Bilby boom: australian recovery story rewrites the century-long narrative

A decades-long absence is being erased in the Mallee Cliffs National Park. The greater bilby, once teetering on the brink of local extinction, is experiencing a population explosion, reaching nearly 2,000 individuals – a remarkable turnaround from a mere 50 ‘founder’ bilbies released in 2019.

A fenced sanctuary, a second chance

The project, a collaborative effort between the Australian Wildlife Conservancy (AWC) and the New South Wales government, established a fenced breeding area to shield the vulnerable marsupials from predators like feral cats and foxes. This exclusion, Rachel Ladd, an AWC wildlife ecologist explains, “really allows them to do well and breed up in numbers and persist in the environment.” The initial release of 50 bilbies, including a contingent from Thistle Island off the coast of South Australia, marked the first attempt to re-establish a wild population in the region for over a century.

Between 2021 and 2023, the team strategically introduced 107 bilbies from the breeding area into a secure 9,570-hectare habitat within the park. Recent surveys reveal a total population estimated at 1,840 – a figure that underscores the project’s surprising success. Motion-sensor cameras capture the Animals dispersed throughout the protected area, diligently digging burrows and reshaping the landscape.

But the Mallee Cliffs success isn’t an isolated case. The AWC’s annual bilby census across its six large predator-free areas—spanning New South Wales, South Australia, Western Australia, and the Northern Territory—shows an even more dramatic overall increase. The total bilby population has surged from an estimated 3,300 in 2025 to a staggering 5,300 in 2026 – a more than fourfold increase compared to 2021.

Ecosystem engineers: reshaping the landscape

The bilby’s role extends beyond its mere presence; it’s an “ecosystem engineer,” as Tim Henderson, another AWC ecologist, puts it. At the Newhaven Wildlife Sanctuary in the Northern Territory, for example, the rapid population growth—from 66 founder bilbies just three-and-a-half years ago to an estimated 530—is actively transforming the environment. “Their digging turns over large amounts of soil, helping retain rainfall and promote new vegetation growth,” Henderson noted, highlighting the bilbies’ indirect contribution to habitat restoration.

The boom-and-bust nature of arid environments inevitably influences bilby populations. As Ladd explains,