Red-tailed black cockatoo

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Red-tailed black cockatoo
Red-tailed Black Cockatoos, pair. On the left the male who does not yet have the dark gray beak of adult males

Red-tailed Black Cockatoos, pair. On the left the male who does not yet have the dark gray beak of adult males

Systematics
Class : Birds (aves)
Order : Parrots (Psittaciformes)
Family : Cockatoos (Cacatuidae)
Genre : Black Cockatoos ( Calyptorhynchus )
Type : Red-tailed black cockatoo
Scientific name
Calyptorhynchus banksii
( Latham , 1790)

The Red-tailed Black Cockatoo ( Calyptorhynchus banksii ), also known as Banks Black Cockatoo, is a species of cockatoo that is part of the fauna of Australia . The five subspecies into which the species is usually divided differ mainly in the size of their beak. Two subspecies found in southern Australia are considered threatened.

Adult red-tailed black cockatoos reach a body length of 60 centimeters. There is a noticeable gender dimorphism . The basic color of the plumage of the males is black. On the outer control feathers, however, there is a wide, bright red band, which is sometimes also characterized by a narrow pale orange border area. The females are smaller. Their plumage has a brownish tinge on the underside of the body. The head and neck and wings have pale yellow spots on the ends of individual feathers. The outer control feathers have a wide yellow band.

Red-tailed black cockatoos are mostly found in eucalyptus forests and along watercourses. In the northern regions of Australia they form schools. They are seed-eaters and nest in tree hollows.

Surname

Red-tailed Black Cockatoo, flying

A female of the red-tailed black cockatoo was already drawn in 1770 by Sydney Parkinson , who worked for the British botanist Sir Joseph Banks . The female is believed to have come from the Endeavor River in northern Queensland. A scientific description was given in 1790 by the ornithologist John Latham as Psittacus banksii . With the specific epithet , John Latham wanted to honor Sir Joseph Banks.

Almost at the same time as John Latham, the English scientist George Shaw described a Psittacus magnificus based on a specimen hunted in the region of present-day Sydney . Gregory Mathews proposed in 1927 to use the name Calyptorhynchus magnificus for the species , since in his opinion George Shaw's description was the older. This suggestion was followed for several decades, although it was by no means certain that the specimen described by George Shaw was in fact a red-tailed black tailed cockatoo and not a brown-headed cockatoo . In 1994 the International Commission for Zoological Nomenclature accepted a proposal to name the species Calyptorhynchus banksii in the future.

The generic name Calyptorhynchus is derived from the ancient Greek. Calypto- / καλυπτο- stands for hidden and rhynchus / ρυγχος for beak. The name is a reference to a courtship gesture by the male in which the hood and cheek feathers are spread so far forward that the beak is no longer visible. The generic name was first proposed by Anselme Gaëtan Desmarest in 1826 .

Appearance

Appearance of adult birds

Young male. The tail feathers are not yet completely colored. Darling Scarp , Roleystone, Western Australia
Flying Red-tailed Black Cockatoo, Healesville Sanctuary

Red-tailed black cockatoos reach a body length of 60 centimeters when fully grown. They weigh 590 and 920 grams, depending on the subspecies. The subspecies Mathew's red-tailed black cockatoo is the lightest, with females weighing between 590 and 690 grams. The heaviest are the males of the nominate form , which can reach up to 920 grams.

The males are predominantly black in color. Their forehead and crown feathers are elongated and form a conspicuous hood. The control springs have the characteristic red transverse banding for the species. The beak is dark gray. The iris is dark brown. The legs are brownish gray.

The plumage of the females is also black. However, there is a brownish tinge on the underside of the body. Like the males, they have elongated forehead and crown feathers. Depending on the subspecies, the females have spots of different intensity on the head, neck and wings. In the nominate form, the outer control springs have wide yellow bands in the middle. On the inside of the flag these are pale yellow and become a more intense yellow-orange in the middle of the flag. The outer vane of the feathers has an orange-yellow band. The beak is horn-colored in the females.

