At the time of writing, Rob Brewster, director of Rewilding Australia, was unreachable. He was deep in Booderee National Park on the NSW South Coast, monitoring a small population of eastern quolls that were first released in 2018. There, Rob and his team were happy to find long-term survivors, as well as a new litter of young pups. It’s great news for the program. The spotted, medium-sized marsupials were once found all over south-eastern Australia but now survive only in Tasmania. Rewilding Australia is looking to change that by spearheading the first program to reintroduce the eastern quoll to Australia’s mainland.
It’s not the only program Rob and his team are leading. The organisation is also working with a national network of partners on a proposal to reintroduce another of our missing marsupials, the Tasmanian devil. But why these carnivores? There are many benefits, Rob explains.
Before its disappearance, the eastern quoll was known as the “farmers friend”, beloved by agricultural communities for its appetite for grubs, cockroaches and rats. The Tasmanian devil is known for cleaning up dead animals, which possibly has other benefits, like reducing the potential for flystrike in sheep. As an apex predator in Australia, Tasmanian devils also help regulate populations of other species.
Restoring ecosystems
Rewilding projects like these restore populations of native wildlife. The objectives run deeper than this, though. At its heart, rewilding is about restoring ecosystems and improving the resilience of the Australian landscape.
“We have degraded our landscapes and there is an absence of many mammal species that played a vital role in maintaining the health of our ecosystems. Our plan is to try to reverse that. So rather than just conserve, we want to actually restore our landscape,” Rob says.
This approach to conservation takes a holistic view and understands the importance of native animals in protecting and maintaining the habitat they live in. It recognises links between animals and the environment, a delicate co-existence that has evolved over millions of years, but which has since been tipped off balance by European settlement and introduced species like foxes and cats. Conservationists like Rob believe restoring these populations will have a positive impact on the environment and even improve drought and bushfire resilience in the landscape.
Ecosystem engineers
The removal of keystone species — native animals that maintain stability in the local ecosystem — can be felt across the local ecosystem. The reintroduction of species like the eastern quoll and Tasmanian devil, as well as increasing populations of bandicoots and potoroos, known as the ecosystem engineers, will help its recovery.
“In Australia we have very important keystone species, really the ecosystem engineers, and they’re the small digging mammals that include the bandicoots, the bettongs, the potoroos that are largely absent from our forests these days because of foxes and cats. These are really keystone species that hold ecosystems together,” explains Rob.
To give you an idea of what that means, studies have shown that one bandicoot excavates an average 3.9 tonnes of soil each year. Because we have lost so many of these digging mammals, the result is a build-up of leaf litter and compaction of the soil.
“Because these animals aren’t turning soil over, we now have soil profiles that are difficult for water to penetrate. As a result there is more runoff, you get more erosion and you get less penetration of the soil from rainfall,” says Rob.
Less rain penetration of the soil means less water for the plant species that would usually grow in the area. Over time, the vegetation characteristics of the landscape can change as a result and, in some cases, become even more prone to bushfires.
Rebuilding identity
Every part of an ecosystem, from the animals that inhabit them to the types of plants that grow and in turn support the native wildlife, has a role to play in its local environment. Oliver Costello, CEO of Firesticks Alliance and an expert in Indigenous fire management, says animals are critical in the recovery of the Australian landscape.
“Who they are and carrying out their function is a really important part of that landscape’s identity and its functionality,” he explains.
The impacts of human settlement, invasive species, land clearing, and now climate change have increased the pressures facing our ecosystems. Reintroducing species of plants and animals as part of rewilding efforts is important but needs to be done in the right way. For Oliver, this means staying mindful of what species should be introduced.
“We need to be mindful that it’s done in a way that is actually good for that country. There’s been this big push to replant trees, which is great, but sometimes people plant the wrong trees in the wrong places and that suppresses the potential for that country to actually rebuild its identity,” he explains.
Reintroducing the good fire
As someone leading the revival of cultural burning practices in Australia, Oliver understands how healthy relationships create resilience. For him, this extends to the relationship between the landscape, plant and animal species and fire. “A lot of the landscape looked quite different to how it does today because our Elders were looking after it; they were maintaining their fire management and their resource management, but also following the lore,” he explains.
In the context of environmental conservation, cultural burns are an Indigenous practice that supports and restores ecosystems in Australia. This can be difficult for some people to understand as many of us are more familiar with the Western process of hazard reduction. But cultural burning suggests a different relationship to fire supported by Indigenous knowledge. As Oliver says, “You’re not just burning for fuel. You’re actually burning to promote and sustain healthy species. Fire belongs to country, to the environment, and our ancestors managed these landscapes for thousands of years because they understood that. Because they’d learnt from fire what the negative impacts of fire can be if you don’t maintain good fire regimes,” he adds.
Unfortunately, the decline of good fire regimes in the Australian landscape has impacted our natural ecosystems. It is now more important than ever to understand how good fire can help it heal.
“Being able to implement the right fire is really critical for the resilience of the landscape,” says Oliver. “A lot of plants can handle a little bit of fire, but some can’t handle fire at all. Understanding those sorts of fire relationships, the kinship between fire and different species, and then implementing that is critical.”
Brooke Boland is a freelance writer based on the south coast of NSW.
