Frigid nights may halt Australia’s warty green menace - August 27, 2008
Posted on behalf of Amber Dance
Cane toads - big, poisonous hoppers up to a kilogram in weight - have been marching steadily across Australia since they were invited over in 1935, but no-one knows quite how far they could go. Now scientists at the University of Melbourne say south Australians can heave a collective sigh of relief at a toadless life – for the time being.
The toads were inported to eat the beetles plaguing the sugar cane crops; instead they gobbled up everything else, in the process evolving longer legs to expand their territory across the eastern and northern coast of the continent at a rate of 1.8 kilometers a night, and inspired one of the most hilarious science documentaries of all time. The residents of Darwin await their inevitable approach with automobiles and cricket bats at the ready, planning to squish as many as possible.
But the cold may slow them down.
In a study in the current issue of Ecography the Melbourne scientists suggest that some parts of Australia may be too chilly for the cold-blooded amphibians.
Previous theoretical studies compared the climate in the toads’ current range to the rest of Australia, to predict the toads could make a happy home across the continent in Perth and Adelaide. Michael Kearney and colleagues, instead, went straight to the toads to determine their potential range. They raced toads at different temperatures, and found the animals are so sluggish they can barely hop below 15 degrees Celsius. “The toads cannot survive in much of South Australia because they would be too cold to move about and forage or spawn,” Kearney said in a University press release.
The weather should slow the toads in Sydney and Perth, and stop them in their tracks before they reach Adelaide, Melbourne or Hobart. Global warming, however, could allow the toads to progress into Sydney and Perth by 2050.
Of the Australian press only The Age seems to have picked this up at the moment: ‘Melbourne's cool reception to stop cane toad’.
Image: cane toad by Burning Image / Nam Nguyen via Flickr.
Comments
Think you had better think again.
We live in Central Queensland. Over the past 2 years we have exterminated approx 11K toads. I am born and bred South Aust, with relatives in Victoria, I know the climates. Our climate here is remarkably similar. The toads will do very well there. They are tough, evolving faster than science is willing to admit. We have frosts, we have minus and low degree nights and some low temp days and drought. We still are amazed that we even had a toad call in July after some rain. eg.They hide in mulch and in pots to stay warm. They are probably learning to burrow. In the field this is plain not true about temp stopping them. Sure, numbers are sometimes less in winter, we toad daily all year as possible. They decimate our native wildlife. Extinct the toad in Australia! Am in the process of writing our findings. We have some great data pre and post toads. Get a burst of warm weather and rain and there they are! Nadia
Posted by: nadia marmach | August 27, 2008 12:24 PM