Inca cockatoo
| Inca cockatoo | ||||||||||
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Inca Cockatoo ( Cacatua leadbeateri ) |
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| Systematics | ||||||||||
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| Cacatua leadbeateri | ||||||||||
| ( Vigors , 1831) |
The Inca cockatoo ( Cacatua leadbeateri ) belongs to the cockatoo family . It occurs with two subspecies in Australia . Its main distribution area is native to New South Wales and Victoria . Because of its conspicuously cross-banded feather bonnet and pink body plumage, many parrot lovers consider it the most beautiful of the cockatoos and one of the most beautiful parrots of all.
Unlike the pink and bare-eyed cockatoos , the Inca cockatoo has not benefited from the increasing number of livestock watering systems in the Australian pasture industry. Inca cockatoos are sensitive to deforestation and have disappeared in many agricultural areas, even if the remaining forest islands still offer sufficient habitat for other cockatoo species. The Inkakakatu is fully protected in all Australian states because of its declining numbers.
Appearance
Inca cockatoos reach a height of 35 centimeters and weigh between 365 and 425 grams. They are relatively small cockatoos. Its most distinctive feature is the multi-colored hood that is curved forward. It is limited by elongated front springs. The wings are wide and round. The horn-colored beak is proportionally small for a cockatoo.
The crown and the elongated forehead feathers are white. The elongated hood feathers are salmon-colored to pink at their feathers, darken towards the middle and are almost scarlet. They are interrupted by a narrow yellowish band and end in a broad white point. The head, the underside of the body and the under wing coverts are predominantly dusky pink. The small under wing coverts, the lower abdomen, the upper side of the body and the inner control feathers are white. The outer balance springs and the control springs are predominantly white. However, they are also pale old pink towards the base of the nib and on the underside of the interior colors. The iris is dark brown. The featherless eye ring is whitish; the toes are gray in color. The females are colored like the males, the yellow stripe in the feather bonnet is usually a bit wider. The female iris is more of a reddish-brown color. Young birds not yet sexually mature are similar to adult birds, but their irises are brown.
Inca cockatoos have a slow, deliberate-looking flight with flat, flapping wings. The flight is repeatedly interrupted by short gliding phases. They rarely fly at high altitudes. Even longer distances are usually made with short flights from tree to tree. During the flight, the spring hood is tightly fitted. When landing, however, it is spread apart. During the flight, the undersides of the body are particularly noticeable, which glow in different shades of red depending on the position of the sun. The contact call that can be heard from flying Inca cockatoos is a three-syllable, trembling kriiiek-kri-kriiiee . You shout this sound about a minute apart. If Inca cockatoos are concerned, the interval between the calls is shortened.
Distribution area
Incan cockatoos are common in the arid and semi-arid interior of Australia. The nominate form Cacatua leadbeateri leadbeateri occurs from southwest Queensland and the west of New South Wales to the northwest of the Australian state of Victoria and the middle east of South Australia. The subspecies Cacatua leadbeateri molli , which differs from the nominate form mainly in that the yellow band of the feather bonnet is narrower or even absent, occurs in the western and central interior of Australia.
Depending on the availability of food and water, flocks of Incan Cockatoo exhibit migratory movements. These are particularly pronounced in flocks made up of not yet sexually mature young birds and non-breeding adults. On average, they move over an area of 300 square kilometers. In the case of prolonged periods of drought, these migrations expand. The swarms tend to get bigger. During this time they occasionally penetrate into regions in which they normally do not occur.
habitat
Inca Cockatoos use a wide range of tree-covered habitats in arid and semi-arid zones. They prefer habitats with either callitris and eucalyptus or those with allocasuarina and eucalyptus. But they can also be found in regions with acacia scrub and grasslands with little tree cover. Access to fresh water is the limiting factor in their distribution in many regions.
