| Gouldian Finch | |
|---|---|
| Adult Red-headed male | |
| Conservation status | |
| Scientific classification | |
| Kingdom: | Animalia |
| Phylum: | Chordata |
| Class: | Aves |
| Order: | Passeriformes |
| Family: | Estrildidae |
| Genus: | Erythrura |
| Species: | E. gouldiae |
| Binomial name | |
| Erythrura gouldiae (Gould, 1844) |
|
| Distribution of the Gouldian Finch | |
| Synonyms | |
|
Chloebia gouldiae |
|
The Gouldian Finch, Erythrura gouldiae (or Chloebia gouldiae), also known as the Lady Gouldian Finch, Gould's Finch or the Rainbow Finch, is a colorful passerine bird endemic to Australia. There is strong evidence of a continuing decline, even at the best-known site near Katherine in the Northern Territory. Large numbers are bred in captivity, particularly in Australia. In the state of South Australia, National Parks & Wildlife Department permit returns in the late 1990s showed that over 13,000 Gouldian Finches were being kept by aviculturists. If extrapolated to an Australia-wide figure this would result in a total of over 100,000 birds. In 1992, it was classified as "Endangered in the wild" under IUCN's criteria C2ai. This was because the viable population size was estimated to be less than 2,500 mature individuals, no permanent subpopulation was known to contain more than 250 mature individuals, and that a continuing decline was observed in the number of mature individuals. It is currently subject to a conservation program.
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The Gouldian Finch was described by British ornithological artist John Gould in 1844 and named after his wife Elizabeth. It is also known in America as the Rainbow Finch, Gould's Finch, or the Lady Gouldian Finch (although Mrs. Gould did not hold the title Lady). In Australia, it is predominantly called the Gouldian Finch. It is a member of the weaver-finch family Estrildidae, which is sometimes considered a subfamily of Passeridae.
Origin and phylogeny has been obtained by Antonio Arnaiz-Villena et al.[2] Estrildinae may have originated in India and dispersed thereafter (towards Africa and Pacific Ocean habitats).
Both sexes are brightly colored with black, green, yellow, and red markings. The females tend to be less brightly colored. One major difference between the sexes is that the male's chest is purple, while the female's is a lighter mauve.
Gouldian Finches are about 130–140 mm long. Gouldian Finches' heads may be red, black, or yellow. Formerly considered three different kinds of finches, it is now known that these are colour variants that exist in the wild.[3] Selective breeding has also developed mutations (blue, yellow and silver instead of a green back) in both body and breast color.
Juveniles also have distinctive colors. Their heads, sides and necks are grey, and their backs, wings and tail feathers are olive green. Their undersides are pale brown. Beaks are blackish with a reddish tip. Their legs and feet are light brown. Newly-hatched Gouldian Finches are pink and naked until about 12 days old when the beginnings of feathers start to appear. Very young birds also have blue, phosphorescent beads on the sides of their beaks to help their parents see them in the dark.
This bird is found in northern Australia, from the Cape York Peninsula through north-west Queensland and the northern Northern Territory to the Kimberley region of Western Australia. Their habitat is tropical savanna woodlands. The birds are nomadic within a relatively small area (approximately 40 square kilometers) and only move when water or food becomes scarce. The largest known wild population of the species is found in the Bastion Hills, next to the town of Wyndham in the eastern Kimberley, where a 28 km2 site – the Wyndham Important Bird Area – has been identified by BirdLife International.[4]
Prior to the Australian government's ban on the export of Australian fauna in 1959, Gouldian Finches were exported worldwide. These birds have resulted in viable breeding populations being held in many countries.
Captive breeding has resulted in a number of colour mutations being established. These include blue-back, pastel, silver, yellow-back, white-breasted, and even pure white specimens.
The number of Gouldian Finches has decreased quite dramatically during the 20th century. Their habitat has been reduced or altered. Early research indicated a parasite called the air sac mite was responsible for the decline of the species. This is no longer considered to be a major factor. In general, Gouldian Finches are susceptible to diseases and viral infections. Their beautiful colours mean that they are easily caught by predators. Fires are listed as the primary threat to the natural populations. The total number of Gouldian Finches altogether is not low, however, because they are among the most popular pet birds, and are bred in captivity for the pet trade.
Recovery plans are in place to recover and conserve its natural habitats, such as building protective fencing to prevent damage by cattle. Attempts at reintroduction have so far proved unsuccessful. It was also suggested to develop management guidelines for land-holders about appropriate land management, promoting the recovery program, and Gouldian Finch conservation.
BirdLife International has identified the following sites as being important for Gouldian Finches: [5]
Although often bred in a colony in captivity, in the wild, the Gouldian is not a colony bird. Outside the breeding season, however, Gouldian Finches often join mixed flocks consisting of Long-tailed Finches and Masked Finches. This is probably a defense against predation. Flocks used to consist of up to 1,000–2,000 individuals. During the breeding season they are usually found on rough scree slopes where vegetation is sparse. In the dry season, they are more nomadic and will move to wherever there is food and water.
Like other finches, the Gouldian Finch is a seed eater. During the breeding season, Gouldian Finches feed mostly on ripe or half-ripe grass seeds of sorghum. During the dry season, they forage on the ground for fallen seed. During the wet season, spinifex grass seed (Triodia sp.) is an important component of their diet. So far Gouldians have been recorded as consuming six different species of grass seed, but during crop analysis, researchers have yet to find evidence of insect consumption.
Gouldian finches generally make their nests in tree-holes, generally within a kilometer or so of water. They usually breed in the early part of the dry season, when there is plenty of food around. The male courtship dance is a fascinating spectacle. When a male is courting a female, he bobs about ruffling his feathers to show off his colors. He expands his chest and fluffs out his forehead feathers. After mating, a female lays a clutch of about 4–8 eggs. Both parents help brood the eggs during the daytime, and the female stays on the eggs at night. When the eggs hatch, both parents help care for the young. Gouldian Finches leave the nest at between 19 and 23 days and are independent at 40 days old.
Gouldian finches have brightly coloured gapes and call loudly when the parent birds return so that they are able to find and feed their mouths in the dark nest.[6]
Young Gouldians are very fragile until their final moult. Some breeders believe parent-raised Gouldians have greater success rearing young than those fostered by other species, such as Society finches or Spice Finches.
It has been shown scientifically that female finches from Northern Australia are controlling the sex of their offspring, according to the head color of their male counterpart. Gouldian Finches should not be mated with Gouldian Finches of a different head color (black-head with red-head etc.) as such a mating will result in an imbalance in the sex ratio of the young, with a greater proportion of male offspring being produced.[7][8][9]
They need premium finch food, fresh water every day, gravel, a cuttlebone, perches, vitamins (the blue-blacked ones cannot produce their own vitamin A). They especially need vitamins in their soft food. Water should be changed every day. Gravel should be replaced once a month and whole cage should be cleaned and disinfected. The Gouldian finch can be difficult to breed outside its native climate of Australia but does well when given the right conditions. Grit and cuttlebone are an important component of a finch's diet.
Many mutations occur in aviculture, including yellow, dilute, blue, silver, white and even albino Gouldian Finches.
Gouldian finches are used as the ViewSonic logo, composed of three birds perched on a greenish branch.
In the 1992 movie Batman Returns, the bird Catwoman puts in her mouth is a Gouldian finch.
David Attenbourgh, The Life of Birds, Episode 9, 3 mins, 55 secs