Yellow-eared Black Cockatoo

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Yellow-eared Black Cockatoo
Black Cockatoo, male

Black Cockatoo, male

Systematics
Class : Birds (aves)
Order : Parrots (Psittaciformes)
Family : Cockatoos (Cacatuidae)
Genre : Black Cockatoos ( Calyptorhynchus )
Type : Yellow-eared Black Cockatoo
Scientific name
Calyptorhynchus funereus
( Shaw , 1794)
Distribution area of ​​the black cockatoo in Australia
Black cockatoo tearing off tree bark
Flying Yellow-eared Black Cockatoo. The yellow transverse band on the outer control springs can be seen very clearly

The black cockatoo ( Calyptorhynchus funereus ) is a cockatoo species . It occurs exclusively in Southeast Australia and can also be observed in Tasmania. This species is one of the largest cockatoos. Yellow-eared Black Cockatoos have adapted well to humans and are also often seen in the metropolitan area of Sydney and Melbourne .

Although the species is not very common, it is not considered threatened. They are found in different frequencies within their range. They may be completely absent for years in areas where it was previously frequent, but then reappear there.

As a very conspicuous bird, the black cockatoo belongs to the character species of the avifauna of southeastern Australia. Their flight is particularly noticeable. They do fly at high altitudes when they cover greater distances. However, when they change location slightly, they fly at a lower altitude. Their wide flapping wings are very slow and they constantly let out contact calls. Their loud calls are characteristic, so that the species is considered unmistakable.

Appearance

Black cockatoos reach a body length of 65 centimeters and have a body weight of 600 to 840 grams. Together with the Banks Black Cockatoo , they are the largest species of parrot in Australia's fauna .

Male black cockatoos have brownish black body plumage. The underside of the body is a little more matt and brownish. The neck and belly feathers have a very narrow, yellowish feather edge, so that their body plumage appears scaly. The ear covers are strikingly yellow. The outer control feathers have a wide yellow band in the rear half of the tail. The dark gray beak is narrow and protruding and has pointed ends. The iris is dark brown. They have a featherless, flesh-colored eye ring. The legs are grayish brown.

The gender dimorphism is only slightly pronounced. In females, only the yellow color of the ear covers is more noticeable. The yellow feather hems are a little more pronounced. The outer tail feathers are dotted a bit more brownish-black on the outside flags both on the upper and lower sides. The beak is horn-colored and the featherless eye ring is gray-black.

habitat

Yellow-tailed Black Cockatoos are cave breeders that rely on large, old trees. But they are otherwise adaptable and use all forested forms of vegetation within their area of ​​distribution. These include rainforest, high mountain and mountain forest, open woodland and tree-covered pasture land with rivers and streams running through it. Beyond their reproductive period are also to be found in lined with shrub vegetation coast and also use banksia -Savannen. They also use urban habitats and can be found in city parks, gardens and golf courses.

Behavior and food

Black cockatoos live in pairs or in small family groups consisting of the two parent birds and a young bird and are occasionally found in small flocks. Larger accumulations mainly occur when the fruits of banksias and screw trees open after bushfires . They then also stay on the ground to take in food there. They are diurnal birds that leave their sleeping trees in the morning and move to the places where they can find sufficient food. As a rule, tall eucalyptus trees serve as sleeping trees.

Yellow-eared Black Cockatoos feed on seeds as well as insect larvae. Her food spectrum also includes grass seeds, nuts, berries, fruits, nectar, flowers and flower buds. They also gnaw the cones of the pines introduced into Australia. The pointed ends of their beak allow them to pick insect larvae from hard and woody seeds. But they also tear off bark to get to wood-boring larvae or dig with their beaks in the earth to get to larvae that live in the lateral roots of saplings. Black cockatoos can cause considerable damage in tree plantations through their feeding behavior. Young trees in particular are so damaged that they break in strong winds. They are also feared on apple orchards. They only eat the kernels of the apples and tear the pulp to get to the apple casing.

