Thursday, 28 July 2011

Species relocation under climate change - a hot topic!

A flurry of recent publications indicate to me that the idea of assisted colonization is a hot topic.  Another contribution in this area is from a CSIRO collaboration with UQ and Melbourne Uni, in the new journal 'Nature Climate Change':

Optimal timing for managed relocation of species faced with climate change
Eve McDonald-Madden, Michael C. Runge, Hugh P. Possingham and Tara G. Martin (2011) Nature Climate Change 1 261–265

 This new journal is likely to be highly influential and perhaps also this paper.  It provides a decision framework to enable relocation of species in a timely and proactive fashion under the threat of climate change (or perhaps more likely, human population pressure).  The approach is largely based on theoretical carrying capacities for the source and new region and projections on how they will change over time, with relocation aiming to optimise population size.  The authors try to incorporate uncertainty into their decisions, making the observation that ' There are two key components of climate change that are particularly challenging: management in the face of system changes; and management in the face of uncertainty surrounding these changes.'  It is a very 'theoretical' paper - I would like to see the approach they advocate applied to a practical example.  Maybe that will be a follow-up publication!

  Figure 1: Carrying capacities in the source (KS) and destination (KD) are shown with thick solid and dashed lines respectively; the population size, N, is shown with a thin solid line. The population size represents the state of the system by which decisions are specified. Note, N can decline with KS or increase towards KS, depending on the starting population size. The premise of managed relocation is that the suitability of the source habitat will decline with climate change and a destination habitat will become suitable. cS and cD represent the times at which half the suitable habitat in the source and destination populations are expected to be lost. The demographic cost of moving a population is expressed as the relocation survival rate, ϕ. The thin dashed line represents population change after relocation based on ϕ.

No comments:

Post a Comment