Driver interactions lead changes in the distribution of imperiled terrestrial carnivores

Abstract

Biodiversity is dramatically declining worldwide due to the complex processes that include interactions among threats. Studies investigating how multiple drivers (inter)act to influence spatio-temporal shifts in species distribution ranges, which are among the most anticipated changes in biodiversity in the future, are still scarce in the scientific literature, particularly at meaningful conservation planning scales. We used species occurrence data for eight terrestrial Mediterranean carnivores at a regional scale of southern Spain to: 1) estimate environmental favourability to each species during two periods (1960s and present); 2) predict current favourability assuming the same environment-species relationships as the ones observed in the 1960s (expected favourability); and 3) analyse single and interactive effects of human persecution, presence of protected areas, and prey richness on favourability changes (present vs. expected) for each carnivore species. We found that, with a few exceptions, environmentally favourable areas for carnivore occurrence were more widely distributed in the past than today and, for most species, favourability tended to increase inside protected areas, with low frequency of poisoning events and high prey richness. Notwithstanding, for rare species such as Iberian grey wolf (Canis lupus signatus) and Iberian lynx (Lynx pardinus), interactions among drivers were the most important predictors of favourability changes, underpinned by a compensatory role of protected areas in the face of continued human persecution. We emphasize the role of protected areas in abating the effects of biodiversity threats and claim that scientific studies based on analyses of single-effect drivers that omit driver interactions may misinform conservation planning and require revision.