Cane toad. The amphibians were introduced to Australia to control a beetle but have become an aggressively invasive species. Photo: REUTERS

Provided by Society for Experimental Biology
July 1, 2010 As global warming threatens many animal species with extinction, the cane toad is set to flourish with increasing temperature. This is a major cause for concern as the cane toad, once introduced to Australia as agricultural pest-control of the cane beetle, is an already highly invasive species and considered a pest in Australia. The researchers present their new findings at the Society for Experimental Biology Annual Conference in Prague on Friday, July 2, 2010. “The negative effect of high temperature does not operate in Cane Toads, meaning that toads will do very well with human induced global warming”, explains Professor Frank Seebacher from the University of Sydney. Unlike fish and other cold-blooded creatures, whose oxygen transport system suffers at high temperatures, the cardiovascular system (heart and lungs) of Cane Toads performs more efficiently. The researchers present their new findings at the Society for Experimental Biology Annual Conference in Prague on Friday 2nd July 2010. When tested over an ambient temperature range of 20 – 30 ˚C, Cane Toads acclimatised perfectly to increased temperatures and resting oxygen demands remained constant. Furthermore, the efficiency of the oxygen transport system in the Cane Toad increased with increasing temperature, showing not only an ability to function over a broad thermal range but remarkably, a preference for higher temperatures. This is in contrast to previous studies suggesting an increase in temperature results in a higher basic oxygen demand, coupled with decreased efficiency of the circulation system, leading to oxygen starvation. “Warmer temperatures are advantageous and there is no indication that high temperatures limit oxygen delivery”, explained Professor Seebacher. …

Warmer is better: Invasive cane toads set to thrive under global warming