Letters Assisted colonization is a techno-fix Ioan Fazey 1, 2 and Joern Fischer 3 1 Institute of Biological, Environmental and Rural Sciences, Aberystwyth University, Llanbadarn Campus, Aberystwyth, Wales SY23 3AL, UK 2 Current address: School of Geography and Geosciences, St. Andrews University, St. Andrews, Fife KY16 9AL, UK 3 Fenner School of Environment and Society, The Australian National University, Canberra, ACT 0200, Australia In a recent Opinion article in Trends in Ecology & Evolution, Ricciardi and Simberloff [1] argue that species translocations are not a viable conservation strategy to deal with threats such as climate change, because conser- vation biologists lack sufficient understanding of the associated risks. We agree with the basic tenet of their argument that the attention and credibility given to such schemes [2] is worrying and that it might send an overly optimistic message about assisted colonization to policy- makers and the public. Here we propose three important additional considerations which lend further support to the view that the widespread implementation of assisted colo- nization will be inappropriate, especially when the broader social-ecological context of threatened species conservation is taken into account. First, assisted colonization does not address the root causes of extinction (i.e. in this context, human-induced climate change and habitat fragmentation). Instead, it is a ‘techno-fix’ restricted to treating the symptom of biodiver- sity loss, implying that no fundamental change in human activities is required. Second, widespread adoption of assisted colonization would divert resources, effort and expertise away from ambitious large-scale restoration [3] and innovative management strategies in production land- scapes [4]. Third, without sufficient emphasis on reversing fragmentation, ongoing intensification of production land- scapes will lead to even fewer species being able to move through them. Left with a yet more inhospitable matrix, both human and ecological response options to climate change will be further reduced, thereby potentially increas- ing dependence on assisted colonization. This reinforcing feedback could contribute to an undesirable path depen- dency similar to others documented in natural resource management, where technological solutions, once adopted, are the only viable options left [5–7]. On this basis, assisted colonization is, at best, a band- aid to buy time for some species, but not a technological cure to the extinction crisis. Unforeseen risks, as high- lighted by Ricciardi and Simberloff [1], need to be con- sidered. Perhaps more importantly, we need to ask whether we want to build momentum for yet another techno-fix in natural resource management or try to build momentum to foster large-scale restoration, integration of conservation and commodity production, and reduction of greenhouse gas emissions. A mix of strategies will always be required for uncertain situations, and assisted colonization might have a place in biodiversity conservation if the risks of introducing species to new areas have been adequately assessed. The role of assisted colonization, however, needs to be carefully considered and will be small relative to other strategies that address the root causes of biodiversity decline. References 1 Ricciardi, A. and Simberloff, D. (2009) Assisted colonization is not a viable conservation strategy. Trends Ecol. Evol. 24, 248–253 2 Hoegh-Guldberg, O. et al. (2008) Assisted colonization and rapid climate change. Science 321, 345–346 3 Soule, M.E. and Terborgh, J. (1999) Conserving nature at regional and continental scales—a scientific program for North America. Bioscience 49, 809–817 4 Stinner, D.H. et al. (1997) Biodiversity as an organizing principle in agroecosystem management: case studies of holistic resource management practitioners in the USA. Agric. Ecosyst. Environ. 62, 199–213 5 Allison, H.E. and Hobbs, R.J. (2004) Resilience, adaptive capacity, and the ‘lock-in trap’ of the Western Australian agricultural region. Ecol. Soc. 9, 3 6 Anderies, J.M. et al. (2006) Loss of resilience, crisis, and institutional change: lessons from an intensive agricultural system in southeastern Australia. Ecosystems (N. Y., Print) 9, 865–878 7 Holling, C.S. and Meffe, G.K. (1996) Command and control and the pathology of natural resource management. Conserv. Biol. 10, 328–337 0169-5347/$ – see front matter ß 2009 Elsevier Ltd. All rights reserved. doi:10.1016/j.tree.2009.05.003 Available online 2 July 2009 Corresponding author: Fazey, I. (ioan.fazey@st-andrews.co.uk). Update Trends in Ecology and Evolution Vol.24 No.9 475