Peregrine falcon

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Peregrine falcon
Peregrine falcon (Falco peregrinus), female with nestling

Peregrine falcon ( Falco peregrinus ), female with nestling

Systematics
Class : Birds (aves)
Order : Falk-like (falconiformes)
Family : Falconies (Falconidae)
Subfamily : True falcon (Falconinae)
Genre : Falcon ( falco )
Type : Peregrine falcon
Scientific name
Falco peregrinus
Tunstall , 1771
Portrait of a peregrine falcon

The peregrine falcon ( Falco peregrinus ) belongs to the falcon family ( Falconidae ). It is one of the largest members of the family and, with a top speed of 320 km / h, is the fastest animal on the planet. The peregrine falcon is a cosmopolitan and the most widespread bird species in the world; it colonizes all continents except for Antarctica . Peregrine falcons are primarily rock breeders and primarily inhabit mountainous landscapes of all kinds and cliffs. In the last few decades the species has colonized cities and industrial plants with their numerous "artificial rocks" in many parts of the distribution area.

Peregrine falcons are highly specialized bird hunters; the diet consists almost exclusively of small to medium-sized birds that are hunted in the open air. The dives from great heights while hunting and the high speeds achieved are spectacular. The collapse in populations caused by the insecticide DDT and the subsequent population recovery with the settlement in many cities have made the peregrine falcon one of the world's best-known species of birds of prey .

description

Colored ( adult ) peregrine falcons are dark blue- gray on the entire upper side. The underside is mostly dark, cross-banded on a white to cream-colored background, only the front neck and the upper chest are very variable, light to strong, dark spots or dashed lines. The very strong, black stripe of beard, which is sharply set off from the light throat, is characteristic of the species. The iris of the eyes is dark brown, wax skin, eye ring and legs are yellow, the claws are black.

While the colouration of the sexes is very similar, peregrine falcons show a strong reverse sex dimorphism in terms of body size. Small males have a body length of 35 cm and a wingspan of 79 cm, large females have a body length of 51 cm and a wingspan of 114 cm. Central European males have a wing length of 289–334 mm and weigh 550–750 g, the wing length of females from this area is 339–375 mm and the weight 740–1300 g. Peregrine falcons are among the largest species of the genus Falco , only saker falcon and gyrfalcon are even larger.

The flight pattern of the peregrine falcon is typically falcon-like with a strong trunk, a large head, relatively long, somewhat triangular, pointed wings and a medium-long, slightly rounded tail. The best distinguishing features are the very dark top, the light, cross-banded underside and the streak of beard that can be seen from a distance. Often the species can also be recognized based on its behavior (see below).

Young birds that have just flown out differ considerably from the adult (colored) birds. Young peregrine falcons are black-brown on the upper side, all cover feathers have a light brownish border. The underside has dark brown longitudinal stripes on a reddish brown background. The cheek stripe is less strong than in the adult falcon and stands out much less against the red-brown sides of the head. The wax skin and the eye ring are blue-gray; the legs of the chick too. Peregrine falcons molt into the adult dress from the spring of the second calendar year, i.e. at the age of approx. 12 months, and are no longer distinguishable from the adults in the autumn of the second calendar year.

The size and coloration of subspecies in other parts of the world differs considerably from that of the peregrine falcon in Central Europe.

Vocalizations

Both sexes call frequently near the breeding site. The courtship call uttered when handing over prey or when “showing the nest” is a clearly audible, clearly two-syllable, stringed “akzick-akzick” that is repeated faster and faster with increasing excitement. The alarm call is a penetrating, sharp "eeek-eeeek-eeeeek", which is drawn out in the case of minor disturbances. In the event of massive disruptions (e.g. nest controls), this call is uttered by the falcons circling over the breeding site, which then usually sounds like "eek-eek-eek-eek". This reputation is also known as Lahnen. Far less noticeable, for example, is the warning call with which the partner is made aware of a disorder; it sounds like "kjuck" and can only be heard from a short distance.

distribution and habitat

Peregrine falcon habitats according to the Handbook of the Birds of the World
  • Breeding areas in summer
  • Annual breeding areas
  • Wintering areas
  • Intermediate stops while hiking
  • Distribution map of the subspecies
    The Saxon Switzerland is one of the best habitats felsbrütender peregrine in Central Europe

    Peregrine falcons are found on all continents except Antarctica . They have also populated most of the larger islands and archipelagos, they are only missing on the islands of the Caribbean , New Zealand and Iceland . The peregrine falcon is the most widespread bird in the world. The worldwide distribution of the species is essentially due to its very unspecific habitat requirements; these are ultimately limited to a secure breeding opportunity and free air space with a sufficient supply of birds.

