Assisted colonisation in response to climate change

1. Assisted colonisation in response to climate change Mark Stanley Price RSG-ISSG Task Force on Moving Plants and Animals for Conservation Purposes Workshop 678, Jeju

2. Re-introduction guidelines

3. The Translocation Spectrum Is release intentional? Accidental translocations yes no • non-lethal control • rehabilitation release • commercial/recreational • religious • biological control • animal rights liberation • aesthetic • other • Is the primary objective of the release to: • Improve status (of the focal species), or • Restore natural ecosystem functions or processes? no yes Conservation Translocation Is the release within the indigenous range? Conservation Introduction no yes Is the aim of the release to: 1/ Avoid population extinction of focal species at any scale, Population restoration = ASSISTED COLONISATION Are conspecifics present in release area? and / or yes no 2/ Perform an ecological function lost by extinction of an original form, = ECOLOGICAL REPLACEMENT REINFORCEMENT REINTRODUCTION

4. Assisted Colonisation is the intentional movement and release of an organism outside its indigenous range to avoid extinction of populations of the focal species. This is carried out primarily where protection from current or likely future threats in current range is deemed less feasible than at alternative sites.

5. Torreya pine, Torreya taxifolia • Occupies a Pleistocene refuge in Florida, • 1000 individuals, • 1 produced 8 seeds, • No recruitment >20 years, • Moved to cooler climate in Georgia

6. Taxon substitution 2003 1972 Ecological replacement Use of Aldabran tortoise as an analogue for extinct tortoise as part of restoration of Round Island, Mauritius, following elimination of goats and rabbits. Griffiths et al. (2009) Restoration Ecology doi:10.1111/j.1526-100X.2009.00612.x

7. The big caution Global evidence shows that introductions of species outside their indigenous range can frequently cause extreme, negative impacts that can be ecological, social or economic, are often difficult to foresee, and can become evident only long after the introduction.

8. Hence, although risk analysis around a translocation should be proportional to the presumed risks, justifying a conservation introduction requires an especially high level of confidence over the organisms’ performance after release, including over the long-term, with reassurance on its acceptability from the perspective of the release area’s ecology, and the social and economic interests of its human communities. In any decision on whether to translocate or not, the absolute level of risk must be balanced against the scale of expected benefits. Where a high degree of uncertainty remains or it is not possible to assess reliably that a conservation introduction presents low risks, it should not proceed, and alternative conservation solutions should be sought.

9. Any determination that an area is habitat for a conservation translocation should include reassurance that its climate is predicted to remain suitable for the reintroduced species for long enough to achieve the desired conservation benefit, acknowledging the uncertainties inherent in climate projections.

10. 1/ Area-based solutions, 2/ Species-based solutions: improve the viability of extant populations through management interventions such as pathogen, predator or invasive alien species control, food provision, assisted reproduction, or protective fencing, 3/ Social/indirect solutions: establishment of protected areas, changes in legislation or regulations, public education, community-based conservation, financial incentives or compensation on their own or in combination with area- or species-based solutions, 4/ Do nothing: lower risks of extinction compared to those of alternative solutions? Focalspecies might adapt naturally where it is or adjust its range without human intervention. A conservation translocation may be used as one solution amongst these other approaches. Consider alternatives to translocation

11. Paucity of examples: a proactive Conservation Introduction: the case of 2 UK butterflies Translocations started in 2000 small distances beyond current range in direction of climate change. Small skipper, Thymelicus sylvestris, moved 35 km. Results: both colonies expanded 2001-2006, and were thriving in 2008, BUT colonies spread at <1 km/year while isotherms shift 4.5 km/year northwards in northern Britain Marbled white, Melanargia galathea, moved 65 km Willis et al (2008), Cons Letters 2, 45-51

12. Observations • Translocation not the first option? • Adaptability in face of climate change? • Elastic margins? • Micro-evolution rate? Pleiotropic effects.... • Wait and watch, • Experiment and learn, eg butterflies, forest trees, assessments of vulnerability, • What change and what situations are acceptable?

13. Acknowledgements IUCN SSC Task Force on Moving Plants and Animals for Conservation Purposes, Al Ain Wildlife Park & Aquarium Wildlife Conservation Research Unit, University of Oxford

14. Taxon substitution 2003 1972 Ecological replacement Use of Aldabran tortoise as an analogue for extinct tortoise as part of restoration of Round Island, Mauritius, following elimination of goats and rabbits. Griffiths et al. (2009) Restoration Ecology doi:10.1111/j.1526-100X.2009.00612.x

15. Re-introduction guidelines • Published 1998, • In 7 languages, • Short and concise, based on principles, • Led to taxon-specific guidelines. Affirm the convention that organisms should only be released inside historic range, in appropriate habitats etc.