In flight, red-tailed black cockatoos are easy to distinguish from other black cockatoos, because they constantly tilt to one side and then to the other. Their wing beats show a clear downward movement, so that their wings almost touch under the fuselage. They prefer high altitudes and slide down from above into the trees on which they want to settle.

Appearance of the young birds

Young red-tailed black cockatoos resemble the females until they reach sexual maturity. However, they are a little lighter on the underside of the body than the females. The change into the plumage of adult and sexually mature red-tailed black cockatoos takes the males over four years. While they hardly differ from females in the first year of life, they show a reduced number of yellow spots on the head and on the wing covers after the annual moult of the second year. The banding on the chest plumage decreases. The transverse bands on the control springs become wider and have a higher proportion of red. The beak becomes darker. In the third year of life, young males have only a few yellow spots in their plumage. The narrow black horizontal stripes in the red band of the control springs have largely disappeared. In the fourth year of life, the young males have shiny black body plumage and a uniform red band on the control feathers. The beak has then turned a gray-black color.

Vocalizations

The red-tailed black cockatoo has only a small repertoire of calls. During the flight he calls out a metallic rolling krur-rr or kree , which can be heard from afar . The alarm call is a sharp, yelling krur-rak , which is clearly different from the closely related brown-headed cockatoo. Courting males let out a rhythmic kred-kred-kred-kred . Begging young birds squeak but make no sounds when they are fed.

Distribution and existence

Distribution map of the Red-tailed Black Cockatoo

The red-tailed black cockatoo is found mainly in the north and northeast of Australia. In these tropical and subtropical zones, this species is so common in places that it is considered an agricultural pest. In the interior and in the southern regions of Australia, this cockatoo species is only represented with isolated populations. In Western Australia, feral domestic cats in particular have significantly reduced populations.

The entire population of red-tailed black cockatoos is not considered endangered. Overall, it is assumed that there are more than 100,000 individuals. However, the size of the distribution area has decreased and the population of southern red-tailed black cockatoo is estimated at only 1,000 individuals. In the north of New South Wales and in southeast Queensland the nominate form no longer occurs. The subspecies of the southern red-tailed black cockatoo is strongly dependent on the three tree species Eucalyptus baxteri , Eucalyptus camaldulensis and Allocasuarina luehmannii . These trees are threatened by reclamation and are now predominantly found on privately owned areas. There may only be 500 to 1,000 trees left that could be used as nesting trees for this subspecies. For the subspecies and its habitat, however, there is a protection program that reimburses landowners in 2007 if they help to preserve suitable habitats for this subspecies.

habitat

Western Australian Red-tailed Black Cockatoo

The preferred habitat of these cockatoo species are savannahs and gallery forests with eucalyptus trees that stretch along the rivers. However, they are adaptable and use a wide range of different habitats. In addition to dense eucalyptus forests, with acacia and allocasuarina savannas, this also includes monsoon rainforests and subtropical rainforests , shrubland with silver trees, grass savannas and agricultural areas that still have a certain population of older trees.

Bank cockatoos are basically part migrants, which show a regular migratory movement in different regions of Australia. In the north of the Northern Territory , they move away when the humidity rises sharply during the summer . In other regions, the seasonally fluctuating food supply is the reason why red-tailed cockatoos migrate to other regions. Such behavior can be observed, for example, in northern Queensland and New South Wales. In the southwest of Western Australia, the two subspecies found there show a north-south directed migratory movement. The Western Australian Black Cockatoo migrates north after the breeding season, while the Mathews Red-tailed Black Cockatoo migrates somewhat more erratically and has no correlation with the season.

behavior

Red-tailed black cockatoos are diurnal and noisy cockatoos. However, they are also active on moonlit nights. Especially in northern Australia they can be observed in swarms that consist of up to 500 individuals. Such large swarms do occur in the south of Australia when there is adequate food. Here, however, they typically live in pairs or form a small family group consisting of the parent birds and a young bird. In the north and northeast of Australia, Red-tailed Black Cockatoos often forage on the ground and are particularly noticeable in areas burned down by bushfires. They are primarily looking for the seeds of Hakeas and Banksien , the hard-shelled fruits of which have opened due to the effects of heat. The two subspecies occurring in the south of Australia, the southern and western red-tailed black cockatoo, on the other hand, avoid staying on the ground if they can also be observed in cattle troughs when drinking water.

