Cane toad sausage might save the Northern Quoll from extinction Dr Jonathan Webb

Pictured: Researcher Dr Jonathan Webb

Saving the Northern Quoll

Like many of Australia’s small marsupial mammals, the Northern Quoll is under serious threat of extinction from habitat destruction, feral cats and changing fire management. However, it is the lethally poisonous cane toad, which jumped across Kakadu National Park boundaries in 2001, that has decimated quoll numbers.

“Quolls have no physiological resistance to toad toxin and die after [trying to eat] large toads. In many parts of the Top End quolls have disappeared completely since the arrival of cane toads."

“Quolls have no physiological resistance to toad toxin and die after [trying to eat] large toads,” says wildlife ecologist Dr Jonathan Webb, a senior lecturer at UTS’s School of Life Sciences. “In many parts of the Top End quolls have disappeared completely since the arrival of cane toads."

Dr Webb is working with a range of researchers and industry partners including Kakadu National Park, the Australian Wildlife Conservancy, the Northern Territory Department of Land and Resource Management and Territory Wildlife Park, on a novel solution to stop quolls from consuming toxic cane toads.

In 2009, Dr Webb developed a cane toad sausage that consisted of a non-lethal toad paired with a nausea-inducing chemical. After eating the bait, the quolls in the experiment would then associate the smell and taste of cane toads with illness and refuse to eat them, thus becoming “toad-smart”.

It is hoped that toad-smart quolls will be able to survive reintroduction into the wild and repopulate Kakadu National Park.

"A PhD student will help Territory Wildlife Park reintroduce toad-smart quolls to Kakadu, and Indigenous rangers from Kakadu National Park will help monitor the quoll population and will manage additional threats," Dr Webb says.

The second part of the project involves training wild quolls to avoid cane toads prior to the toads invading the east Kimberley.

Dr Jonathan Webb with a quollNow that Dr Webb and his team know that wild quolls will consume the cane toad sausages, the baits will be fed to quolls in the east Kimberley before the cane toad invasion.

"Australian Wildlife Conservancy will survey quoll populations before toads invade and will coordinate baiting prior to toad invasion," Dr Webb says. "A PhD student will monitor quolls via radio-telemetry at control and baited sites, before and after toad invasion."

If the team can train enough wild quolls to avoid eating cane toads, they may be able to prevent the local extinction of the northern quoll.

"Rather than trying to eradicate an invasive species, we're using conditioned taste aversion to modify the behaviour of the predator."

In April 2016, ten “toad smart” quolls were released to Kakadu with plans for more quolls to be released later in the year.

Story: Casey Leneve and Marea Martlew
Image: Dr Jonathan Webb