to 14 years old.

hikes

Hen harriers, depending on their geographical distribution, range from resident birds to long-distance migrants; they overwinter in Central and Southern Europe, in North Africa, in the Near and Middle East and in southern East Asia. Withdrawal from the breeding areas takes place in August; in Central Europe, emigration usually reaches its peak in October and expires in November. In Central Europe, winter escapes can still occur in January and February. The migration starts here at the end of February and ends in April or beginning of May, the breeding grounds in Central and Western Europe are occupied from the end of March.

Existence and endangerment

The world population was estimated at around 70,000 breeding pairs in 2001, the population of the western Palearctic around the year 2000 at around 45,900 pairs. The majority of them live in Russia with 20,000–40,000 couples alone. Other large populations in Europe are France with 9700, Finland with 1500–3500 and Spain with 800–860 pairs. The world population is considered safe according to the IUCN .

In Europe, from around the end of the 19th century, as a result of the extensive destruction of the original habitats through drainage and intensive agricultural use of the lowlands, moors and heaths and the general intensification of use of the open landscape, there was a drastic collapse of the population. While the populations in western and south-western Europe stabilized, especially after 1990, and also increased significantly in Great Britain, France and Spain, the hen harrier is largely extinct in the Central European interior today. In the Netherlands and Germany, small populations were able to establish themselves on the North Sea islands from the middle of the 20th century and only hold them there; in Poland there are still small populations in the river plains.

Stock development in the Netherlands

In the Netherlands, the inland breeding habitats were increasingly destroyed from around 1940, but at the same time the North Sea islands were colonized from 1940. Between 1960 and 1990, dikes caused short-term population increases in the polder area , but after 1990 over 90% of the annual population was breeding on the Dutch North Sea islands. The reasons for the successful settlement of the islands are unclear. The population increased there particularly in the 1960s and 1970s, but fell from the mid-1990s to 95–100 pairs in 1998 and 1999. The reproduction and survival rate of birds in the first year of life decreased significantly in the 1990s; today the population is therefore no longer considered to be able to survive without immigration from outside.

Inventory development in Germany

In Lower Saxony the hen harrier was a widespread, if not a frequent breeding bird around 1900. By the early 1980s, the known inland breeding grounds were largely destroyed by industrial peat extraction, drainage and afforestation. In the years 1981–1985 only a few pairs brooded in the interior, in 1995 there was only one breeding site there. The Frisian islands off the coast of Lower Saxony were settled from 1952. In Lower Saxony, this settlement is primarily attributed to land reclamation measures, which enabled vole and rabbit populations to establish themselves on the islands all year round. In the years 1981–1985 around 10–20 pairs bred on the islands in 2004, 45–50 pairs.

In Schleswig-Holstein the hen harrier was an irregular and isolated breeding bird with a maximum of 5 pairs until the end of the 1980s, especially in the east of the state. From 1989 the species was able to establish itself as a regular breeding bird and the population increased very slowly. In 1999 there were 6 breeding pairs, 4 of which were breeding on Sylt and 2 in the Speichererkoog Dithmarschen on the west coast of the country.

In parts of Brandenburg the species was even more common than the Marsh Harrier around 1900 . In 1969 and 1970 a remainder of 45–50 pairs was determined, which almost exclusively brooded in the silting areas of larger lakes. Due to the almost complete destruction of the fens in the vicinity of the breeding habitats after 1965, the hen harrier died out; the last brood was recorded in 1993.

In the years 2011–2016, 8 to 9 breeding pairs were recorded throughout Germany. The population has decreased significantly over the past 36 years. In the Red List of Germany, the Harrier is therefore threatened with extinction (category 1) classified.