food

Red-tailed black cockatoo while eating
6 week old red-tailed black cockatoo

Red-tailed cockatoos prefer to eat the seeds of eucalyptus trees. They prefer the species that carry medium-sized to large seeds. The red-tailed black cockatoos usually bite off the entire fruit cluster, hold it with one foot and then bite off the base of a seed pod with its beak. They also occasionally seek out the ground to pick up pieces of food that have fallen there. The seeds of acacia, allocasuarina, hakea and banksias are also part of their diet . They also eat nuts, fruits, berries, nectar, flowers and insects and their larvae. The fruits of figs and screw trees are also part of their diet. In addition, they eat some of the plant species introduced to Australia . These include field radish , melons and cucumbers.

Reproduction

The breeding season of the red-tailed black cockatoo falls mainly in the months May to September. Only the subspecies found in the southeast nest during the Australian summer months from December to February. The subspecies Mathew's red-tailed black cockatoo occasionally broods twice a year.

The male red-tailed black cockatoo's courtship repertoire includes raising the bonnet. This then leans forward to the upper beak. The feathers of the cheek region are spread far forward so that they cover the beak. The control springs are fanned out so that the red cross straps are clearly visible. In a stiff posture, he walks along the branches and then bows to the female. This often reacts aggressively to the advances of the male and initially bites at the courting male.

Red-tailed cockatoos use knotholes or hollow trunks of living and dead trees as nesting holes. Most of the nesting holes are in somewhat isolated trees so that the parent birds can reach the nesting hole relatively unhindered. Individual nest holes are often used over many years. The caves have a depth of one to two meters and a diameter of up to half a meter. Usually an egg is simply laid on the floor of the cave. There are clutches of two eggs, but usually one of the young is neglected and dies before it can fledge. The eggs are elliptical to elliptical-egg-shaped and have a dull white surface. The foundation of the nest is the rotting wood at the bottom of the cave. The female breeds alone. The incubation period is 30 days. The newly hatched nestling is covered with long yellow dunes. The eyes first open at two to three weeks of age. The first three weeks of the nestling by the female brooded . During this time, the male provides the female and nestling with food. After the first three weeks, the nestling is only fledged by the female at night. The young bird leaves the nest at around three months. During the next four months he will be looked after by the parent birds.

Like many other species of cockatoo, the red-tailed black cockatoo is very long-lived. In 1938 ornithologist Neville Cayley reported on a red-tailed black cockatoo over fifty years old that lived in the Taronga Zoo in Sydney .

Systematics

Female of the Mathews Red-tailed Black Cockatoo subspecies, Whicher Range National Park, Western Australia

The genus Calyptorhynchus is a group of black cockatoos with large and powerful beaks. The genus is divided into two sub-genera based on the different beak shapes and the clear differences in sex dimorphism. Most species are assigned to the subgenus Zanda . The red-tailed black cockatoo belongs together with the brown-headed cockatoo to the subgenus Calyptorhynchus . Both species show a very pronounced sexual dimorphism. Adult males are pure black with a red tail band. The females as well as the not yet sexually mature young birds have yellow to orange-red colored tail bands. Both species are characterized by a very broad and beak. Further characteristic features of this subgenus are the squeaking feed-bed noises of the boys and the lack of noises when swallowing the food. There are five subspecies, two of which are classified as endangered. The individual subspecies mainly differ in body size, size and shape of the beak and the color of the female.

subspecies Distribution area Distinguishing features of the individual subspecies
C. b. banksii ( Latham , 1790), nominate form Queensland , more rarely in the far north of New South Wales The nominate form is the largest subspecies and has a medium-sized beak
Southern red-tailed black cockatoo

