Dietary niche relationships among predators on farmland and a protected area

Abstract

ABSTRACTThe use of land for pastoralism is often associated with a reduction in the diversity and abundance of wildlife and influences conflict between farmers and predators worldwide. We explored differences in the diversity and relative abundance of medium and large animals on farmlands and a nearby protected area and compared these differences to prey consumed by 3 sympatric predators (black‐backed jackal [Canis mesomelas], caracal [Caracal caracal], and leopard [Panthera pardus]) in the Karoo region of South Africa. All 3 predators, but especially jackals and caracals, are a source of conflict with small‐stock farmers, many of whom believe that predators use the protected area as a base for raiding farmland. We determined predator diets using 657 scats collected on both land uses in subsequent years. Domestic ungulates dominated the farming landscape and comprised the bulk of prey in the scats of jackals and caracals as determined by the frequency of occurrence (42% and 25%, respectively), percent volume (47% and 32%, respectively), and ingested biomass. By contrast jackals and caracals in the reserve fed primarily on fruits and micromammals, respectively, with a lower ingested biomass of mammalian prey. No domestic sheep were in any of the scats in the reserve. We found leopard scats only in the reserve and they mostly contained wild ungulates. Dietary niche breadth and overlap were higher on farms than in the reserve and were attributed to the high consumption of domestic livestock by jackal and caracal. Dietary overlap between medium‐sized predators and leopards was small. Caracals on farms and caracals and jackals in the reserve showed strong prey preference for wild mammals, whereas jackals on farms showed prey preference for goats and sheep over similar‐sized wild mammals. Leopards showed preference for bushpig (Potamochoerus larvatus) and mountain‐dwelling antelopes but consumed baboons (Papio ursinus) according to availability. Together these results fill a gap in our knowledge about jackal and caracal diets on farmland and dietary niche relationships between 3 sympatric predators in conflict with small‐stock farmers in the semi‐arid regions of South Africa. In terms of management, our results show that it is crucial that farmers protect their livestock from predators, even on farms where wild prey are abundant because of jackals' preference for sheep and goats over similar‐sized wild mammals. © 2017 The Wildlife Society.