Member Blog: ‘Baritone’ frogs whistle a hopeful tune
East Gippsland’s endangered Watson’s Tree Frog is about to get a lot louder, with 200 froglets and 1,200 tadpoles being released into the wild this season (November 2025 – April 2026).
These small brown frogs, complete with their signature red-striped “leggings”, have been bred through a conservation program at Melbourne Zoo’s Amphibian Bushfire Recovery Centre, where specialist keepers achieved the first successful captive breeding of the species in 2025.
Dr Matt West, Director at Wild Research Pty Ltd, says this release marks a major step forward for the species, more than tripling the number of known sites where Watson’s Tree Frogs are now found in Victoria.
“We’re really worried about the Watson’s Tree Frog,” Dr West said. “The species has declined to the point where we know of just ten sites where it’s holding on, and we’ve only seen breeding at half of those.”
The released frogs have been individually marked, allowing researchers to track their survival and movement in the wild, vital information to guide ongoing recovery efforts.
For a frog that nearly slipped out of sight entirely, its story is still unfolding. Watson’s Tree Frogs were absent from records in Victoria for 19 years before being rediscovered in 2015. Today, they remain under pressure from disease (chytridiomycosis caused by chytrid fungus), introduced species like deer and pigs, and widespread habitat loss following the Black Summer Bushfires, which burned around 90% of their known habitat.
And if you’ve ever heard a tree frog chorus in the bush, you’ll know they don’t hold back.
Watson’s Tree Frogs, along with their close relative the Southern Brown Tree Frog, are known for their distinctive calls. While some species whistle high and sharp, Keeper teams describe Watson’s Tree Frog as the “baritone of the family,” with a deeper, slower call that carries through the night.
“These cute little frogs with their bright red legs really do need our help,” said Dr Mark Norman, Chief Conservation Scientist at Parks Victoria. “Captive breeding efforts by Zoos Victoria have been incredibly important in getting them back into as many places as possible after the impacts of the Black Summer Bushfires.”
The recovery program is a collaboration between Wild Research Pty Ltd, Zoos Victoria, Parks Victoria, the Victorian Government’s Department of Energy, Environment and Climate Action, and the Arthur Rylah Institute, with support from the Victorian Government’s Nature Fund. Melbourne Zoo’s Amphibian Bushfire Recovery Centre was also supported by the Australian Government’s Wildlife and Habitat Bushfire Recovery Program.
