Is translocation a useful tool to sustain species at risk?

Background/Question/Methods:  Many animal (and plant) species are officially listed as threatened or endangered at the state or Federal level, and many more are considered at-risk of being so listed. It is often suggested that remaining individuals be moved from places where they still survive to another site. In the case of the gopher tortoise in Florida, tens of thousands of animals are proposed for relocation to remove them from the risk of death on major construction sites. This is one purpose for relocation, and there are many others. Will they maintain themselves at their new sites? This is not clear. Based on cases where there are follow-up data, we believe survival at the new location is possible, but universal success should not be assumed. Should the proposed relocations be subjected to closer scrutiny, especially with respect to the new habitat and plans for management and monitoring? The new Florida tortoise management guidelines set a new, and higher, standard in this aspect which has not been seen previously. What about other species? We evaluated >100 published reports of translocations, focusing on declining species, asking the following questions, among others.
Results/Conclusions: Does it make a difference what the reason behind the relocation might be: to re-establish an extirpated population, extend the range, create a harvestable population in a new location, supplement an existing population? Are there special concerns relating to the life stage being utilized? Adults? Juveniles? Eggs? Will “head starting” the animals increase survival? The results of our review of these and other aspects of translocation reflect the generally chancy efficacy of this practice for many species at risk, and the need for development of policy guidance which incorporates adequate precautions to avoid adverse and unintended consequences..