Heres the BirdLife Int summary, largely taken from the Action Plan 2010 (Garnett et al. 2011). Australia is rather large, and potential habitat must around say 5,000,000 km2, though perhaps they do actually occupy tiny patches of this. Because of their cryptic nature we probably can only conclusively be certain that they are absent from tiny bits of this, but what if they do move around as suspected. Colin http://www.birdlife.org/datazone/speciesfactsheet.php?id=1491 Population justification Its remaining population is assumed to be very small, and was formerly precautionarily estimated to number fewer than 50 mature individuals based on the paucity of records. In 2010 an expert committee re-assessed this as untenable, given records from Western Australia in 2005 and Queensland in 2006, and estimated that there might be 50-250 birds in total (Garnett et al. 2011). The number of mature individuals is therefore placed in the band 50-249, but may prove to be larger. Trend justification The population is suspected to be in decline owing to a combination of threats, including predation by alien invasive predators. Distribution and population Pezoporus occidentalis is endemic to Australia, where historical records are spread throughout the arid and semi-arid zones. There were comparatively few confirmed records from the 20th century. At least five dedicated searches and two broad-scale publicity campaigns in the 1990s failed to confirm the existence of any population, with only one authenticated record from near Boulia, north-western Queensland, in 1990. However, three birds were then reported at Minga Qwirriawirrie Well near the Fortescue Marshes in the Pilbara region of Western Australia in April 2005 (Davis and Metcalf 2008). Subsequent searches in 2005 and 2006 failed to relocate the species, but this may have been because there had been recent rain, and so birds were not concentrating at the waterhole (M. J. Bamford and B. M. Metcalf in litt. 2005). There were three possible sightings at two sites 145 km apart in the East Pilbara in 2010 (Ramsay 2010). A dead bird was found by Queensland Park and Wildlife Service Rangers in Diamantina National Park, Queensland in November 2006, less than 200 km from the1990 record, having apparently collided with a fence some weeks before (Birds Australia in litt. 2007, McDougall et al. 2009). It was positively identified by Queensland Museum and appeared to be an immature, implying a breeding event in the two years prior to September 2006 (McDougall et al. 2009). Flood rains in the Channel Country have prevented access to the area for follow-up surveys (Birds Australia in litt. 2007). It seems quite likely that this cryptic species occurs at a low density elsewhere in its former range as there have been unverified sight records from inland regions of all mainland states and the Northern Territory. However, there has almost certainly been a historical decline in abundance given the sharp decline in reporting since the 1880s, most likely as a result of predation by non-native mammals. =============================== To unsubscribe from this mailing list, send the message: unsubscribe (in the body of the message, with no Subject line) to: birding-aus-request@vicnet.net.au http://birding-aus.org ===============================
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