Brolgas are listed as endangered in Victoria because drying wetlands threaten their habitat. The state now holds only about a thousand individuals, far fewer than in northern Australia where numbers remain stable.

A new study by Macquarie University found that genetic variation among Victorian brolgas has declined and become distinct from northern populations. The researchers examined DNA samples from birds across the region.

The study also showed little genetic variation among individual Victorian birds, increasing future vulnerability. With fewer unique genetic traits, the population has less capacity to adapt to new challenges.

"Reduced wetland habitat is driving the loss of numbers and genetic diversity," said lead researcher Abby Bryce. She warned that fewer birds and less genetic diversity mean the population loses the rare individuals that could give it an edge in extreme events.

Encouragingly, wetland restoration projects such as Green Swamp in the Southern Grampians and Tae Rak (Lake Condah) have attracted brolgas back. Both sites now host flocks of the birds, offering a hopeful sign for the species’ recovery.