White-throated Grasswren (Amytornis woodwardi)
Justification This species has been upgraded to Vulnerable as it is restricted to a small area of occupancy that is severely fragmented and may be declining in area, number of locations and quality of habitat as a result of inappropriate fire management. An associated decline in numbers is probably occurring.
population est 8000
Identification 20-22 cm. Robust, long-tailed, black, white and chestnut ground bird. Black top and sides of head and neck to mantle, with bold white streaks. Chestnut back and rump. Black wings and tail with chestnut edges to feathers. White lores, throat and upper breast. Black gorget on lower breast streaked white. Black sub-moustachial stripe joins breast gorget. Orange-buff belly in male. Sexes similar, but female is darker chestnut, especially on belly and flanks. Juvenile duller, streaking less distinct. Voice Rich, liquid trill. Buzzing contact calls. Hints Hops or scuttles rat-like between rocks and clumps of vegetation.
Range & Population Amytornis woodwardi is endemic to the Northern Territory, Australia. It is found in north-western Arnhem Land, on and around the Arnhem Land escarpment, between Katherine and Maningrida. The small amount of available habitat is severely fragmented and degradation is likely to continue, resulting in a continuing decrease in the number of individuals, currently estimated at c.8,000 within 10 subpopulations. Its area of occupancy is estimated to be 2,000 km.
Ecology It is found on bare, flat plateaux and stepped or terraced hillsides along broad valleys, with or without narrow rocky gullies. Its habitat is characterised by mature spinifex Triodia microstachya, which is used for nesting, and bare rock, with most sites surveyed containing bare pavement and/or boulders.
Threats Although the rocky escarpment habitat offers protection from most fires, the change in the fire regime, to a high frequency of extensive hot fires at the end of the dry season, and the progressive replacement of T. microstachya by annual sorghum, means that this protection may not last