Wildlife predators outfoxed with chemical baits

A baiting trial conducted in south-eastern Australia has returned promising results in a bid to prevent predators from killing native species.

Scientists from The Australian National University and the University of South Australia used baits of fried deboned chicken containing capsules of levamisole, a chemical that induces nausea and vomiting.

Over three periods, untreated baits were laid, followed by levamisole-containing baits and untreated baits again.

During the final period, the number of baits taken by red foxes in the area fell by 30 per cent, suggesting the animals had consumed the chemical-laden baits, had fallen ill, and were reluctant to go back for seconds.

Researchers say the study shows it's possible to condition foxes to avoid food sources based on their unique odour, and ultimately this strategy may help protect vulnerable wildlife.

They say the non-lethal tactic for keeping predators at bay may be potentially more effective than shooting, trapping and poisoning in certain contexts.

UniSA Associate Professor Anton Blencowe said invasive predators were responsible for almost 60 per cent of all bird, mammal, and reptile extinctions globally, so it was critical to find ways to mitigate their impacts on native wildlife.

"Existing lethal control methods can be counterproductive in some situations, with predators capable of adapting their behaviour and becoming harder to control," he said.

A range of encapsulated nausea-inducing agents could be injected into food sources, such as eggs or animal carcasses, so the predator associated the symptoms with the food odour and not the chemical.

Microencapsulation, where the agent particles were minimised, could also be used to hide textures and prevent the capsule from being accidentally broken open during consumption.

Scientists said more research was needed to determine the best chemical and doses to be used.

Australian Associated Press