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Sulphur-crested Cockatoo FAMILY: Cacatuidae GENUS: Cacatua SPECIES: galerita
Description: Immature birds resemble adults but are extremely difficult to sex. Length:450-500mm. Distribution: Across northern and eastern Australia. Habitat: Forests and woodlands including wet sclerophyll and rainforest. Diet: Seeds, grains, nuts, fruits, bulbs, fruits, insects and insect larvae. Breeding: May-September in the north, August-January in the south. Usual nesting site is a large hollow limb or a hollow tree trunk most often at least 10m above ground. It appears that tall eucalypts close to or bordering water courses are preferred nesting sites. Both males and females prepare the nest by chewing around the entrance and inside the hollow which may be excavated to some depth. The nest base is rotten wood. In captivity hollow eucalypt logs are best suited for breeding. The log should be approximately 35-40 cm in internal diameter and about 1m in length. The log should be suspended vertically or in an inclined position. Some birds prefer entrances at the front of the log, whereas others prefer an entrance on top. The preferred nesting material is a mixture of wood shavings and dirt or peat moss. Courtship Display Male Sulphur-crested Cockatoos strut towards females with the crest erect and tail feather spread wide. He also nods/bobs and flicks the head from side to side whilst emitting a low chuckling call. These displays are often performed during the process of nest preparation and many such displays usually precede the actual copulation. Sexual Maturity These birds usually breed at 4-5 years of age. However, this may not always be the case. There are records of Sulphur-crested Cockatoos breeding at 2 years of age but this is under rather unusual circumstances such as in an overabundance of food. Similarly, sexually mature pairs may not breed until 6 or 7 years of age, depending on prevailing circumstances. Clutch: 1-3 white oval eggs. Incubation period: 30days. Fledging usually occurs at 9 to 12 weeks. Chicks remain with the parents for an indefinite period thereafter however. Mutations and Hybrids: Lutino Sulphur-crests are similar to the normal variety but with a pale beak and flesh coloured feet and eyes. Hybrids have been recorded with Major Mitchell, Galah, Little (short-billed) and Slender- (long) billed Corellas Suitable Aviaries and Compatible Birds Historically, this species has been kept as a pet bird and most of us are probably aware of the typical "cocky-cage". As a minimum, a single bird may be housed in such a cage provided it measures at least 800mm x 600mm x 1200mm (approximately). Pairs can be kept in a slightly larger cage. However, these birds always fare better (and look more spectacular) in larger aviaries. These should be somewhere in the vicinity of 2m wide x 2m high x 5 or 6m long so as to provide amply flight space and to accommodate nesting logs etc. The wire should be of a heavy duty grade, as cockatoos easily chew holes in lighter grade wire. Similarly, the frame should be constructed of steel to avoid the birds chewing the structure away. Species Specific Problems Intestinal worms are a common problem in species which spend considerable time on the ground. Similarly, fungal infections may become a problem. These are relatively easily dealt with however simply by maintaining a high standard of hygiene. Another problem encountered in this species is Psittacine beak and feather disease. This is an incurable disease which is transmitted through feaces. Essentially, it results in poor feather growth and feathers which don't replace themselves when they fall out. Similarly, the beak is also affected and becomes fragile and does not repair itself. The bills of birds with this condition have a deep black, glossy appearance rather than the normal chalky grey colour. It is advisable to test birds suspected to have this condition. The best course of action for affected birds is to destroy them as there is no cure. Infected birds will infect their offspring simply by feeding them as there is always chances of contact with faeces in the nest and during feeding of the young. Feather plucking is also common to Sulphur-crested Cockatoos. This has a range of causes and can usually be rectified (see our articles in the "Regular Features" section of our website). |