Cockatoos

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Cockatoos
Pink Cockatoo (Eolophus roseicapillus), female

Pink Cockatoo ( Eolophus roseicapillus ), female

Systematics
Sub-stem : Vertebrates (vertebrata)
Row : Land vertebrates (Tetrapoda)
Class : Birds (aves)
Order : Parrots (Psittaciformes)
Family : Cockatoos
Scientific name
Cacatuidae
GR Gray , 1840

The cockatoos (Cacatuidae) are a well-demarcated and easily recognizable family of birds in the order of the parrots (Psittaciformes). The most striking feature of the cockatoo is the feather bonnet , which is flat or bristled depending on the state of excitement. Over a very long bonnet for example, has palm cockatoo . In other species, such as the black cockatoo , it is significantly smaller. Cockatoos are on average larger than the other species that belong to the real parrots . The plumage of the cockatoo is generally less colorful than that of other parrots. Most cockatoos have a basic white, gray or black color. Like all parrots, the cockatoos have very powerful beaks. The beak morphology often shows adaptations to the preferred food.

Cockatoos are found in very different habitats. These include the tropical rainforests of the Pacific region as well as cultural areas of the temperate climatic zones in Victoria or Tasmania, Australia. Cockatoos mainly eat seeds, roots, fruits, flowers, flower buds and insects. In particular, the species that mainly find their food on the ground come together in swarms while foraging. In some species, several hundred birds can gather. Cockatoos are monogamous birds whose pairing does not end until one of the two birds dies. They nest in tree hollows. Some of the species are threatened by habitat destruction. The cause of a decline in the population can be the decline in suitable breeding trees.

The family comprises 6 genera and 21 species . The range of all cockatoo species is the Papua-Australian region.

Appearance

White-hooded cockatoo
Nasal cockatoo
( Cacatua tenuirostris )

Cockatoos are medium to large parrots with a length of 30–66 cm. Like all parrots, the cockatoos have a characteristic hooked bill that holds considerable strength. Large species with a massive beak are characterized by a posture that is almost vertical when at rest. The feet have 4 toes, the first and fourth toes pointing forward and the second and third pointing backwards. With these feet you can grab a lot and use them like a gripping hand.

The most noticeable distinguishing feature in comparison with other parrot families is the movable feather hood. Cockatoos usually jerk them up when worried or agitated. Only the New Caledonian Horned Parakeet is the only other parrot bird that also has a hood. However, these are only a few elongated crown feathers. Further characteristics are the possession of a gall bladder and a special feather structure, the powder down. The feathers of cockatoos are the only bird species to secrete a fine dust that cares for and protects the plumage. The plumage is colored white, gray, black or pink, with some species also with smaller yellow or red parts. The species of cockatiels (also: Kakadu parrot ) is one of today's cockatoos. Similarities are the feather bonnet, the powder down and the breeding behavior.

In a few species there is a pronounced sexual dimorphism . In many species, however, it is only weakly indicated or is even missing entirely.

distribution

Distribution area of ​​the cockatoos in Australia , New Guinea , Sunda Islands and the Philippines

Cockatoos have a much smaller range than other parrot families. They occur naturally only in Australasia . The northern limit of distribution runs at 19 ° North on the Philippine island of Luzon . The southern boundary of the range is Tasmania, where in addition to the helmet and the Galah and the Tasmanian yellow-tailed black cockatoo and the Gelbhaubenkakadu occur. Outside of Australia and New Guinea, the range of the individual cockatoo species does not overlap. No species occupies a habitat there that is also inhabited by another cockatoo species. In New Guinea, the palm , yellow-hooded and naked-eyed cockatoos each use their own ecological niche without being in competition with any other species of cockatoo. In Australia, on the other hand, cockatoos occasionally form cross-species swarms and are often competitors for nesting sites.

Three of the twenty-one species are found in both New Guinea and Australia. Eleven are restricted to the Australian continent. Some species, such as the pink cockatoo and cockatiel, can be found almost all over the Australian continent, while other Australian species have only very small ranges. This applies, for example, to Baudin's white-eared black cockatoo and Carnaby's white-eared black cockatoo . Seven other species of cockatoo are native to Indonesia , New Guinea , the Philippines and the Solomon Islands . The cockatoos that live outside Australia have a predominantly narrow distribution area: The Goffink's cockatoo, for example, only occurs on the Tanimbar Islands . The Moluccan cockatoo and the white-hooded cockatoo are limited in their distribution to the Moluccas . Cockatoos are absent from Borneo and many other Pacific islands, although fossils have been found in New Caledonia , for example .

