Top dogs: dingoes increase biodiversity of native mammals
17 June 2009
Research by University of Sydney scientist, Dr Mike Letnic, has shown that Australia's top predator, the dingo, plays an important role in maintaining the balance of nature and that reintroducing or maintaining existing dingo populations could increase biodiversity across more than 2 million square kilometres of Australia.
Dr Letnic, from the School of Biological Sciences, showed that dingoes have a positive effect on Australian native mammals by suppressing populations of other introduced species, particularly foxes.
The research, published in the journal Proceedings of the Royal Society B, contradict the long-held belief that dingoes are invasive predators that pose a threat to native wildlife.
Dr Letnic's study consisted of biodiversity surveys along the length of the dingo fence, which is the longest fence in the world and runs from the coast in South Australia, along the NSW border, and through Queensland to keep dingoes out of the south east of Australia.
Where dingoes had been exterminated, Dr Letnic found increased abundances of introduced red foxes and herbivores, while small native mammals and grasses were lost.
"Dingoes appear to suppress the impacts of red foxes, so we predict that maintaining or reintroducing dingo populations would benefit threatened native mammals across more than 2 million square kilometres of Australia," said Dr Letnic.
The dingo, Australia's largest predator, is an alien introduced less than 5 000 years ago and is subject to large-scale extermination to protect agricultural animals such as sheep. The status of dingoes as a native or introduced species in Australia is ambiguous because of their recent arrival.
"Alien predators often have catastrophic effects on ecosystems and are thought to be more harmful to biodiversity than native predators," explained Dr Letnic.
"Since European settlement of Australia there has been a mass extinction of mammals weighing less than 10 kg. These extinctions are thought to have been driven by a number of factors, particularly predation by introduced red foxes," said Dr Letnic.
"Our research suggests that maintaining or restoring dingo populations may be a useful strategy to reduce the predatory impacts of foxes on small and medium sized mammals.
"This supports the notion that the dingo's functional role as top-predator is ecologically more significant than the classification of this species as an undesirable alien pest. To put it simply the dingo is now nature's keeper," said Dr Letnic.
Contact: Katynna Gill
Phone: 02 9351 6997