SCIENTISTS say they have found a new way of protecting Australia's wildlife from feral cats.
Using polymer chemistry principles, researchers at University of South Australia's Applied Chemistry and Translational Biomaterials Group have created Population Protecting Implants to provide a targeted method for controlling invasive and problem feral cats.
The rice-sized implants are injected just under the skin of native animals, where they remain inert, only activating when digested by a feral predator.
UniSA PhD student and 2021 recipient of an Australian Wildlife Society research grant, Kyle Brewer, said the result was deadly.
"Feral cats present a catastrophic threat for Australia's wildlife as they occur across more than 99 per cent of Australia's land area and kill more than 815 million mammals each year, the majority of which are native species," Mr Brewer said.
"Smaller, meal size mammals are most at risk, especially ground-dwellers such as the bilby, bettong and quoll.
"Efforts to remove feral cats from a native landscape have had limited success, making it near impossible to re-establish threatened native populations outside a fenced area.
"Invariably, when native mammal reintroduction schemes are activated, they're swiftly wiped out by an incursive feral cat."
Invariably, when native mammal reintroduction schemes are activated, they're swiftly wiped out by an incursive feral cat.
- Kyle Brewer, UniSA
Mr Brewer said by injecting native species with a PPI before they were reintroduced to their natural environment, there was a protective buffer that aimed to take out the feral invader in one stroke.
"If a feral cat successfully preys upon one of the PPI-injected mammals, it eats the implant, which activates in the cat's gastric system causing poison release and death," Mr Brewer said.
"Ultimately, this protects the remaining native animal population."
The PPIs are covered by a protective coating and contain a toxin derived from a natural poison in native plants. They present no danger to tolerant native mammals but are deadly once the toxin is activated in the introduced predator's stomach.
Brewer's project is a collaborative effort, with researchers from local ecology groups, Ecological Horizons and Peacock Biosciences, and the University of Adelaide, already trialing PPIs in South Australia.
Currently, 30 bilbies have been implanted with PPIs at Arid Recovery, a 123 square km wildlife reserve in South Australia's north. Results from this trial are expected to demonstrate the effectiveness of the technology and lead to its commercialisation.
Feral cats threaten the survival of more than 100 native species in Australia and have caused the extinction of many ground-dwelling birds and small to medium-sized mammal species.