    Peregrine falcons are rock breeders in the greater part of the range. They can therefore be found worldwide mainly in regions with rocks. Closed forested and / or extensive rock-free areas are only populated regionally in Central and Eastern Europe, in the northwest of North America and in parts of Australia; Here, peregrine falcons breed in raptor nests or in large tree hollows, although tree hollows are only used in North America and Australia. The species also only breeds regionally as a ground breeder in large moors , especially in the Baltic States and in northern Scandinavia , Finland and Russia. Peregrine falcons are absent in the tropical forests of the lowlands of South America and Africa and in the steppe regions of Asia. They also avoid the arid zones of America , Africa, and interior Australia .

    In many parts of the world, especially in Europe and North America, peregrine falcons have also colonized tall structures as "artificial rocks" in the last few decades. This is partly aided by the fact that there is often a preferred prey for peregrine falcons - the domestic pigeon - in large numbers.

    Outside the breeding season and in winter quarters, peregrine falcons can also be found in bird-rich habitats of all kinds, e.g. B. also on coasts and in large wetlands.

    Systematics

    External system

    The species status of the peregrine falcon is undisputed, but the systematic position within the genus Falco has not yet been conclusively clarified. In a systematic investigation, using the mitochondrial cytochrome -b gene has been a for the type sister group ratio to the bulk of the falcon Hierofalco group ( Lannerfalke , gyr , Sakerfalke and Laggar Falcon ) and Prairie Hawk detected. In a further investigation on the basis of the CR region of the mitochondrial DNA , however, a sister group relationship to the prairie falcon was found, both species here formed a sister taxon to the Hierofalco group.

    Internal system

    Peregrine falcons show a significant increase in size to the north. In addition, the peregrine falcons are generally relatively dark in humid climates, and become lighter in drier climates. The delimitation of the subspecies is complex and is discussed intensively in science. The transitions between the subspecies are mostly fluid; depending on the author, the number and geographical delimitation of the subspecies often differ considerably.

    Subspecies babylonicus , drawing by John Gould 19th century

    The following presentation is essentially based on Ratcliffe (1993). A total of 19 subspecies are distinguished:

    • F. p. peregrinus : Temperate and boreal zone of Eurasia from Ireland to Eastern Siberia.
    • F. p. calidus : (Synonym: F. p. leucogenys ) North adjoining nominate form ; Eurasian tundra from the Kola Peninsula to the east to the Lena .
    • F. p. japonensis : to the east adjoining nominate form; Eastern Siberia , Kamchatka , Japan .
    • F. p. brookei : adjoining nominate form to the south; from the Iberian Peninsula to the east via Italy , the Balkans and Turkey to Iraq and Iran .
    • F. p. babylonicus : Mountains and high mountains in central Iran, Afghanistan , southern Himalayas to western Mongolia. Previously classified as a subspecies of the desert hawk.
    • F. p. peregrinator : Indian subcontinent, Indochina south to and including Malaysia . Species status is discussed.
    • F. p. ernesti : Oceania ; Indonesia , Philippines , New Guinea .
    • F. p. furuitii : Ogasawara Islands (about 1000 km southeast of Honshū ).
    • F. p. macropus : north and east of Australia .
    • F. p. submelanogenys : Southwest Australia.
    • F. p. nesiotes : Pacific islands east of Australia; Vanuatu , Fiji .
    • F. p. pelegrinoides : north-west (from Mauritania and Canary Islands to the east to Tunisia ) and north-east Africa ( Egypt , Sudan ) and north-west of the Arabian Peninsula ( Israel , Syria ). Was previously classified as the nominate form of the desert hawk . Another name was also a Berber falcon.
    • F. p. madens : Cape Verde .
    • F. p. minor : Africa south of the Sahara .
    • F. p. radama : Madagascar .
    • F. p. tundrius : Arctic North America .
    • F. p. anatum : south on F. p. tundrius subsequently; North America; to the south about northern Mexico , further east to Mississippi. Species status of falcons on the east coast (formerly anatum) is unclear as peregrine falcons of various subspecies have been released into the wild.
    • F. p. pealei : West coasts of Canada and Alaska, also on the Aleutians and on the commanders' islands.
    • F. p. cassini : Andes from Colombia to the southern tip of South America . F. kreyenborgi has emerged as a light morph from F. p. cassini exposed.

