J. Zool., Lond. (2005) 267, 309–322 C  2005 The Zoological Society of London Printed in the United Kingdom doi:10.1017/S0952836905007508 Prey preferences of the lion (Panthera leo) Matt W. Hayward* and Graham I. H. Kerley Terrestrial Ecology Research Unit, Department of Zoology, Nelson Mandela Metropolitan University, P.O. Box 77000, Port Elizabeth, 6031, Eastern Cape, South Africa (Accepted 7 March 2005) Abstract Lions Panthera leo are generally thought to prey on medium to large ungulates. Knowledge of which species are actually preferred and which are avoided is lacking, however, as is an understanding of why such preference or avoidance may arise. An analysis of 32 studies over 48 different spatial locations or temporal periods throughout the distribution of the lion shows that it preferentially preys upon species within a weight range of 190–550 kg. The most preferred weight of lion prey is 350 kg. The mean mass of significantly preferred prey species is 290 kg and of all preferred species is 201 kg. Gemsbok, buffalo, wildebeest, giraffe and zebra are significantly preferred. Species outside the preferred weight range are generally avoided. Species within the preferred weight range that are not significantly preferred (such as roan, sable and eland) generally have features that reduce predation either morphologically (e.g. sable horns), ecologically (e.g. roan and sable occurring at low density), or behaviourally (e.g. the large herd size and increased vigilance of eland). Warthog are below the preferred weight range yet are taken in accordance with their availability and this is probably due to their sympatry with lion, their relatively slow evasion speed and their lower level of vigilance. Plots of prey preference against prey body mass follows a bell curve with a right skew that, we argue, is caused by collective hunting by lions of larger-bodied prey. Our methods can be used on all large predators and are likely to be useful in assessing competition in sympatric communities of predators, cooperative hunting and predicting predator diets. This will allow us to move beyond descriptive dietary studies to improve our predictive understanding of the mechanisms underlying predator–prey interactions. Key words: buffalo, gemsbok, giraffe, Jacobs’ index, optimal foraging, predation preference, preferred prey weight range, zebra, wildebeest, warthog, lion, Panthera leo INTRODUCTION The strategies of a predator are forged by natural selection to maximize nutrient intake while being tempered by a wide range of ecological constraints, such as prey density and habitat, that differ throughout its geographical distribution (Sunquist & Sunquist, 1997). As long as a predator can increase its survival chances or reproductive success by hunting more efficiently, natural selection will favour efficient, optimally foraging predators (J. R. Krebs, 1978). For lions Panthera leo L. this means preying upon a broad range of medium- and large-sized mammals (Hanby & Bygott, 1991). Yet a review of the literature reveals they commonly take species as small as warthog (e.g. Savuti, Botswana; Viljoen, 1993) and as large as buffalo (e.g. Kafue National Park, Zambia; Mitchell, Shenton & Uys, 1965). Lions also take unusual prey items such as * All correspondence to: M. W. Hayward. E-mail: hayers111@aol.com seals (Bridgeford, 1985), rhinoceroses (W. M. Elliot, 1987; Brain, Forge & Erb, 1999; Matipano, 2004) and elephant (Ruggiero, 1991a). A summary such as this reveals very little about the ecology of the lion, other than its catholic tastes. These dominant prey species may be the only ones present or may be the most abundant. Alternatively, these data may reflect innate preferences by lions. If two species are equally abundant, why is one preferred? To determine how and why a predator selects its prey, cognisance of prey availability is imperative. If a predator kills a species more frequently than expected based on its availability then we can consider it a preferred prey species, while if the predator takes proportionally fewer prey than expected based on availability then it is an avoided prey species. This definition of preference is potentially misleading, as a kill signifies not just prey availability but also its vulnerability (Schaller, 1972). The capture of prey by a predator involves behaviours relating to searching, stalking, attacking and subduing, and the susceptibility of a prey species to a particularly predator relates to the matching of these events (J. P. Elliott, McTaggart Cowan &