Temperature rises can drastically alter relationships between predator and prey, including the success of invasive species, new research from the University of Sydney has shown. This was published in Proceedings of the Royal Society B online before print on August 1.
“We found the higher temperature levels climate change is predicted to bring about will reduce the number of attacks by the Australian bass on the mosquitofish,” said Professor Frank Seebacher. “At the same time the escape speed of the mosquitofish increased. This means the Australian bass was much less successful in catching the mosquitofish, an invasive species that is a major part of the bass diet.”
At first, as the temperature in the fish’s environment was raised the bass made more attacks but as the temperature increased to the range likely to be introduced by climate change (30 degrees celsius) its attack rate dropped.
“Importantly we have shown that while the range of higher temperatures predicted to occur with climate change might not directly kill a species, the impact on its relationships with its prey can threaten it and bring about complex changes to the ecosystem,” said Professor Seebacher.
In an evolutionary sense, mosquitofish might be expected to adapt better to temperature changes than bass because it lives in a wide range of thermal conditions, from hot springs to cool mountain habitats. The bass, by contrast, is restricted to coastal areas in temperate parts of eastern Australia. “Interestingly while the bass experiences a much narrower and less varied range of temperatures than the mosquitofish it was still able to spontaneously adapt to changes in temperature. So evolutionary theory alone cannot explain its response — which raises interesting questions about what mechanism it is using to cope with this environmental change.”
The above news item is reprinted from materials available at The University of Sydney News. Original text may be edited for content and length.
(Source: The University of Sydney News, 02.08.2012)
