The IBA comprises a small area of Wollogorang Station in the far north-east of the Northern Territory, extending into Queensland. The IBA includes a length of about 50 km of sandstone escarpment and gorges, supporting all recent records of the near threatened Carpentarian Grasswren in the Northern Territory, south of the Carpentaria Highway and east of the Calvert River, extending to Lagoon Creek Gorge in Queensland. This is an isolated area of highly dissected sandstone country, and includes small patches of monsoon vine thickets in sheltered gorges. These are the best developed and richest monsoon rainforest patches in the Gulf Falls and Uplands bioregion, totalling an area of 860 ha but with most individual patches less than 10 ha. The station experiences a monsoonal climate with hot, humid summers and warm, dry winters; mean maximum temperatures range from 29oC in June to 38oC in November and mean annual rainfall is about 960 mm. Recent surveys of other historical sites for Carpentarian Grasswren in the Northern Territory have failed to find this species because of over-burning. If this habitat recovers, or patches of suitable habitat supporting grasswrens are discovered, the IBA could be extended south to China Wall on the edge of Arnhem Plateau. Other adjacent areas of long unburned savanna woodland appear to be important for Gouldian Finches and may justify an extension of the IBA.
There have been a scatter of recent records of the endangered Gouldian Finch (J. Perry in litt. 2008; C. Palmer in litt. 2008) and three breeding pairs found in 2008 when larger hinterland judged to possibly support more than 100 pairs (D. Baker-Gabb in litt. 2008). The near threatened Australian Bustard has been recorded at Wollongorang Station. A number of species restricted to the Australian tropical savanna biome (Varied Lorikeet, Northern Rosella, Silver-crowned Friarbird, White-gaped Honeyeater, Yellow-tinted Honeyeater, Bar-breasted Honeyeater, Banded Honeyeater, Long-tailed Finch and Masked Finch) are suspected to occur in the IBA, but insufficient survey data are available to adequately assess the status of these species.
Non-bird biodiversity: The sandstone ranges of Wollogorang Station support the only surviving population of the critically endangered Carpentarian Rock-rat and a diverse fauna including Rock Ringtail Possum, Short-eared Rock-wallaby, Sandstone Antechinus and Merten's Water Monitor. Merten's Water Monitor is classified as a threatened species in the Northern Territory.
Pressure/threats to key biodiversity
Manage fire to maintain patches of mature spinifex around documented and suspected grasswren sites. Where possible, fire management should be extended into adjacent areas which were formerly suitable for grasswrens. Investigate options for inclusion of significant areas of Wollogorang in the reserve system by agreement with landholder.
Conservation responses/actions for key biodiversity
The Carpentarian Rock-rat recovery plan includes population monitoring of the species and protection of habitat. Key areas for this species are not currently stocked and fire is being managed in these areas under a cooperative management agreement between the Parks and Wildlife Commission of the Northern Territory and the land holder. These actions should help grasswrens in adjacent habitat.
Wollogorang and Wentworth Stations; pastoral leases.
Site access / Land-owner requests
Access is at the discretion of the land-holders.
Justin Perry kindly prepared the map, Alaric Fisher, Carol Palmer and Colin Trainor provided information from their fieldwork visits and Louise Harrison provided background references.
BirdLife International (2022) Important Bird Areas factsheet: Wollogorang. Downloaded from
http://www.birdlife.org on 25/05/2022.