A small, kangaroo-like marsupial, once widespread across the continent, is making a remarkable comeback on mainland South Australia after an absence of more than a century. The brush-tailed bettong, a species driven to local extinction by introduced predators and habitat loss, has been successfully reintroduced to the Yorke Peninsula, where it is now establishing a self-sustaining population despite the presence of feral cats and foxes.
This achievement marks a potential turning point in Australian conservation, demonstrating that with careful management, native species can be returned to landscapes that are not entirely free of their key threats. The project, a large-scale collaboration known as Marna Banggara, is providing a new blueprint for rewilding efforts by showing that coexistence with managed numbers of predators is possible, offering hope for broader ecosystem restoration across the country.
A Lost Engineer’s Return
Once one of the most common small mammals in southern Australia, the brush-tailed bettong, known as yalgiri to the Narungga people, was virtually wiped out from the mainland in the early 20th century. Weighing just 1 to 2 kilograms, these nocturnal animals were easy targets for introduced feral cats and foxes, while widespread land clearing for agriculture removed their natural habitat. The loss of the bettong was a significant blow to the environment. As “ecosystem engineers,” these animals play a crucial role in maintaining landscape health by digging for fungi and tubers. A single bettong can turn over an estimated 2 to 6 tonnes of soil annually, improving water infiltration, cycling nutrients, and helping native plant seeds to germinate. Their disappearance had cascading negative effects on the entire ecosystem.
The Marna Banggara Initiative
The reintroduction is the result of a multi-year effort under the Marna Banggara project, a partnership involving the Narungga Nation Aboriginal Corporation, government agencies, and conservation organizations like WWF-Australia and Zoos SA. The project’s goal is to restore the region’s biodiversity, with the bettong being the first of several species planned for reintroduction. The location, Dhilba Guuranda-Innes National Park on the southern Yorke Peninsula, was chosen for its suitable habitat and the potential for predator management.
A Staged Reintroduction
Between 2021 and 2023, conservationists released nearly 200 bettongs into the park over several phases. The initial translocation in August 2021 involved 40 animals—28 females and 12 males—sourced from a thriving “insurance population” on nearby Wedge Island. This island colony, established in the 1970s from just 11 individuals, has since grown to over 1,500 animals and has been vital for conservation breeding. Later releases introduced bettongs from Western Australia to increase genetic diversity. Many of the released females were found to be carrying pouch young, giving the new population an immediate head start.
Managing an Enduring Threat
Unlike many conservation sanctuaries, the Yorke Peninsula is not a completely fenced, predator-free zone. While a 25-kilometer fence helps limit the influx of predators into the 150,000-hectare safe haven, feral cats and foxes still persist within the landscape. Project partners actively suppress predator numbers through lethal control methods like trapping and shooting. The project’s success in this environment is what makes it so significant; it tests whether a native species can re-establish itself in a more realistic setting where threats are managed but not entirely eliminated. The previous success of a tammar wallaby reintroduction in the park provided confidence that the bettongs could also adapt and thrive.
Signs of a Thriving Population
Monitoring efforts have confirmed that the bettongs are not just surviving but flourishing. Researchers use traps baited with peanut butter to capture and assess the animals, fitting many with radio-tracking collars to follow their progress. The results have surpassed expectations, showing positive trends in population growth and reproduction.
By the Numbers
A monitoring program in late 2024 captured 83 individual bettongs. Of these, 31 were new animals born and raised on the Yorke Peninsula, a clear sign of successful breeding. Furthermore, 22 of the 26 captured females were carrying pouch young, indicating continued reproduction. Encouragingly, researchers found surviving animals from each of the different translocations from both Wedge Island and Western Australia, showing that the founding animals have adapted well to their new home and are actively contributing to the growing population.
Restoring a Wounded Landscape
The return of the brush-tailed bettong is about more than just saving a single species; it is a critical step toward rebuilding a damaged ecosystem. The constant digging and soil turnover performed by the bettongs is already helping to restore natural ecological processes that have been absent for a century. This activity creates better growing conditions for native vegetation, which in turn provides food and shelter for other native animals. The project aims to reintroduce other locally extinct species in the future, including the southern brown bandicoot and western quoll, which will further enhance the biodiversity of the region.
A Collaborative Conservation Model
The success of Marna Banggara is a testament to its collaborative foundation. The project is jointly funded and delivered by a wide range of partners, including the Australian Government’s National Landcare Program, the Northern and Yorke Landscape Board, the South Australian Department for Environment and Water, WWF-Australia, and the Foundation for National Parks & Wildlife. Crucially, it operates in close partnership with the Traditional Custodians, the Narungga people, for whom the return of the yalgiri holds enormous cultural significance. This inclusive approach, combining scientific research with traditional ecological knowledge and broad community support, has been fundamental to its achievements.
Future Outlook and Broader Implications
If the bettong population on the Yorke Peninsula continues to grow and remains stable, it will be documented as the first successful reintroduction of the species to an unfenced mainland area where introduced predators are present. This would provide an invaluable model for conservation projects across Australia, shifting the paradigm from a reliance on expensive, completely protected “arks” to a more integrated approach of managing threats within larger, more complex landscapes. The early victories of the Marna Banggara project signal that with dedication, collaboration, and science-backed strategies, it is possible to rewild parts of Australia and help resilient native species thrive once more.