A cockatoo is any of the 21 species of belonging to the family Cacatuidae, the only family in the superfamily Cacatuoidea. Along with the Psittacoidea () and the Strigopoidea (large New Zealand parrots), they make up the order Psittaciformes. The family has a mainly distribution, ranging from the Philippines and the eastern islands of Wallacea to New Guinea, the Solomon Islands and Australia.
Cockatoos are recognisable by their prominent crests and curved beak. Their plumage is generally less colourful than that of other parrots, being mainly white, grey, or black and often with coloured features in the crest, cheeks, or tail. On average, they are larger than other parrots; however, the cockatiel, the smallest cockatoo species, is medium-sized. Overview of Cockatiel Size, cockatielworld.co.uk The phylogenetic position of the cockatiel remains unresolved, except that it is one of the earliest offshoots of the cockatoo lineage. The remaining species are in two main clades. The five large black-coloured cockatoos of the genus Calyptorhynchus form one branch. The second and larger branch is formed by the genus Cacatua, comprising 12 species of white-plumaged cockatoos and three monotypic genera that branched off earlier, namely the pink and grey galah, the mainly grey gang-gang cockatoo and the large black-plumaged palm cockatoo.
Cockatoos prefer to eat seeds, , , fruit, flowers, and insects. They often feed in large flocks, particularly when ground-feeding. Cockatoos are monogamous and nest in . Some cockatoo species have been adversely affected by habitat loss, particularly from a shortage of suitable nesting hollows after large, mature trees are cleared; conversely, some species have adapted well to human changes and are considered agricultural pests.
Cockatoos are popular birds in aviculture, but their needs are difficult to meet. The cockatiel is the easiest cockatoo species to maintain and is by far the most frequently kept in captivity. White cockatoos are more commonly found in captivity than black cockatoos. Illegal trade in wild-caught birds contributes to the decline of some cockatoo species in the wild.
In Australian slang or vernacular speech, a person who is assigned to keep watch while others undertake clandestine or illegal activities, particularly gambling, may be referred to as a "cockatoo". Proprietors of small agricultural undertakings are often jocularly or slightly disparagingly referred to as "cocky farmers".
The relationships among various cockatoo genera are largely resolved, although the placement of the cockatiel ( Nymphicus hollandicus) at the base of the cockatoos remains uncertain. The cockatiel is alternatively placed basal to all other cockatoo species, as the sister taxon to the black cockatoo species of the genus Calyptorhynchus or as the sister taxon to a clade consisting of the white and pink cockatoo genera as well as the palm cockatoo. The remaining species are within two main clades, one consisting of the black species of the genus Calyptorhynchus while the other contains the remaining species. According to most authorities, the second clade includes the black palm cockatoo ( Probosciger), the grey and reddish galah ( Eolophus), and the gang-gang cockatoo ( Callocephalon), although Probosciger is sometimes placed basal to all other species. The remaining species are mainly white or slightly pinkish and all belong to the genus Cacatua. The genera Eolophus and Cacatua are Leucism. The genus Cacatua is further subdivided into the subgenus Licmetis, commonly known as corellas, and Cacatua, referred to as white cockatoos. Confusingly, the term "white cockatoo" has also been applied to the whole genus. The five cockatoo species of the genus Calyptorhynchus are commonly known as black cockatoos, and are divided into two subgenera— Calyptorhynchus and Zanda. The former group are sexually dichromatic, with the females having prominently barred plumage. The two are also distinguished by differences in the food-begging calls of juveniles.
The fossil record of cockatoos is even more limited than that of parrots in general, with only one truly ancient cockatoo fossil known: a species of Cacatua, most probably subgenus Licmetis, found in Early Miocene (16–23 million ago) deposits of Riversleigh, Australia. Although fragmentary, the remains are similar to the western corella and the galah. In Melanesia, subfossil bones of Cacatua species which apparently did not survive early human settlement have been found on New Caledonia and New Ireland. The bearing of these fossils on cockatoo evolution and phylogeny is fairly limited, although the Riversleigh fossil does allow tentative dating of the divergence of subfamilies.
