Quoll refuge in the Kimberley

As Uunguu Rangers work to achieve the targets of their healthy country plan, they are also helping to maintain and improve habitat in one of Australia’s most important refuges, to the benefit of many animals.

From the air, Pariaba rests on the edge of the Timor Sea like a gnarled hand, the boney cap of its laterite plateau fringed with gullies of monsoon rainforest that fall down to the ocean.

A wire fence runs across the narrow stretch of land, incised on both east and west by mangrove-fringed creeks, where the wrist of the peninsula joins the coast.

No feral cattle roam here. The peninsula is naturally protected from wildfires, and feral cats are rarely seen.

Species that are critically endangered across the border in the Northern Territory, such as the Golden-backed Tree-rat (Mesembriomys macrurus) and Pale Field Rat (Rattus tunneyi), are abundant on Pariaba, as is the endangered Northern Quoll (Dasyurus hallucatus).

Largely free from fire, cats and cattle, Pariaba is a refuge for the small mammals that are fast declining across much of Australia’s north.

The Bougainville Peninsula, as it is known in English, is part of the Uunguu (living home) of the Wunambal and Gaambera peoples of the Kimberley region.

For the past ten years, Wunambal Gaambera Aboriginal Corporation’s Uunguu Rangers have been working to keep their country healthy and protect all species within the Uunguu Indigenous Protected Area.

Bush Heritage’s long-standing partnership with Wunambal Gaambera began in 2008 with the drafting of the Wunambal Gaambera Healthy Country Plan 2010–2020, and we continue to support the plan’s implementation.

The plan includes targets around improving the health of apex animals such as aamba (kangaroos and wallabies) and jebarra (emu), wulo (rainforest) and rock art, and the implementation of right-way fire. In the process of working towards those targets,

Uunguu Rangers are also having a much broader impact; when Wunambal Gaambera people see big animals on country, they know it is healthy and they see it as a sign that smaller animals are thriving, too.

One of the most effective tools Uunguu Rangers deploy to protect habitat is right-way fire. Through this program, rangers have been working to end the cycle of late season wildfires. Right-way fire uses a `two-way' approach that blends traditional fire knowledge with modern technologies such as satellite mapping and aerial incendiary devices.

The decline of the traditional fire practices of Aboriginal Australians has seen early dry season fires replaced by intense, late season wildfires that burn over hundreds of thousands of hectares.

Mammals have little chance of escaping from these fast-burning wildfires. If they do manage to evade the flames, fires of that intensity can completely devastate habitat.

The fires lit by Uunguu Rangers in the early dry season are cooler, slower fires that burn over smaller areas. Right-way fire, as a primary 'healthy country tool', helps improve and maintain habitat for aamba and jebarra.

“Burning the right way is important for making sure there is enough food for aamba to grow healthy,” says Neil Waina, Uunguu Head Ranger. “Since we started our burning program we have noticed more animals like kangaroos and emus coming back.”

Right-way fire also benefits other species such as quolls (wijingarri in Wunambal language or bangajii in Gaambera language); smaller and cooler fires help create a mosaic of burnt and unburnt vegetation, which results in different food plants and habitats.

“When we go out bush, we see the big animals like kangaroos and emus. If they are healthy then we know the country is healthy. We see the smaller animals in the camera traps, so we know we are burning country the right way,” says Neil.

The Cane Toads cometh

Cane Toads arrived in earnest on Wunambal Gaambera country in the 2018 wet season, making it as far west as the Mitchell Plateau. While they’re a threat to the survival of many small mammals, Northern Quolls are particularly at risk; the quolls’ size (the largest males weigh just over a kilogram) and ferociousness means they are capable of attacking adult Cane Toads and ingesting a lethal dose of toxin.

As Cane Toads advanced across the Northern Territory, Northern Quoll populations immediately collapsed, and scientists are deeply concerned that Kimberley quolls face a similar fate.

In rugged and remote areas with limited road access it’s difficult to manage threats such as Cane Toads, says Tom Vigilante, Wunambal Gaambera Aboriginal Corporation's Healthy Country Manager – a Bush Heritage-funded role.

Uunguu Rangers, as part of healthy country operations, are assisting scientists from Western Australia’s Department of Biodiversity, Conservation and Attractions to test whether Northern Quolls can be trained to avoid Cane Toads.

Cane Toad ‘sausages’ made from toad flesh and laced with a chemical that induces nausea are dropped from helicopters into Northern Quoll habitat. The idea is that any Northern Quoll that eats a sausage will develop a negative association to the smell of Cane Toads and avoid them.

It’s a method that shows promise but is not without technical difficulties: the sausages need to be dropped from the air in the afternoon so they land fresh, but are not eaten by ants before the quolls emerge from their dens at dusk. And, of course, the quolls need to find them.

“It’s not a silver bullet,” says Tom, “but it might help increase survival a little.”