NT
Gouldian Finch Chloebia gouldiae



Justification

Justification of Red List Category
This species has been downlisted to Near Threatened because past population declines appear to have ceased, despite ongoing threats from grazing and fire management. Nevertheless, the total population remains small and is precautionarily suspected to contract to approaching 1,000 mature individuals at the end of the dry season.

Population justification
The population has been conservatively estimated to be fewer than 2,500 mature individuals at the start of the breeding season, however more optimistic estimates have placed the total population as closer to c.10,000 mature individuals (J. Woinarski in litt. 2007).  A large proportion of flocks are however juveniles, there is a strong male biased sex ratio and genetic incompatibility between colour morphs (S. Pryke in litt. 2012) making a precautionary estimate important. The results of an expert panel review process concluded that the most plausible population size was c2,400 mature individuals in 2010, which potentially falls to an annual minimum close to 1,000 individuals during the wet season (Garnett et al. 2011).

Trend justification
Past declines appear to have ceased and, despite potential ongoing threats to its habitat from from grazing and fire management, the population is estimated to be stable (Garnett et al. 2011).

Distribution and population

Erythrura gouldiae is found in northern Australia, with scattered records from Cape York Peninsula through north-west Queensland, but there are more records from the northern region of the Northern Territory to the Kimberley region of Western Australia. In Queensland, it is only known with regularity from one site, although there are irregular reports from elsewhere in its former range. Birds are more numerous in the Northern Territory and Western Australia. The population has been conservatively estimated to be fewer than 2,500 mature individuals at the start of the breeding season, however more optimistic estimates have placed the total population as closer to c.10,000 mature individuals (J. Woinarski in litt. 2007). The results of an expert panel review process concluded that the population was c2,400 mature individuals in 2010, which potentially falls to an annual minimum close to 1,000 individuals during the wet season (Garnett et al. 2011). Monitoring of the population size at the best-known site near Katherine has demonstrated population stability (O. Price per Woinarski in litt. 2007). Similarly, monitoring at Mornington Wildlife Sanctuary in central Kimberley has shown no evidence of a decline over four years from 2004 to 2007 (S. Legge in litt. 2007), and the overall population is estimated to be stable or increasing (Garnett et al. 2011). Accurately determining overall population trends is however difficult due to the scale and erratic nature of the birds' movements (S. Legge in litt. 2012).

Ecology

It lives in open, tropical woodland with a grassy understorey, nesting almost exclusively in tree-hollows. Known breeding habitat in the Northern Territory and Western Australia is characterised by rocky hills with smooth-barked gums Eucalyptus brevifolia or E. tintinnans within two to four kilometres of small waterholes or springs that persist throughout the dry season (O'Malley 2006). In the non-breeding season, it may occur in a slightly wider variety of woodland habitats. Throughout the year, it feeds mostly on grass seeds, sometimes taking invertebrates (S. Legge in litt. 2007). Dry season feeding habitat is dominated by annual spear grasses or native sorghum Sarga species (O'Malley 2006). In the wet season birds shift to scattered patches of cockatoo grass Alloteropsis semialata, golden beard grass Chysopogon fallax or spinifex Triodia-dominated communities. Other important wet season grasses include giant spear grass Heteropogon triticeus, white grass Sehima nervosum, ricegrass Xerochloa laniflora and kangaroo grass Themeda triandra (O'Malley 2006). The range of the Gouldian finch can change substantially, possibly related to the high mobility of the species, or the fluctuations in range between years (S. Pryke in litt. 2012).

