Introduction
Sulphur-crested cockatoos (Cacatua galerita) can damage crops in the south-west of Western Australia and compete with native cockatoo species. The sulphur-crested cockatoo is native to northern and eastern Australia but introduced populations are present in the south-west of Western Australia, where their numbers are reduced whenever possible.
Identification
Sulphur-crested cockatoos are white birds with a long crest that is sulphur-yellow and forward-curving. Adult birds are between 44 to 49 cm, making them slightly larger than the white corellas and pink and grey galahs that may also be seen in the south-west of Western Australia.
Sulphur-crested cockatoos have pale yellow ear coverts and washed-yellow underwings and tails, which are clearly visible when the birds are in flight. The rings of naked skin around the eyes are whitish-blue and the large bills and legs are black.
Male and female birds are similar in appearance, although females are slightly smaller and have dark reddish brown eyes, as opposed to the dark brown eyes of male birds. Immature birds are similar in appearance to adults but very young birds have tinges of grey on the crown, back and wings and have paler eyes than adults.
Behaviour
The distinctive flight action of the sulphur-crested cockatoo is characterised by an uneven wing beat (flap, flap, glide) on stiff, broad and rounded wings.
The birds are noisy and conspicuous, with loud and raucous screeching calls and are found in pairs or family parties during the breeding season. Flocks of up to 100 birds have been reported in the south-west of Western Australia. When a flock is feeding on the ground, a few sentinel birds keep watch from nearby trees, rising into the air and screeching loudly at the approach of danger. The birds sometimes associate with little corellas in mixed flocks.
The species does not migrate, though some local seasonal movements have been noted. Banding records show that one tagged bird covered a distance of 30km before being caught again 4 years later.
Food and habitat
Sulphur-crested cockatoos range over forest, woodland, savannah and cultivated areas, but prefer to roost along watercourses. They feed in open areas on grain, seeds, nuts, berries, flowers, nectar, leaf-buds, insects and their larvae, and rhizomes. They are attracted to seeding Marri trees and wild melons.
Their roosts near watercourse may be several kilometres from their food supplies, they return to these areas for both resting and nesting.
Breeding and lifespan
The time of breeding season is variable, occurring between August and January in the south-east and May and August in the north-west. It is thought that the birds breed between July and October in the south-west of Western Australia.
Two or three white eggs are laid on a bed of wood dust, usually in a hollow limb or a hole in a eucalypt tree, often near or in water. Nests are also found in cliffs and haystacks. Both sexes brood the eggs during the 30 day incubation period, and the young leave the nest after 6 to 10 weeks to join post-breeding flocks.
Sulphur-crested cockatoos can live to 100 years in captivity. It is likely that birds in the wild could live for several decades.
Distribution
The sulphur-crested cockatoo is a native of eastern and northern Australia. Its range extends from the Kimberley region in Western Australia, east to Cape York and south to Tasmania. The species also occurs in New Guinea and its offshore islands, and on the Aru islands.
It is introduced to New Zealand and was introduced to the south-west region of Western Australia as a result of accidental and deliberate release of pet birds, it was recorded present there before 1935. The sulphur-crested cockatoo is now found in an area from Waroona north to Bullsbrook and Muchea. It has also been recorded in the Darling Range between Darlington and Kalamunda. Its range may extend as far south as Harvey and it has bred at both Pinjarra and Guildford.
Damage
An increase in the number of sulphur-crested cockatoos in Western Australia would result in significant damage to grain and other crops and have negative effects on native bird species.
In eastern Australia the sulphur-crested cockatoo is a pest of grain crops. In parts of New South Wales it is a pest to fruit, pea and sweet corn growers, and feeds on almonds and grapes and chews off the young shoots of vines. In Victoria it damages vines and orchards, nut crops, vegetable, cereal and oilseed crops, young tree plantations and mature trees.
In Victoria, sulphur-crested cockatoos frequently cause widespread and costly damage to the soft timbers on houses and other structures, and to managed grass surfaces including golf courses, bowling greens, tennis courts, ovals and racecourses. Large flocks may also create a noise nuisance as they begin calling before dawn and may call during the night.
Sulphur-crested cockatoos would compete for food with the endangered western long-billed corella in the south of the state, in the 25 mm rainfall belt. Competition for nests would also occur between the sulphur-crested cockatoo and the corella as well as the native white-tailed and red-tailed black cockatoos.
Legal status
In WA, the sulphur-crested cockatoo is a Declared Pest under section 22 of the Biosecurity and Agriculture Management Act 2007 (BAM Act) administered by the Department of Primary Industries and Regional Development (DPIRD). DPIRD has a position of exclusion and management for areas south of the 20o parallel of the state. Birds in the wild are regularly removed to keep wild flocks in check. Sulphur-crested cockatoos are excluded and can only be kept as a pet with a BAM Act permit in the south of WA. A permit is not required north of the 20o parallel, as the species is native to this area. Only family pets can be imported into WA.
The Western Australian Organism List (WAOL) contains information on the area(s) in which this pest is declared and the control and keeping categories to which it has been assigned in Western Australia (WA). Use the links on this page to reach sulphur-crested cockatoo in WAOL.
Further information
For further information on sulphur-crested cockatoos, contact the Pest and Disease Information Service.