The cane toad, our most invasive pest is responsible for endangering many of our native species. Introduced to Australia in 1935, the amphibian was brought over from Hawaii’s Bureau of Sugar Experiment Stations in an attempt to rid Australian sugar cane crops of the native grey-backed cane beetle. The introduction of the cane toad had no effect on the beetle’s numbers. Instead, the toad multiplied, wreaking havoc on our native flora and fauna.
All efforts to curtail the spread of the pest have failed, now there are more than 200 million cane toads in Australia.
Image:The spread of cane toads in Australia from 1940 to 1980 in five-year intervals. By Froggydarb at the English language Wikipedia, CC BY-SA 3.0,
One species which has been particularly affected by the cane toad is the northern quoll. The quoll is native to the Northern territory, and since the cane toad invasion quoll numbers have dwindled. The cane toad has been in Queensland for over 70 years and in the Northern Territory for 35 years. As a result, the Queensland quolls have learnt to stay clear of the poisonous cane toad. Ella Kelly from the University of Melbourne explains:
Queensland quolls are toad-smart, which means they avoid cane toads as a prey item
In light of this, researchers are undertaking a unique experiment on Indian Island just 41 kilometres west of Darwin. Essentially using the Queensland quoll as an example, they are attempting to train native animals such as the northern quoll to avoid the dangerous cane toad.
We're hoping that that these toad-smart quolls can help us improve the management of these threatened populations in the NT and Western Australia.
The quolls were trained to avoid cane toads by feeding them small amounts of toad spiked with a chemical that will induce sickness. Ben Phillips from the University of Melbourne explains:
It's exactly the same response as when people drink too much alcohol and feel really sick; they will often not be able to stand the smell of that particular drink anymore
A technique known as aversion therapy, designed to associate an undesirable action with an unpleasant effect. It is hoped that when these quolls are released back into the wild, they will breed, teaching their offspring to avoid eating the toads as well.
If all is successful, the team will use this training on other native animals.
Header: Northern Quoll, Wikimedia Commons