Longer-term ecosystem level dynamics are often neglected in conservation studies involving single species. In this study, a retrospective analysis is presented on the feeding performance of African wild dogs Lycaon pictus in the Serengeti in relation to a competing species, the spotted hyena Crocuta crocuta, to test whether hyenas had an effect on feeding performance of wild dogs in this ecosystem. Our analysis is based on observations of over 700 wild dog kills recorded over a 20-year period (from 1964 to 1987) during which time there was a decline in wild dog numbers (ending with their local extinction in 1991) and a twofold increase in hyena density. Overall, the amount of time that dogs had access to the kill (access time) decreased with increasing numbers of hyenas attending kills, but access time increased with increasing hunting-group size of dogs and carcass mass. In addition, in the 1980s, dogs spent longer at kills than in the 1970s for a given set of conditions, including when hyenas were absent. Our analysis demonstrates a greater potential for group benefits than was found in a previous study (Carbone, Du Toit et al., 1997). Hunting-group sizes of between two and six dogs performed best when hyenas attended dog kills because the benefits of increased defence outweighed the costs of having to share the carcass with more dogs. Hunting-group sizes of wild dog and levels of hyena attendance at the kill broadly paralleled the population trends in these species, with hunting-group sizes of wild dog declining, followed by hyena attendance increasing. Despite the combined effects of increased hyena attendance and reduced hunting-group size, dogs in the 1980s typically spent longer feeding and consumed more of the carcass including the poorest sections. This suggests that dogs in the 1980s may have been under greater energetic stress.

Abstract... African wild dogs were studied ilrcm 1967 ru 1978 or, tile Ser$:ngeti Plains in northern ianzania. The mzin ubjectives werc to dererinine the status ci t1:e sub-population and ro elucidate the eiology and behavior of this social carnivore. Thi: paper describes the decline of the sub-pcpulation, the dynamics of pack composition, and pncterns of dispersal.

This paper presents a synopsis of the current status and distribution of the African wild dog Lycaon pictus, outlines reasons for its decline and discusses recommendations to halt or reverse this decline. A recent review of the status of the species provides evidence that it has disappeared or is in decline throughout its range (sub-Saharan Africa). Relict populations with little or no chance of long-term survival are found in several countries including Algeria and Senegal. Countries believed to contain potentially viable populations are, from north to south, Kenya, Tanzania, Zambia, Zimbabwe, Botswana, and South Africa (only the Kruger National Park).