27 June 2023

REWILDING THE EASTERN QUOLL

Eastern quolls are one of four species of quoll in Australia. But while northern, spotted and western quolls can still be found on our mainland, the last sighting of a wild eastern quoll was in Sydney’s Nielsen Park in 1963. These furry, cat-sized marsupials are sadly on the IUCN Red List of species Endangered with extinction, and WWF-Australia wants that to change.

A population in decline

There are a few theories about why eastern quolls disappeared from the mainland, including a potential epidemic in the 1900s. But the most compelling is that their population decline occurred when the fox population was increasing rapidly in southeastern Australia. Foxes are a known predator of eastern quolls, along with dogs and feral cats.

Two eastern quoll joeys at Trowunna Wildlife Park, Tasmania
Juvenile eastern quolls, Mole Creek, Tasmania, 2017 © WWF-Aus / Madeleine Smitham

Tasmania is fox free and was once considered to be the last stronghold for eastern quolls. But worryingly, over the last 20 years, populations there have been rapidly declining, due to threats from agriculture, feral cats, climate change and people. There’s reason to be concerned about this. As eastern quolls are carnivores, they regulate Tasmania’s ecosystem by eating small rodents, birds, and insects like beetles, cockroaches, grubs and spiders. It’s a significant role – one WWF-Australia is determined to restore to the mainland.

Reintroducing the eastern quoll to Booderee National Park

WWF-Australia first thought to reintroduce a test group of eastern quolls to the mainland in 2014 but knew the right location was key to their long-term survival. 200 years ago, Sydney Harbour was a thriving habitat for eastern quolls, and present-day Booderee National Park in Jervis Bay shares some important environmental similarities. It’s a peninsula, with open woodland, grasslands and rainforest gullies. Eastern quolls were found in the Shoalhaven region of NSW south coast possibly as recently as the 1960s, and the park has an extensive fox monitoring and management program – all strong indications it could provide a habitat for quolls to persist.

Together with Australian National University, Parks Australia, Taronga Conservation Society and the Wreck Bay Aboriginal Community, we created a translocation plan, and in 2018, with help from the Tasmanian Quoll Conservation breeding program, 20 males and females who were bred in wildlife sanctuaries were reintroduced into the park and tracked with GPS collars. Initially, the quolls were active in the daytime and lacked the hunting and scavenging skills of wild quolls, but this quickly changed. In a little over a month, they became nocturnal learning to hunt, scavenge and find shelter. Some even learned to evade predators.

Eastern quoll in Booderee National Park after being released.
Eastern quoll in Booderee National Park after being released. © WWF-Aus / Morgan Cardiff

Risks, threats and learnings

A lot was learned from this first reintroduction. With many new survival skills for the quolls to master, almost 80% were sadly lost in the first few months. The team continued to monitor the remainder and was encouraged to see that those who adapted and learnt the necessary skills for survival in the wild went on to prosper in the park.

Initially, the team thought this small success could be down to numbers. So, in 2019, 40 more quolls were reintroduced to the park. Although there were some similar results, with losses from road accidents, domestic dogs, foxes and pythons, there were early signs of hope as quolls from the first year were also observed breeding with the second. Having been through such adversity, it was incredible to see the first litter of eastern quolls born on mainland Australia in decades. However, with the population so perilously small and juvenile mortality naturally high, they sadly couldn’t survive in the long-term, and the last sighting of an eastern quoll on camera in Booderee Park was in January 2021.

The future of the rewilding project

A lot was learned from these two reintroductions and working with our partners, changes were made to give new eastern quolls who will return to the mainland the best possible chance. What’s planned is a predator-proof sanctuary, with a fence specifically designed to limit impact on local wildlife. Each side of the fence is less than 1,000 metres long, so large animals like swamp wallabies and eastern grey kangaroos can go around it. The fence has also been designed so they can’t jump over it and prevents them becoming entangled.

This haven will keep the quolls safe in a semi-wild environment where they can learn skills for the long-term. They can then be reintroduced into environments outside of the fence when they’ll have the highest chance of survival. Juvenile quolls born in the wild can also be moved there until they reach maturity in a strategy called ‘headstarting’, which has yet to be tested in a quoll reintroduction. This fenced area will provide a source population that can annually contribute to the population of eastern quolls outside the fence that will eventually be established in the park.

Hope for the future

Eastern quolls once lived and thrived on mainland Australia for hundreds and thousands of years. They have evolved alongside everything in the landscapes they once roamed and provide a vital role in our ecosystem. By working to innovate, learn and adapt our science-based approaches and through sharing knowledge and resources with our partners, we hope to restore this iconic carnivore to where it once roamed.

An eastern quoll is released on mainland Australia in March 2018 – the first wild reintroduction attempt for the species since its mainland demise over half a century ago
An eastern quoll is released on mainland Australia in March 2018 © Dr Judy Dunlop / WWF-Australia

Beyond Booderee National Park, WWF-Australia is also working with NSW National Parks and Wildlife Service, with the aim of providing over 5,000 hectares of feral-free fenced landscape for eastern quolls. And we’re also working in Tasmania with the University of Tasmania and Tasmanian Land Conservancy to test experimental reintroductions using eastern quolls raised through breeding programs, to reverse the declines in quoll populations, and to restore locally-extinct populations. We’ve begun the journey to achieve our three broad eastern quoll goals - to downlist the eastern quoll from its Endangered status, to restore eastern quoll populations in Tasmania, and to rewild the species to mainland Australia’s east coast.

There’s a long road ahead, but WWF-Australia is determined to get there. With your support, we can build and maintain this safe haven for eastern quolls. It’s a first vital step to re-establishing them in the wild and reversing their mainland extinction.

Eastern quolls have a fighting chance of survival on the mainland. But we can’t do it without your help. Be part of their journey by donating to WWF-Australia today and help restore them to their rightful place in Australia’s ecosystem.

* Rewilding Booderee is a collaboration between National Parks Conservation Trust, Parks Australia, the Australian National University and WWF-Australia, with support from Shoalhaven City Council, Foundation for Australia’s Most Endangered Species and Wreck Bay Aboriginal Community Council.