Australian scientists are giving crocodiles a taste of deadly cane toads.

Researchers have devised an innovative way to protect freshwater crocodiles from the lethal threat of invasive cane toads. 

The technique, known as conditioned taste aversion (CTA), involves making crocodiles associate the taste of cane toads with nausea.

Between 2019 and 2022, researchers deployed over 2,000 cane toad carcasses treated with a nausea-inducing chemical across the Kimberley region. 

Crocodiles that consumed the bait became mildly ill, deterring them from eating real cane toads later.

The project, a collaboration between Macquarie University scientists, Bunuba Indigenous rangers, and the Western Australian Department of Biodiversity, Conservation and Attractions (DBCA), aims to teach crocodiles to avoid eating these toxic amphibians.

Macquarie University researchers have documented a 95 per cent decrease in crocodile deaths in baited areas, with the effects lasting for years. 

Bunuba rangers have observed that crocodiles quickly learned to avoid the bait, ultimately choosing to eat safer options like chicken necks.

This project not only aids crocodile survival but also offers a new tool for combating invasive species. 

“Together we've shown that collaborations between academics, Indigenous rangers, and land management agencies can be really effective for conservation science,” said DBCA’s Sara McAllister. 

The team plans to expand CTA to other regions and species impacted by cane toads, offering a hopeful solution to the ongoing threat posed by these invasive predators.