Baboons are a well studied primate, with extensive data from numerous long-term field sites from various ecological contexts across Africa. Underrepresented in this sample, however, are woodland/forest population. In this thesis I investigated the diet and movement ecology in a woodland/forest population of yellow baboons (Papio cynocephalus) at the Issa valley of Ugalla, western Tanzania. I begin by describing the diet of Issa baboons using macroscopic faecal analysis. 1 show they selectively exploited the environment according to the availability of fruits, and unlike for their savannah conspecifics, there appeared to be sufficient food alternatives during periods of low fruit availability. Using day path lengths (DPL) 1 examined what factors are important in determining movement of baboons at a continental scale. Using a mixed modelling approach with data from 39 baboon troops form sub-Saharan Africa, I show factors to be important on a continental scale include plant productivity, anthropogenic influence, primate richness and group size. Next, 1 explored the movement ecology of baboons at a local scale in two ways, using baboons at Issa. First I examined the DPL and Path Trajectories (PTs: speed and tortuosity) where I find they moved slower and over shorter distances on warmer days, and slower and more directly when fruit was more abundant. Second I examined patterns of space use within their home ranges (HR). I find sleep site availability and habitat type significantly influence movement within HRs and that the forest habitat is avoided whilst rocky outcrops are preferred. Additionally, I find PTs were predicted by habitat type, with baboons moving faster and straighter through habitats they tended to avoid. Finally, I explored the potential for competition between baboons at Issa with sympatric chimpanzees (Pan troglodytes) by comparing their diet and patterns of habitat use. I show that despite periods of high overlap in fruits consumed, competition between these primates is unlikely to be important due to key dietary differences and differential utilisation of habitat types.

Before this study, the Guinea or Western baboon, Papio papio, was almost unknown in its natural environment. This thesis reports a nineteen-month field study of two troops of P. papio carried out in south-eastern Senegal. The monkeys were followed on foot, and aspects of their feeding, ranging and social behaviour were recorded. The troops were censused whenever possible. Both study groups, and other troops in the area, were found to be unusually large by comparison with other known troops in the genus, and although their age-sex compositions were not exceptional, there was some indication that recruitment into the adult population was low. The activity budgets of both troops were similar, and members of both troops spent more time moving and feeding in the dry season than they did in the wet, when they spent more time in social behaviour. These differences were probably related to seasonal changes in productivity, which were large, since no rain feel in six months of the year. The home range of one of the study troops covered about 45 to 50 square kilometres, while the other troop, whose home range was less well known, ranged over about 18 to 20 square kilometres. There were no seasonal differences in the mean distance travelled per day by either troop, although there was great daily variation about the mean of roughly 8 kilometres. This distance was greater than that travelled by most other troops of baboons, and was ascribed to low productivity in the dry season and large troops in the wet. The troops visited some habitats more frequently than they did others, and moved more slowly through those that they visited frequently than through those that they visited frequently than through those they visited less frequently. In the dry season both troops visited areas in which there was relatively dense shade more frequently than they did areas with little shade. In the wet season they avoided areas in which variability was poor. Sleeping sites were found to have a profound influence on the ranging patterns of the baboons, with usage of the home ranges being inversely proportional to the square of the distance from the nearest sleeping site. The baboons apparently chose to sleep in trees which afforded them protection against predation. The sleeping sites were restricted to places in which there was permanent water. The baboons were largely frugivorous. In this they resembled baboon troops studied in other areas. Their diet changed throughout the year, as various plants fruited or seeded, and was more diverse in the wet season, when a wider variety of foods was available. More than a hundred different food items were known to be eaten, and the number of known food types increased throughout the study. Animals in their diet were mostly invertebrates found beneath boulders, but some vertebrates were also eaten. The social organisation and mating system of these baboons were compared with those of the other baboons, including Theropithecus gelada. It was unlikely that they lived in a society in which adult females were constrained to mate with only one male, as are females in two other species of baboon. Instead, there appeared to be competition for sexual partners, with the formation of consortships between adults during the time of the female’s oestrus. Adult males groomed each other in this species, which is uncommon in baboons with competitive mating, except at times of stress.

Savannah baboons are amongst the most intensively studied taxa of primates, but our understanding of their foraging strategies and diet selection, and the relationship of these to social processes is still rudimentary. These issues were addressed in a 12-month field study of olive baboons (Papio anubis) on the Laikipia plateau in Kenya. Seasonal fluctuations in food availability were closely related to rainfall patterns, with the end of the dry season representing a significant energy bottleneck. The distribution of water and of sleeping sites were the predominant influences on home range use, but certain vegetation zones were occupied preferentially in seasons when food availability within them was high. The influence of rainfall on monthly variation in dietary composition generally mirrored inter-population variation. Phytochemical analysis revealed that simplistic dietary taxonomies can be misleading in the evaluation of diet quality. Food preferences were correlated with nutrient and secondary compound content. The differences between males and females in daily nutrient intakes were smaller than expected on the basis of the great difference in body size; this was partly attributable to the energetic costs of reproduction, and possibly also to greater energetic costs of thermoregulation and lower digestive efficiency in females. A strongly linear dominance hierarchy was found amongst the adult females. Dominance rank was positively correlated with food ingestion rates and daily intakes, but not with time spent feeding or with dietary quality or diversity. In a provisioned group, high-ranking females occupied central positions, while low-ranking females were more peripheral and were supplanted more frequently. In the naturally-foraging group, the intensity of competition was related to the pattern of food distribution, but not to food quality, and was greater in the dry season than in the wet season. The number of neighbours and rates of supplanting were correlated with rank, and evidence was presented that high-rankers monopolised arboreal feeding sites.

No description available.

A thesis submitted to the Faculty of Science, University of the Witwatersrand, Johannesburg, infulfilment of the requirements for the .degree Doctor of Philosophy Johannesburg ' 1989