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 Feeding Parrots from Parrots - An essential reference for keeping more than 200 parrot family species by David Alderton Photography by Cyril Laubscher Sponsored by:  There are five different genera of cockatoos, but it is the members of the Cacatua genus that are most commonly represented in collections; the various black cockatoos are all scarce in aviculture. The feature that distinguishes this group of birds is the crest on their heads, which is usually raised when they are excited or alarmed. The shape and length of this crest varies; in the case of the Goffin's Cockatoo, the crest is relatively short, whereas the feathers are long and broad in the Umbrella Cockatoo. Compatibility is very important when selecting breeding stock; try to start with proven pairs. Umbrella Cockatoo Distribution: Central and northern Moluccan islands, Indonesia. Size: 46cm (18in). Sexing: Cocks usually have darker, blackish irises, whereas those of hens are reddish brown in colour. Youngsters: Resemble adults in appearance, except that their irises are dark grey in colour. Although they lack the bright colours of some species, these large white cockatoos are very handsome birds, which take their common name from the umbrella-like shape formed by the broad feathers of their crest. Unfortunately, Umbrella Cockatoos have a reputation for being extremely destructive, and can also be very noisy birds. As with other Cacatua species, the typical clutch is two eggs, and the incubation period lasts about 28 days. The chicks fledge when they are about 12 weeks old. If you have to remove chicks from the nest for hand-rearing, you may find that they are starting to talk by the time they are independent. Hand-raised youngsters will develop into great companions, but if you buy adult birds, they are likely to be nervous, and you should keep them only in aviary surroundings. Greater Sulphur-crested CockatooCacatua galerita
These cockatoos are best known in Australian collections, although two of the three island races are kept and bred elsewhere in the world. These are the Triton (C. g. triton), distinguishable by its blue rather than whitish skin coloration around the eyes and its broader, more rounded crest feathers, and the so-called Medium Sulphur-crested (C. g. eleonora). This latter race, found in the Aru Islands, is similar to the Triton, but is distinguishable by its smaller size. The skin of the eye-ring is whitish, except in young birds, where it has a bluish tinge. In.all three races, incubation takes about 30 days, with the chicks emerging from the nest for the first time from 12 weeks old onwards. Goffin's Cockatoo Distribution: The Tenimbar Islands of Indonesia. Introduced to Tual in the Kai Islands by native people of the area. Rare in aviculture until the 1970s, these delightful cockatoos are now threatened by deforestation in their homelands. Goffin's Cockatoos are destructive birds, in spite of their relatively small size, and must be housed in robust surroundings. Unfortunately, pairs tend to be more reluctant to nest than other species. Adult pairs can prove very shy and it may be that they require more privacy; site the nestbox in a quiet, shaded part of the aviary. Two or three eggs form the typical clutch and these should hatch after an incubation period of 28 days. Provide a variety of rearing foods, such as chickweed, corn-on-the-cob and perpetual spinach, for this and other species. Try to monitor the progress of the chicks without disturbing their parents, in case they start to neglect one or both of their offspring. Chicks should leave the nest at about 11 weeks old. Philippine Red-vented Cockatoo Distribution: The Philippine Islands. The Philippine Red-vented Cockatoo is another species that has become better known in aviculture since the early 1980s and is now being bred in various collections. The hen normally lays two eggs, which hatch after about 24 days. The chicks will emerge from the nestbox when they are just over ten weeks old. These cockatoos have proved rather difficult to establish in the past. They were often afflicted with heavy tapeworm infestations, which needed treatment, and aspergiliosis. The latter was probably contracted from the nest litter- studies of breeding sites in the wild have revealed heavy contamination with the spores of this fungus - and usually proves fatal. Imported stock was also rather vulnerable to candidiasis, caused in part by a lack of dietary Vitamin A. Recent studies from the Philippines suggest that deforestation has had a serious impact on the number of these cockatoos, and their export is now prohibited. Although never traded in large numbers, a small established breeding population should now ensure that home-bred chicks remain available. Leadbeater's Cockatoo
These striking birds, also known as Major Mitchell's Cockatoos, are sadly not widely available, and surplus stock inevitably commands a very high price. Coloration is variable, with the lower parts up to the breast being white rather than pale pink in some individuals. One of the problems in establishing this species has been that cocks tend to be aggressive and will often attack, and even kill, the hens. There is consequently a shortage of hens in collections. When they do nest, the hens will spend several weeks gnawing the woodwork of the nestbox before laying up to four eggs. The young hatch about 28 days later, and the chicks emerge from the box two months old. Leadbeater's Cockatoos have a long reproductive life; a pair obtained in 1903 successfully reared a check 37 years later! Introduce young birds to each other to help ensure compatibility. Moluccan Cockatoo