Existing evidence on the outcomes of wildlife translocations in protected areas: a systematic map


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.


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.


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.


Managed relocations, Reintroduction, Reinforcement, Supplementation, Ecological replacements, Assisted migration, Rewilding, Conservation areas


Conversion, fragmentation, and loss of natural habitats are among the main causes of declining species’ populations worldwide. Protected areas are therefore crucial for biodiversity as they provide refuge and ensure key ecological processes. Wildlife translocations, defined as “the deliberate movement of organisms from one site for release in another”, have been used in conjunction as a conservation tool for a number of decades as wild populations become increasingly fragmented and endangered. Not only are translocations used to bolster the viability of imperiled species but are also recommended for improving population resilience and adapting species’ ranges in response to climate change. Despite translocation being a recognised conservation tool, it remains complex with variable results due to the different factors that can determine its success. Accordingly, the Map will investigate the existing evidence on the links between different types of wildlife translocation interventions and factors that may be important to consider for planning. This will provide an overview of relevant studies for possible future syntheses, and may help to inform management decisions.


We will perform a thorough search of peer-reviewed journal articles and grey literature sources documenting the occurrence of translocations in the context of protected areas. Two databases will be used: Web of science core collection and Scopus, with a supplementary search in Google Scholar. Multiple key specialized websites will also be used. All bibliographic data will be extracted, managed, and screened in Microsoft excel. Three screening stages will be undertaken (title, then abstract, then full texts) against predefined inclusion criteria. The retained relevant literature will be subjected to coding and meta-data extraction. No formal validity appraisal will be undertaken. The Map will particularly highlight translocation operations in terms of origin and destination (i.e. translocating from one protected area to another, within the same area, and from and to non-protected areas) by taxonomic group, among other important factors (e.g. number of individuals, age class, release strategy, distance between capture and release sites etc.). Finally, a database will be provided along with a Map narratively describing the evidence with summary figures and tables of pertinent study characteristics.