We are pleased to announce that a new threatened species, the vulnerable Northern Brushtail Possum, has been added to Mornington Wildlife Sanctuary’s confirmed species list.
This is a significant find for both the sanctuary and the central Kimberley region, where the species has been confirmed only a handful of times, having declined throughout much of its former range.
Braden Riles, North-west Field Ecologist, has provided the following field report.
On 25 May at around 1am, a Northern Brushtail Possum (Trichosurus vulpecula arnhemensis) was detected on a camera trap on southern Mornington.
The trap was deployed on the northern section of the Adcock River, as part of a research project targeting bandicoots in dense sandseep and riparian habitats. The site comprises a thick understorey of riparian grasses and a canopy dominated by melaleuca and eucalyptus trees.
The Northern Brushtail Possum is listed as Vulnerable in Western Australia under the Biodiversity Conservation Act (2016). Woinarski et al. (2014) also considered the taxon met IUCN criteria for Vulnerable, given continuing major declines.
Across northern Australia, Brushtail Possums occupy a range of mostly forested habitat types and are often well-known from residential areas. However, the species has declined from the more arid parts of its range across Australia (Kerle et al. 1992). In the Kimberley, WA, the species is known only from a small number of sites.
Few records exist of the Northern Brushtail Possum throughout the Kimberley, mostly in the Northern and Western Kimberley bioregions. The record from Mornington represents one of only five records from the Central and Southern Kimberley in the last 55 years.
Other recent records from the southern and central Kimberley include a record from Leopold Downs (DBCA; 2018), Karajarri Country in the Southern Kimberley (Karajarri Traditional Lands Association; 2018) and a record from Willinggin Country near Mt Barnett (AWC; 2018).
Known records between 1902 to present from across the Kimberley are shown below:
Question marks indicate a record with no known associated date. These records have been sourced from AWC, Atlas of Living Australia (inc. WA Museum (WAM) & iNaturalist), the WA Department of Biodiversity, Conservation and Attractions (DBCA), Wunaambal Gaambera Aboriginal Corporation (WGAC) and Karajarri Traditional Lands Association (KTLA).
Importance of Record on Mornington
This is a significant sighting on Mornington, representing a new threatened species to be added to the list of species confirmed for the sanctuary. Considering AWC has conducted intensive surveys across Mornington since 2004, this detection is also extremely surprising.
Given that the species has declined from more arid parts of its range (Kerle 1992), records from the central Kimberley are of particular interest. Records such as these may highlight the importance of conducting research and monitoring in more densely vegetated parts of the Mornington landscape (riparian and sandseep habitats), especially following consecutive failed wet seasons, when these habitats are more likely to function as refugia.
AWC’s management has resulted in a greatly reduced incidence of wildfire at Mornington and more broadly across the Ecofire project area; we have also destocked environmentally significant parts of our estate. These actions have improved conservation outcomes for small mammals (Legge et al. 2019).
It is possible that AWC’s management has increased habitat suitability for medium-sized mammals such as the Brushtail Possum, as well as for bandicoots, which also appear to be expanding their range within Mornington.
Kerle JA, Foulke JN, Kimber RG, Papenfus D (1992) The decline of the brushtail possum, Trichosurus vulpecula (Kerr 1798), in arid Australia. The Rangeland Journal 14, 107-127.
Legge S, Smith JG, James A, Tuft KD, Webb T, Woinarski JCZ (2019) Interactions among threats affect conservation management outcomes: Livestock grazing removes the benefits of fire management for small mammals in Australian tropical savannas. Conservation Science and Practice: e52. https://doi.org/10.1111/csp2.52
Woinarski JC, Burbidge A, Harrison P (2014) The Action Plan for Australian Mammals 2012. CSIRO Publishing, Melbourne.