    Hunting way

    Peregrine falcon in flight

    Peregrine falcons almost exclusively hunt birds in the open air. Since a covered approach to the prey is not possible here, the element of surprise is reached by approaching it with the greatest possible speed. The prey then only has a very short time window to react. The two essential hunting techniques are of ball impact from a great height, and the flat impact from a waiting .

    On the steep thrust, the falcon circles at a greater height and waits for birds to fly under it. The falcon then falls into the dive and puts on the wings, the control is done with the thumb wings . Most likely, the hawks use their unopened feet for the actual strike. After the blow, the falcon flies past the prey due to its high speed and then returns to it in a curve. The prey is often killed by the impact alone, if it is only injured the hawk will kill it with a bite on the neck. Birds that notice the approaching falcon in time immediately begin to circle very closely. The approaching falcon cannot take part in this maneuver due to its high speed and is then usually unsuccessful. Peregrine falcons reach very high speeds when they dive. Reports announced top speeds of over 300 km / h and even up to 400 km / h in the rare vertical dive.

    In the case of a flat strike from a control room, the prey is approached from behind and slightly offset below the prey. Peregrine falcons can quickly catch up with any other bird in straight flight, so here the falcon creates the element of surprise by quickly approaching the prey in the “blind spot”. The prey bird is then grabbed from behind and below. If birds notice the hawk's approach in time, they have a relatively good chance of escaping. Smaller birds (e.g. starlings ) drop immediately, larger ones such as pigeons try to escape by flying very tight curves, similar to steep bumps, and in these cases too the falcon is usually unsuccessful due to its inadequate maneuverability.

    These two basic patterns of hunting are varied or combined in many ways. Especially outside the breeding season, the pairs often hunt together, the approach to a prey bird then takes place at a certain distance from each other, so that the second falcon can follow up on the evasive bird if the first one fails. If the bird moves upwards, one of the hawks follows the bird upwards, while the other (usually the female) circles under the prey bird, thus cutting off the way down.

    nutrition

    Peregrine falcon with prey in its catch
    Peregrine falcon female breeding in nest basket in a tree
    Peregrine falcon clutch of four in a nesting box of the working group Peregrine Falcon Protection NRW
    Flying Peregrine Falcon on the California coast

    Peregrine falcons eat almost exclusively small and medium-sized birds. The maximum weight of the prey is around 500 g, which corresponds roughly to the weight of a wood pigeon or a carrion crow . Most prey birds, however, are significantly lighter.

    Which species dominate the prey spectrum depends on the local supply. Peregrine falcon hunting methods are most successful with birds that fly straight for long distances. In large parts of Western and Central Europe, domestic pigeons therefore dominate the prey. In the summer half of the year, these are mainly the carrier pigeons released in large numbers for races over great distances , in cities and on rocky coasts additionally wild street pigeons or the rock pigeon . Migratory birds, especially thrushes and starlings, play an important role in nutrition, especially in autumn and spring . On the coast, peregrine falcons live mainly on sea birds such as gulls , guillemots and alks .

    Peregrine falcons hunt well into twilight; Bats , especially early flying species such as noctule bat , are therefore the only regularly preyed mammals. In large cities Peregrine use the great artificial light supply and hunt at night migrating birds such as Coot and waders , in Berlin for. B. often water rails , corncocks and woodcock .

    Reproduction and Age

    Egg,
    Museum Wiesbaden collection

    Peregrine falcons are sexually mature in the second calendar year, i.e. around 9 months of age. However, individuals born in the previous year are very rare as breeding birds in intact populations due to the great intra-species competition.

