![]() In Nature, the Gouldian finch is more vulnerable to drought during a moult than other co-occurring finch species because it is moulting at a time when seed shortages may occur (Woinarski and Tidemann 1992). The rapid moult of Gouldian finches appears to be an evolutionary adaptation to an unpredictable climate and tropical woodland breeding environment where there is a need to complete a moult before the end of the dry season (when seed shortages are frequent) and prior to arrival of the wet season (when torrential rains reduce foraging activity and curtail Gouldian finches' ability to fly long distances in search of alternative food supplies). 1998), and thought to reflect the more mobile and dispersive nature of the Gouldian finch (Tidemann and Woinarski 1994). The time taken for the Gouldian finch to complete the moult is rapid compared to co-occurring masked and long-tail finches (Franklin et al. The moult period finishes in November close to a period when seed shortage can occur (Tidemann & Woinarski 1994). Most of the wing flight feathers are replaced during October (Milton Lewis 2001). Gouldian finches (both adults and juveniles) moult during September, October & November (Milton Lewis 2001). The seasons across their tropical range are described as the wet season and dry season, the start and end of which may vary from one year to the next. The moult of Gouldian finches is an annual seasonal event with a starting time that may vary slightly depending upon local climatic conditions. The annual replacement of flight feathers is therefore critical to their survival. Gouldian finches are stronger flyers than other co-occurring finches (Long-tailed and Masked Finches) and able to fly long distances in search of food (Tidemann & Woinarski 1994). ![]() This paper discusses the compressed moult of Gouldian finches, its relationship to airsac mite infection and possible link to its decline in Nature. 1998) but the manner in which a rapid completion may be achieved through a compressed moult has not been presented. The moult of the Gouldian finch is known to be more rapid than other co-occurring finches (Franklin et al. tracheacolum might be exacerbated during periods of physiological stress associated with the moult and food shortages at the onset of the wet season (Lane & Goodfellow 1989 cited in O'Malley 2006a O'Malley 2006). It has been speculated that the impact of S. tracheacolum might have had, and might continue to have, a negative effect on the Gouldian Finch population. Airsac mite infections have also been thought to play a role in the decline of the species (Tidemann & Woinarski 1994).Īlthough reduced availability of critical wet season grass seed resources due to changes in land use and consequent changes in grazing and fire regimes, combined with natural fluctuations in seasonal rainfall is thought to be involved with the decline of the Gouldian Finch in its natural environment, as yet there is no clear link between resource scarcity and its endangered status (Dostine and Franklin 2002 Fraser 2000 Crowley and Garnett 1994). Ī decline in wild populations of Gouldian finches has been attributed to a restricted diet and seed shortages during the moult (Dostine et al 2002). In the Gouldian finch ( Erythrura gouldiae ). To Airsac Mite (Sternostoma tracheolum) Infection
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