Northern quolls were once a common sight in Australia.

The smallest of the four Australian quoll species, the little nocturnal marsupials with their distinctive white spots, cream bellies and long tails dart across the landscape seeking out insects and small mammals to eat.

But northern quolls are having it pretty tough. So tough in fact, they are now listed as an endangered species by Australia’s Commonwealth Government.

At one time, the northern quoll could be found across northern Australia from south-east Queensland to Western Australia. But introduced species such as the cane toad and feral cat have had a damaging effect on their populations.

It’s important to understand what is happening to this endangered species, which is why Rio Tinto is partnering with organisations to help protect the northern quoll and support an environment where they can thrive.

Environmental adviser Russell Thomas talks about his work with Western Australia’s Department of Parks and Wildlife to protect the northern quoll

Western Australia: Who’s taking the bait?

“I actually saw a quoll my very first day at site,” says Russell Thomas, an environmental adviser in Rio Tinto’s Iron Ore business in Western Australia. “It was living under a donga – the accommodation units for people working at the mine.”

Russell is part of the Yarraloola Partnership team that is working to protect the endangered species.

The Yarraloola Partnership between Western Australia’s Department of Parks and Wildlife and Rio Tinto focuses on the management of introduced predators on the 150,000 hectare Yarraloola Land Management Area (LMA) in the Pilbara.

The Yarraloola LMA is the defined offset area for Rio Tinto’s Yandicoogina Junction South West and Oxbow Iron Ore Expansion Project. A critical part of the offset conditions defined by the Western Australian and Australian governments require that introduced predators are controlled across the Yarraloola LMA.

“Rio Tinto developed a threatened species offset plan which was designed to improve the ecological conditions for the northern quolls,” Russell said.

“We then partnered with the Department of Parks and Wildlife in developing and implementing a landscape-scale aerial baiting programme to target the feral cats.”

A northern quoll in Western Australia A northern quoll in Western Australia
A northern quoll in Western Australia

The programme uses a bait called Eradicat® that has been patented by the department. The bait sausages are made of kangaroo mince, chicken fat and flavour enhancers, but with the addition of toxic sodium fluoroacetate.

The toxin occurs naturally in many native Western Australian plants, so native animals have a high tolerance to sodium fluoroacetate while introduced species like feral cats don’t.

The partnership’s bait uptake study in 2015 showed no evidence that the quolls ate the Eradicat® baits or died as a result of the baiting programme.

It opened the door to the landscape-scale feral cat aerial baiting programme using Eradicat® in 2016. Follow-up research showed the baits had no negative effect on the quoll population, even when the animals came into contact with them.

In fact by studying camera footage captured during the experiment, the team found that after encountering a bait they subsequently avoid the Eradicat® baits.

An additional component of the partnership is the sponsorship of a PhD student from Charles Darwin University to research northern quolls, introduced predators and ecological responses to the programme.

The baiting programme is still in its infancy, but the positive initial results bode well for the northern quoll population. The feral cat control work is scheduled to continue for at least another three years.

Five things to know about northern quolls

Northern quolls are marsupials. They carry their young in a little pouch which develops on the female around their teats soon after mating.

Northern quolls have only one breeding season per year, which begins as early as May.

Northern quolls are nocturnal and shelter in tree hollows, timber piles or rock crevices during the day.

They’re equally at home on the ground or when climbing in trees.

Female northern quolls live for two to three years, only producing one or two litters in their lifetime. Their male counterparts die soon after mating, rarely living for more than one year.

Queensland: A rare discovery

On the other side of the country are the Weipa bauxite operations, in far north Queensland. It’s where Rio Tinto’s Chris MacColl works, who thinks he may have one of the best jobs going. As the site’s threatened species research officer, he’s involved in specialist work to monitor and protect threatened species that are found on the mining lease area.

In 2013, Rio Tinto employees found 24 northern quolls in an area of the mining lease north of the Embley River.

“As part of our regular baseline ecological surveys, a member of the team managed to catch a quoll,” said Chris.

“It was actually really exciting for the team at the time and it helped develop the environmental management plan for the area. It meant that mining was excluded from that part of the lease.”

It was an important discovery because most of the northern quolls in the area had been wiped out by poisonous cane toads and feral cats.

Since the find, annual monitoring of the population has been undertaken using motion sensor cameras. The team has also conducted tracking studies to follow the movements of individual quolls wearing radio emitting collars. Both programs have provided valuable insights into northern quoll ecology and how we might manage these populations.

Rio Tinto’s Weipa team and Nanum Wungthim Land and Sea Rangers undertake monitoring and survey work in Queensland Rio Tinto’s Weipa team and Nanum Wungthim Land and Sea Rangers undertake monitoring and survey work in Queensland
Rio Tinto’s Weipa team and Nanum Wungthim Land and Sea Rangers undertake monitoring and survey work in Queensland

The discovery is one of only three known quoll populations left on Cape York Peninsula, with another population discovered just 20 kilometres outside Weipa on the Napranum Deed of Grant in Trust (DOGIT) land that neighbours the mining lease. The Napranum DOGIT is governed by the Napranum Aboriginal Shire Council.

So the Rio Tinto team reached out to the Nanum Wungthim Land and Sea Rangers for an opportunity to work together to learn more about the northern quoll populations in the area.

The rangers care for the Napranum DOGIT land on behalf of the shire council, undertaking regular patrols throughout the area, recording and monitoring information about the country.

Together Rio Tinto people, ecologists and the rangers completed quoll surveys on the mining lease, Napranum DOGIT land and neighbouring properties.

Chris said the collaborative partnership started around 18 months ago, and is expected to be ongoing.

“At the end of the day, we’re all trying to do the same thing – protect species like the quoll,” he said.

“So we need to work with our neighbours to develop a collaborative strategy to help manage the northern quoll population.”

The Weipa team and rangers will undertake additional surveys over the next 12 months to expand our knowledge on northern quolls.