Distribution: Southern Moluccan islands of Indonesia. Highly variable in coloration, Moluccan or Rose-crested Cockatoos can range from shades of pink to almost white. Brighter coloured birds are believed to produce similarly coloured offspring. These cockatoos resemble the Umbrella Cockatoo, but are somewhat larger in size and have a rose-coloured crest. Hand-raised chicks may develop into marvellous pets, forming a strong bond with their owners and proving very responsive. But, like other cockatoos, they can be very demanding, and their loud calls and destructive natures can create problems in the home. When breeding, hens lay two eggs, which should hatch after a period of about 28 days. The chicks develop slowly, only leaving the nest for the first time when they are about 15 weeks old. Hand-raising Moluccan chicks is therefore a lengthy process compared with hand-rearing other species. Blue-eyed Cockatoo Distribution: Islands of New Britain and New Ireland in the Bismarck Archipelago. Closely related to the Greater Sulphurcrested Cockatoo, this species has darker blue skin around the eyes, and a much broader crest than the Triton race (C. g. triton). The Blue-eyed is relatively uncommon in aviculture, and you are more likely to see it in zoos and bird gardens than in private collections. Like other cockatoos, these birds are quite hardy once acclimatized, but you should not transfer recently imported stock outside during the colder months of the year, even if the birds were captive bred. Breeding details are similar to those of the Greater Sulphur-crested Cockatoo (see page 175). Bare-eyed Cockatoo Distribution: North and central- eastern parts of Australia, with a separate population also present in southern New Guinea. Although not widely kept outside Australia, these cockatoos, also called Little Corellas, are occasionally bred in captivity. Potentially, they are quite prolific; a pair kept at San Diego Zoo had 103 chicks between 1929 and 1970, the young birds being reared by hand. Bare-eyed Cockatoos are quite pugnacious, however, especially when they are breeding, and a tame bird that has no fear of people may not hesitate to turn on its owner when he or she enters the aviary. The usual clutch is comprised of three or four eggs, and incubation lasts 27 days. The chicks normally leave the nesting site at about nine weeks old and are then fed mainly by the cock for a short period. Lesser Sulphur-crested Distribution: Sulawesi (formerly Celebes) and neighbouring islands. One of the best-known cockatoos in aviculture, and widely kept as a pet, the Lesser Sulphur-crested occurs in several forms through its range. The most distinctive subspecies is the Citron-crested (C. s. citrinocristata), which has an orange rather than yellow crest and ear coverts, and occurs on the island of Sumba. It is well represented in aviculture but, as with other cockatoos, compatibility can be a problem. The Timor race (C. s. parvula) is the smallest, at just 30cm (12in) long. Lesser Sulphur-crested Cockatoos can be extremely nervous when first acquired, and you should only obtain genuine youngsters as pets. Two eggs form the usual clutch, and these hatch after a period of 27 days. The young cockatoos emerge from the nestbox around ten weeks later, but it will take much longer - up to eight weeks - for their beaks and feet to darken to the black coloration of those of adults. Long-billed Corella Distribution: South-eastern and southwestern parts of Australia. Their greatly lengthened upper mandible, which is used for digging in the ground, gives these cockatoos an unmistakable appearance. In their native Australia they are often considered a pest by farmers, as they will excavate newly sown grain. Also known as the Slender-billed Cockatoo, this species is very rare in aviculture collections outside Australia, and is likely to remain so, as the export of such native species is forbidden, except to zoos or scientific collections. There are probably only a dozen or so in the whole of the United States, and even fewer in Europe, although the species has bred in captivity at the extensive Loro Parque collection of parrots on the island of Tenerife, so you are unlikely to encounter this distinctive cockatoo. Gang-gang Cockatoo Distribution: South-eastern Australia. Size: 35cm (13-3/4 in). Sexing: Cocks are easily recognizable by their bright red heads and crests, whereas those of hens are greyish. Youngsters: Resemble hens, but young cocks can be recognized by the red tipping on the crest feathers, and sporadic red plumage on the head. Gang-gang Cockatoos are rarely kept, even in their Australian homeland. They are particularly prone to featherplucking, which appears to arise through boredom. Provide plenty of branches for them to gnaw, and give them plenty of small seeds, such as millet, as part of their regular diet, to keep them occupied. Fir cones have also been used to provide then with a source of interest as they seek to extract the nuts. In spite of this problem, a number of successful breeding results have been recorded. Incubation of the two eggs lasts about 25 days, and the chicks may fledge as soon as six weeks later. Palm Cockatoo