    Peregrine falcons can be found in their territories all year round in Central Europe. From around January the usually not very conspicuous courtship begins with the district partners sitting close to each other waiting and circling together over the district when the weather is good. About 6 weeks before the egg is laid, the male begins to feed the female with prey, and the female is then hardly active. The high point of courtship is reached a few weeks before the eggs are laid. In addition to the handing over of prey, it now consists primarily of the male's “nesting”. This scratches a hollow at the potential breeding grounds and tries to lure the female there by loudly "zipping".

    Peregrine falcons, like all falcons, do not build nests. Rock breeders use existing small caves or ledges as well as abandoned nests of other larger birds breeding in rock walls, e.g. B. Common ravens . Tree-nesters use abandoned nests of birds of prey, herons or common ravens. In Central Europe, eggs are usually laid in mid-March to mid-April, exceptionally as early as the end of February or, especially if they lie behind, until mid-May. The clutch size is usually 3–4 (1–5) eggs. The eggs are quite round, measure an average of 51 × 41 mm and weigh 39–48 g. They are very densely spotted red or yellow-brown on a yellowish background and therefore often appear monochrome brown from a greater distance. The incubation period is 34–38 days. The young birds fly out at around 42 days (males) or 46 days (females). The young birds usually stay in their parents' territory for about 4 to 6 weeks and then migrate. Peregrine falcons reach a maximum age of over 15 years, the proven maximum age is almost 18 years.

    Peregrine Falcon in youthful dress at Morro Rock, California

    hikes

    Peregrine falcons, depending on their occurrence, range from resident birds to long-distance migrants ; the tendency to move increases to the north. The populations of the tropical and Mediterranean zones are resident or at best line birds . In central, northern and eastern Europe, many peregrine falcons migrate to western and southwestern Europe, especially in the first year of life, and overwinter there, but the adult peregrine falcons are predominantly resident birds here. The arctic peregrine falcons are long-distance migrants. The birds of the Arctic of Canada and Alaska migrate to Central and South America, the peregrine falcons of the Russian Arctic winter in Africa and southern Asia.

    Population development and endangerment

    Peregrine falcons have been pursued intensively by pigeon breeders since at least the end of the 19th century, and egg collectors also hunted down peregrine falcons at least regionally. Due to the inaccessibility of many breeding sites, however, this persecution only led to greater population declines in regions.

    A large-scale, catastrophic decline in the peregrine falcon population was discovered in the UK in 1961 . A census in 1962 found a population decline of 44% for the entire country compared to the mean population for the years 1930–1939. In the south of England the species had completely disappeared, in Wales and in the north of England the population had declined sharply and only in the Scottish Highlands the population decline was relatively small. Irrespective of this, from 1951 onwards, heaps of broken eggs were found in peregrine falcon nests, which was previously practically unknown. After the discovery of the drastic collapse in populations, older peregrine falcon egg shells from egg collections in museums and from collectors were examined and a sudden decrease in egg shell thickness by an average of around 20% from 1947 onwards was found. Similar reductions in egg shell thickness have also been found in the UK in sparrowhawk and merlin .

    Catastrophic populations and a significant decline in egg shell thickness after 1950 were recorded simultaneously or only a little later in large parts of the northern hemisphere. In Europe, the peregrine falcon died out in Denmark , Poland, the Netherlands , Belgium , Luxembourg and the GDR by the end of the 1970s, the populations in Scandinavia , the Federal Republic of Germany , Switzerland and Austria declined except for a few pairs. The tree breeder population in Central and Eastern Europe died out completely. In the United States , the peregrine falcon disappeared from all states east of the Rocky Mountains .

    The sudden decrease in egg shell thickness after 1946 coincided with the years when DDT was first used on a large scale in agriculture and forestry. At the end of the 1960s it was found that the content of the DDT metabolite DDE (dichloro-diphenyl-dichloroethylene) in eggs correlates negatively with the thickness of the egg shell. A 17% decrease in egg shell thickness was associated with a DDE content of 15-20 ppm DDE based on the fresh weight of the egg content. Peregrine falcon populations, whose average eggshell thicknesses were reduced by 17% or more, fell sharply or died out.