( S. b.graptogyne Schodde , Saunders, DA & Homberger , 1989)

Southwest Victoria and Southeast South Australia The smallest subspecies with more conspicuous markings than the otherwise similar Mathews red-tailed black cockatoo. It wasn't until the 1980s that S. b. graptogyne recognized as an independent subspecies. The subspecies is considered to be critically endangered.
Gould's red-tailed black cockatoo ( C. b. Macrorhynchus Gould , 1843) The northwest of Australia from the Dampierland in the northwest of Western Australia to the Gulf of Carpentaria in the northeast of the Northern Territory. Very similar to the nominate form, but with a broader and more powerful beak. The spots of the body plumage as well as the horizontal stripes of the outer control feathers are pale yellow in the female.
Western Australian Red-tailed Black Cockatoo ( C. b. Naso Gould , 1837) In the extreme southwest of Western Australia between Perth and Albany Critically endangered small subspecies with pointed wings and a rather rounded hood. In the female, the tail band is strikingly orange. Compared to the Mathews red-tailed black cockatoo, this subspecies has a longer and wider beak.
Mathews red-tailed black cockatoo ( C. b. Samueli Mathews , 1917) Four isolated populations in the coastal region of central Western Australia , along the river system of the Central Australian mountain ranges, along the main and tributaries of Lake Eyre and in the catchment area of ​​the Bulloo River, as well as along the upper and middle reaches of the Darling River system in western New South Wales. The subspecies is colored like the nominate form, but significantly smaller and the beak is less bulky.

Red-tailed Black Cockatoo and human

Protective measures

The red-tailed black cockatoo is a protected species under the Australian Environment Protection and Biodiversity Conservation Amendment (Wildlife Protection) Act 2001 . It is also listed in Appendix II of the CITES agreement. This allows cross-border trade in wild-caught species and species reared in captivity, provided that the export does not have a negative impact on the wild population. However, the stricter Australian regulations apply, so that no export is taking place at the moment.

The red-tailed black cockatoo population is valued differently depending on the Australian state:

  • The southern red-tailed black cockatoo is considered an endangered subspecies according to the requirements of the "National Parks and Wildlife Act (1972)".
  • The same subspecies is classified as critically endangered under the Flora and Fauna Guarantee Act (1988) of the Australian state of Victoria. Measures for the preservation of the subspecies are developed according to the regulations.
  • Regardless of the subspecies, the red-tailed black cockatoo is considered an endangered species in New South Wales

Keeping in human care

Red-tailed cockatoos are rarely kept in aviaries. They were imported to Europe several times at the end of the 19th and the beginning of the 20th century. Since the Australian government banned the export of all species of Australian fauna, aviary populations have been falling in Europe and North America.

