Common name: northern bettong
Scientific name: Bettongia tropica (bettong = Aboriginal word for small wallaby, tropica = occurs in the tropics)
Family: Potoroidae (Potoroos and bettongs)
Conservation status: This species is listed as Endangered in Queensland (Nature Conservation Act 1992) and nationally (Environment Protection and Biodiversity Conservation Act 1999). It is ranked as a critical priority under the department's Back on Track species prioritisation framework.
Description: The northern bettong is a delicately-built rat-kangaroo about the size of a rabbit with a body length between 300-380 mm and a tail length of 290-360 mm. An adult weighs between 1-1.5 kg. It has pale grey fur and a cream-coloured belly. A short black brush of fur on top of the tail tip distinguishes it from the rufous bettong Aepyprymnus rufescens. The tail is prehensile (capable of grasping) and is used to carry nesting material. The northern bettong has a broad head with a flattened, naked nose and short, pointy ears.
Habitat and distribution
The northern bettong is endemic to the Wet Tropics bioregion in north Queensland. It has a small, fragmented distribution, occurring in upland grassy eucalypt woodland and tall open forest along the western edge of the bioregion. Northern bettong populations are fragmented from the Mt Windsor Tableland (45 km NW of Mossman) in the north to Coane Range (65 km S of Ingham) in the south, representing a range of around 275 km. However, surveys in the last several years have failed to detect the species at Mt Windsor and the Coane Range, indicating a decline in these populations. The Lamb Range (25 km SE of Mareeba) is the only known stronghold for the species, with a large population over a relatively broad area. Recent surveys have shown northern bettongs are persisting at the Carbine Tableland, although the status of this population is relatively unknown.
Life history and behaviour
Truffles (fruiting bodies of underground fungi) and cockatoo grass Alloteropsis semialata appear to be the most important components of the northern bettong’s diet. It also feeds on a wide range of foods including roots, tubers, seeds, insects, grass and leaves.
They are solitary animals that have three or four nest sites which they use randomly. They are believed to become sexually mature at five or six months of age and can breed at any time of the year, producing two to three litters of a single young. The gestation period is about 21 days and pouch life 110-115 days. Northern bettongs live for approximately six years.
Several threats are believed to affect the survival of northern bettongs. These threats continue to affect existing populations, compromising their persistence and limiting the likelihood of populations recovering to their former status. In order of perceived significance these are:
- changes to fire management which alter the preferred northern bettong habitat from open to closed forests
- feral pigs through competition for truffles and alteration of their habitat
- feral predators especially cats and foxes
- cattle grazing which alters to structure and composition of the understorey
- habitat clearing for agriculture, forestry and residential activities
- climate change leading to habitat alteration.
Guidelines for managing fire in northern bettong habitat
Improved fire management was identified by the Northern Bettong Recovery Group as a key action necessary to recover northern bettong populations. In 2016-17, the Guidelines for managing fire in northern bettong (Bettongia tropica) habitat were developed to provide species specific best practice guidelines for land managers. A Field guide for managing fire in northern bettong habitat was subsequently produced providing a practical summary supplemented with photos. These guidelines provide assistance to rangers and other land managers for on-ground burn planning and implementation, specific to the objectives of improving and maintaining northern bettong habitat.
The main objectives outlined in the Recovery plan for the northern bettong (Bettongia tropica) 2000-2004 include:
- Maintaining and improving habitat for the northern bettong, particularly via suitable fire management practices.
- Improving our understanding of ecological factors such as interactions with introduced predators and herbivores (e.g. cattle)
- Improving our understanding of species biology including genetics and disease research.
- Monitoring population trends across the species range, particularly the main population on the Lamb Range.
Curtis, LK, Dennis, AJ, McDonald, KR, Kyne, PM and Debus, SJS (eds) 2012, Queensland’s Threatened Animals, CSIRO Publishing, Collingwood.
Department of Environment and Heritage Protection 2017, Guidelines for managing fire in northern bettong (Bettongia tropica) habitat , Department of Environment and Heritage, Brisbane.
Department of Environment and Heritage Protection 2017, Field guide for managing fire in northern bettong habitat (A5), Department of Environment and Heritage, Brisbane.
Dennis, AJ 2001, Recovery plan for the northern bettong, Bettongia tropica 2000-2004, Report to Environment Australia, Canberra. Queensland Parks and Wildlife Service, Brisbane.
Johnson, CN and McIllwee, AP 1997, Ecology of the Northern Bettong Bettongia tropica, a Tropical Mycophagist, Wildlife Research 24, 549-559.
Johnson, PM 2003, Kangaroos of Queensland, Queensland Museum, Brisbane.
Winter, JW and Johnson, PM 2002, Northern bettong, in Strahan, R. (ed.), The Mammals of Australia, revised edition, Reed New Holland, Sydney.
WWF-Australia 2018, ‘Bettongia tropica Population Status, Distribution, Habitat Use and Impact of Fire’, Final Report prepared by WWF-Australia, Sydney.