The effects of habitat features and prey density on the hunting and scavenging success of Serengeti lions (Panthera leo)

This thesis addresses the question of whether Serengeti lions choose foraging sites that facilitate the capture of prey, or whether they choose foraging sites where prey are most abundant. The alternate choices between good habitats and high prey densities have rarely been addressed in resource selection studies of predators. The observed distributions of kills and scavenges by lions were compared to the predictions of two alternate hypotheses; (a) if lions forage in areas that facilitate the capture of prey, such as areas with cover, then more kills and scavenges should occur in these areas than expected. Conversely, (b) if lions forage in areas with high prey densities, and prey avoid risky habitats, then most of kills and scavenges should occur in areas with reduced cover. The hypotheses were tested by comparing the use and availability to lions of 5 habitat types: viewsheds from kopjes, river confluences, erosion embankments, woody vegetation, and sites with access to free water. The amount of each habitat type available was estimated from maps created by GIS analyses and ground truthing, and were tested with univariate, goodness of fit, exact tests as well as multivariate resource selection functions. The results indicate that on the large scale lions move according to the distribution of prey. However, at a finer scale lions select areas that facilitate foraging over areas with high prey densities. Plains and woodland lions selected different habitats depending on season. However, the most important habitats that were selected by both plains and woodland lions for either hunting or scavenging were, river confluences, eroded areas, and areas with water nearby. Viewsheds from kopjes and areas with woody vegetation were also selected, but were not as important. Furthermore, areas with vegetation associated with confluences, vegetation associated with water, and eroded sites associated with water were preferred for foraging more often than predicted. Therefore, the major finding from this study is that although lions require adequate prey for survival, the habitat features available to them for hunting and scavenging are more important than simple prey densities.Science, Faculty ofZoology, Department ofGraduat