Hierarchy of fear: experimentally testing ungulate reactions to lion, African wild dog and cheetah

Experiments have begun demonstrating that the fear (antipredator responses) large carnivores inspire in ungulates can shape ecosystem structure and function. Most such experiments have focused on the impacts of either just one large carnivore, or all as a whole, rather than the different impacts different large carnivores may have in intact multi-predator-prey systems. Experimentally testing the relative fearfulness ungulates demonstrate toward different large carnivores is a necessary first step in addressing these likely differing impacts. We tested the fearfulness ungulates demonstrated to audio playbacks of lions (Panthera leo), African wild dogs (Lycaon pictus), cheetahs (Acinonyx jubatus) or non-predator controls (birds), in Greater Kruger National Park, South Africa. Ungulates ran more to lions than wild dogs and more to wild dogs than cheetahs, demonstrating a very clear hierarchy of fear. Those that did not run were vigilant (looked toward the sound) more upon hearing large carnivores than controls, being most vigilant to lions. Notably, predator prey preferences did not predict the patterns observed. Our results demonstrate that different large carnivores inspire different levels of fear in their ungulate prey, pointing to differing community-level impacts, which we discuss in relation to the ongoing worldwide decline and loss of large carnivores.