Prey apportionment and related ecological relationships between large carnivores in Kruger National Park

Abstract

Abstract Of the five large carnivores in the Kruger National Park, spotted hyaenas have the widest diet, eating more non-mammal food items than the others. They also scavenge more than the others, about half the biomass of food they consume. The diets of lions, leopards, cheetahs and African wild dogs overlap strikingly with regard to medium-sized and small mammals, particularly impala. Lions removed over 50% of the biomass of prey killed by the large predators in the main study area, having a particularly heavy influence on the wildebeest population. They may also deprive the smaller predators of impala. Hyaenas scavenged a substantial amount of food from lions, but only after the lions had finished eating. Hyaenas chased cheetahs off 14% of their kills, but were not seen to steal food from wild dogs. Lions were observed to kill wild dogs. Hyaenas and lions showed a preference for thickets and plains, leopards for thickets, hills and river banks, cheetahs for plains and wild dogs for thickets and hills. Impala had their highest preference ratio for thickets, followed by hills and plains. Hyaenas, lions and leopards are predominantly nocturnal, wild dogs are crepuscular and cheetahs kill mainly during the middle of the day. The large number of resident prey in the system favours lions and hyaenas. Leopards, with a wide diet and the ability to utilize habitats not favoured by most of the others, outnumber cheetahs and wild dogs. Cheetahs have to cope with sub optimal hunting conditions and pressure from spotted hyaenas. It is unclear why wild dogs, which are such efficient hunters in this area, are not more abundant.