Subfamily Nymphicinae
Subfamily Cacatuinae
Like other parrots, cockatoos have short legs, strong claws, a waddling gait and often use their strong bill as a third limb when climbing through branches. They generally have long broad wings used in rapid flight, with speeds up to being recorded for galahs.. The members of the genus Calyptorhynchus and larger white cockatoos, such as the sulphur-crested cockatoo and the pink cockatoo, have shorter, rounder wings and a more leisurely flight.
Cockatoos have a large bill, which is kept sharp by rasping the two jaws together when resting. The bill is complemented by a large muscular tongue which helps manipulate seeds inside the bill so that they can be de-husked before eating. During the de-husking, the lower jaw applies the pressure, the tongue holds the seed in place and the upper jaw acts as an anvil. The eye region of the skull is reinforced to support muscles which move the jaws sideways. The bills of male cockatoos are generally slightly larger than those of their female counterparts, but this size difference is quite marked in the palm cockatoo..
The plumage of the cockatoos is less brightly coloured than that of the other parrots, with species generally being either black, grey or white. Many species have smaller areas of colour on their plumage, often yellow, pink and red, usually on the crest or tail.. The galah and Major Mitchell's cockatoo are more broadly coloured in pink tones.. Several species have a brightly coloured bare area around the eye and face known as a periophthalmic ring; the large red patch of bare skin of the palm cockatoo is the most extensive and covers some of the face, while it is more restricted in some other species of white cockatoo, notably the corellas and blue-eyed cockatoo. The plumage of males and females is similar in most species. The plumage of the female cockatiel is duller than the male, but the most marked sexual dimorphism occurs in the gang-gang cockatoo and the two species of black cockatoos in the subgenus Calyptorhynchus, namely the red-tailed and glossy black cockatoos. The iris colour differs in a few species, being pink or red in the female galah and the pink cockatoo and red-brown in some other female white cockatoo species. The males all have dark brown irises.
Cockatoos maintain their plumage with frequent preening throughout the day. They remove dirt and oil and realign feather barbs by nibbling their feathers. They also preen other birds' feathers that are otherwise hard to get at. Cockatoos produce preen-oil from a uropygial gland on their lower back and apply it by wiping their plumage with their heads or already oiled feathers. Down feather is produced by specialised feathers in the lumbar region and distributed by the preening cockatoo all over the plumage..
Moulting is very slow and complex. Black cockatoos appear to replace their one at a time, their moult taking two years to complete. This process is much shorter in other species, such as the galah and long-billed corella, which each take around six months to replace all their flight feathers.
Three species occur in both New Guinea and Australia.. Some species have widespread distributions, with the galah, for example, occurring over most of Australia, whereas other species have tiny distributions, confined to a small part of the continent, such as the Baudin's black cockatoo of Western Australia or to a small island group, such as the Tanimbar corella, which is restricted to the Tanimbar Islands of Indonesia. Some cockatoos have been introduced accidentally to areas outside their natural range such as New Zealand, Singapore, and Palau, while two Australian corella species have been introduced to parts of the continent where they are not native.
Cockatoos occupy a wide range of habitats from forests in subalpine regions to mangroves. However, no species is found in all types of habitat.. The most widespread species, such as the galah and cockatiel, are open-country specialists that feed on grass seeds. They are often highly mobile fast flyers and are nomadic. Flocks of birds move across large areas of the inland, locating and feeding on seed and other food sources. Drought may force flocks from more arid areas to move further into farming areas.. Other cockatoo species, such as the glossy black cockatoo, inhabit woodlands, rainforests, shrublands and even alpine forests. The red-vented cockatoo inhabits mangroves and its absence from northern Luzon may be related to the lack of mangrove forests there.. Forest-dwelling cockatoos are generally sedentary, as the food supply is more stable and predictable.. Several species have adapted well to human modified habitats and are found in agricultural areas and even busy cities.
