Combining climate, land use change and dispersal to predict the distribution of endangered species with limited vagility

Aim: Many rare species are dispersal-limited; their colonization capacity can be impacted by land use and climate changes. Most ecological niche models predict the distribution of species under future climate and land use change scenarios without incorporating species-specific dispersal abilities. Here we investigate the effect of climate and land use change on low vagile species accounting for their dispersal capacity and define accessible areas in the future. Location: Europe. Taxon: Saproxylic beetles. Methods: We used the current (2007–2012) occurrences of six endangered saproxylics to develop ecological niche models using current climate and land use conditions. We projected species distributions under four future climate and land use change scenarios to estimate their potential occurrences. Finally, accounting for species-specific dispersal, we limited their distributions to accessible areas in 2040–2050. Results: Without accounting for dispersal abilities we found a strong and positive impact of climate change on the distribution of Cerambix cerdo, Cucujus cinnaberinus, Morimus funereus and Rosalia alpina and a positive effect of land use change on the distribution of Lucanus cervus and Osmoderma eremita. When species-specific dispersal was included, we found a strong and positive impact of land use change on the distribution of all the species. In this case climate change had a lower but positive effect on the distribution of C. cerdo, C. cinnaberinus, L. cervus and R. alpina, and a negative effect on the distribution of O. eremita. Main conclusion: We found that climate change would promote the expansion of saproxylic beetles only in the unrealistic case of unlimited dispersal. Accounting for dispersal abilities, the expansion of our species would be mainly conditioned by the effect of land use change. Thus, we encourage researchers to combine climate and land use change with dispersal when projecting species distribution under future scenarios to accurately identify areas with fundamental species-specific resources.