In 2022 Friends of Royal were approached by Dr Gilad Bino from the University of NSW School of Biological, Earth & Environmental Sciences to determine if we wished to participate in a program to potentially rewild the Royal National Park with platypuses. This dovetailed superbly with FoR’s activities and purpose so of course we said “YES”. Friends of Royal had been seeking a grant to test the waters of the rivers of the Royal and Heathcote National Parks for platypus DNA. But this new project far exceeded that scope.
The testing phase not only tested for platypus DNA (there was none present) but also tested for suitable platypus habitat both in terms of food sources and also river resilience. The good news was that the Hacking and tributaries were indeed found to be suitable for the support of platypuses so the rewilding was possible.
The platypuses to be released into the Royal were taken from two different wild populations to increase genetic diversity: the South coast and Snowy Mountains. Six females and four males were sent to Taronga Zoo for a health check and to be fitted with two different tracking mechanisms: a radio transmitter fitted to the back of each platypus and an acoustic transmitter that was secreted inside.
Acoustic monitoring stations were setup along the Hacking River and Kangaroo Creek, then on two Fridays in May 2023 the platypuses were released into the Hacking River at Wattle Forest. First the six females were sent into the river to find their territories then a week later the four males were released.
Platypus transportation
Platypus release
Platypus free at last
For the first couple of weeks they were tracked using radio receivers as the team walked along the river banks to find the locations that the animals had dispersed to. But the transmissions very quickly stopped being detected, one after another they fell silent. The transmitters on the backs of the animals had all failed, perhaps dislodged.
A released platypus with radio transmitter visible on its back
Volunteers radio tracking platypuses
So it was left for the audio receivers to record the platypus movements which although a reliable method was not real-time recording. Every time one of the animals passed an acoustic receiver the date and time would be recorded, then perhaps once per week a project team member would travel along the river collecting this information from all the receivers.
But the collation of this data told a wonderful story…………after many weeks we could see that all the platypuses that had been released in to the river were still surviving. Some had taken a liking to particular areas of the river and others had been wandering but they were all still alive. Great news.
Platypus sightings started coming in both from volunteers actively looking but also from park visitors who saw them along the river. The sightings were mostly at dawn and dusk but also sometimes later in the morning. Social media came alive with the story.
Then in January 2024 we had some even better news. A young platypus had been sighted near Jersey Springs. This was a real milestone, the rewilded animals were breeding successfully. The research team led by Dr Bino netted near Wattle Forest and Jersey Springs. Some adult platypuses were captured and their health checked. The sought-after juvenile was also caught in the nets, its vital statistics recorded and then it was released without a transmitter.
Dr Bino netting for the introduced platypuses
Checking the nets during the night
Over the next year monitoring of the acoustic receivers continued. As the year wore on a few of the animals stopped being recorded. But in a subsequent netting in January 2025 one of the platypuses which had not been recorded for many months was captured. Its acoustic transmitter was no longer working, probably the battery had failed earlier than expected. This gave substance to the view that all the platypuses were most probably surviving well and the couple that were no longer transmitting had a transmitter issue.
With this information the second phase of the project was launched. Three more platypuses were captured from new locations (ACT, Snowy Valleys region, Southern Highlands). These two females and one male were released south of Waterfall Weir in June 2025. This area had some deep pools where platypuses had been recorded. These animals had acoustic transmitters glued onto their backs. They will be monitored over the next months and years along with the first released platypuses (some of their transmitters are still active).
A further seven platypuses are planned to be rewilded into the Hacking over the next two years.
This rewilding has been a fantastic success: increasing the footprint of these iconic Australian animals across the country and their resilience against future threats. Also providing an opportunity for Sydney residents to observe these unique creatures right on their doorstep.
We will continue monitoring and would like to hear from anyone who observes them in the park. Please let us know by entering the details on the Platypus Observation Form (see below) that we have on our website: