Environmental survey findings suggest there are no more platypuses in NSW’s Royal National Park. 

Researchers from UNSW Sydney have confirmed the likely disappearance of platypuses from the Royal National Park, based on results of recent environmental DNA (eDNA).

The eDNA surveys – which use DNA found in water samples to paint a picture of the different animals living in the local environment – found traces of as much as 250 land and water species in the park’s Hacking River and Kangaroo Creek.

Unfortunately - as feared - none of these samples showed signs of local platypus life. But that may soon change with plans to reintroduce platypuses later this year.

“Platypuses once inhabited the rivers of the Royal National Park, but none have been seen there in decades,” says project leader Dr Gilad Bino.

“We’re hoping to change that later this year by reintroducing a founding population of 10 platypuses to the park. Our hope is that they will establish in the area and increase.”

A platypus reintroduction project is being run by researchers from UNSW’s Platypus Conservation Initiative at the Centre for Ecosystem Science (CES), in collaboration with WWF-Australia, Taronga Conservation Society, and NSW National Parks and Wildlife Service.

The conservation project aims to reintroduce platypuses to the Royal National Park as early as August 2022.

“Platypuses are an integral part of eastern Australia’s freshwater environment and belong in the rivers of the park where they once occurred,” says Dr Tahneal Hawke, a scientist on the UNSW team.

The recent environmental surveys - made with support from volunteers of Friends of the Royal - have been the next step in ensuring the sites are suitable and safe for platypus reintroductions.

In addition to confirming platypuses no longer live in the park, the team evaluated the quality of the rivers, surveyed potential platypus food sources, and ensured that potential threats, like sedimentation, pollution, and foxes, wouldn’t threaten new platypus populations.

Based on their findings, the researchers are optimistic the Royal National Park would be able to sustain new platypus populations.

“We found a healthy diversity of animal species during our surveys, including some sensitive species like spiny crayfish, which thrive in clear and flowing water environments,” says Dr Bino.

Professor Richard Kingsford, also on the research team, says: “This is welcome news because it gives us a great chance to restore the rivers in Royal National Park with one of Australia’s iconic species as well as reducing threats to this diverse ecosystem.”