Existing evidence on the outcomes of wildlife translocations in protected areas: a systematic map
Authors: Langridge Joseph , Sordello Romain , Reyjol Yorick 
Published: October 2021

Background

Ecosystem degradation, mainly through overexploitation and destruction of natural habitats, is a well-known threat to the viability and persistence of many species’ populations worldwide. The use of translocations as a viable conservation tool in conjunction with protected areas has been rapidly increasing over the last few decades. Protected areas such as strict nature reserves, national parks, and species management areas continue to be central tools for biodiversity conservation as they provide vital habitats set aside from various human pressures. Because action consistently runs ahead of policy, the need for a clearer evidence base on the outcomes of wildlife translocations undertaken at a global scale is becoming increasingly urgent for scientific and decision-making communities, in order to build clear strategy frameworks around conservation translocations. We therefore conducted a systematic mapping exercise to provide an overview of the existing evidence on the outcomes of wildlife translocations in protected areas.

Methods

We searched two bibliographic databases, four web-based search engines with search-by-key-words capacity, 5 specialist websites, and conducted a grey literature call through two project stakeholders. We screened articles by title, abstract, and full text using pre-defined inclusion criteria all the while assessing the consistency of the reviewers. All relevant translocations were coded from retained publications. Key variables of interest were extracted and coded for each translocation event. The quantity and characteristics of the available evidence and knowledge gaps/clusters are summarised. The distribution and frequency of translocations are presented in heat- and geographical maps.

Review findings

A total of 613 articles were considered eligible for coding bibliometric data. Metapopulation management and review articles were not coded for quantitative and qualitative variables. Linked data (duplicated translocations) were also excluded. Finally, 841 studies of different translocation events were fully coded from 498 articles. Most of these translocations were carried out in North America and Oceania. The most commonly undertaken intervention types were one-off supplementations and “supplemented reintroductions”. Mammals were by far the most transferred group among animals. Magnoliopsida was the most translocated plant group. Survival, space use, and demography metrics were the most studied outcomes on translocated species.

Conclusions

This systematic map provides an up-to-date global catalogue of the available evidence on wildlife translocations to, from, or within protected areas. It should enable protected area managers to better understand their role in the global network of protected areas, regarding translocation practice, both as suppliers or recipients of translocated species. It may help managers and practitioners make their own choices by comparing previous experiences, regarding both the species concerned and the precise translocation modalities (number of individuals, etc.). Finally, it constitutes a decision-making tool for managers as well as for policy makers for future translocations.