The ACT Government is reintroducing the eastern bettong, a small marsupial related to kangaroos, that has been extinct from mainland Australia for nearly 100 years.
In 2011, a number of adult bettongs were brought from Tasmania, the only place where they are now found in the wild, to form a captive breeding colony (a founder population) at Tidbinbilla Nature Reserve.
In late May 2012, another 24 bettongs were bought from Tasmania. Some were added to the breeding colony at Tidbinbilla while the rest were taken to the box-gum woodlands of Mulligans Flat Woodland Sanctuary in the first ‘wild-to-wild’ bettong translocation.
The Mulligans Flat bettongs have been fitted with radio collars so researchers can track their movements, monitor the population and see how they are contributing to the restoration of the sanctuary’s woodlands.
Media release: Bettongs jump at the challenge to restore woodlands (1 June 2012)
View the video 'Return of the Bettong' to find out more about the Eastern Bettong Project and to see footage of some of the first bettongs to be reintroduced
The eastern bettong (Bettongia gaimardi) is also called the Tasmanian bettong. It is a woodland-dwelling, rabbit-sized kangaroo. An unusual characteristic of eastern bettongs is their ability to carry nesting material with their tail.
Bettongs build densely woven nests of dry grasses and bark under fallen timber or among small bushes and tussocks. By night, they roam widely in search of food – underground fungi (commonly referred to as truffles) and the tubers of lilies, orchids and other plants.
Bettongs were once common throughout the south-eastern seaboard including the ACT, but became extinct on the Australian mainland due to foxes, land clearing, livestock grazing and the invasion of rabbits. Until recently, they were found only in Tasmania.
Returning a local species that has been missing for such a long time is an important step in restoring the ACT’s grassy box-gum woodlands to a condition that more closely represents how they were prior to European settlement.
Bettongs are considered to be ‘ecosystem engineers’. This means they have an important ecological role that benefits a range of other woodland species. Their foraging activities create up to 3000 diggings per hectare, which has positive effects on the soil, water and nutrients. The extensive diggings of bettongs contribute to ecosystem health by increasing the soil’s capacity to capture and absorb water. Bettongs also disperse the spores of the fungi on which they feed. These fungi enable plants, such as eucalyptus and acacia trees, to extract nutrients from the soil.
The reintroduction of bettongs will support research on woodland restoration and increase our knowledge about their role in ecosystem function and the best ways to re-establish populations in former habitat.
Bringing the bettong back to the ACT will also provide insurance for the populations in Tasmania, where the recent introduction of the European red fox poses a significant risk to the species.
In 2011, 23 bettongs were brought to Tidbinbilla Nature Reserve to establish a captive breeding or founder colony. Individuals from that colony have produced many pouch young and the population at Tidbinbilla has increased.
The first of the Tidbinbilla bettongs were released into Mulligans Flat Woodland Sanctuary in autumn 2012, establishing a second ACT bettong colony. In late May 2012, another 24 bettongs were captured from different sites in Tasmania and brought to the ACT. They were divided between the Mulligans Flat Woodland Sanctuary and the Tidbinbilla breeding colony.
The aim is to have approximately 30 founder animals at both Tidbinbilla and Mulligans Flat by the end of 2012.
The bettongs have been sourced from various locations in Tasmania to ensure that the ACT populations are genetically diverse, which increases their chances of survival and production of healthy offspring.
The bettong reintroduction project is an important part of the Mulligans–Goorooyarroo Woodland Restoration Experiment, a research program led by the ANU in partnership with the CSIRO and the ACT Government.
The Mulligans Flat Woodland Sanctuary encloses over 400 hectares of critically endangered yellow box-red gum grassy woodland. The aim of the sanctuary is to restore the woodlands to pre-European condition by removing feral animals including foxes, cats, hares and rabbits and reintroducing locally extinct species. It is the only such sanctuary for this type of ecosystem. The bettong will play a special role through improving the ecology and health of the box-gum woodlands in the sanctuary.
To date, the involvement of leading research institutions – the Australian National University and the CSIRO – has led to the investigation of a number of management ‘treatments’ in the Mulligans Flat–Goorooyaroo woodland reserves, such as burning, exclusion of kangaroo grazing and the introduction of dead wood on the ground layer to improve the condition of the box-gum woodland for biodiversity. This research project will also involve a scientific investigation of bettong ecology within a well designed experimental framework.
The ACT Government has played a pivotal role in providing scientific support from ESDD and land management support from TAMS.
More information about the research project and the Mulligans Flat Woodland Sanctuary can be found at:
Key habitat requirements for the bettong are open woodland with sufficient ground cover to build nests, as well as sufficient food, particularly underground fungi. Mulligans Flat Woodland Sanctuary has similar habitat to that favoured by Tasmanian bettongs.
With the predator proof fence, the Mulligans Flat Woodland Sanctuary is highly suitable for a new colony of bettongs in the ACT.
The Tasmanian Government Department of Primary Industry, Parks, Water and the Environment (DPIPWE) provided invaluable support for ACT field parties in Tasmania.
A sedation trial was carried out in Tasmania to evaluate an appropriate tranquilliser dose for bettongs so they could be safely sedated to reduce stress during transportation. Special crates were fitted out to comply with air transport regulations and meet the needs of eastern bettongs to ensure they arrived safely.
A translocation trial including trapping, road transport and airfreight from Tasmania to the ACT was then completed with four bettongs (one pregnant, one with pouch young, one aged female and one male) to test all procedures from trapping, through to handling, air freight, health checks on arrival at Tidbinbilla, and quarantine.
A field survey was carried out in Tasmania to find sites within each genetic region where bettongs were relatively abundant, so the required number could be obtained without harming the local population. The sites are outside the conservation reserve system, mostly in eucalypt plantations and forestry areas.
The project has included the Territory and Municipal Services Directorate (especially Parks and Conservation Service), Environment and Sustainable Development Directorate (especially Conservation Planning and Research), Mulligans Flat Woodland Sanctuary Board of Management the Tasmanian Department of Primary Industry, Parks, Water and the Environment (DPIPWE), Australian National University Fenner School of Environment and Society, CSIRO, and James Hutton Institute in Scotland.