Assisted colonization is a techno-fix.

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 conservation 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 policymakers and the public. Here we propose three important additional considerationswhich lend further support to the view that the widespread implementation of assisted colonization 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 biodiversity 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 landscapes [4]. Third, without sufficient emphasis on reversing fragmentation, ongoing intensification of production landscapes 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 increasing dependence on assisted colonization. This reinforcing feedback could contribute to an undesirable path dependency 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 bandaid to buy time for some species, but not a technological