supporting documents

Individual evidence

  1. ↑ a b Forshaw, p. 108.
  2. ^ John Latham: Index ornithologicus, sive Systema Ornithologiae; complectens avium divisionem in classes, ordines, genera, species, ipsarumque varietates: adjectis synonymis, locis, descriptionibus, & c. : Vol. 1 & 2 xviii 920 . Leigh & Sotheby, London 1790, OCLC 9637593 , p. 107 .
  3. ^ Ian Rowley: Handbook of the Birds of the World - Volume 4: Sandgrouse to Cuckoos . Ed .: J. del Hoyo, A. Elliott, J. Sargatal. Lynx Edicions, 1997, ISBN 84-87334-22-9 , Cacatuidae.
  4. ↑ a b Lendon, p. 64.
  5. ↑ R. Schodde, W. Bock: Case 2856. Psittacus banksii Latham, 1790 and P. lathami Temminck, 1807 (currently Calyptorhynchus banksii and C. lathami ; Aves, Psittaciformes): proposed conservation of the specific names . In: Bulletin of Zoological Nomenclature . tape 51 , no. 3 , 1994, p. 253-255 .
  6. ^ Henry George Liddell, Robert Scott: Greek-English Lexicon, Abridged Edition . Oxford University Press, Oxford 1980, ISBN 0-19-910207-4 .
  7. ↑ Anselme Gaëtan Desmarest: Perroquet . Dictionnaire des Sciences Naturelles dans lequel on traite méthodiquement des différens êtres de la nature, considérés soit en eux-mêmes, d'après l'état actuel de nos connoissances, soit relativement à l'utilité qu'en peuvent retirer la médecine, l ' agriculture, le commerce et les arts. Suivi d'une biography of the plus célèbres naturalistes. Par plusieurs Professeurs du Jardin du Roi, et des principales Écoles de Paris. FG Levrault, Strasbourg 1826, OCLC 4345179 , p. 21, 117 .
  8. ^ Forshaw, pp. 104 - 107.
  9. ↑ a b c d Forshaw, p. 104.
  10. ↑ a b c d e Forshaw, p. 115.
  11. ↑ a b Hoppe, p. 83.
  12. ↑ Lendon, p. 66
  13. ^ Forshaw, p. 119.
  14. ^ A b c J. Courtney: The juvenile food-begging calls, food-swallowing vocalization and begging postures in Australian Cockatoos . In: Australian Bird Watcher . tape 16 , 1996, pp. 236-249 .
  15. ^ TK Lim, L. Bowman, S. Tidemann: A report on the survey of winged vertebrate pest damage on crops in the Northern Territory . In: Technical bulletin (Northern Territory. Dept. Of Primary Industry and Fisheries) . No. 209 , 1993.
  16. ↑ Felis catus . In: Database of the "100 of the World's Worst Invasive Alien Species" of the "Invasive Species Specialist Group" of the IUCN, accessed on May 30, 201.
  17. ↑ a b website parrots, accessed on March 27, 2009
  18. ^ L. Joseph: The Red-tailed Black-Cockatoo in south-eastern Australia . In: Emu . tape 82 , no. 1 , 1982, pp. 42-45 ( csiro.au ).
  19. ↑ L. Joseph, WB Emison, WM Bren: Critical assessment of the conservation status of the Red-tailed Black-Cockatoo in south-eastern Australia with special reference to nesting requirements . In: Emu . tape 91 , no. 1 , 1991, p. 46-50 ( csiro.au ).
  20. ↑ Landholders rewarded for helping save red tailed black cockatoo ( Memento from June 10, 2008 in the Internet Archive ) In: ABC Southwest Victoria. Australian Broadcasting Corporation, April 4, 2007.
  21. ^ GM Storr: Birds of the Northern Territory (=  Special publications of the Western Australia Museum . Volume 7 ). Western Australia Museum, Perth 1977, ISBN 0-7244-6281-3 .
  22. ^ JA Bravery: The birds of the Atherton Shire, Queensland . In: Emu . tape 70 , 1970, pp. 49-63 .
  23. ↑ HB Gill: Birds of Innisfail and Hinterland . In: Emu . tape 70 , 1970, pp. 105-116 .
  24. ^ JR Ford: New Information on the distribution of birds of south-western Australia . In: The Western Australian Naturalist . tape 10 , no. 1 , 1965, p. 7-12 .
  25. ↑ Eric H. Sedgwick: Bird movements in the wheatbelt of Western Australia . In: The Western Australian Naturalist . tape 2 , no. 2 , 1949, p. 25-33 .
  26. ↑ a b c Forshaw, p. 113.