Evidence suggests that there are seasonal migrations in black cockatoos. However, this involves very small-scale changes in location. The cockatoo can therefore be regarded as a resident bird .

Reproduction

Black cockatoos are basically monogamous , the pair bond is long-term. The courtship behavior of the Black Cockatoo is relatively simple in structure. The males slowly bring the body into a horizontal hood, then spread the head plumage including the short hood feathers and fan the tail feathers so that the yellow tail band is clearly visible. With increasingly intense courtship, the male lowers his head more and more and at the same time straightens the tail. He spreads his wings. The male also feeds the female during courtship.

For breeding, black cockatoos prefer eucalyptus trees. Research has shown that they generally choose old trees as their breeding trees. The mean age of the breeding trees in a survey in southeast Victoria averaged 221 years. The entrances to the breeding caves are located at a considerable height. In the study carried out in Victoria, they were on average 36.7 meters above the ground.

The clutch usually consists of two eggs. However, usually only one nestling is raised. If a nestling does hatch from the second egg, it is usually so neglected by the parent birds that it dies very soon. The female breeds alone. The breeding season is 29 to 30 days. The nestlings are initially naked and have closed eyelids. These only open at around three weeks of age. The young bird fledged in the 12th to 13th week of life. However, it is fed by both parent birds for another three to four months.

Black cockatoos are sexually mature at around four years of age.

Systematics

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 . This also applies to the black cockatoo. The narrow and protruding beak is characteristic of all black cockatoos of this subgenus group.

The number of subspecies that must be distinguished for the black cockatoo is debatable. The ornithologist Joseph M. Forshaw , who specializes in parrots, distinguishes two subspecies

subspecies Distribution area Distinguishing features of the individual subspecies
C. f. funereus , nominate form The distribution area extends from central Queensland over eastern New South Wales to the east of the Australian state of Victoria The nominate form is the largest subspecies and has a slightly longer tail
Tasmanian black cockatoo

( C. f. Xanthanotus )

Tasmania and the larger islands of the Bass Strait Smaller than the nominate form with a significantly shorter tail. In the male, the yellow fringes of the body feathers are more pronounced.

Black Cockatoo and human

The keeping of black cockatoos was rare until the 1950s and is now largely restricted to Australia. Australian legislation largely prohibits the export of Australian species.

In Germany, black cockatoos were shown for the first time in Berlin in 1880. The Walsrode Bird Park and the Berlin Zoological Garden are among the few German zoos that have occasionally shown Black Cockatoos .

Black cockatoos are considered adaptable fosterlings, but they can only be kept in very large aviaries. The world's first breeding succeeded only in the late 1980s.

supporting documents

Individual evidence

  1. ^ Forshaw, p. 67.
  2. Hoppe, p. 94.
  3. Hoppe, p. 94.
  4. ^ Forshaw, p. 69.
  5. Hoppe, p. 95.
  6. ^ Forshaw, p. 71.
  7. Hoppe, p. 96.
  8. ^ Forshaw, p. 76.
  9. ^ Forshaw, p. 75.
  10. ^ Forshaw, p. 75.
  11. Hoppe, p. 95.
  12. ^ Forshaw, p. 72.
  13. Hoppe, p. 97.
  14. ^ Forshaw, p. 77.
  15. ^ Forshaw, p. 77.
  16. ^ Forshaw, p. 78.
  17. ^ Forshaw, p. 79.
  18. ^ Forshaw, p. 66.
  19. Hoppe, p. 98.
  20. ^ Forshaw, p. 79.

literature

  • Joseph M. Forshaw , illustrated by William T. Cooper: Australian Parrots. 1st German-language edition. Volume 1: Cockatoos and Lories. Arndt-Verlag, Bretten 2003, ISBN 978-3-9808245-1-4 .
  • Dieter Hoppe: Cockatoos - way of life, keeping and breeding. Eugen Ulmer Verlag, Stuttgart 1986, ISBN 3-8001-7155-4 .

Web links

Commons : Black Cockatoo ( Calyptorhynchus funereus )  - Collection of images, videos and audio files