Coming to Terms with the Concept of Moving Species Threatened by Climate Change – A Systematic Review of the Terminology and Definitions

Abstract

Intentional moving of species threatened by climate change is actively being discussed as a conservation approach. The debate, empirical studies, and policy development, however, are impeded by an inconsistent articulation of the idea. The discrepancy is demonstrated by the varying use of terms, such as assisted migration, assisted colonisation, or managed relocation, and their multiple definitions. Since this conservation approach is novel, and may for instance lead to legislative changes, it is important to aim for terminological consistency. The objective of this study is to analyse the suitability of terms and definitions used when discussing the moving of organisms as a response to climate change. An extensive literature search and review of the material (868 scientific publications) was conducted for finding hitherto used terms (N = 40) and definitions (N = 75), and these were analysed for their suitability. Based on the findings, it is argued that an appropriate term for a conservation approach relating to aiding the movement of organisms harmed by climate change is assisted migration defined as follows: Assisted migration means safeguarding biological diversity through the translocation of representatives of a species or population harmed by climate change to an area outside the indigenous range of that unit where it would be predicted to move as climate changes, were it not for anthropogenic dispersal barriers or lack of time. The differences between assisted migration and other conservation translocations are also discussed. A wide adoption of the clear and distinctive term and definition provided would allow more focused research on the topic and enable consistent implementation as practitioners could have the same understanding of the concept.

Addressing potential local adaptation in species distribution models: implications for conservation under climate change

“…, Hällfors et al. ). As a consequence, we not only needed to consider areas where the species could disperse to on its own in the near future, but also areas where it might migrate under longer climate changes and sites that might be candidates for assisted migration (also called managed relocation).…”

Addressing potential local adaptation in species distribution models: implications for conservation under climate change

“…A common recommendation for choosing the study area is to include areas to which the species could disperse (Merow et al 2013). In this study, we considered conservation under climate change, including possible use of assisted migration to move species to climatically suitable regions (McLachlan et al 2007, Hällfors et al 2014. As a consequence, we not only needed to consider areas where the species could disperse to on its own in the near future, but also areas where it might migrate under longer climate changes and sites that might be candidates for assisted migration (also called managed relocation).…”

Incorporating climate change projections into riparian restoration planning and design

“…Restoration plantings may have the greatest likelihood of long-term success under uncertain future conditions if they include a broad mix of species and genotypes adapted to current and various projected future conditions (Rice and Emery, 2003;Seastedt et al, 2008;Benito-Garzon et al, 2013) and if each species is planted on multiple surfaces near and far from the channel. To avoid introducing novel invasive species, non-local species and genotypes should be limited to those that could be expected to migrate to the site under climate change given time and absence of human barriers to dispersal (Hallfors et al, 2014). Potential adjustments to locations for riparian revegetation efforts along an idealized riparian cross-section given projected changes in streamflow towards higher high and low flows ('higher flows') or lower high flows and low flows ('lower flows').…”