Zoo-bred eggs might save the Southern Corroboree Frog

Zoo-bred eggs might save the Southern Corroboree Frog

Southern Corroboree Frogs are on the brink of extinction. This year, no wild Corroboree Frog eggs were found during the annual census.Taronga is part of a program to arrest the decline of this vibrantly coloured frog which is dying out due to Chytrid Fungus. The Fungus is a particularly virulent wildlife pathogen which affects multiple species and has caused the extinction of hundreds of frogs worldwide, including six frog species in Australia. We don’t want the Southern Corroboree Frog to become number seven.In past years we have taken Southern Corroboree Frog eggs from the wild and reared them past the vulnerable development stage before returning them back to the wild. We also have an intensive Corroboree Frog breeding program at the Zoo and have released Zoo bred eggs and tadpoles into the wild.This year, along with the Office of Environment and Heritage, we’re trialling some ground breaking techniques, which the frog world is watching with interest to see if it can help save this species from extinction. One of the new techniques has involved building a large enclosure in the wilderness in an attempt to establish a semi-wild breeding population of frogs, living under wild conditions, but excluded from Chytrid Fungus – the disease that’s wiping them out. Essentially we hope we’ve built a disease proof fence, where the frogs can breed and prosper.Last week, we ventured to Kosciusko to release the first 40 Zoo bred eggs into the enclosure and to check on the frogs that we had previously placed in there. Locals tell stories of being able to flip over logs and see the gold and black frogs sitting in abundance on the underside of the wood. We were delighted to be able to do the same and see the frogs we had placed in there a few weeks ago doing so well.This frog breeding season at the Zoo, we’ve managed to breed 1100 Southern Corroboree Frog eggs. This is the our biggest season yet, and vitally required , with no eggs found in the wild this year. In a few weeks time we’ll take these eggs to Kosciusko and place them into special Chytrid disease-free ponds.Hopefully in the future, when the Zoo bred eggs hatch, mature and the frogs reach breeding age, the annual census will look a lot healthier.