A so-called "zombie fish" thought to have been extinct for two decades has been released into a Victorian wetland after it was brought back from the dead.
The native southern purple-spotted gudgeon was declared extinct in Victoria in 1998, before two were discovered near Kerang in the state's north in 2019.
The North Central Catchment Management Authority resolved to get the freshwater fish, dubbed "zombie fish", thriving again after the find.
A program to breed an "insurance" population of the endangered fish, in partnership with Melbourne's SEA LIFE aquarium, was declared a success after the first eggs hatched on New Year's Day.
Nine months on, breeders released the fish into McLartys Lagoon, a natural wetland on the mid-Goulburn River in Victoria.
The fish are small and purplish-brown to yellowish-brown, with a rounded head and a small mouth.
"Now that the (young) have developed to around 2cm to 3cm long, we have returned them into pest-free ‘surrogate’ sites in the wild to expand the population,” aquarium curatorial supervisor Samuel Fawke said.
It is the first time SEA LIFE Melbourne has bred and released native fish into the wild.
Other populations of the zombie fish have been released in different wetlands in Victoria.
Southern purple-spotted gudgeon fry are about 15mm in size, although they can reach 12cm.
They feed off live and pre-made foods and like to live in dense reeds.
The aquarium worked with the Goulburn Broken Catchment Management Authority and the North Central authority for the release, which happened ahead of National Threatened Species Day on Thursday.
Visitors and locals to Melbourne can see the southern purple-spotted gudgeon at the SEA LIFE aquarium.