Translocations as bioassays of recent environmental change

Background/Question/Methods

Conservation translocation is an umbrella term for any deliberate movement of plants or animals for conservation purposes and includes reintroductions where the recipient site is within the species’ indigenous range, and conservation introductions (C.I.) which involve moving individuals beyond the range. Reintroductions are regularly used for threatened species management but with mixed success. Poor post-translocation survival might occur because recipient sites are only superficially like those supporting extant populations and practitioners do not account for the potential for recent climate change to have rendered parts of the former range unsuitable. In a meta-analysis of plant translocations, reintroductions resulted in higher mortality than C.I. Whilst this is based on a very small sample of C.I. attempts, it suggests that failed reintroductions might be attributable to recent climate change whilst successful C.I. could indicate a shift in the spatial distribution of suitable climatic conditions beyond the species’ former range. Discriminant function analysis was used to explore the relative importance of a wide range of factors associated with the success of plant reintroduction and C.I. attempts.  Specifically, this analysis identifies the key variables that discriminate between successful and failed translocation attempts through multivariate comparison of the species’ indigenous range.

Results/Conclusions

A database of >300 plant translocations were identified during a systematic review completed in 2011 and are currently being analysed. Preliminary results indicate that small scale factors such as site-specific management often play a critical role in affecting the success of plant translocations. However, in many cases, climatic factors are identified as being important and in particular, variables associated with water availability are key to post-translocation survival.  In addition to identifying the signature of climate change, this study has identified gaps in translocation feasibility assessment and monitoring.  The presentation concludes by explaining how practitioners can avoid undertaking translocations that succumb to climate impacts and how a well-designed monitoring program can enable adaptive management approaches.