Mitigation-driven animal translocations are problematic
The use of animal translocations as a means to mitigate construction projects and other human developments is a widespread animal-management tool. A paper published today, produced through collaboration of conservationists from San Diego Zoo Global, the U.S. Fish and Wildlife Service, University of Kent UK, University of Newcastle and Amphibian and Reptile Conservation, reviews the success rates associated with these moves from a species-conservation standpoint.
"Mitigation-driven translocations outnumber and receive more funding than science-based conservation translocations," said Ron Swaisgood Ph.D., conservation biologist for San Diego Zoo Global. "Yet the conservation benefit of the former is often unclear, since outcomes are often poor and rarely monitored. There are other, more strategic, priorities where our limited conservation resources should be allocated."
The study, available online ahead of print and scheduled for the March issue of Frontiers in Ecology and the Environment the study estimates that millions of dollars are spent annually on moving animals out of the way of human interference, and may not be meeting the goal of preserving the populations as intended by legislation.
"Because mitigation releases are economically motivated, outcomes may be less successful than those of releases designed to serve the biological needs of species," said Jen Germano, lead author of the paper. "Evidence suggests that many mitigation-driven translocations fail, although the application of scientific principles and best practices would probably improve the success rate."
An additional challenge, pointed out by the paper, is the lack of information accompanying many of these translocations.
"Just determining how many animals have been moved and to what effect is challenging, since records are not kept or are difficult to obtain," said Simon Clulow of the University of Newcastle, Australia. "This documentation is essential if we are to learn lessons and improve our methods."
Researchers point to successful science-based animal relocations and releases as forming good models for the future.
"We've learned a great deal from carefully designed, conservation-driven translocation research over recent years, and this needs to be better applied to mitigation translocations," said Richard Griffiths of the University of Kent, UK. "Unfortunately, mitigation translocations often do not meet the legislative intent of preventing the decline of protected species. This can be changed in the future to give these species a better chance at long-term survival."