Inventory development in Poland

In the Polish lowlands, as in Brandenburg in the 19th century, the species was even more common than the Marsh Harrier. From the middle of the 19th century, the population decreased drastically here as well. In 2003 there were still small remnants in the lowlands of the Oder and Warta in the west and on the Biebrza in the east of the country. In 2003, the total population in Poland was estimated at around 30-40 pairs in the event of great uncertainty.

supporting documents

Individual evidence

  1. ↑ Christoph Grüneberg, Hans-Günther Bauer, Heiko Haupt, Ommo Hüppop, Torsten Ryslavy, Peter Südbeck: Red List of Germany's Breeding Birds , 5 version . In: German Council for Bird Protection (Hrsg.): Reports on bird protection . tape 52 , November 30, 2015.
  2. ^ Lars Svensson, Peter J. Grant, Killian Mullarney, Dan Zetterström: Der neue Kosmos Vogelführer . Kosmos, Stuttgart 1999, ISBN 3-440-07720-9 , p. 86.
  3. ↑ UN Glutz v. Blotzheim, KM Bauer, E. Bezzel: Handbook of the birds of Central Europe. 2nd Edition. Volume 4, Aula-Verlag, Wiesbaden 1989, ISBN 3-89104-460-7 , pp. 346-347.
  4. ↑ UN Glutz v. Blotzheim, KM Bauer, E. Bezzel: Handbook of the birds of Central Europe. 2nd Edition. Volume 4, Aula-Verlag, Wiesbaden 1989, ISBN 3-89104-460-7 , p. 350.
  5. ↑ L. Svensson, PJ Grant, K. Mullarney, D. Zetterström: The new cosmos bird guide . Kosmos, Stuttgart 1999, ISBN 3-440-07720-9 , p. 86.
  6. ↑ UN Glutz v. Blotzheim, KM Bauer, E. Bezzel: Handbook of the birds of Central Europe. 2nd Edition. Volume 4, Aula-Verlag, Wiesbaden 1989, ISBN 3-89104-460-7 , pp. 351-355.
  7. ↑ L. Sachslehner, F. Gubi, H. Lauermann: A successful brood of the Hen Harrier (Circus cyaneus) in the Horner Basin (Lower Austria) in 2005. In: Egretta. 48, 2005, pp. 88-95.
  8. ^ RG Bijlsma: Ecological Atlas van de Nederlandse Roofvogels. Schuyt & Co, Haarlem 1993, ISBN 90-6097-348-8 , p. 104.
  9. ↑ H. Heckenroth, J.-U. Heins: Hen harrier. In: H. Zang, H. Heckenroth, F. Knolle: The birds of Lower Saxony - birds of prey. (= Nature conservation and landscape management in Lower Saxony. Special series B, booklet 2.3). 1989, ISBN 3-922321-47-X , pp. 102-103.
  10. ↑ including RE Simmons: Harriers of the world: their behavior and ecology. Oxford University Press, 2000, ISBN 0-19-854964-4 .
  11. ^ Graham J. Etherington, Jason A. Mobley: Molecular phylogeny, morphology and life-history comparisons within 'Circus cyaneus' reveal the presence of two distinct evolutionary lineages. In: Avian Research. 7 (17), 2016, doi: 10.1186 / s40657-016-0052-3 .
  12. ↑ 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. 98.
  13. ↑ UN Glutz v. Blotzheim, KM Bauer, E. Bezzel: Handbook of the birds of Central Europe. 2nd Edition. Volume 4, Aula-Verlag, Wiesbaden 1989, ISBN 3-89104-460-7 , pp. 363-364 and 367-369.
  14. ^ RG Bijlsma: Ecological Atlas van de Nederlandse Roofvogels. Schuyt & Co, Haarlem 1993, ISBN 90-6097-348-8 , p. 105.
  15. ↑ UN Glutz v. Blotzheim, KM Bauer, E. Bezzel: Handbook of the birds of Central Europe. 2nd Edition. Volume 4, Aula-Verlag, Wiesbaden 1989, ISBN 3-89104-460-7 , pp. 364-3365.
  16. ↑ UN Glutz v. Blotzheim, KM Bauer, E. Bezzel: Handbook of the birds of Central Europe. 2nd Edition. Volume 4, Aula-Verlag, Wiesbaden 1989, ISBN 3-89104-460-7 , p. 360.
  17. ↑ E. Bezzel: Compendium of the birds of Central Europe. Nonpasseriformes - non-singing birds . Aula, Wiesbaden 1985, ISBN 3-89104-424-0 , p. 246.