Some cockatoo species have settled in areas outside of their natural range as refugees from captivity. Cockatoos are also found in New Zealand , Singapore , Hong Kong and Palau . Within Australia, two species have been introduced to regions where they are naturally absent. There are two feral populations of the yellow-crested cockatoo in the wheat belt of southwest Australia. Not only do they sometimes cause considerable damage to agriculture, they are also nesting site competitors to the endemic cockatoo species that occur there, which have a much lower population overall.

habitat

Red-tipped Cockatoo

Cockatoos use a wide range of different habitats in the tropics and subtropics. The most widespread species use open grasslands with sparse trees. This vegetation zone includes both moist savannas with a dry season lasting several months, dry savannas with deciduous dry forests and thorn-shrub steppes, which form the transition to the deserts and are therefore often referred to as semi-deserts. The open grassland species have benefited considerably, in part, from the development of the Australian continent by European settlers. Above all, the installation of cattle troughs allows them to settle in regions that previously had too few water points to be densely populated by them. The Inca cockatoo is an exception to this . This species of cockatoo is dependent on large, tree-lined areas and avoids flying over open, treeless landscapes. As a result, it has largely disappeared in the agriculturally developed regions of Australia.

Other species colonize tropical and subtropical rainforests, mangroves, gallery forests and even occur in alpine forests. They have also developed into urban habitats, and some species of cockatoo like the pink cockatoo and the yellow-crested cockatoo can be found in cities like Perth , Sydney , Melbourne and Canberra .

Diet and Lifestyle

The diet consists mainly of fruits and seeds . The nasal cockatoo ( Cacatua tenuirostris ) also eats roots and herbaceous plant parts. The black cockatoo also eats insect larvae and, thanks to its pointed beak, is able to pick insect larvae from hard and woody seeds. He also peeled trees to get wood-boring insects. In doing so, it can damage young trees in such a way that they buckle in strong winds.

Black Cockatoo , male

Outside of the breeding season, the cockatoos live gregariously, in small groups or in large schools with several hundred animals. However, this is not a social association, as it is known from mammalian herds, but a collection of individuals, couples and families, which is created through the same use of places to eat, drink and sleep. This creates very large swarms, often comprising more than 10,000 individuals. Cockatoos recognize the partner and their young in such groups. There is apparently no individual recognition of other conspecifics. Accordingly, cockatoo flocks have no ranking. In Australia, the cockatoos are considered to be large pests when they swarm into grain fields and plunder them.

behavior

Like most parrots, cockatoos, like humans, are more skilful with one of their feet, which also serves as a grasping organ, than with the other. Most cockatoos are left-footed. Cockatoos are monogamous birds in which a pair bond once established usually lasts until one of the partners dies. But at the same time they are extremely socially living birds that often appear in flocks. This is especially true outside of the breeding season. In particular, the species that find most of their food on the ground also form swarms during the breeding season. In the case of the Inca cockatoo, this goes so far that breeding pairs occasionally do not use the feeding grounds near the nesting hole, but fly several kilometers to join other Inca cockatoos. A number of cockatoo species have guard systems in which at least one cockatoo watches the surrounding area while the others feed on the ground. Such behavior can be found, for example, in Inca cockatoos and yellow-crested cockatoos. Pink cockatoos, on the other hand, do not have this guard system, but often join the flocks of yellow-crested cockatoos and also fly up when they call out for warning.

Some cockatoos are considered to be very playful, especially Galahs ( Eolophus roseicapillus ) and Korellas ( nose cockatoo ( Cacatua tenuirostris ) Nacktaugenkakadu ( Cacatua sanguinea )). It is reported of them that they do gymnastics on wire ropes, antennas and wind turbines, fly into dust devils in swarms, apparently for fun, or even slide backwards down playground slides. Therefore, in Australia the phrase "playing the galah" ( "galah" = "galah") is in terms of "the buffoon play" has become proverbial.

At least one cockatoo, the Palm Cockatoo ( Probosciger aterrimus ), even uses tools that it has made itself : it knocks with a Grevillea nut or a pruned branch prepared for it against the bark of dead tree trunks and in this way generates a sound that can be heard up to 100 m away. This is likely to notify your partner, but also any intruders who may be passing by, of your presence.

