The impacts of management interventions on the sociality of African lions (Panthera leo): implications for lion conservation.
African lion (Panthera leo) populations normally consist of several neighbouring prides and multiple adult males or groups of males that interact competitively. In large, open systems, cub defence from infanticidal males and territory defence drive group living in lions. However, in smaller (<1000 km2), fenced wildlife reserves, opportunities for natural immigration and emigration are limited which means that the evolutionary drivers of lion sociality may collapse. Here, we use lion behavioural data collected from 16 wildlife reserves across South Africa to test how management-induced ecological conditions alter lion social dynamics. The number of lionesses observed together was best predicted by pride size, prey biomass and biome. Lionesses were less likely to group together as pride size increased, but more likely to group together as prey biomass and habitat productivity increased. In addition, adult males were observed more frequently with prides that had young (<12 months) cubs in reserves that had unfamiliar adult males present compared to reserves without any unfamiliar adult males. Our results demonstrate how intraspecific competition between lions drives their sociality, and this may break down in small, fenced wildlife reserves where lions are actively managed. Although small, fenced reserves in South Africa have made a significant contribution to increasing lion numbers on the continent, our work highlights several important ecological implications of active lion management. For wildlife managers, mimicking the outcomes of different levels of intraspecific competition is likely a critical management tool for the persistence of lions in small reserves.