The discovery of a juvenile platypus has researchers heralding the success of a program that reintroduced the monotremes into a national park where they have been extinct for decades.
Ten platypuses were reintroduced into the Royal National Park, south of Sydney, in May and a six-month-old juvenile was recently discovered when researchers returned to check on the fledgling population.
The juvenile platypus was said to be in "excellent condition", weighing about 850g.
She was fitted with a microchip before being returned to the national park's waterways, which are also being extensively monitored.
Samples have been taken to confirm which of the reintroduced platypuses produced the offspring.
Ongoing monitoring and tracking of the native animals indicates they are all still alive and active.
"Not only are they surviving, but the discovery of a juvenile platypus shows they are thriving, which means the Royal National Park is in great shape," Environment Minister Penny Sharpe said on Thursday.
The relocation program demonstrated the possibility of bringing animals back from the brink of extinction and the knowledge gained will be applied across the state, Ms Sharpe said.
The 10 platypuses were captured from around NSW to ensure genetic diversity and were taken to a purpose-built platypus facility at Taronga Zoo.
There they were fitted with trackers and reintroduced to the national park, where they had been locally extinct for more than five decades.
University of NSW conservation scientist Gilad Bino said the reintroduced platypuses were adapting well to their new environment.
"The success of this reintroduction underscores the vital role that targeted conservation actions, such as translocations, rescues and reintroductions, play in the preservation of the platypus across its range," he said.
Platypuses, along with fellow Australian-native echidnas, are the only known egg-laying mammals.