Threats

Grazing and altered fire regimes are thought to be the main threats. Cattle and other livestock cause changes in grass species composition and phenology, with the most severe impact probably due to a reduction in the abundance of grass species that set seed earliest in the wet season (J. Woinarski in litt. 2007). Wet season grasses that are essential to the species are grazed by cattle, horses and feral pigs, whilst cattle and buffalo can degrade waterholes used by the species through trampling and grazing of the surrounding vegetation (O'Malley 2006). Current fire regimes may be exacerbating the impact of herbivores, obliterating the mosaics of burnt and unburnt habitat the birds require. Fire is known to impact the seed productivity of key wet season grasses that the species relies on during the period of food scarcity that occurs early in the year, and the species also tends not to nest in burnt tree-hollows (O'Malley 2006). The modern fire regime in northern Australia is dominated by frequent, extensive, hot, late dry season wildfires over large tracts of land (O'Malley 2006). Research by Legge et al. (2015) showed indices of body condition to be lower for individuals exposed to extreme fire regimes, compared to their counterparts in less frequent and less intense fire regions. These differences in body condition suggest increased activity to find food, greater food uncertainty and prolonged food deprivation. Trapping may have had a local effect in the past. Infection with the parasitic mite Sternostoma tracheacolum was long thought to be one of the principal reasons for decline. However, it is now considered that it may be indicative of stress to the birds resulting from a broader change at the landscape level that has affected a range of granivore species. Nevertheless, recent short-term increases may represent recovery after an epidemic of the mite (S. Garnett in litt. 2007). The impacts of climate change are hard to determine: the species is projected to have an increase in suitable climate space by the end of the century (Reside et al. 2012, 2015) but climate change is predicted to affect the timing and quantity of wet season rainfall, potentially increasing the frequency or intensity of wildfires, altering the abundance of important grass species and changing the availability of surface water during the dry season (O' Malley 2006)

Conservation actions

Conservation Actions Underway
Management actions completed or under way include the implementation of a recovery plan, the establishment of regional operations groups, detailed research on fire, food and movements at Mornington Wildlife Sanctuary, Kimberley, the collation and maintenance of a database of all known sight records and a review of the patterns of the distribution, habitats, potential threats and conservation status of savanna granivorous birds. Attempts at reintroduction have so far had equivocal results (S. Garnett in litt. 2007). There is an ongoing monitoring programme at four sites (J. Woinarski in litt. 2007, S. Legge in litt. 2007) and captive-breeding populations exist (SPRAT profile 2013).

Conservation Actions Proposed
Define the response of grasses and E. gouldiae to a range of pastoral and fire management regimes (O'Malley 2006, J. Woinarski in litt. 2007). Work with landholders to implement those management regimes that are neutral or beneficial (O'Malley 2006, J. Woinarski in litt. 2007). Monitor abundance at key sites throughout its current range, and responses to enhanced management (J. Woinarski in litt. 2007). Installations of nest-boxes could be used to increase reproduction in recovering populations (Brazill-Boast et al. 2013). Extend the captive breeding programme and promote the recovery programme, evaluating performance. Control feral herbivores (O'Malley 2006). Work with the Jawoyn Aboriginal Corporation in implementing fire regimes and control of feral herbivores (O'Malley 2006). Refine reintroduction methods and investigate factors limiting survival through trial reintroductions at sites in Queensland (O'Malley 2006). Disseminate information on the recovery programme to stakeholders (O'Malley 2006).

Identification

11-12.5 cm. Gaudy finch with pointed, black tail. Adult is among the most colourful of birds. Grass-green upper body from lower nape to back and wings, browner remiges. Black, red, or rarely, orange-yellow head and throat, narrowly bordered posteriorly with black and pale blue. Pale blue rump. Purple breast. Bright yellow belly. Whitish bill with red tip. Female duller on underside. Juvenile ashy-grey on head and neck, paler below and olive-grey on upper body and wings. Similar spp. Adult unmistakable. Juvenile more olive and bulkier than other finches. Voice Sibilant sitt, repeated. Hints Gather at waterholes to drink in dry season.

Acknowledgements

Text account compilers
Benstead, P., Garnett, S., McClellan, R., Symes, A., Taylor, J., Temple, H., North, A.

Contributors
Brazill-Boast, J., Legge, S., Garnett, S., Woinarski, J.


Recommended citation
BirdLife International (2017) Species factsheet: Chloebia gouldiae. Downloaded from http://www.birdlife.org on 23/11/2017. Recommended citation for factsheets for more than one species: BirdLife International (2017) IUCN Red List for birds. Downloaded from http://www.birdlife.org on 23/11/2017.