Protecting our precious native animals

Rick Shine gets up close with a menacing cane toad

Professor Rick Shine, from the School of Biological Sciences, is leading the fight to save our native animals from the menace of cane toads.

In Queensland, the species is so abundant that you’re likely to run over a toad a day with your car. Cane toads are invasive throughout Australia and thus far, we’ve been unable to find a method to permanently lower their numbers. Even killing 98 out of 100 toads won’t help, because the two left can produce up to 30,000 eggs overnight.

While plenty of Australians do their best in the cane toad cull, using whatever they can to put a (literal) dent in the toad population, Professor Shine’s research has provided new, ecologically informed approaches to controlling the number of toads in an area, and their effect on native animals.

His work is based on chemical communication systems and host-parasite biology, for example infecting toads with the lungworm parasite in large quantities to help control their numbers, and releasing large quantities of sterilised males, who will mate with females, resulting in the females laying unfertilised eggs.

And these approaches are delivering results, as Professor Shine highlighted after being honoured for the excellence and impact of his research on the ecology and evolutionary biology of Australian reptiles and amphibians in the Plant and Animal Research category of the NSW Science and Engineering Awards.

"Working on the ecological impacts of invasive cane toads, our results have led to a major rethink by federal authorities on how to mitigate those impacts," he says. "Specific work on cane toad pheromones has revealed novel opportunities to control cane toads by exploiting the chemical arsenal that toads use to compete with each other."

Recipe for disaster

For a snake, or a goanna or even a crocodile, a juicy toad represents their final meal. Just swallowing one is enough to kill an animal, thanks to the extremely toxic secretions that toads have in sacs behind their eyes.

Professor Shine’s team has experimented with teaching quolls (small marsupials) to associate eating cane toads with the unpleasant side effect of nausea. By feeding the quolls smaller toads, and adding in a nausea-causing substance, the marsupials learned that eating a cane toad would leave them feeling very ill indeed.

The small quantities they ate weren’t deadly and when released back into the wild, the trained quolls survived up to five times longer than those that didn’t undergo training (find out more at livescience.com). Professor Shine’s team is now working on educating goannas and bluetongue lizards, which are part of a list of endangered species in Australia.

Professor Shine is widely admired for his decades of research on snakes and his conservation and public communication efforts on reptiles and amphibians.

He won the 2011 Eureka Prize for Promoting Understanding of Australian Science Research. The judges noted that he has been transforming the public debate about cane toads, with his websites, media appearances and magazine articles replacing myths with fact.

Most recently Professor Shine won the Australian Innovation Challenge Environment award for his research into using pheromones to reduce cane toad numbers. To learn more about his research, visit the Cane Toads in Oz website.