Although the leopard (Panthera pardus) is one of the more successful large carnivores, challenges for leopard conservation emulate those of other more endangered carnivores, and they are a model species for investigating issues affecting carnivore persistence worldwide. This thesis represents a six year study of leopard on the Karongwe Game Reserve, South Africa, which provided a unique opportunity to observe various aspects of behavioural ecology in the absence of prey availability constraints or human persecution. Small, enclosed reserves such as Karongwe make up 16.8% of the total land in South Africa and undertaking sound ecological research in these areas provides valuable data for evidence-based conservation and management. The leopard is notoriously shy and difficult to study and I used free darting and habituation to enhance visual observation, in order to understand the ecological processes influencing leopard reproductive success and survival. My results show that leopard in the high prey area studied, consume almost double the number of ungulates as leopard in similar habitats elsewhere. This generalist predator improved its hunting success by selecting vulnerable prey and selectively hunted in habitats of intermediate density, where preferred prey were most abundant. Ample nutrition played a key role in reproductive health and reduced the duration of reproductive parameters below that previously recorded in the literature. Any additional nutritional input could not translate into increased population growth as females were already reproducing optimally. Female territorial size and habitat selection were determined by the availability of riparian habitat and resources of their preferred prey. Territoriality however was governed by prey biomass. Neighbouring leopards were territorial, sharing little space (average 11% territorial overlap) and hunting five times more often in the core than in the rest of their territory. During periods of prey richness, females became more territorial and there was a positive “bottom up” effect through subadult recruitment. Density-dependent intraspecific and interspecific competition for limited space regulated the population around carrying capacity, and constrained population growth. These results provide fundamental baseline data about leopard in the absence of human disturbance, or prey constraints. They highlight that, although the influence of optimal nutrition is important in the reproductive health and territoriality of leopard, habitat quality and quantity are ultimately what govern leopard carrying capacity and population size. I provide baseline reproductive, carrying capacity and territorial data for agencies developing policy, and for setting priorities in conservation and management, as well as habitat protection and restoration, for not only this species but other threatened species as well. / Thesis (Ph.D.)-University of KwaZulu-Natal, Westville, 2013.