On World Wildlife Day, scientists are celebrating a milestone for eastern quolls: captive-bred animals released into the wild are now breeding, offering hope for a species that has been quietly disappearing from large parts of Tasmania.
When researchers checked on eastern quolls released into Tasmania's midlands last year, they found something that made months of careful planning worthwhile. The females were carrying joeys.
It's the kind of discovery that doesn't happen often in conservation work. Animals bred in captivity and released into the wild face enormous challenges simply surviving, let alone finding mates and reproducing. But at The Quoin, a 5,000-hectare conservation property in the heart of the Midlands, the quolls have done exactly that.
The success is particularly significant because eastern quolls have been vanishing from large areas of Tasmania. Over the past two decades, populations have declined sharply in the Midlands and along the east coast. In some places, these spotted marsupial carnivores have disappeared entirely.
They've already been lost from mainland Australia, where they went extinct more than 50 years ago. Tasmania is their last refuge, which makes understanding and reversing these declines critical.
Eastern quolls are about the size of a small cat, with distinctive white spots scattered across fawn or black fur. They hunt insects and small mammals through the night, playing an important role as predators in Tasmania's ecosystems.
But the reasons behind their decline remain partly mysterious. Feral cats, a changing climate, habitat change and competition with other species all likely play a role, though scientists are still working to understand which factors matter most.
Dr Rowena Hamer, a Research Associate at the University of Tasmania's School of Natural Sciences, has spent years investigating these questions. Her team's approach combines careful field studies with experimental releases, trying to identify what these animals need to survive.
"Seeing females successfully raising pouch young in the wild is a milestone that gives us real cause for optimism," Dr Hamer said.
The breeding success came from animals released in 2025, each fitted with a small tracking transmitter and monitored by a combination of live-trapping and motion-triggered cameras scattered across The Quoin property. The technology has allowed researchers to watch how the quolls adapted to their new environment in remarkable detail.
Cameras recorded where the animals hunted and chose to den. Transmitters revealed their movement patterns and habitat preferences. Field surveys added information about survival and health. Together, these tools helped researchers understand what was working.
What they saw was encouraging. The released quolls learned to find food in unfamiliar territory. They avoided feral cats and other threats. They established home ranges and found safe places to shelter. And crucially, they survived long enough to find mates and breed.
Erin Thomas, a PhD candidate at the University of Tasmania, is working with Dr Hamer to understand how individual traits like genetics and behaviour affect how quolls adapt to new environments.
"We start learning about individual quolls before they're on the ground," Ms Thomas said. "Post release monitoring lets us respond quickly if challenges emerge and helps us understand what's working well."
The challenges these animals faced were substantial. Winter brought the hardest test, when prey became scarce and temperatures dropped. Yet the quolls persisted, and by the time researchers checked on them, females were carrying joeys.
The success at The Quoin is part of a broader effort to secure eastern quolls' future in Tasmania. Researchers plan to conduct more releases at different sites across the state, with each one testing different conditions and approaches. Data from every release helps refine conservation strategies.
The goal is to establish resilient populations that can survive without constant human support. Not isolated groups in fenced sanctuaries, but thriving communities integrated into Tasmania's broader ecosystems, playing their natural role as predators.
Understanding what allowed the quolls at The Quoin to succeed will be crucial for these future efforts. The property offers a mix of open grassland and woodland, providing both hunting grounds and shelter. Feral cat numbers are relatively low. Roads are limited. These factors together seem to have created conditions where quolls can thrive when given the opportunity.
For a species that has been losing ground for two decades, the joeys represent something important. They're evidence that decline isn't inevitable, that with the right conditions and careful management, eastern quolls can make the transition from captivity to thriving in the wild.
The cameras at The Quoin continue to record as the joeys grow. Meanwhile, researchers have been conducting further releases over this summer, gathering more evidence about what it takes to give eastern quolls a future in Tasmania. For now, though, the sight of females with pouch young is reason enough to celebrate.
The project is led by the University of Tasmania in partnership with the Tasmanian Land Conservancy , WWF-Australia , the Invasive Species Council and The Quoin conservation property. Four wildlife sanctuaries provided captive-bred quolls through the Tasmanian Quoll Conservation Program: Bonorong Wildlife Sanctuary, Devils@Cradle , East Coast Natureworld and Trowunna Wildlife Sanctuary .
The work is funded by the Australian Government under the Australian Research Council Linkage Program , the National Environmental Science Program Resilient Landscapes Hub , and Tasmanian Land Conservancy supporters, including a generous contribution from the Elsie Cameron Foundation.
