Cacatua galerita

Geographic Range

Cacatua galerita is native to the Australian Region and occurs in large numbers in the north and east of Australia. It has been introduced to western Australia, New Zealand and New Guinea.

• Biogeographic Regions
• australian australian
  • introduced introduced
  • native native
• oceanic islands oceanic islands
  • introduced introduced

Habitat

Sulphur-crested cockatoos dwell in a variety of timbered habitats such as tropical and subtropical rainforests. They are also found in the vast savannas of northern Australia. Sulphur-crested cockatoos also occur in suburban and urban areas, especially in parks and gardens.

• Habitat Regions
• tropical tropical
• terrestrial terrestrial

• Terrestrial Biomes
• savanna or grassland savanna or grassland
• forest forest

• Other Habitat Features
• urban urban
• suburban suburban

Physical Description

Sulphur-crested cockatoos are large birds, measuring 45 to 50 centimeters in length. Their average weight is 800 grams. Sulphur-crested cockatoos are white with a distinctive sulphur-yellow crest which can be erected or held folded down on top of head. The underside of their wings and tail is pale yellow. Females and males are similar in appearance (monomorphic); however, females can be identified at close range by their red tinted brown eyes, whereas males have darker brown eyes. There are four subspecies of sulphur-crested cockatoos. Cacatua galerita fitzroyi differs from C. g. galerita in having a pale blue eye ring instead of white, the yellow feathers are slightly darker, and the crest feathers are longer. Cacatua galerita eleonora and C. g. triton both average smaller in overall size than C. g. galerita .

• Other Physical Features
• endothermic endothermic
• homoiothermic
• bilateral symmetry bilateral symmetry

• Sexual Dimorphism
• sexes colored or patterned differently

Reproduction

Sulphur-crested cockatoos are monogamous birds. Signs of courtship include raising of the crest, bobbing of the head, and moving the head from side to side in a figure-of-eight pattern while uttering soft chattering notes. Before mating, the birds usually preen each other's plumage.

• Mating System
• monogamous monogamous

In the northern parts of their range, sulphur-crested cockatoos breed from May to September, whereas birds in the southern parts of their range breed from August to January. They generally nest in a high tree hollow, usually near water. They breed once yearly, producing a clutch containing 2 to 3 white oval eggs. Eggs hatch after an incubation period of 27 to 30 days. Fledging generally occurs at approximately 70 days. Offspring will leave the nest after this 70 day period but will remain with the parents year round. Family units will remain together indefinitely. Both male and female Cacatua galerita reach reproductive maturity around the age of 3 to 4 years.

• Key Reproductive Features
• iteroparous iteroparous
• seasonal breeding seasonal breeding
• gonochoric/gonochoristic/dioecious (sexes separate)
• sexual sexual
• oviparous oviparous

Both parents incubate their clutch. Once the eggs hatch, chicks are fed by both parents.

• Parental Investment
• altricial altricial
• pre-fertilization
  • provisioning
  • protecting
    • female
• pre-hatching/birth
  • provisioning
    • female
  • protecting
    • male
    • female
• pre-weaning/fledging
  • provisioning
    • male
    • female
  • protecting
    • male
    • female
• pre-independence
  • provisioning
    • male
    • female
  • protecting
    • male
    • female
• post-independence association with parents

Lifespan/Longevity

Sulphur-crested cockatoos can live for decades in the wild. Average lifespan is about 40 years, but they can live up to 100 years. In captivity, sulphur-crested cockatoos that are well-cared for can live for 65 years on average and up to 120 years.

Behavior

Cacatua galerita is a gregarious species, often forming flocks of a dozen to several hundred birds. When foraging for food these large flocks will often split into small groups, coming together again at the evening roost site. Feeding is often done on the ground, and in such situations some of the flock will be sentry birds in trees, and alert the flock of approaching danger. Sulfur-crested cockatoos generally stay sheltered during the middle of the day, resuming feeding in late afternoon and evening before drinking and returning to roost.

The distinctive raucous call of C. galerita is very loud; it is meant to travel great distances through the forested environment. The cacophony created by a large flock of sulphur-crested cockatoos can be deafening.

• Key Behaviors
• arboreal arboreal
• flies
• diurnal diurnal
• motile motile
• sedentary sedentary
• social social

Home Range

Cacatua galerita often travel long distances in a day to forage, almost always returning to their original roost site. Sulphur-crested cockatoos remain in the same general area year round. The exact home range size of C. galerita is not well documented.

Communication and Perception

Sulphur-crested cockatoos are noisy birds. Their primary method of communication is their screeching voices. They also use their crest to communicate emotion. They will raise and spread their magnificent crests when excited, such as when danger is detected or during mating.

