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Causes of the decline of the Gouldian Finch Erythrura gouldiae

Published online by Cambridge University Press:  11 May 2010

Sonia C. Tidemann
Affiliation:
Conservation Commission of the Northern Territory, P.O. Box 496, Palmerston, NT 0831, Australia
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Summary

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Populations of Gouldian Finch Erythrura gouldiae, an estrildid endemic to northern Australia, declined markedly during the last two or three decades. A survey revealed the species in two areas of Northern Territory, with an estimated 2,000 individuals, including juveniles. Recaptures were low either because of mortality or dispersal. Gouldian Finches eat predominantly Sorghum spp. seeds, but consume other seeds before Sorghum ripens. Other finches declined as cattle increased. Gouldian Finches breed in tree hollows of predominantly two species of eucalypts that grow on rocky slopes. They require water within about 4 km of the nest site. There was no shortage of nesting hollows at the known breeding sites. Fires in the early to mid-dry season allow birds access to seed without damaging trees, but later fires can destroy trees with nest hollows and remove shade. Average clutch-size is 5.2. About 72% of eggs laid, and 63% of nests, fledged young. Pairs lay up to three clutches in a season (February-August), the length of which may depend on rainfall during the preceding wet season. Air-sac mite (Sternostoma tracheacolum), found in 62% of Gouldian Finches sampled, may be preventing the species recovering to former numbers. New colonies of Gouldian Finches should be identified, populations monitored, and habitat managed by effecting patchy burns by low-intensity fires early in the dry season.

Type
Research Article
Copyright
Copyright © Birdlife International 1996

References

Andrew, M. H. and Mott, J. J. (1983) Annuals with transient seed banks: the population biology of indigenous Sorghum species of tropical north-west Australia. Aust. J. Ecol. 8: 265276.CrossRefGoogle Scholar
Berney, F. L. (1903) North Queensland notes on some migratory birds. Emu 2: 210.CrossRefGoogle Scholar
Blakers, M., Davies, S. J. J. F. and Reilly, P. N. (1984) Atlas of Australian birds. Melbourne: Melbourne University Press.Google Scholar
Heumann, G. A. (1926) Birds in the Northern Territory and the new finch. Emu 25: 134136.CrossRefGoogle Scholar
Immelmann, K. (1982) Australian finches. Sydney: Angus and Robertson.Google Scholar
Knight, M. H. (1989) Importance of borehole water to doves and sandgrouse in the semi-arid southern Kalahari. S. Afr. J. Wildl. Res. 19: 4246.Google Scholar
Madill, D. (1987) Parasitic diseases. Pp. 4559 in Macwhirter, P., ed. Even/bird: a guide to health. Sydney: Inkata.Google Scholar
Mott, J. J. and Andrew, M. H. (1985) The effect of fire on the population dynamics of native grasses in tropical savannas of north-west Australia. Proc. Ecol. Soc. Aust. 13: 231239.Google Scholar
Schodde, R. and Tidemann, S. C., eds. (1986) Complete book of Australian birds. Sydney: Reader's Digest.Google Scholar
Tidemann, S. C. (1990) The relationship between finches and pastoral practices in northern Australia. Pp. 305315 in Pinowski, J. and Summers-Smith, J. D., eds. Granivorous birds and agriculture. Warsaw: PWPN-Polish Scientific Publishers.Google Scholar
Tidemann, S. C. (1993a) Where are the Gouldian Finches after the breeding season? Victorian Nat. 110: 238243.Google Scholar
Tidemann, S. C. (1993b) Management of a threatened species - the Gouldian Finch example. Pp. 123131 in Catteral, C. P.Driscoll, P. V.Hulsman, K.Muir, D. and Taplin, A., eds. Birds and their habitats: status and conservation in Queensland. Brisbane: Queensland Ornithological Society.Google Scholar
Tidemann, S. C., Calley, M. and Burgoyne, C. (1992a) An investigation of blood smears of northern Australian finches. Emu 92: 114117.CrossRefGoogle Scholar
Tidemann, S. C., McOrist, S., Woinarski, J. C. Z. and Freeland, W. J. (1992b) Heavy parasitism of wild Gouldian Finches Erythrura gouldiae by the air-sac mite Sternostoma tracheacolum. J. Wildl. Diseases 28: 8084.CrossRefGoogle Scholar
Tidemann, S. C., Boyden, J., Elvish, R., Elvish, J. and O'Gorman, B. (1992c) Comparison of the breeding sites and habitat of two hole-nesting estrildid finches, one endangered, n i northern Australia. J. Trop. Ecol. 8: 373388.CrossRefGoogle Scholar
Tidemann, S. C., Palmer, C., Boyden, J. and Hunt, T. (1992d) Predation on the Gouldian Finch Erythrura gouldiae by reptiles. Corella 16: 105106.Google Scholar
Tidemann, S. C., McCartney, J. and Smith, I. (1993) The Gouldian Finch and air-sac mite in Queensland. Sunbird 23: 3640.Google Scholar
Tidemann, S. C., Lawson, C., Elvish, R., Boyden, J. and Elvish, J. (in press) Breeding biology of the Gouldian Finch (Ploceidae: Erythrura gouldiae), an endangered finch of northern Australia. Emu.Google Scholar
Watkinson, A. R., Lonsdale, W. M. and Andrew, M. H. (1989) Modelling the population dynamics of an annual plant Sorghum intrans in the wet-dry tropics. J. Ecol. 77: 162181.CrossRefGoogle Scholar
Woinarski, J. C. Z. (1990) Effects of fire on the bird communities of tropical woodlands and open forests in northern Australia. Austral. J. Ecol. 15: 122.CrossRefGoogle Scholar
Woinarski, J. C. Z. and Tidemann, S. C. (1992) Survivorship and some population parameters for the endangered Gouldian Finch Erythrura gouldiae and two other finch species at two sites in tropical northern Australia. Emu 92: 3338.CrossRefGoogle Scholar
Zann, R. and Straw, B. (1984) A non-destructive method to determine the diet of seed-eating birds. Emu 84: 4041.CrossRefGoogle Scholar