Some species require roosting sites that are located near drinking sites; other species travel great distances between the roosting and feeding sites. Cockatoos have several characteristic methods of bathing; they may hang upside down or fly about in the rain or flutter in wet leaves in the canopy. Cockatoos have a preferred "footedness" analogous to human handedness. Most species are left-footed with 87–100% of individuals using their left feet to eat, but a few species favor their right foot.
Like most parrots, the cockatoos are cavity bird nest, nesting in holes in trees, which they are unable to excavate themselves. These hollows are formed from decay or destruction of wood by branches breaking off, fungi or insects such as termites or even where their ranges overlap. In many places these holes are scarce and the source of competition, both with other members of the same species and with other species and types of animal. In general, cockatoos choose hollows only a little larger than themselves, hence different-sized species nest in holes of corresponding (and different) sizes. If given the opportunity, cockatoos prefer nesting over above the ground and close to water and food..
The nesting hollows are lined with sticks, wood chips and branches with leaves. The eggs of cockatoos are oval and initially white, as their location makes camouflage unnecessary.. However, they do become discoloured over the course of incubation. They range in size from in the palm and red-tailed black cockatoos, to in the cockatiel. Clutch size varies within the family, with the palm cockatoo and some other larger cockatoos laying only a single egg and the smaller species laying anywhere between two and eight eggs. Food supply also plays a role in clutch size. Some species can lay a second clutch if the first fails. Around 20% of eggs laid are infertile.. The cockatoos' incubation and brooding responsibilities may either be undertaken by the female alone in the case of the black cockatoos or shared amongst the sexes as happens in the other species. In the case of the black cockatoos, the female is provisioned by the male several times a day. The young of all species are born covered in yellowish down, bar the palm cockatoo, whose young are born naked.. Cockatoo incubation times are dependent on species size, with the smaller cockatiels having a period of around 20 days and the larger Carnaby's black cockatoo incubating its eggs for up to 29 days.
The nestling period also varies by species size, with larger species having longer nestling periods. It is also affected by season and environmental factors and by competition with siblings in species with clutch sizes greater than one. Much of what is known about the nestling period of some species is dependent on aviary studies – aviary cockatiels can fledge after 5 weeks and the large palm cockatoos after 11 weeks. During this period, the young become covered in juvenile plumage while remaining in the hollow. Wings and tail feathers are slow to grow initially but more rapid as the primary feathers appear. Nestlings quickly reach about 80–90% of adult weight about two-thirds of the time through this period, plateauing before they leave the hollow; they fledge at this weight with wing and tail feathers still to grow a little before reaching adult dimensions.. Growth rate of the young, as well as numbers fledged, are adversely impacted by reduced food supply and poor weather conditions..
Many species forage for food in the canopy of trees, taking advantage of serotiny (the storage of a large supply of seed in cones or gumnuts by plant genera such as Eucalyptus, Banksia and Hakea), a natural feature of the Australian landscape in dryer regions. These woody fruiting bodies are inaccessible to many species and harvested in the main by parrots, cockatoos and rodents in more tropical regions. The larger cones can be opened by the large bills of cockatoos but are too strong for smaller animals.. Many nuts and fruits lie on the end of small branches which are unable to support the weight of the foraging cockatoo, which instead bends the branch towards itself and holds it with its foot..
While some cockatoos are generalists taking a wide range of foods, others are specialists. The glossy black cockatoo specialises in the cones of trees of the genus Allocasuarina, preferring a single species, A. verticillata. It holds the cones in its foot and shreds them with its powerful bill before removing the seeds with its tongue. Some species take large numbers of insects, particularly when breeding; in fact the bulk of the yellow-tailed black cockatoo's diet is made up of insects. The large bill is used in order to extract grubs and larvae from rotting wood. The amount of time cockatoos have to spend foraging varies with the season. During times of plenty they may need to feed for only a few hours in the day, in the morning and evening, then spend the rest of the day roosting or preening in trees, but during the winter most of the day may be spent foraging. The birds have increased nutritional requirements during the breeding season, so they spend more time foraging for food during this time. Cockatoos have large crops, which allow them to store and digest food for some time after retiring to a tree..