In the course of an experiment, the Goffink's cockatoo could be observed while teaching the use of tools to conspecifics. These then even improved the technology. According to the researchers, this is the first evidence of a social transmission of tool use in a bird .

voice

Most cockatoos have a very loud voice. They can make a wide variety of sounds, from croaking and screeching to whistling, and they can also mimic noises such as telephone rings or human voices. But they are not as talented in languages ​​as the African gray parrot, for example .

Reproduction

Pair of helmeted cockatoos , on the left the male

Cockatoos are cave breeders and are basically monogamous birds. The pair bond already begins in the flocks, which are made up of not yet sexually mature young birds. The cockatoos' courtship behavior is not very pronounced. They show a mock courtship in which the males usually strut towards the females in a tense posture and bow to them. Like the mutual care of plumage, this behavior mainly serves to intensify the cohesion of the couple.

Depending on the species, the breeding season lasts 18–30 days, the young birds are fed for 35–120 days. There are types, e.g. B. the black cockatoos ( Calyptorhynchus ), in which the males do not participate in the brood .

Predators and life expectancy

Only a few birds of prey hit adult cockatoos. The peregrine falcon beats parrots mostly up to the size of cockatiels. However, there are also indications that its prey range occasionally also includes pink and naked-eyed cockatoos. The Australian Hobby is to a height of 35 centimeters too small to be dangerous cockatoos. Even cockatiels are only exceptionally prey. Only the wedge-tailed harrier , crested kite , Sydney sparrow , rabbit eagle and the white-bellied sea eagle also beat larger cockatoos. Among the owls it is in particular the giant owl and the rusty owl that successfully hunt cockatoos. They usually attack birds sitting away from the flock.

Some mammals and reptiles are nest predators. However, cockatoos usually build their nests in eucalyptus trees . These are mainly characterized by smooth trunks, as the bark is shed. This makes it more difficult for nest robbers to get to the nest caves, some of which are very high. The pink cockatoo also removes the bark in the entrance area of ​​its nesting cavity, so that lizards, snakes and mammals cannot find a hold on the smooth trunks.

Like other parrots, cockatoos can get very old. A yellow- crested cockatoo ( Cacatua galerita ) lived to be 82 years old at London Zoo .

Cockatoos and people

Cockatoos as pets

Orange-hooded cockatoo , a subspecies of the yellow-cheeked cockatoo

Some species of cockatoo are popular pets . Like all other parrot species, cockatoos need a lot of attention. A species-appropriate keeping is therefore only possible with at least one partner bird of the same species. If the birds are not given ideal living conditions, psychological problems quickly arise in the animals, which are mainly expressed in constant screaming and plucking their feathers.

However, if you decide to buy such a pet, you have to be aware of certain problems. Due to the special feather structure and the formation of special powder downs, most cockatoos produce large amounts of dust, which settles in the entire room. In addition, most cockatoos have a pronounced need to gnaw, from which furniture is not immune. The voice of these parrots is also very loud, and they are very active especially at dusk. They need enough free flight every day in the apartment if they are kept in a room aviary, or a spacious outdoor aviary with a frost-protected and heated interior. Cage should be avoided because of the animals' great urge to move around.

It is also important to find out about the individual origins of the birds before buying. Wild caught are hardly for sale today, are problematic in the taming and are questionable in terms of species protection law. Hand-raised offspring of captive birds are tame from the start, but often poorly socialized, which can lead to sexual deficits, making the cockatoos useless for breeding. In addition, the birds tend to bond very closely to a certain caregiver, in the absence of which they can easily become problem animals. Obviously the best choice are young birds that have had contact with humans from the beginning but have grown up with conspecifics. These can be tamed without any problems, but are sufficiently socialized to be able to bond with a partner of the same species, which is the basis for species-appropriate parrot keeping.

Many cockatoos are susceptible to the psittacine beak and feather disease (PBFD; English for "feather and beak disease of parrots"). This is a highly contagious, incurable, and often fatal viral infection that occurs in parrot birds. It is the most common viral disease in parrots in Germany and now affects not only large parrots, but also budgies and other small parrot birds.

The causative agent of the PBFD is the Beak and Feather disease virus (BFDV) from the virus genus Circovirus . These are small, 12–21 nm large, non-enveloped DNA viruses . Circoviruses are very contagious. They have a high tenacity in the environment and are only safely killed by a few disinfectants (e.g. glutaraldehyde ). The infection is done by oral uptake of the virus or an airborne droplet infection. Due to the high tenacity, indirect transmission through inanimate vectors (cage furniture, clothing, claw scissors, etc.) is also possible. The incubation period , i.e. the period from infection to actual disease, can stretch on for months or even years. Therefore, when buying animals, there is a very high risk of the disease being introduced into a bird house.

