ScienceDaily (Dec. 4, 2012) — The effort to stop the irreversible spread of foxes in Tasmania is at a critical stage with many native species at risk of extinction, new research by University of Canberra ecologists and their collaborators published in the British Ecological Society’s Journal of Applied Ecology shows.
Using DNA detection techniques developed at the University, the team mapped the presence of foxes in Tasmania, predicted their spread and developed a model of their likely distribution as a blueprint for fox eradication, but swift and decisive action is needed.
University of Canberra professor in wildlife genetics and leader of the team, Stephen Sarre, found foxes are widespread in northern and eastern Tasmania and the model developed by his team forecasts they will spread even further with likely devastating consequences for the island’s wildlife.
“There’s nothing fantastic about foxes being in Tasmania. If we allow them to establish themselves we could see a catastrophic wave of extinction across the island,” Professor Sarre said.
“This research shows foxes are on the verge of becoming irreversibly present in Tasmania,” he said. “Their apparent widespread distribution indicates that the eradication effort is at a critical point and that there is no time to lose.”
Professor Sarre and colleagues used forensic DNA tests combined with collections of fox scats to detect and map the distribution of the predator in Tasmania.
Their detective work, in partnership with Tasmania’s Fox Eradication Program, represents one of the largest surveys of its kind worldwide and provides the first systematic examination of the distribution of foxes in the island, following evidence and allegations that indicate a long history of isolated introductions.
According to Professor Sarre, the widespread nature of the predator distribution in Tasmania reveals that targeting only fox activity hotspots for eradication is unlikely to be successful.
“The recently adopted plan of baiting all highly suitable fox habitats is the right one given the widespread fox distribution that we’ve found.
“The present situation could be as serious a threat to the pristine Tasmanian environment as the previous extinction wave was to Australia’s mainland fauna, following the arrival of Europeans and which has so far wiped out more than 20 species.
“We suggest an increased effort and an even more focused approach to maximize the chances of a successful eradication. Otherwise, Australia stands on the precipice of another major episode of mammalian extinctions.”
The organisations involved in the research include the University of Canberra, Arthur Rylah Institute, NSW Department of Primary Industry, and Tasmanian Department of Primary Industry Parks Water and the Environment collaborating, with and partially funded by, the Invasive Animals CRC.
• From the Sarre et al paper published today in the Journal of Applied Ecology
Title: Foxes are now widespread in Tasmania: DNA detection defines the distribution of this rare but invasive carnivore
The enormous scale and breadth of the distribution of fox scats revealed by our analyses indicate that fox eradication processes will need to be implemented on a very wide scale if they are to succeed. Indeed, a recent external review of the Fox Eradication Program (Parkes & Anderson 2009) recommended a change from the tactical approach currently in place to that of a pre-emptive approach where baiting is rolled out across all suitable habitat on the island. We would go further than that. Our data suggest that foxes could be on the verge of becoming established irreversibly in Tasmania. Given their apparent widespread distribution, the moment may even already have passed for a feasible eradication although we do not suggest that now is the time to stop.
Under the current planning and funding, a single baiting of all highly suitable fox habitat will take 5 years. We suggest that given the widespread fox distribution revealed here, such a timeframe will result in failure. Rather, we suggest that a massive up-scaling of effort and perhaps more focused approach is going to be required to maximize the chances of a successful eradication. Otherwise, Australia stands on the precipice of a third major wave of mammalian extinctions – this time focused on the island of Tasmania.