Reintroduction biology and the IUCN Red List: The dominance of species of Least Concern in the peer-reviewed literature

Reintroduction biology is a key tool for mitigating the catastrophic reduction in species’ ranges, caused by humans over the last 500 years. To assess where reintroduction biology scientific research is targeted, we used text-analysis methods to extract taxonomic and geographic mentions from animal reintroduction-focused articles published between 1990 and 2022 (n = 2061). We then related our results to the IUCN's Red List and countries’ GDPs. We found most articles were targeted towards species of ‘Least Concern’, many of which are considered charismatic and/or restore important ecosystem functions. Countries with a higher GDP had a decreased relative proportion of research on imperilled species, with Australia and New Zealand being notable exceptions. The knowledge gained from long-term, well-funded charismatic species (e.g., wolves) has been an important contribution to reintroduction biology, providing vital knowledge that informs reintroductions of other, more threatened, species. In the context of attempting to continue to expand scientific knowledge to an increasing array of threatened species, it is important to acknowledge that some aspects of our knowledge base may be largely derived from a relatively small number of well-studied species. Research focused on reintroductions and restorations of functionally important, but less charismatic, species would be an important contribution to the reintroduction biology knowledge base.