Inca Cockatoos initially benefited from the colonization of the Australian continent by European settlers. The installation of cattle troughs, in which fresh water could be found all year round, initially meant that their number could increase. However, the deforestation of the tree population that goes along with the settlement has canceled this effect and in many places has led to a decline in the population of Incan cockatoos. This distinguishes them from other Australian cockatoos such as the pink cockatoo and the naked-eyed cockatoo . Both of these species can survive well on small, scattered forest islands in the middle of agricultural areas. While pink cockatoos breed semi-colonial and accept a small nesting cavity distance, Incan cockatoos do not breed in close proximity to each other. However, they go looking for food in social associations. They are therefore withdrawing from largely land-adjusted regions. Some ornithologists also suspect that Inca cockatoos, which usually cover long distances by short flights between groups of trees, have also disappeared from heavily agricultural regions because they avoided flights over open, treeless land.
behavior
The smallest social unit of the Inca Cockatoos is a couple. Incan cockatoos, like many other cockatoos, are monogamous. Once a couple bond has been entered into, it usually only ends with the death of one of the partners. Inca cockatoos also have a social bond with other conspecifics. With Inca cockatoos this is undoubtedly looser than, for example, with pink cockatoos, which breed semi-colonial and where the distance between the nesting holes is on average around 50 meters. In the Incakatoos, this distance is significantly greater. Nevertheless, Incan Cockatoos prefer to search for food in schools. They even sometimes ignore suitable feeding grounds near their nesting caves and fly several kilometers to team up with other Incan cockatoos. Investigations on the periphery of the Wheatbelt region in Western Australia have shown that swarms, which are made up of established breeding pairs, are relatively loyal to their place and return to the same foraging grounds over the years. Flocks made up of young, not yet sexually mature Inca Cockatoos and non-breeding adult cockatoos are more mobile. Both swarms also occasionally combine and then lead to the swarms comprising several hundred individuals that are occasionally observed. The largest recorded swarm of Incan cockatoos comprised 530 Incan cockatoos. He was observed on July 15, 1978 near Pink Lake State Park in the northwest of the Australian state of Victoria . The cockatoos came there together with pink cockatoos to eat Cucumis myriocarpus , a species of melon introduced in Australia . As a rule, however, flocks of more than forty or fifty animals are considered unusually large.
Inca cockatoos are diurnal birds. Outside the breeding season, they spend the night together in their swarm near the feeding grounds. Your food intake peaks in the first few hours after sunrise. They spend the hottest hours of the day in the treetops, where they take shelter from the sun in the shade of the foliage. Mated Inca cockatoos often sit very close together and nibble at each other's plumage. Unmated birds keep a distance of about 20 to 30 centimeters from the closest conspecifics. It is also typical of Inca Cockatoos that they are extremely aggressive within their fodder swarm and defend their food against other species. The hood springs are set up again and again.
Incan cockatoos are not quite as playful as pink cockatoos. But they also show playful behavior such as quick flights through brewer's crowns or through trees. They have a guard system. In a flock of birds, at least one bird observes the environment. Raising the hood often expresses the mood. It is resisted when both partners greet each other, when he wants to clarify the title to a cave or when the bird is worried. Like many other cockatoos, Inca cockatoos also spread their hoods when they land at their destination.
food
The food spectrum of the Inca Cockatoos includes grass seeds and seeds of herbaceous plants, nuts, fruits, berries, flowers, roots, leaf buds as well as insects and their larvae. The proportion of food that Incan cockatoos find on trees is greater than that of the pink and bare-eyed cockatoos. Incan Cockatoos also like to look for grains of wheat on harvested fruits. But they also like to look for ripe wheat fields that have not yet been harvested and can then cause considerable damage. Basically, the spectrum of food plants, the Incan Cockatoo, is very large compared to other cockatoo species. With their very powerful beaks, they are also able to break open the hard-shelled fruits of the screw trees . They also break the branches of eucalyptus and acacia trees to get at wood-boring insects.
Reproduction
The females of the Inca cockatoos usually lay eggs for the first time in their second year of life. However, the bond with a partner begins after the first year of life and usually takes place within the flocks of migrating young birds. Males are usually reproductive in their third year of life.