Cockatoos as pests

Cockatoos can cause significant damage in agriculture. As a result, they are occasionally shot or poisoned. Other measures try to keep cockatoos away from agricultural areas by changing their habitat or to offer them targeted forage plants. In urban living spaces, they occasionally cause damage because they like to gnaw wood and also practice this on patio furniture, doors and window frames. Ornamental plants are also gnawed by them so that they die. Cockatoos also like to damage external cables and solar systems, television antennas and satellite dishes. A company in central Melbourne has suffered repeated financial damage after yellow-hooded cockatoos nibbled off the silicone seal on the shop windows. Black Cockatoos and Banks Black Cockatoos are known to gnaw the sheath of electrical cables in rural areas. They also like to destroy PVC-coated polyester fabrics such as those used in tents and canopies. Some species of cockatoo occasionally develop into particularly severe pests:

Yellow- crested cockatoos in the wild can become very tame; here on a balcony in Sydney, where they are regularly fed
  • Banks cockatoos are considered a pest on peanut plantations in Lakeland , a small agricultural region in the far north of Queensland . The cockatoos, which sometimes appear in flocks of several hundred birds, have learned to bite off the peanut plants just above the surface of the ground and pull the peanuts out of the ground. They also destroy the cables that supply irrigation systems.
  • Black cockatoos cause damage in young pine and Eucalyptus grandis plantations when they tear off the bark and wood in order to get to wood-boring insect and insect larvae.
  • The Carnaby's white-eared black cockatoo , a rare species of cockatoo endemic to southwest Australia, is considered a pest in pine plantations. Carnaby's white-eared black cockatoos regularly eat the main shoots of growing pine trees, which leads to malformations and greatly reduces the wood value of the trees. They also cause damage to nut and orchards and have learned to eat rapeseed.
  • The Baudin's white-eared black cockatoo , which is also native to southwest Australia, is an occasional pest in apple and pear orchards. They destroy the fruit to get to the kernels.

Subfamilies, genera, species, and subspecies

The approximately 20 cockatoo species are divided into three subfamilies:

Great White-crested Cockatoo
( Cacatua alba )
Cockatoo
( Callocephalon fimbriatum )
Black Cockatoo
( Calyptorhynchus funereus )
Pink Cockatoo
( Eolophus roseicapilla )
  • Subfamily Nymphicinae
    • Genus Nymphicus
  • Subfamily Calyptorhynchinae
    • Genus Black Cockatoos ( Calyptorhynchus )
      • Baudin's white-eared black cockatoo ( C. baudinii )
      • Banks Black Cockatoo ( C. banksii )
        • Banks Black Cockatoo ( C. banksii banksii )
        • Southern Banks Black Cockatoo ( C. banksii graptogyne )
        • Gould's red-tailed black cockatoo ( C. banksii macrorhynchus )
        • Western Australian Banks Black Cockatoo ( C. banksii naso )
        • Mathew's red-tailed black cockatoo ( C. banksii samueli )
      • Yellow-tailed Black Cockatoo ( C. funereus )
        • Black Cockatoo ( C. funereus funereus )
        • Tasmanian black cockatoo ( C. funereus xanthonotus )
      • Brown-headed Cockatoo ( C. lathami )
        • Queensland Brown -headed Cockatoo ( C. lathami erebus )
        • Kangaroo Island Brown -headed Cockatoo ( C. lathami halmaturinus )
        • Brown-headed Cockatoo ( C. lathami lathami )
      • Carnaby's white-eared black cockatoo ( C. latirostris )
  • Subfamily Cacatuinae
    • Tribe Microglossini
      • Genus Probosciger
        • Palm Cockatoo (Arakakadu) ( P. aterrimus )
          • Palm Cockatoo (Arakakadu) ( P. aterrimus aterrimus )
          • Great Palm Cockatoo ( P. aterrimus goliath )
          • Cape York Palm Cockatoo ( P. aterrimus macgillivrayi )
          • Van-Oort's Palm Cockatoo ( P. aterrimus stenolophus )
    • Tribe Cacatuini