Like other parrots, cockatoos can be afflicted by psittacine beak and feather disease (PBFD). The viral infection causes feather loss and beak malformation and reduces the bird's overall immunity. Particularly prevalent in sulphur-crested cockatoos, little corellas and galahs, it has been recorded in 14 species of cockatoo to date. Although unlikely to significantly impact on large, healthy populations of birds in the wild, PBFD may pose a high risk to smaller stressed populations.
A white cockatoo and a sulphur-crested cockatoo were found to be infected with the protozoon Haemoproteus and another sulphur-crested cockatoo had the malaria parasite Plasmodium on analysis of faecal samples at Almuñecar ornithological garden in Granada in Spain. Like amazon parrots and macaws, cockatoos frequently develop cloacal . The relationship with malignancy is unknown, as is the cause, although a parrot Papillomaviridae has been isolated from a grey parrot with the condition.
Several rare species and subspecies, too, have been recorded as causing problems. The Carnaby's black cockatoo, a threatened Western Australian endemism, has been considered a pest in pine plantations where the birds chew off the leading shoots of growing pine trees, resulting in bent trunks and reduced timber value. They are also known to damage nut and fruit crops, and have learnt to exploit canola crops. The Baudin's black cockatoo, also endemic to the south-west of Western Australia, can be a pest in apple and pear where it destroys the fruit to extract the seeds. Muir's corella, the nominate subspecies of the western corella, is also a declared pest of agriculture in Western Australia, as well as being nationally vulnerable and listed under state legislation as being "rare or likely to become extinct".
The principal threats to cockatoos are habitat loss and the wildlife trade. All cockatoos are dependent on trees for nesting and are vulnerable to their loss; in addition many species have specialised habitat requirements or live on small islands and have naturally small ranges, making them vulnerable to the loss of these habitats. Cockatoos are popular as pets and the capture and trade has threatened some species; between 1983 and 1990, 66,654 recorded salmon-crested cockatoos were exported from Indonesia, a figure that does not include the number of birds caught for the domestic trade or that were exported illegally. The capture of many species has subsequently been banned but the trade continues illegally. Birds are put in crates or bamboo tubing and conveyed on boats out of Indonesia and the Philippines.. Not only are the rare species smuggled out of Indonesia but also common and rare cockatoos alike are smuggled out of Australia; birds are sedated, covered in nylon stockings and packed into PVC tubing which is then placed in unaccompanied luggage on international flights. Mortality is significant (30%) and eggs, more easily hidden on the bodies of smugglers on flights, are increasingly smuggled instead. Trafficking is thought to be run by organised gangs, who also trade Australian species for overseas species such as macaws coming the other way..
All species of cockatoo except the cockatiel are protected by the Convention on International Trade in Endangered Species of Wild Fauna and Flora (CITES), which restricts import and export of wild-caught parrots to special licensed purposes. Five cockatoo species (including all subspecies)—the Tanimbar corella ( Cacatua goffiniana), red-vented cockatoo ( Cacatua haematuropygia), Moluccan cockatoo ( Cacatua moluccensis), yellow-crested cockatoo ( Cacatua sulphurea) and palm cockatoo ( Probosciger aterrimus)—are protected on the CITES Appendix I list. With the exception of the cockatiel, all remaining cockatoo species are protected on the CITES Appendix II list.CITES (27 April 2011). Appendices I, II and III. Accessed 8 September 2011
The cockatiel is by far the cockatoo species most frequently kept in captivity. Among U.S. bird keepers that participated in a survey by APPMA in 2003/04, 39% had cockatiels, as opposed to only 3% that had (other) cockatoo species.Wool-N-Wings (2006). Bird Ownership Statistics in USA. Retrieved 10 September 2011. The white cockatoos are more often encountered in aviculture than the black cockatoos. Black cockatoos are rarely seen in European zoos due to export restrictions on Australian wildlife but birds seized by governments have been loaned.
