Do spotted hyaenas outcompete the big cats in a small, enclosed system in South Africa?

Abstract

Carnivores are adapted to kill, meaning sympatric carnivores can have particularly aggressive and harmful competitive interactions. The co-existence of multiple carni-vores in an ecosystem could be restricted by their similarity in ecological niches(e.g. dietary overlap); however, high prey abundances could facilitate their co-exis-tence. Although the development of small, enclosed reserves (<400 km2) in South Africa has reduced human–carnivore conflict, these systems may increase the likeli-hood of carnivore intra-guild competition due to the clumping of competing carni-vores into these restricted spaces. Using carnivore scat and kill site analyses, we determined the dietary preferences and overlap of sympatric large carnivores in a small, enclosed reserve, Selati Game Reserve (Selati). Large carnivores in Selati (lions (Panthera leo), spotted hyaenas (Crocuta crocuta) and leopards (Pantherapardus)) preferentially selected for varying combinations of prey size classes. Lions selected for large prey, leopards selected for small prey and spotted hyaenas did not prefer any particular prey size. Additionally, lions had the largest dietary breadth and the diet of leopards and spotted hyaenas overlapped considerably. Cou-pled with high prey densities in Selati, the predation strategies of the large carni-vores could be facilitating their co-existence. On the other hand, the high degree of dietary overlap among large carnivores suggests that there is strong potential for exploitation competition, particularly between spotted hyaenas and leopards as their diet overlapped extensively (91% and 93% for prey species and size class, respec-tively). Although spotted hyaenas are potentially outcompeting leopards in Selati,lions were the most dominant large carnivore. Our study reiterates the complexity of carnivore guild interactions and emphasizes how these interactions are subject tovariation due to site-specific circumstances (e.g. composition of prey and carnivore populations). We therefore encourage site-specific, multi-carnivore research throughout protected areas in southern Africa.