Due to high levels of exploitation, habitat loss and habitat degradation, Pan troglodytes has experienced such a significant population reduction over the past 20 to 30 years that it is now on the IUCN (International Union for the Conservation of Nature and Natural Resources) Red List of Endangered Species. The Nigerian chimpanzee, Pan troglodytes ellioti (Gray 1862), is the most endangered of the four subspecies of chimpanzee. It has the smallest distribution and smallest population size, estimated in 2011 to be between 3,500 – 9,000 individuals. P. t. ellioti was first recognized as a distinct subspecies in 1997, and in 2008 an Action Plan Study Group was set up with the goal to determine the priority sites for its conservation and the actions that should be taken to ensure its long-term survival. The Action Plan was published in 2011 and this thesis is timely as it begins to answer some of the questions deemed important in the action plan. The overall aim of this study was to explore the ecology and behaviour of a small, isolated montane population of P. t. ellioti with the aim of making a useful contribution to future recommendations for the management and conservation of this subspecies. Specifically, I estimated the density of chimpanzees in Ngel Nyaki Forest Reserve, Taraba State, Nigeria and investigated their nesting ecology, elementary technology, diet, seed dispersal and the viability of seeds dispersed by the chimpanzees. I estimated chimpanzee density by using a combination of direct (direct observation) and indirect methods using nest counts. My investigation of nesting ecology concentrated on identifying habitat variables that influenced choice of nesting site. I assessed elementary technology by locating and describing both manufactured artefacts and unmanufactured objects, and I then located evidence from the surrounding environment to establish details about their presence or absence. Chimpanzee diet was assessed using evidence from faecal samples and artefacts. In order to identify preferences and agents involved in removal of various seed species ingested and dispersed by chimpanzees I set-up a series of experiments using plots into which seed piles were added. Lastly, I compared the rate of germination of conspecific seeds which had been passed through a chimpanzee gut with those that had not been dispersed.

The goal of this study was to examine several aspects of the population genetics and population biology of the Nigeria-Cameroon chimpanzee at seven sampling locations in the south of Taraba State, Nigeria. Three of the sampling locations are within GGNP and two are situated just outside the southern boundary of GGNP. The final two sampling locations are found within Ngel Nyaki forest reserve, at each of the two forest fragments inside the reserve. Ngel Nyaki forest reserve was the focus of the study and the principal goal was to 16 determine if the community of chimpanzees at Ngel Nyaki forest reserve has become isolated from the chimpanzees at GGNP using microsatellite loci extracted from non-invasive sources of DNA. In Chapter two, the methods used to extract and amplify the DNA and the protocols used to confirm the genotypes are outlined. Chapter three examines the population structure of the chimpanzees among the regions sampled in this study, particularly addressing the question as to whether the chimpanzees at Ngel Nyaki forest reserve are isolated from the chimpanzees at GGNP. Chapter four investigates patterns of sex biased dispersal in the Nigeria-Cameroon chimpanzee. In Chapter five, population viability analysis is used to determine the fate of the chimpanzees at Ngel Nyaki forest reserve under a range of management scenarios. Chapter six summarizes the conclusions of the study and presents a conservation strategy to ensure the viability of the population of chimpanzees at Ngel Nyaki forest reserve.