Gouldian Finch
Tagged: animal, animals, bird, catErythrura gouldiae
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Once abundant and widespread over much of northern Australia, the beautiful and colorful Gouldian finch is greatly reduced in numbers and breeding sites, due mainly to habitat changes. Records suggest that in the early 20 th century the Gouldian finch was a common and familiar member of its family with an extensive range. During the 20 th century, however, the species suffered a dramatic decline both in numbers and distribution. During the 1960s a survey at Pine Creek, Cape York, Australia, caught about 1,000 individuals in one week. A second survey in the same area in 1996 found only half a dozen birds in three months. It is not surprising that such a stunning-looking bird was popular with cage-bird enthusiasts. Large numbers were caught legally and illegally-for the Australian and international trade in captive birds until the early 1980s. The numbers of birds legally caught each year by licensed bird trappers were recorded until the end of 1986, when the trapping of Gouldian finches was banned. The statistics showed that between 1972 and 1981 there was an 87 percent decline in numbers caught in Western Australia were caught commercially. Large-scale trapping is likely to have depleted populations, but landscape changes are thought to be much more significant. . At the end of this period-five years before the trapping ban-no Gouldian finchesGouldian finches are primarily birds of open tropical woodland with a grassy understory, where they are highly selective both in their diet and choice of breeding sites. They feed exclusively on grass seeds; the grass species varies seasonally and geographically. The birds travel over large distances to find supplies to build up their reserves before breeding.
Environmental Change
Gouldian finches are the only members of their family to nest almost exclusively in tree hollows rather than building their own nests. Highly sociable, they breed in loose colonies, preferring clumps of smooth-barked eucalyptus trees, although the species of eucalyptus varies from area to area. At present none of the known breeding sites has long-term protection as a nature reserve. The Gouldian finch’s dependence on a specialized diet makes it sensitive to changes in land management, especially the burning of grasses by farmers. Low-intensity fires during the dry season can help the birds find food: Fallen seed is more accessible to the birds after any covering of dead stems and leaves has been burned off. At the end of the dry season, however, intense fires burn off tree leaves, destroying suitable shelter. Fierce fires during the wet season can destroy sorghum grassland, including any emerging seedlings. Food shortages after such fires are often made worse by the fact that cattle graze the affected areas, preventing grasses from seeding. Grazing and the uniform fire regime destroy the mosaic of habitats on which the finches depend. The regular burning destroys clumps of breeding trees, and the birds are known to avoid badly burned tree hollows.
Mite Attack
A symptom of these landscape changes is the high level of infection with a parasitic mite that affects the finch’s respiratory system. When birds in captivity are infected, they wheeze and become listless, fail to breed, and die if they are not treated with antibiotics. Although the effects of the mite had not been reported in wild birds, researchers checking for its presence found it occurred in 62 percent of the birds examined. Even though the parasites were not the cause of the massive declines, they may be preventing the species from recovering its numbers.
Recovery Plan
A recovery plan for the Gouldian finch was announced in 1998. Its chief emphasis is an in-depth study of the ecology and habitat needs of the species. The main objective is to stabilize numbers. Initially the numbers and occurrence of the Gouldian finch must be determined. With a small, scarce bird with a huge range this is no easy task, although counts at waterholes have gained useful results so far.
Statistics
Gouldian finch (painted finch, rainbow finch, purple-breasted finch, Lady Gould’s finch)
Erythrura gouldiae
- Family: Estrildidae
- World population: Fewer than 2,500 adults may remain in the wild at the start of the breeding season
- Diet: Ripe and part-ripe grass seeds, mainly sorghum in dry season; seeds of other grasses in the wet season
- Distribution: Northern Australia
- Habitat: Dry savanna grassland; fringes of mangroves and thickets; rarely far from water. Woods and scrubland with spinifex grasses in wet season; avoids human habitation
- Size: Length: 5-5.5 in (12.5-14 cm). Weight: 0.4-0.5 oz (12-15 g)
- Form: Multicolored plumage in adults. Male has green upperparts with circular or oval patch on purple breast; yellow belly and flanks; black tail with long, pointed central feathers. Female duller, with shorter central tail feathers. Juveniles have gray heads and lack bright colors and long tail feathers
- Breeding: Female usually lays 4-8 white eggs directly into tree hollow or termite mound in January-April (rainy season). Incubation 12-13 days; fledging about 21 days
- Related endangered species: Green faced parrotfinch (Erythrura viridifacies) ; Shelley’s crimson-wing (Cryptospiza shelleyi) ; Anambra waxbill (Estrilda poliopareia);green avadavat (Amandava formosa)
Gouldian finches come in many color varieties. About 75 percent of birds have black faces and 25 percent have crimson heads; there is also a rare yellow-headed form.
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