  27. ^ DA Saunders, I. Rowley, GT Smith: Birds of Eucalypt Forests and Woodlands: Ecology, Conservation, Management . Ed .: A. Keast, HF Recher, H. Ford, DA Saunders. Surrey Beatty, Chipping Norton 1985, ISBN 0-949324-06-X , The effects of clearing for agriculture on the distribution of cockatoos in the southwest of western Australia, pp. 309-321 .
  28. ^ DA Saunders: Red-tailed Black-Cockatoo breeding twice a year in the south-west of Western Australia . In: Emu . tape 77 , no. 3 , 1977, pp. 107-110 ( csiro.au ).
  29. ↑ WB Emison, CM White, WD Caldow: Presumptive Renesting of Red-tailed Black-Cockatoos in South-eastern Australia . In: Emu . tape 95 , 1995, pp. 141-144 .
  30. ^ Forshaw, p. 116 and p. 117.
  31. ↑ Gordon Beruldsen: Australian Birds: Their Nests and Eggs . G. Beruldsen, Kenmore Hills 2003, ISBN 0-646-42798-9 , pp. 240 .
  32. ^ Forshaw, p. 118.
  33. ↑ Lendon, p. 68.
  34. ^ Forshaw, p. 66.
  35. ↑ a b c Peter Jeffrey Higgins: Handbook of Australian, New Zealand and Antarctic Birds . Volume 4: Parrots to Dollarbird . Oxford University Press, Melbourne 1999, ISBN 0-19-553071-3 .
  36. ^ R. Hill, T. Burnard: A Draft Habitat Management Plan for the South-eastern Red-tailed Black-Cockatoo. Unpublished report to the Red-tailed Black-Cockatoo Recovery Team, 2001.
  37. ^ J. Ford: Morphological and ecological divergence and convergence in isolated populations of the Red-tailed Black-Cockatoo . In: Emu . tape 80 , no. 3 , 1980, p. 103-120 .
  38. ^ R. Schodde: New subspecies of Australian birds . In: Canberra Bird Notes . tape 13 , no. 4 , 1988, pp. 119-122 .
  39. ↑ a b Hoppe, p. 81.
  40. ↑ Hoppe, p. 82.
  41. ^ Forshaw, p. 106.
  42. ^ A b Environment Protection and Biodiversity Conservation Amendment (Wildlife Protection) Act 2001. In: Commonwealth of Australia Law. Australian Government: Attorney-General's Department, July 11, 2001, accessed September 5, 2007 .
  43. ^ T. Inskipp, HJ Gillett: Checklist of CITES Species. (PDF; 2.2 MB) (No longer available online.) Convention on International Trade in Endangered Species of Wild Fauna and Flora, 2003, p. 84 , archived from the original on September 30, 2007 ; Retrieved August 24, 2007 .
  44. ↑ NATIONAL PARKS AND WILDLIFE ACT 1972 - SCHEDULE 7 National Parks and Wildlife Act 1,972th
  45. ↑ Flora and Fauna Guarantee Act - Listed Taxa, Communities and Potentially Threatening Processes. ( Memento of December 6, 2010 in the Internet Archive ) Department of Sustainability and Environment, Victoria
  46. ^ Flora and Fauna Guarantee Act: Index of Approved Action Statements. ( Memento of July 23, 2008 in the Internet Archive ) Department of Sustainability and Environment, Victoria
  47. ^ Victorian Department of Sustainability and Environment: Advisory List of Threatened Vertebrate Fauna in Victoria - 2007 . Department of Sustainability and Environment, East Melbourne, Victoria 2007, ISBN 978-1-74208-039-0 , pp. 15 .
  48. ↑ Hoppe, p. 87.

literature

  • Joseph M. Forshaw, William T. Cooper: Australian Parrots . 3. Edition. Alexander Editions, Robina 2002, ISBN 0-9581212-0-6 .
  • Jim Flegg: Birds of Australia: Photographic Field Guide . Reed New Holland, Sydney 2002, ISBN 1-876334-78-9 .
  • Dieter Hoppe: Cockatoos - way of life, keeping and breeding. Eugen Ulmer Verlag, Stuttgart 1986, ISBN 3-8001-7155-4 .
  • Alan H. Lendon: Australian Parrots in Field and Aviary . Angus & Robertson, 1973, ISBN 0-207-12424-8 .
  • Stephen Garnett: Threatened and Extinct Birds Of Australia . (= RAOU. 82). Royal Australasian Ornithologists Union, Moonee Ponds, Vic. 1992, ISBN 0-00-812801-4 .

Web links

Commons : Calyptorhynchus banksii  - Collection of images, videos and audio files