swell

Single receipts

  1. ^ Forshaw, p. 51.
  2. ^ Ian Rowley: Family Cacatuidae (Cockatoos). In: Josep, del Hoyo; Andrew, Elliott; Jordi, Sargatal, Handbook of the Birds of the World. Volume 4: Sandgrouse to Cuckoos. Lynx Edicions, Barcelona 1997, ISBN 978-84-87334-22-1 , pp. 246-269.
  3. ↑ a b Hoppe, p. 14.
  4. ↑ a b Hoppe, p. 17.
  5. ^ David Steadman: Extinction and Biogeography in Tropical Pacific Birds . University of Chicago Press, Chicago 2006, ISBN 978-0-226-77142-7 , pp. 348 (English).
  6. ^ Andrew Styche: Distribution and Behavioral Ecology of the Sulfur-Crested Cockatoo (Cacatua Galerita L.) in New Zealand. In: Doctoral Thesis. Victoria University of Wellington, 2000, accessed March 27, 2010 .
  7. ↑ Hoppe, p. 15.
  8. ^ Forshaw, p. 186 and p. 188.
  9. ↑ a b c Ian Temby: Urban wildlife issues in Australia. 1999, In: Shaw et al. (Ed.): Proceedings Of The 4th International Symposium On Urban Wildlife Conservation. 2004 ( online ).
  10. ^ Forshaw, p. 75.
  11. ↑ Hoppe, p. 18.
  12. ^ Forshaw, p. 186 and p. 187.
  13. ↑ Cockatoos also watch each other . scinexx. Retrieved September 4, 2014
  14. ↑ AMI Auersperg, AMI von Bayern, S. Weber, A. Szabadvari, T. Bugnyar, A. Kacelnik: Social transmission of tool use and tool manufacture in Goffin cockatoos (Cacatua goffini). In: Proceedings of the Royal Society B: Biological Sciences. 281, 2014, doi: 10.1098 / rspb.2014.0972 , p. 20140972.
  15. ↑ Hoppe, p. 20.
  16. ↑ a b c Hoppe, p. 19.
  17. ^ Mary Bomford, Ron Sinclair: Australian research on bird pests: impact, management and future directions . In: Emu . tape 102 , no. 1 , 2002, p. 29-45 , doi : 10.1071 / MU01028 .
  18. ↑ a b Cameron, p. 155.
  19. ↑ Cameron, p. 156.
  20. ↑ Mike Ahmet: The damage caused by Red-tailed Black-Cockatoos (Calyptorhynchus banksii) on peanut and other crops within the farming district of Lakeland Downs, Cape York Peninsula. Report to the Queensland Department of Environment. 1998 ( PDF )
  21. ↑ Stephen Garnett: Red-tailed Black-Cockatoo damage and damage mitigation at Lakeland Downs, Cape York Peninsula. In: Eclectus. 5, 1998, pp. 26-34.
  22. ^ Susan House, Nadya Lees: Mammal browsing in hardwood plantations. Queensland Department of Primary Industries and Fisheries Note, 2005 Archive link ( Memento of the original from June 21, 2009 in the Internet Archive ) Info: The archive link has been inserted automatically and has not yet been checked. Please check the original and archive link according to the instructions and then remove this notice. @1@ 2Template: Webachiv / IABot / www2.dpi.qld.gov.au
  23. ↑ a b Denis Saunders: Conserving Carnaby's Black-Cockatoo: historical background on changing status. In: Cheryl Gole (ed.): Conserving Carnaby's black-cockatoo - future directions: proceedings from a conservation symposium, Perth, Western Australia, July 2, 2003. Birds Australia WA Inc: Perth, 2005, ISBN 0-9751429-0-9 , Pp. 9-18 ( PDF ( Memento of the original from November 8, 2009 on WebCite ) Info: The archive link was automatically inserted and not yet checked. Please check the original and archive link according to the instructions and then remove this note. ). @1@ 2Template: Webachiv / IABot / www.birdswa.com.au
  24. ^ Australian Government, Department of the Environment, Water, Heritage and the Arts : Species Profile and Threats Database: Calyptorhynchus latirostris . [1]
  25. ↑ Cameron, p. 22.
  26. ↑ David W. Winkler, Shawn M. Billerman, Irby J. Lovette: Bird Families of the World: A Guide to the Spectacular Diversity of Birds. Lynx Edicions (2015), ISBN 978-8494189203 . Page 261.

literature

Web links

Commons : Cockatoos (Cacatuidae)  - Collection of images, videos and audio files