RESEARCH CONFIRMS PLATYPUS ARE LOCALLY EXTINCT IN SYDNEY'S ROYAL NATIONAL PARK

The platypus is just one of our many unique native species at risk of being lost forever.

In partnership with UNSW’s Platypus Conservation Initiative, Taronga Conservation Society and NSW National Parks and Wildlife Services, WWF-Australia is planning to rewild platypus in the park and bolster the health of one of our great and oldest National Parks.

Platypus have not been seen in Sydney’s Royal National Park for decades. This unique egg-laying monotreme is an important ecosystem indicator, meaning their presence, or absence, provides a strong signal for when ecosystems begin to degrade. It’s critical we act now to ensure this iconic native animal is protected and restored to catchments once inhabited by platypus for millennia.

Rob Brewster, WWF-Australia’s Rewilding Program Manager, recently assisted UNSW ecologist and researcher Dr Gilad Bino in surveying the Royal National Park to assess its suitability for platypus reintroduction.

How did you confirm platypus were extinct in Sydney’s Royal National Park?

Dr Gilad Bino: We had hoped we might find DNA fragments of platypus in the water during our surveys, but after checking dozens of sites, unfortunately, we’ve confirmed there were no signs of them in the park. We’ve been filtering through DNA fragments in water samples and looking for the known genome of platypus that would likely be present in the area. We detected more than 200 species - humans, cattle, birds, spiders etc.; but no platypus.

If the platypus disappeared from this area before, how do we know they won’t disappear again?

Rob Brewster: Threats to platypus include drought, pollution from urbanisation, damage to riverbanks and their vegetation, predation and even bushfires. Before bringing platypus back to the park, we need to ensure that threats have been assessed, managed and monitored to determine whether we’re doing enough to rewild our missing fauna.

To do this we’re conducting a range of tests and surveys, including checking water depth and riverbank quality. We’ve also set up sensor cameras across the park. Foxes and cats can threaten many small native mammals, so it’s important we identify the level of activity of these invasive species in this area before reintroducing the platypus. We’re also looking at food abundance in the waterways to ensure there are plenty of aquatic macroinvertebrates for them to eat. 

Dr Gilad Bino: Another important factor is making sure this area can sustain platypus during periods of drought. Platypus are especially vulnerable to drying up of waterways, which increases the risk for predation as they have to travel along dry riverbeds to find pools that still have water. So, we’re mapping the depth profile of the rivers and creeks at potential release sites.

Climate change projections show an increase in the severity of droughts, so it’s crucial we get a good handle on the resilience of platypus and ways we can support native species during extreme weather events.

Rob Brewster: Basically, we need to assess the health of the ecosystem and see if it would be an appropriate area to reintroduce platypus into this region.

And so far, how are things looking?

Rob Brewster: We’re definitely encouraged by what we’re seeing. Healthy invertebrate numbers, low salinity levels and good water and sediment quality; these are all good indicators that this area might once again support platypus. Hopefully, as we continue our work over the next few months, things will continue to go in a positive direction.

Dr Gilad Bino: Our surveys indicate ample resources and habitat. There’s adequate riparian vegetation and lots of big freshwater bugs for the platypus to eat. The riverbank quality is also looking stable enough to support platypus burrows for both shelter and breeding. 

Rob Brewster: Hopefully, we’ll be able to reintroduce platypus in mid autumn 2023, right before breeding season.

Once the environment is deemed suitable, what’s the next step?

Dr Gilad Bino: The next step is to find the right platypus to translocate. We need to make sure we’re not undermining the resilience and the viability of an existing platypus population by moving some here. It’s also essential the first platypus we reintroduce all come from different gene pools to ensure healthy future populations. So, we’re looking at sourcing the founding ten platypus from different areas around NSW. Then, once they’re released into Sydney’s Royal National Park, we’ll monitor them intensively to check on their health and numbers and hopefully see them breeding later in 2023.

Finally, why is it so important to have platypus in the Royal National Park?

Rob Brewster: We can’t just conserve our ecosystems as they are. We need to rebuild them and develop strategies to test how to restore those vital missing links that play a role in maintaining a diverse and healthy ecosystem. So, I’m very excited at the possibility of restoring such a major component of southeast Australia’s ecosystems.

Dr Gilad Bino: We don’t want to be in a situation like our koalas where the seriousness of the situation is swept aside and all of a sudden, the species is facing local extinctions across its range. Platypus are an iconic Australian species, but unfortunately, not many people get to see them in the wild. It’s a very different experience from seeing one at a zoo. My hope is people can have the chance to appreciate native animals in their natural habitat.

Rewilding the platypus is a three-year project dedicated to restoring platypus populations in Sydney’s Royal National Park so that they can thrive across the eastern Australian mainland and Tasmania again. To learn more about our Rewilding program as we work to Regenerate Australia, visit here, or adopt a platypus today to support us in rewilding the platypus.

The platypus is just one of our many unique native species at risk of being lost forever.