Cane toads: these four-pound poisonous toads wreak havoc on Australian ecosystems. They displace native species that share their niche, kill predators in swathes due to their toxicity, and consume huge amounts of "good" species (such as dung beetles). But a clever research collaboration between the University of Sydney, Western Australia's Parks and Wildlife, and BalanggarraRangers may at least help some of Australia's unluckiest native predators: yellow-spotted monitor lizards, whose populations have dropped by 90%
The researchers trained wild lizards to stop eating cane toads by feeding them young, less poisonous toads. The lizards quickly realized that the toads were unpalatable, but lived to see another day (unlike lizards who prey on the toxic adults). In other words, they learned to stop eating cane toads!
When the wild lizards were tracked after their training session, the researchers found that over half of the 16 trained lizards survived, whereas all but one of 31 untrained monitor lizards died (due to cane toad consumption and other causes). In other words, the program of ecological immunization worked. Animal learning may indeed be the newest tool of conservationists.
Thank you to resident Aussie Elliott Bannan for sending along this article!
Scientists have devised a radical solution to reduce the damaging impact of Australia's deadly cane toads. They have trained wild monitor lizards, known locally as goannas, not to eat the toxic amphibians. They did this by feeding the reptiles small, less potent cane toads. Many that tried the toads once did not make the same mistake again. The researchers say that extending the trial could help the continent's wildlife. The study is published in the Royal Society journal, Biology Letters. Lead researcher Georgia Ward-Fear, from the University of Sydney, said: "We've been very surprised by the results, by the amount of time that some of these lizards have actually retained this knowledge and survived in the presence of a high-density of cane toads, which is basically unheard of in the wild."