  18. ^ J. Ferguson-Lees, DA Christie: Raptors of the World. Christopher Helm, London 2001, ISBN 0-7136-8026-1 , p. 483.
  19. ↑ T. Mebs, D. Schmidt: The birds of prey in Europe, North Africa and the Middle East. Franckh-Kosmos, Stuttgart 2006, ISBN 3-440-09585-1 , p. 263.
  20. ↑ T. Mebs, D. Schmidt: The birds of prey in Europe, North Africa and the Middle East. Franckh-Kosmos, Stuttgart 2006, ISBN 3-440-09585-1 , pp. 263-264.
  21. ↑ RG Bilsma, F. Hustings, K. Camphuysen: Algemene en schaarse bird van Nederland . GMB Uitgeverij / KNNV Uitgeverij, Haarlem / Utrecht 2001, ISBN 90-74345-21-2 , p. 147.
  22. ↑ H. Heckenroth, J.-U. Heins: Hen harrier. In: H. Zang, H. Heckenroth, F. Knolle: The birds of Lower Saxony - birds of prey. (= Nature conservation and landscape management in Lower Saxony. Special series B, booklet 2.3). 1989, ISBN 3-922321-47-X , p. 96.
  23. ↑ T. Mebs, D. Schmidt: The birds of prey in Europe, North Africa and the Middle East. Franckh-Kosmos, Stuttgart 2006, ISBN 3-440-09585-1 , p. 263.
  24. ↑ H. Heckenroth, J.-U. Heins: Hen harrier. In: H. Zang, H. Heckenroth, F. Knolle: The birds of Lower Saxony - birds of prey. (= Nature conservation and landscape management in Lower Saxony. Special series B, booklet 2.3). 1989, ISBN 3-922321-47-X , pp. 96-107.
  25. ↑ T. Mebs, D. Schmidt: The birds of prey in Europe, North Africa and the Middle East. Franckh-Kosmos, Stuttgart 2006, ISBN 3-440-09585-1 , p. 263.
  26. ^ RK Berndt, B. Koop, B. Struwe-Juhl: Vogelwelt Schleswig-Holstein. Volume 5: Breeding Birds Atlas. 2nd Edition. Karl Wachholtz, Neumünster 2003, ISBN 3-529-07305-9 , pp. 126-127.
  27. ↑ M. Feiler, M. Kolbe: Hen harrier - Circus cyaneus. In: E. Rutschke (Ed.): The bird world of Brandenburg. Aula-Verlag, Wiesbaden 1987, ISBN 3-89104-426-7 , p. 164.
  28. ^ M. Kolbe, B. Ludwig: Hen harrier - Circus cyaneus. In: Association of Berlin-Brandenburg Ornithologists (ABBO): The bird world of Brandenburg and Berlin . Natur & Text, Rangsdorf 2001, ISBN 3-9807627-5-0 , pp. 170–171.
  29. ↑ Federal Ministry for the Environment, Nature Conservation and Nuclear Safety (ed.): The situation of nature in Germany. Results of the EU bird protection and FFH report. Berlin, Bonn 2020.
  30. ↑ Z. Głowaciński (ed.): Polish Red Data Book of Animals - Vertebrates. Warszawa 2001, ISBN 83-09-01735-9 , pp. 143-145.
  31. ↑ L. Tomiałojć, T. Stawarczyk: Awifauna Polski. Volume 1, Wrocław 2003, ISBN 83-919626-1-X , pp. 218-221.

literature

  • E. Bezzel: Compendium of the birds of Central Europe. Nonpasseriformes - non-singing birds . Aula, Wiesbaden 1985, ISBN 3-89104-424-0 , pp. 243-246.
  • Urs N. Glutz von Blotzheim , Kurt M. Bauer , E. Bezzel: Handbook of the birds of Central Europe. 2nd Edition. Volume 4, Aula-Verlag, Wiesbaden 1989, ISBN 3-89104-460-7 , pp. 337-369.
  • D. Forsman: The Raptors of Europe and the Middle East - A Handbook of Field Identification . T & AD Poyser, London 1999, ISBN 0-85661-098-4 , pp. 183-195.
  • Lars Svensson , Peter J. Grant, Killian Mullarney, Dan Zetterström: The new cosmos bird guide. Kosmos, Stuttgart 1999, ISBN 3-440-07720-9 , pp. 86-87.

Web links

Other websites

Commons : Hen Harrier  - Collection of images, videos and audio files
Wiktionary: Hen harrier  - explanations of meanings, word origins, synonyms, translations
This version was added to the list of articles worth reading on July 18, 2010 .