This is the largest species of cockatoo, and unmistakable in appearance. The distinctive bare reddish cheek patches are an indicator of the bird's state of health, becoming pale when the cockatoo is sick and turning redder during periods of excitement, presumably because of alterations to the blood flow to the skin. Palm Cockatoos are not common avicultural subjects and since 1987 they have been totally protected under the international CITES agreement, for fears that they are declining in the wild. Vendors therefore now need a permit from their CITES management authority, even for captive-bred youngsters. Breeding of the species has been problematic in the past, but now pairs are nesting more frequently in various collections worldwide. The incubation period may last up to 35 days, with the single egg being laid on a bed of sticks, up to 15cm (6in) deep, which the adult birds carry to the nestbox. It takes two weeks for the chick to gain any feathers, and as long as 14 weeks before it fledges. Raw onion is favoured by some pairs, but it may be best to withhold this when they have a chick. Black Cockatoo Distribution: South-eastern and southwestern Australia. There are two distinct races of this cockatoo, of which the Yellow-tailed is the most colourful. The other is the White-tailed Black Cockatoo (C. f. baudinii), also known as Baudin's Cockatoo, which is found in a small area of southwestern Australia. The Yellowtailed race occurs in the southeastern part of the country. Very few of these cockatoos, of either race, are currently kept in collectors, either in their homeland or elsewhere in the world. Their export has been prohibited for many years. Black Cockatoos are said to be very fond of greenstuff, and also regularly eat insects, such as mealworms. Their loud, penetrating calls are audible at a distance of one kilometre away. Despite their rarity in aviculture, they appear to breed without undue difficulty. Incubation is thought to last about 28 days and the chicks will normally fledge when they are about ten weeks old. Glossy Black Cockatoo Distribution: Eastern Australia and on Kangaroo Island. There appear to be no records of these cockatoos being kept outside Australia. In the wild, they are usually found close to Casuarina trees, which provide the nuts on which they feed. In captivity, they will take sunflower seed instead, and could probably be induced to eat pine nuts as well. Several Australian breeders are now being successful with this species. Hens may start breeding when only two years old; relatively young for cockatoos. The incubation period is quite long - usually lasting between 29 and 32 days - and the chicks will then remain in the nest for at least eight weeks before fledging. Red-tailed Black Cockatoo Distribution: Parts of north, eastern and western Australia, with a small isolated population in western Victoria and neighbouring south-eastern South Australia. Again, stock of this species, also known as the Banksian Cockatoo, is very rare outside Australia. Cock birds are said to become very tame if they have been hand-raised, whereas hens lose their tameness soon after becoming independent. ln the wild, these cockatoos rely less on insects in their diet than other related black species, feeding largely on nuts and seeds. Red-tailed Black Cockatoos have a long reproductive life - a cock bird known to be at least 36 years old has bred successfully at Adelaide Zoo in Australia. In the wild, nests are generally found in eucalypt trees, and the hen usually lays only one egg, which hatches after a period of 30 days. (If two eggs are laid and hatch, the youngest chick is usually neglected and will die unless it is removed for hand-rearing.) The young chick will fledge at the age of about 12 weeks, but it wili be a further three or four months before it is totally independent of its parents. Galah Cockatoo Distribution: Throughout much of Australia, except for some coastal areas, notably the eastern and south-western sea boards. Also known as the Roseate Cockatoo, this species is quite widely kept outside its Australian homeland, although pairs are expensive. In the wild, it is often considered to be a pest, and large numbers are destroyed annually. Pressure is being put on the Australian government to allow controlled export of some of these cockatoos to aviculturists overseas, rather than annihilating whole flocks of them. Although placed in a separate genus, the Galah is quite closely related to the Cacatua species. Hybrids have been produced on various occasions, although this practice is not to be encouraged. Galahs have a number of virtues as aviary birds; they are considerably less noisy than the Cacatua species and often more prolific, laying up to five eggs in a clutch, and sometimes nesting twice during the course of a breeding season. Some pairs show a stronger nestbuilding instinct than others, filling their nestbox with items such as bark and millet sprays collected around the aviary. Development of the chicks, which hatch after a period of about 25 days, is rapid, and they leave the nest when just seven weeks old. Ensure that they receive a balanced diet to minimize the risk of them developing fatty tumours, called lipomas. There is no effective treatment for these, apart from surgery to remove them, and they may recur. Photographic ReferencesPhoto 1: Greater Sulphur-crested Cockatoo These lively cockatoos are popular in Australia as pets and aviary birds, but are not common at present in Europe or North America. Photo 2: Leadbeater's Cockato This beautiful cockatoo is unfortunately rarely seen in collections. The depth of pink coloration varies - some birds are very pale, almost whitish in parts. Photo 3: Palm Cockatoo Although their powerful beaks can prove very destructive, tame Palm Cockatoos are very gentle and their whistlelike call is relatively quiet. |
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Distribution: New Guinea and neighbouring islands, as well as eastern Australia. Introduced to New Zealand during the 1920s.
Distribution: The eastern interior of Australia.
Distribution: Aru Islands, plus New Guinea and the Cape York Peninsula of northern Australia. 
