Butler's Corella
Encyclopedia
Butler's Corella is a medium-sized white cockatoo
endemic to Western Australia
. It is one of two subspecies
of the Western Corella
.
, the nominate subspecies of the Western Corella.
and farmland
where there are nearby trees for roosting in. It has benefited from agricultural development with access to food from cereal crops and permanent water.
and Double Gee
, as well as the corm
s of Onion Grass
and insect
larva
e.
s, including Wandoo
and Salmon Gum
s. Eggs are laid from August to October with a clutch size of 1-4 (averaging 2.7). The incubation period lasts 24–29 days, following which the chicks remain in the hollow for about 60 days until fledging.
After fledging, the young birds begin to forage for themselves in 2–3 weeks but continue to be dependant on their parents for another 6 months, moving with them in family groups to feeding areas and roosts. They do not start breeding until they are 3–5 years old.
Because flocks sometimes cause damage by defoliating trees, by digging up lawn
s, sports grounds
and race track
s, by chewing wiring and house fittings, and by being very noisy, the subspecies is a declared pest of agriculture. Birds may be destroyed where they are considered a nuisance.
Cockatoo
A cockatoo is any of the 21 species belonging to the bird family Cacatuidae. Along with the Psittacidae and the Strigopidae , they make up the parrot order Psittaciformes . Placement of the cockatoos as a separate family is fairly undisputed, although many aspects of the other living lineages of...
endemic to Western Australia
Western Australia
Western Australia is a state of Australia, occupying the entire western third of the Australian continent. It is bounded by the Indian Ocean to the north and west, the Great Australian Bight and Indian Ocean to the south, the Northern Territory to the north-east and South Australia to the south-east...
. It is one of two subspecies
Subspecies
Subspecies in biological classification, is either a taxonomic rank subordinate to species, ora taxonomic unit in that rank . A subspecies cannot be recognized in isolation: a species will either be recognized as having no subspecies at all or two or more, never just one...
of the Western Corella
Western Corella
The Western Corella formerly known as the Western Long-billed Corella, is a species of white cockatoo endemic to south-western Western Australia.-Taxonomy:...
.
Description
Butler's Corella has mainly white plumage with a distinct white crest. The undersides of the wings and tail are pale yellow. The feathers between the eye and beak are deep salmon-pink, as are the bases of the feathers on the head and underparts. The eye is surrounded by a broad grey-blue eye-ring. The white plumage is often stained with soil because of the birds’ foraging activities. The corellas range from 40–48 cm in length and 600–750 g in weight. They are very similar in appearance to Muir's CorellaMuir's Corella
Muir's Corella is a stocky, medium-sized white cockatoo endemic to Western Australia. It is the threatened nominate subspecies of the Western Corella.-Description:...
, the nominate subspecies of the Western Corella.
Distribution and habitat
Butler's Corella is found in the northern and central wheatbelt of south-west Western Australia. Its habitat is open woodlandWoodland
Ecologically, a woodland is a low-density forest forming open habitats with plenty of sunlight and limited shade. Woodlands may support an understory of shrubs and herbaceous plants including grasses. Woodland may form a transition to shrubland under drier conditions or during early stages of...
and farmland
Arable land
In geography and agriculture, arable land is land that can be used for growing crops. It includes all land under temporary crops , temporary meadows for mowing or pasture, land under market and kitchen gardens and land temporarily fallow...
where there are nearby trees for roosting in. It has benefited from agricultural development with access to food from cereal crops and permanent water.
Behaviour
Butler’s Corella is gregarious and may be seen in large flocks of up to several thousand birds.Feeding
The corellas feed extensively on the seeds of cereal crops, the seeds of weeds such as Cape WeedArctotheca calendula
Arctotheca calendula is a plant commonly known as cape weed, cape dandelion, or cape marigold because it originates from the Cape Province in South Africa...
and Double Gee
Emex australis
Emex australis, commonly known as doublegee or three-cornered jack, is a herbaceous plant of the Polygonaceae. It is a weed in South Africa and Australia.-External links:***...
, as well as the corm
Corm
A corm is a short, vertical, swollen underground plant stem that serves as a storage organ used by some plants to survive winter or other adverse conditions such as summer drought and heat ....
s of Onion Grass
Romulea rosea
Romulea rosea is a herbaceous perennial in the family Iridaceae. It is endemic to the western Cape Province in South Africa and is naturalised in Europe, Australia, New Zealand and California in the United States. Common names include Guildford Grass, Onion Grass and Rosy Sandcrocus.It is a small...
and insect
Insect
Insects are a class of living creatures within the arthropods that have a chitinous exoskeleton, a three-part body , three pairs of jointed legs, compound eyes, and two antennae...
larva
Larva
A larva is a distinct juvenile form many animals undergo before metamorphosis into adults. Animals with indirect development such as insects, amphibians, or cnidarians typically have a larval phase of their life cycle...
e.
Breeding
The corellas nest in tree hollows of large, mature eucalyptEucalypt
Eucalypts are woody plants belonging to three closely related genera:Eucalyptus, Corymbia and Angophora.In 1995 new evidence, largely genetic, indicated that some prominent Eucalyptus species were actually more closely related to Angophora than to the other eucalypts; they were split off into the...
s, including Wandoo
Eucalyptus wandoo
Eucalyptus wandoo is a medium-sized tree widely distributed in southwest Western Australia.-Description:It grows as a small to medium-sized tree up to 25 metres in height. It has smooth bark, often in mottled patches of white, light grey, light brown light yellow and pink...
and Salmon Gum
Eucalyptus salmonophloia
Eucalyptus salmonophloia or the Salmon Gum is an evergreen tree native to Western Australia.Other names of this species include Wuruk or Woonert.- Habit :...
s. Eggs are laid from August to October with a clutch size of 1-4 (averaging 2.7). The incubation period lasts 24–29 days, following which the chicks remain in the hollow for about 60 days until fledging.
After fledging, the young birds begin to forage for themselves in 2–3 weeks but continue to be dependant on their parents for another 6 months, moving with them in family groups to feeding areas and roosts. They do not start breeding until they are 3–5 years old.
Status and conservation
Butler's Corella is not considered to be threatened. The population comprises some 20-30,000 birds and is gradually spreading in the south-east of its range. Average life expectancy of adults has been estimated at 17 years for males and 14 years for females. However, most young birds die before they reach breeding age.Because flocks sometimes cause damage by defoliating trees, by digging up lawn
Lawn
A lawn is an area of aesthetic and recreational land planted with grasses or other durable plants, which usually are maintained at a low and consistent height. Low ornamental meadows in natural landscaping styles are a contemporary option of a lawn...
s, sports grounds
Playing field
A playing field is a field used for playing sports or games. They are generally outdoors, but many large structures exist to enclose playing fields from bad weather. Generally, playing fields are wide expanses of grass, dirt or sand without many obstructions...
and race track
Race track
A race track is a purpose-built facility for racing of animals , automobiles, motorcycles or athletes. A race track may also feature grandstands or concourses. Some motorsport tracks are called speedways.A racetrack is a permanent facility or building...
s, by chewing wiring and house fittings, and by being very noisy, the subspecies is a declared pest of agriculture. Birds may be destroyed where they are considered a nuisance.