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Size and Weight: Length is about 50 cm (20 inches). Their
wingspan is about 60-80 cm (23-31 inches) and they may weigh up
to 900 gms (2 lbs).
Diet: Sulphur-crested Cockatoos eat seeds, fruits, berries,
nuts, flowers, leaf buds and insect matter. They also plague farmers
by eating newly sprouted seeds and raiding crops as they ripen.
They may also help themselves to bagged grain. They also eat the
seeds of many weed species but their damage to crops outweighs
their benefit at controlling weeds.
Habitat and Distribution: This species is common in a
wide variety of wooded and savannah habitats in New Guinea, northern
and eastern Australia, and Tasmania usually near water.
Status in the Wild: This is an extremely common bird that
is regarded as an agricultural pest because of the heavy toll
flocks take on agricultural fruit and cereal crops. Losses of
between 50-90% of peas, safflower, maize and sunflower along with
the continued growth of bird populations has left farmers in a
difficult position and has led to the slaughter of thousands of
birds by poisoning, trapping, clubbing and shooting.
Status in Captivity: In the United States this species
is still expensive and sought after as a pet. Due to an exportation
ban out of Australia, they are still not extremely common in private
hands outside of Australia. Certain breeders have had great success
breeding them but it is difficult to ascertain the genetic background
as there are so many subspecies.
Habits and Adaptations: During the breeding season, Sulphur-crested
Cockatoos seem to congregate in pairs or small groups. At other
times they associate in large flocks of hundreds of birds. In
flight, these beautiful white parrots show yellow underwing linings
and often screech loudly. They often feed on the ground and employ
a reliable sentinel system to warn feeding birds of approaching
danger. Birds perched on the periphery of the foraging flock will
scream and take flight, the rest of the flock rising to escape
with them. When relaxed or "happy" the feathers of the
cheeks are extended to cover the lower mandible.
Breeding and Maturation: Nests are found primarily in
hollows of eucalypt or other high trees, often near water. The
2-3 white eggs require about 30 days incubation and are brooded
by both sexes. The young fledge after 6-9 weeks. In captivity,
they wean slowly and often display begging behavior for up to
2 years.
Lifespan: This species could probably live up to 50 years
or more. Some of the longest lived of all pet birds are cockatoos
who have lived to be 80 years old or more.
Conservation Issues: The slaughter of this any other cockatoo
species due to the crop damage they inflict cannot be overlooked
by any means. Images of these intelligent birds being clubbed
or otherwise killed are difficult to accept. Lifting the export
ban may make some inroads towards both filling the demand for
these birds as pets in the United States and Europe and in lowering
numbers of birds raiding crops. Still, there is hardly a market
for millions of these birds in the breeding cages of the aviculture
community and truly only the hand-raised progeny of these wild-caught
birds will make suitable pets for the average customer. There
are valid arguments both for and against exportation. Like most
conservation issues, this one is not easily solved.
Bibliography
Axelson, R. 1989. Caring for your Pet Bird. Sterling Publishing
Co., Inc. New York.
Forshaw, J. 1973. Parrots of the World. Lansdowne Press, Australia.
Low, R. 1986 Parrots: Their Care and Breeding. Revised and Expanded
edition. Blandford Press, Ltd.
Maranville, C. and Beane, C. 1987. Which Cockatoo is for you?
BirdTalk, June 1987, p 52-61.
Rhea, M. 1988. Australian Cockatoos- Pests or Pets? BirdTalk,
April 1988, p. 26-31.
Slater, P., Slater, P., and Slater, R. 1989. The Slater Field
Guide to Australian Birds. Landsdowne Publishing, Australia.
Photo: By Steve Parish for Steve Parish Publishing Co., Australia
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