Incan cockatoos are cave breeders. What is unusual for cockatoos is the great distance between the nesting hole and the next. The average distance is 2.4 kilometers. In the more closely examined areas, the breeding caves were always at least one kilometer apart. The research also suggests that Inca cockatoos are very picky about nesting trees. Almost all of the nest cavities examined were at least one meter deep and each nest cavity was at least eight meters above the ground. The bottom of the nest hole is usually covered by a layer of wood pieces between three and five centimeters thick.
Incan cockatoos compete with a number of other cockatoo species for suitable nesting holes. Pink cockatoos are particularly strong competitors for nesting sites. Occasionally there are mixed spots between the two species, in which the larger Inca Cockatoos prevail. There are a number of cases in which a pink cockatoo was brought up in the clutch of an inca cockatoo.
The breeding season usually falls between August and December. Clutches include between one and five eggs. The breeding season is 23 to 24 days. Both parent birds breed. Young birds leave the nest at around 57 days. The young birds that have just fledged are first fed by their parents near the nest box until all the young birds have left the nest box. They then go to the different feeding places together. As soon as the young birds have fledged, they form flocks with other, not yet sexually mature young birds.
Systematics
Nicholas Aylward Vigors gave this cockatoo species the specific epithet leadbeateri in its first scientific description in order to honor the natural produce dealer Benjamin Leadbeater . Benjamin Leadbeater supplied the British Museum of Natural History with his natural produce store, founded in 1800, and wrote some ornithological reports himself.
The classification of the Inca cockatoo in the genus of the actual cockatoo is controversial. They have a number of characteristics that set them apart from the rest of the cockatoo species. The nestlings are much less covered with primary down than in the other species. The downs are also arranged along two back strips. The begging movement of the nestlings also differs from that of the other species. With them the begging movement is directed forwards and not to the side. Inca cockatoos are therefore occasionally placed in the subgenus Lophocroa . However, it is also discussed that they should be classified in their own genus, like the pink cockatoos, which are closely related to them .
Human and Inca Cockatoo
Inca cockatoos are demanding fosterlings. Even hand-raised, they rarely become tame and do not develop a close bond with their caretaker. They are also very noisy birds. They have a high bite force and can even bite through wire mesh. At the same time, however, they are extremely attractive birds that like to be kept in aviaries and for which high prices are paid. However, the aviaries must be made entirely of welded metal in order to take into account the gnawing tendency of this cockatoo.
In Australia, the Inca cockatoo is one of the most widely bred cockatoo species. This is due to the fact that it is completely protected in its homeland and wild-caught animals may only be kept with special permission from the nature conservation authorities. There have already been attempts to reintroduce these cockatoos to increase the population. The small number of young birds that grow up in human care is an indication that breeding is not easy. Breeding pairs can become very aggressive during the breeding season. The male Inca cockatoo that was breeding at the Perth Zoo repeatedly attacked the zookeeper, inflicting large bite wounds. Inca cockatoos are very rarely kept outside of Australia.
supporting documents
Individual evidence
- ↑ a b Forshaw, p. 181.
- ↑ a b Hoppe, p. 120.
- ↑ a b c Forshaw, p. 188.
- ↑ Hoppe, p. 125.
- ^ Forshaw, p. 182.
- ^ Forshaw, p. 183.
- ^ Forshaw, p. 184.
- ↑ a b c d e f Forshaw, p. 187.
- ^ Forshaw, p. 186 and p. 187.
- ↑ Hoppe, p. 123.
- ^ Forshaw, p. 189.
- ↑ a b Forshaw, p. 191.
- ↑ a b c Forshaw, p. 190.
- ^ Forshaw, p. 192.
- ↑ a b Hoppe, p. 126.
- ↑ Hoppe, p. 127.
- ^ Forshaw, p. 195.
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
- Cacatua leadbeateri in the endangered Red List species the IUCN 2008. Posted by: BirdLife International, 2004. Retrieved on January 25 of 2009.
- Videos, photos and sound recordings of Cacatua leadbeateri in the Internet Bird Collection