    Due to its toxic effect on peregrine falcons and many birds of prey, DDT was banned in all western industrialized countries from the early 1970s. The remaining peregrine falcon populations increased sharply again from around the end of the 1970s, the recovery of the population was strongly promoted by the intensive protection of the breeding sites, with some of the breeding sites being guarded during the breeding season, and numerous reintroduction programs in many regions. Today almost all regions where peregrine falcons were at home before the so-called “DDT crash” are repopulated. In the course of this population recovery, the peregrine falcon has also colonized many cities, here the settlements are often intensively supervised by hatchery management. To this day, however, the southern half of Finland, the Baltic States, Belarus, Ukraine with the exception of Crimea and the western part of European Russia are uninhabited.

    After the low around 1975, the German population rose sharply again to around 50 pairs and comprised around 950 breeding pairs (BP) in 2006, around 250 BP in Austria again in 2004 and around 250 BP in Switzerland in 2002. The total European population at the beginning of the 21st century was estimated at around 6,600 BP. The peregrine falcon was bird of the year 1971 and thus the first species to be considered in this way.

    The IUCN estimates the total peregrine falcon population today at 10,000 to 100,000 animals and considers it stable. The species is classified as "not endangered".

    Peregrine falcons in cities

    Peregrine falcons have been breeding at the MetLife Building in New York since 1990
    Nesting peregrine falcon in a nesting basket on a telecommunications tower in the Sauerland

    Up until the 1980s, peregrine falcon broods on buildings were rare exceptions. The main cause before 1955 was the intense persecution, after 1955 the population collapse due to DDT. As a result of the “pesticide crash”, human attitudes towards the peregrine falcon changed fundamentally. In the course of the recovery of the stock from the mid-1970s, buildings in and outside cities were also settled. A variety of building types such as power plants, telecommunication towers, bridges, church towers and other tall buildings were chosen as breeding grounds. Even in operation bucket wheel excavators and skimmers in large opencast mines are brooding. These settlements have now been given intensive support, above all by installing suitable nesting aids. Peregrine falcons were also able to establish new populations in large rock-free areas. Especially in the lowlands, building breeders make up a considerable part of the total stock. In the east of the USA in 1993 about 34% of the population brooded in buildings, in the Midwest of the USA in 1995 over 80%, in North Rhine-Westphalia in 1996 also over 80%. In the Federal Republic of Germany in 2006 of the approx. 950 known couples a good 310 (= 33%) of buildings. The first pair brooded in the London area in 1998 and the number rose to 23 district pairs by 2010. The skyscraper landscape of Manhattan in New York City is considered to be the place of the highest density of breeding peregrine falcon pairs worldwide , where two falcon pairs first nested in 1983 on the Verrazzano-Narrows Bridge and the Throgs Neck Bridge . By 2016, the number of breeding pairs in the urban area had increased to 16. While adult peregrine falcons are hardly threatened in urban areas, many falcons that have just flown out have accidents here at technical obstacles, especially when they approach glass facades and fall into large chimneys. In Berlin, from 1986 to 1999, 34.3% of the young birds flown out did not survive until they became independent; In New York , too , the loss rate from 1983–1992 was around 33%.

    Peregrine falcon and human

    swell

    literature

    • R. Altenkamp, ​​P. Sömmer, G. Kleinstäuber & C. Saar: Population development and reproduction of the building-breeding peregrine falcons Falco p. peregrinus in Northeast Germany in the period 1986–1999. Vogelwelt 122, 2001: pp. 329–339
    • TJ Cade, JH Enderson, CG Thelander & CM White (Eds): Peregrine Falcon Populations - Their management and recovery . The Peregrine Fund, Boise, Idaho, 1988. ISBN 0-9619839-0-6
    • S. Frank: City Peregrines. Surrey, Blane, 1994.
    • Urs N. Glutz von Blotzheim , KM Bauer and E. Bezzel: Handbook of the birds of Central Europe . Volume 4, 2nd edition, AULA-Verlag, Wiesbaden 1989, ISBN 3-89104-460-7 .
    • T. Mebs and D. Schmidt: The birds of prey in Europe, North Africa and the Middle East . Franckh-Kosmos, Stuttgart, 2006. ISBN 3-440-09585-1
    • D. Ratcliffe: The Peregrine Falcon . 2nd Edition. Poyser, London, 1993. ISBN 0-85661-060-7 .
    • Ralendick: Falco p. peregrinus in Northeast Germany in the period 1986–1999. Vogelwelt 122, 2002: pp. 328–334

