SYDNEY, Sept. 8 (Xinhua) -- Australian scientists have successfully made the first-ever release of captively reared mountain frogs into the wild to save the critically endangered species from extinction.
The Red and Yellow Mountain Frogs were successfully reared as part of the Project GRASP (Gondwana Rainforest Amphibian Survival Program) of Australia's Southern Cross University, according to a university statement released Sunday.
The mountain frogs have been returned to a secret location in a remote area of Gondwana Rainforest near the border of the states of New South Wales and Queensland, and released into a predator-free field enclosure in the Tooloom National Park, the statement said.
Researchers collected eggs and adults from the field and have been raising the mountain frogs in captivity since December 2021, which marks the first time the species has been successfully bred and raised in captivity.
The mountain frogs have a very specialized breeding biology, laying a small number of eggs in a burrow where the tadpoles develop from fertilized eggs without a free-swimming tadpole stage, said Project GRASP lead, Associate Professor David Newell.
"The tadpoles feed entirely from the yolk of the egg sack and then metamorphose into baby frogs about 2-3 mm in length. They are incredibly vulnerable. These ones took about four years to reach maturity," Newell said.
The small mountain frog inhabits restricted high-altitude rainforests. Its survival is threatened by climate change, bushfires and the spread of feral pigs, researchers said.
"The ability to establish new populations and supplement existing populations from individuals bred in captivity is a significant milestone for the Mountain Frog," said Australia's Threatened Species Commissioner Fiona Fraser.
The milestone coincided with Australia's National Threatened Species Day on Sunday, which commemorates the 1936 death of the last known Tasmanian tiger, the statement said. ■