Cockatoos are often very affectionate with their owner and at times other people but can demand a great deal of attention. It has been suggested that cockatoos' need for physical attention from humans may stem from suboptimal rearing techniques – young birds being removed from parental care for hand-rearing too early in the belief that this will produce a more suitable pet, leading the bird to seek out physical contact from humans as a parent substitute. Furthermore, their intense curiosity means they must be given a steady supply of objects to tinker with, chew, dismantle and destroy. Parrots in captivity may suffer from boredom, which can lead to stereotypy, such as feather-plucking. Feather plucking is likely to stem from psychological rather than physical causes. Other major drawbacks include their painful bites,. and their piercing screeches.. The salmon-crested and white cockatoo species are particular offenders.. All cockatoos have a fine Down feather on their feathers, which may induce allergy in certain people. In general, the smaller cockatoo species such as Goffin's and quieter Galah's cockatoos are much easier to keep as pets. The cockatiel is one of the most popular and easiest parrots to keep as a pet, and many colour mutations are available in aviculture.
Larger cockatoos can live 30 to 70 years depending on the species, or occasionally longer, and cockatiels can live for about 20 years. As pets they require a long-term commitment from their owners. Their longevity is considered a positive trait as it reduces instances of the loss of a pet. The oldest cockatoo in captivity was a pink cockatoo named Cookie, residing at Brookfield Zoo in Chicago, which lived to be 83 years old (1933–2016). A salmon-crested cockatoo named King Tut who resided at the San Diego Zoo was nearly 69 when he died in 1990 and a palm cockatoo reached 56 in London Zoo in 2000. However, anecdotal reports describe birds of much greater ages. Cocky Bennett of Tom Ugly's Point in Sydney was a celebrated sulphur-crested cockatoo who was reported to have reached an age of 100 years or more. He had lost his feathers and was naked for much of his life. A palm cockatoo was reported to have reached 80 or 90 years of age in an Australian zoo, and a little corella that was removed from a nest in central Australia in 1904 was reported still alive in the late 1970s. In February 2010, a white cockatoo named Arthur was claimed to be 90 years old; he had lived with a family for generations in Dalaguete, Cebu, before being taken to Cebu City Zoo.
Trained cockatoos are sometimes seen in bird shows in zoos. They are generally less motivated by food than other birds; some may respond more to petting or praise than food. Cockatoos can often be taught to wear a parrot harness, enabling their owners to take them outdoors. Cockatoos have been used in animal-assisted therapy, generally in nursing homes.
Cockatoos often have pronounced responses to musical sounds and numerous videos exist showing the birds dancing to popular music. Research conducted in 2008 with an Eleonora cockatoo named Snowball had indicated that this particular individual is indeed capable of beat induction—perceiving human-created music and synchronizing his body movements to the beat.
The government of the Australian Capital Territory adopted the gang-gang cockatoo as its official faunal emblem on 27 February 1997. The short-lived budget airline Impulse Airlines featured a sulphur-crested cockatoo on its corporate livery (and aeroplanes). The palm cockatoo, which has a unique beak and face colouration, is used as a symbol by the World Parrot Trust.
Two 1970s police dramas featured protagonists with pet cockatoos. In the 1973 film Serpico, Al Pacino's character had a pet white cockatoo and the television show Baretta saw Robert Blake's character with Fred the Triton cockatoo. The popularity of the latter show saw a corresponding rise in popularity of cockatoos as pets in the late 1970s. Cockatoos have been used frequently in advertising; a cockatoo appeared in a 'cheeky' (and later toned-down) 2008 advertising campaign for Cockatoo Ridge Wineries.
Genera and species
Subfamily Calyptorhynchinae: Black cockatoos
Morphology
Voice
Distribution and habitat
Behaviour
Breeding
Diet and feeding
Predators and threats
Social learning
Relationship with humans
Pests
Status and conservation
Aviculture
Culture
Intelligence
Notes
Cited texts
External links
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