• Communication Channels
• visual visual
• acoustic acoustic

• Other Communication Modes
• mimicry mimicry

• Perception Channels
• visual visual
• tactile tactile
• acoustic acoustic
• chemical chemical

Food Habits

Sulphur-crested cockatoos are primarily granivores in the wild, feeding both on the ground and in trees. They feed mainly on seeds, nuts, fruits, blossoms, insects and insect larvae. They will also attack newly planted and ripening grain crops.

In captivity, C. galerita are mainly fed a diet of fresh fruits, vegetables, seeds, nuts, pellets, legumes and grains. They have a high rate of obesity so high fat foods such as peanuts and seeds are fed sparingly.

• Primary Diet
• herbivore herbivore
  • frugivore frugivore
  • granivore granivore

• Animal Foods
• insects

• Plant Foods
• seeds, grains, and nuts
• fruit
• flowers

Predation

Sulphur-crested cockatoos have one primary method of detecting and avoiding predators. When feeding, a few 'sentinel' birds will perch in a tree looking out for predators. They unleash their deafening warning call when a potential predator is sighted. Their large size also protects them from predation by all but the largest birds of prey.

During the incubation period and 6 to 10 weeks thereafter, both parent birds are intentionally very quiet in order not to attract predators to their nest.

Sulphur-crested cockatoos are known to be preyed on by powerful owls ( Ninox strenua ). Goannas ( Varanus ) are also potential predators of birds on the ground, fledglings, and nestlings. Other potential predators include common avian nest predators such as pied currawongs ( Strepera graculina ), butcherbirds ( Cracticus ), and ravens.

Ecosystem Roles

The role of sulphur-crested cockatoos in the ecosystems they inhabit is not well documented. They feed on seeds and nuts and may play a role in seed dispersal.

• Ecosystem Impact
• disperses seeds

Economic Importance for Humans: Positive

Sulphur-crested cockatoos are popular pets and companion birds. Their yellow feathers have been used in ceremonial headdresses.

• Positive Impacts
• pet trade pet trade
• ecotourism ecotourism

Economic Importance for Humans: Negative

Sulphur-crested cockatoos can be so numerous in crop growing areas that they are often shot or poisoned as pests. Government permit is required, though, as they are a protected species under the Australian Commonwealth Law. Aside from crops, they can also be harmful to wooden structures and ornamental trees as they chew and rip at timber on houses and tree limbs.

• Negative Impacts
• crop pest

Conservation Status

Sulphur-crested cockatoos are generally common and abundant. Their population is approximated at more than 500,000 individuals. It is no longer legal to import these birds to the United States as a result of the Wild Bird Conservation Act.

Additional Links

Encyclopedia of Life

Contributors

Tanya Dewey (editor), Animal Diversity Web.

Kyle Thomas (author), Kalamazoo College, Ann Fraser (editor, instructor), Kalamazoo College.

References

Bell, A. 1969. Common Australian Birds . London: Oxford University Press.

Berra, T. 1998. A Natural History of Australia . San Diego, CA: Academic Press.

Cody, M. 1993. Bird diversity components within and between habitats in Australia. Pp. 147-158 in Species Diversity in Ecological Communities: Historical and Geographical Perspectives . Chicago, IL: The University of Chicago Press.

Dobbs, S., C. Highfill. 2003. "Birds n Ways" (On-line). Accessed October 12, 2006 at http://www.birdsnways.com/cockatoo/sc.htm .

Forshaw, J. 2002. Parrots. Pp. 275-298 in Grzimek's Animal Life Encyclopedia , Vol. Volume 9, Second Edition. Detroit: Gale.

Perrins, D. 1990. The Illustrated Encyclopedia of Birds . New York: Prentice Hall Press.

Sibley, C., B. Monroe. 1990. Distribution and Taxonomy of Birds of the World . New Haven: Yale University Press.

Cambridge University Press. 1991. Pp. 33 in The Cambridge Encyclopedia of Ornithology . Cambridge: Cambridge University Press.

Equinox. 1985. Pp. 220-230 in The Encyclopedia of Birds . New York: Facts on File, Inc..

Australian Museum. 2003. "Australian Museum" (On-line). Factsheets: Sulphur-crested cockatoo. Accessed October 12, 2006 at http://www.amonline.net.au/factSheets/sulphur_crested_cockatoo.htm .

2006. "IUCN 2006" (On-line). 2006 IUCN Red List of Threatened Species. Accessed October 13, 2006 at http://www.iucnredlist.org .