Featured Research

from universities, journals, and other organizations

Racing Cane Toads Reveals They Get Cold Feet On Southern Australia Invasion

Date:
August 27, 2008
Source:
University of Melbourne
Summary:
Cane toads weren't allowed to compete in the Olympics, but scientists have raced cane toads in the laboratory and calculated that they would not be able to invade Melbourne, Adelaide or Hobart and are unlikely to do well in Perth or Sydney, even with climate change.

Cane toad, after a long journey. Scientists have calculated that cane toads would not be able to invade Melbourne, Adelaide or Hobart and are unlikely to do well in Perth or Sydney, even with climate change.
Credit: iStockphoto

Cane toads weren’t allowed to compete in the Olympics, but scientists have raced cane toads in the laboratory and calculated that they would not be able to invade Melbourne, Adelaide or Hobart and are unlikely to do well in Perth or Sydney, even with climate change.

Related Articles


According to research by Dr Michael Kearney, from the Department of Zoology at the University of Melbourne, and collaborators from Australia and the USA, the cane toad’s march will grind to a halt once it is physically too cold for the toads to hop.

“The cane toads cannot survive in much of Southern Australia because they would be too cold to move about and forage or spawn” said Dr Kearney.

Their study is unique in that it is based on an understanding of the capabilities of the toad itself whereas many other studies – some predicting that Melbourne would be invaded by the toads – are based on correlations between climate and the places the toads are living at now, which can lead to errors.

Since their introduction to Australia in the 1930s, cane toads have been steadily advancing across Australia and have already invaded Brisbane and Darwin. Once used as pest control, the toads are now a devastating pest themselves so an accurate prediction of their final range and rate of movement is essential.

If there were a cane toad Olympics, all eyes would be on the weather: because they are cold-blooded, the toad’s ability to move depends on its body temperature which fluctuates with its environment.

Dr Kearney and his colleagues, including Dr. Ben Phillips from the University of Sydney and Dr. Chris Tracy from Charles Darwin University, set up a 2m sprint event for toads at a range of different temperatures to see what temperatures would slow toads down the most.

The team used field-collected toads from four populations across the invasion front.

“We found that cane toads can barely hop once they get below about 15 degrees Celsius”, said Dr. Tracy. “Their range would also be constrained by the limited availability of water for their tadpoles in some parts of Australia”.

After racing their toads, Kearney and his colleagues used sophisticated computer models developed by Dr Warren Porter at the University of Wisconsin, Madison USA, to predict how cold toads would get at different times of the year across Australia.

They found that it is so warm and wet around Darwin that toads there can hop more than 50 kms per year. However, the cooler, drier conditions around Sydney or Perth mean that toads can barely manage 1 km per year. And they couldn’t move at all under typical weather conditions in Adelaide, Melbourne and Hobart.

They found that toads have particular difficulties in parts of southern Australia with what are known as Mediterranean climates – places with cold wet winters and warm dry summers.

“These are perfect conditions for growing wine, but you are unlikely to meet a toad at a winery” said Dr Kearney. In many of these places the air temperature at night – the active period for toads - is often above 15 degrees Celsius, but this only happens during summer, and evaporation in the dry summer air cools them down too much.

“Our study is particularly helpful in predicting where cane toads could live under climate change because we have identified a cause-and-effect way that climate limits the toads”. Dr. Kearney said.

“In one way it is obvious why dry conditions are bad for frogs – they lose too much water” explained Dr. Kearney. “But having wet skin also provides frogs with a thermal challenge because the evaporating water takes heat away from their bodies and often makes them colder than the air.”

They found that a moderate global warming could allow toads to move 100 km further south than their present limit by 2050. This would make conditions in Sydney slightly better for toads, and the only other city at risk of toad invasion under this scenario would be Perth.

The work is published in this month’s Ecography journal.


Story Source:

The above story is based on materials provided by University of Melbourne. Note: Materials may be edited for content and length.


Cite This Page:

University of Melbourne. "Racing Cane Toads Reveals They Get Cold Feet On Southern Australia Invasion." ScienceDaily. ScienceDaily, 27 August 2008. <www.sciencedaily.com/releases/2008/08/080826115906.htm>.
University of Melbourne. (2008, August 27). Racing Cane Toads Reveals They Get Cold Feet On Southern Australia Invasion. ScienceDaily. Retrieved March 5, 2015 from www.sciencedaily.com/releases/2008/08/080826115906.htm
University of Melbourne. "Racing Cane Toads Reveals They Get Cold Feet On Southern Australia Invasion." ScienceDaily. www.sciencedaily.com/releases/2008/08/080826115906.htm (accessed March 5, 2015).

Share This


More From ScienceDaily



More Plants & Animals News

Thursday, March 5, 2015

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

Raw: Tourists Visit Rare Grey Whales in Mexico

Raw: Tourists Visit Rare Grey Whales in Mexico

AP (Mar. 4, 2015) Once nearly extinct, grey whales now migrate in their thousands to Mexico&apos;s Vizcaino reserve in Baja California, in search of warmer waters to mate and give birth. Tourists flock to the reserve to see the whales, measuring up to 49 feet long. (March 4) Video provided by AP
Powered by NewsLook.com
Australian Museum Shares Terrifying Goblin Shark With the World

Australian Museum Shares Terrifying Goblin Shark With the World

Buzz60 (Mar. 4, 2015) The Australian Museum has taken in its fourth-ever goblin shark, a rare fish with an electricity-sensing snout and &apos;alien-like&apos; jaw. Mike Janela (@mikejanela) takes a look. Video provided by Buzz60
Powered by NewsLook.com
New Hormone Could Protect Against Diabetes And Weight Gain

New Hormone Could Protect Against Diabetes And Weight Gain

Newsy (Mar. 4, 2015) A newly discovered hormone mimics the effects of exercise, protecting against diabetes and weight gain. Video provided by Newsy
Powered by NewsLook.com
Prince William Calls for Unified Effort Against Illegal Wildlife Trade

Prince William Calls for Unified Effort Against Illegal Wildlife Trade

Reuters - Entertainment Video Online (Mar. 4, 2015) Britain&apos;s Prince William pledges to unite against illegal wildlife trade on the final day of his visit to China. Rough cut - no reporter narration Video provided by Reuters
Powered by NewsLook.com

Search ScienceDaily

Number of stories in archives: 140,361

Find with keyword(s):
Enter a keyword or phrase to search ScienceDaily for related topics and research stories.

Save/Print:
Share:

Breaking News:

Strange & Offbeat Stories


Plants & Animals

Earth & Climate

Fossils & Ruins

In Other News

... from NewsDaily.com

Science News

Health News

Environment News

Technology News



Save/Print:
Share:

Free Subscriptions


Get the latest science news with ScienceDaily's free email newsletters, updated daily and weekly. Or view hourly updated newsfeeds in your RSS reader:

Get Social & Mobile


Keep up to date with the latest news from ScienceDaily via social networks and mobile apps:

Have Feedback?


Tell us what you think of ScienceDaily -- we welcome both positive and negative comments. Have any problems using the site? Questions?
Mobile: iPhone Android Web
Follow: Facebook Twitter Google+
Subscribe: RSS Feeds Email Newsletters
Latest Headlines Health & Medicine Mind & Brain Space & Time Matter & Energy Computers & Math Plants & Animals Earth & Climate Fossils & Ruins