Introducing species to areas outside their historical range to secure their future under climate change is a controversial strategy for preventing extinction. While the debate over the wisdom of this strategy continues, such introductions are already taking place. Previous frameworks for analysing the decision to introduce have lacked a quantifiable management objective and mathematically rigorous problem formulation. Tracy Rout and colleagues believe they have filled this gap by developing the first rigorous quantitative framework for deciding whether or not a particular introduction should go ahead, which species to prioritize for introduction, and where and how to introduce them. The framework can also be used to compare introductions with alternative management actions.
At present, decisions to move species are being made by wildlife managers around the world using a mix of subjective judgement and scientific prediction. The researchers have taken a lot of the guesswork out of this process. This new framework takes into account the benefit of moving a species based on the likelihood it
will go extinct in its original habitat as the local climate becomes hostile, the likelihood that a breeding population can be established at a new site, and the value or importance of the species. The ecological cost depends on the potential for the species to adversely affect the ecosystem at the new site. Species are considered
candidates for re-location only if the benefit of doing so is greater than the ecological cost.
The framework is intended to support the revised IUCN guidelines for re-introductions and other conservation translocations, which explicitly calls for structured decision-making frameworks for conservation introductions.
Rout TM, E McDonald-Madden, TG Martin, NJ Mitchell, HP Possingham & DP Armstrong (2013). How to decide whether to move species threatened by climate change. PLoS ONE 8(10): e75814. doi:10.1371/journal.pone.0075814