    Web links

    Commons : Peregrine Falcon ( Falco peregrinus )  - Album with pictures, videos and audio files
    Wiktionary: Peregrine falcon  - explanations of meanings, word origins, synonyms, translations

    Individual evidence

    1. Alerstam, T. (1987) Radar Observations of the Stoop of the Peregrine Falcon Falco Peregrinus and the Goshawk Accipiter Gentilis. Ibis, 129, 267-273. - References - Scientific Research Publishing. Retrieved November 2, 2019 .
    2. Peregrine falcon voice example
    3. ^ M. Wink, H. Sauer-Gürth, D. Ellis and R. Kenward: Phylogenetic relationships in the Hierofalco complex (Saker-, Gyr-, Lanner-, Laggar Falcon) . In: RD Chancellor & BU Meyburg (Ed.): Raptors Worldwide . World Working Group on Birds of Prey and Owls, Budapest, 2003: pp. 499-504
    4. ^ F. Nittinger, E. Haring, W. Pinsker, M. Wink and A. Gamauf: Out of Africa? Phylogenetic relationships between Falco biarmicus and the other hierofalcons (Aves: Falconidae) . Journal of Zoological Systematics and Evolutionary Research 43; 2005: pp. 321-331
    5. ^ A. Dixon, A. Sokolov & V. Sokolov: The subspecies and migration of breeding Peregrines in northern Eurasia. In: Falco , No. 39, pp. 4–9, 2012. (digitized version)
    6. Article in the Thüringische Landeszeitung from June 12, 2016
    7. P. Sömmer: The nutrition of the Berlin peregrine falcon breeding pair . Pica 16, 1989: pp. 120-128
    8. a b Altenkamp et al. 2001
    9. G. Speer & P. ​​Wolf: Wanderfalkenterzel is almost 18 years old. Ornithologische Mitteilungen 54, 2002: pp. 444–446
    10. z. BJ Heidemann: From the migration of the kestrel (Falco t. Tinnunculus), peregrine falcon (Falco peregrinus) and tree falcon (Falco s. Subbuteo). Der Vogelzug 6, 1935: pp. 11–26
    11. ^ MA Yates, KE Riddle and FP Ward: Recoveries of Peregrine Falcons migrating through the Eastern and Central United States, 1955–1985. In: Cade et al. 1988: pp. 471-483
    12. ^ DA Ratcliffe: The status of the Peregrine in Great Britain. Bird Study 10; 1963: pp. 56-90
    13. ^ DA Ratcliffe: Decrease in eggshell weight in certain birds of prey . Nature 215, 1967: pp. 208-210
    14. DB Peakall and LF Kiff: DDE contamination in Peregrines and American Kestrels and its effect on reproduction. In: Cade et al. 1988: pp. 337-351
    15. a b S. Kramer: From the rise of the building breeders . In: C. Saar: The return of the peregrine falcon , in preparation [1]
    16. ^ A b 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
    17. Cade, TJ, M. Martell, P. Redig, T. Septon & H. Tordoff: Peregrine Falcons in urban North America . In: DM Bird, DE Varland & JJ Negro (eds.): Raptors in Human Landscapes . London, San Diego; 1996: pp. 3-13
    18. HB Tordoff and PT Redig: Midwest Peregrine Falcon demography, 1982–1995 . J. Raptor Res. 31; 1997: 339-346
    19. ^ H. Brücher and P. Wegner: Re-colonization of North Rhine-Westphalia by the peregrine falcon (Falco peregrinus) - Current status and protection . In: Population ecology birds of prey and owl species 3, 1996: pp. 235–241
    20. Andrew Self: The Birds of London. Bloomsbury Publishing, London 2014, p. 142
    21. ^ Peregrine Falcons in New York City. NYC Department of Environmental Protection, accessed January 22, 2018 .
    22. ^ Mireya Navarro: Record Number of Peregrine Falcons in New York State. The New York Times, February 12, 2009, accessed January 22, 2018 .
    23. Frank 1994
    This version was added to the list of articles worth reading on November 18, 2007 .