Monkeying Around: Spatial Differences in Riverine Habitat Utilization by Vervets, Sykes, and Baboons

The purpose of this study was to examine where in five vertical locations (river, bank, ground, trunk, and canopy) and at what times vervet monkeys, sykes monkeys and baboons utilized the habitat of the Simba River at Ndarakwai Ranch in the West Kilimanjaro district of Northern Tanzania. The study attempted to use this information, particularly in regards to eating behavior, to see if these sympatric species use vertical special or time of day to partition the resources along the river, and if close proximity to other primates affected vertical location. The study was conducted within 25m of a 2.8km section of the Simba River between April 11 and April 29, 2009. Groups of primates were encountered during walking transects of the river and data points containing species, time, location, and behavior of each individual were collected using scans. Data points (n=3279) were analyzed using descriptive statistics. Results indicated that primates do utilize different vertical levels of the habitat with sykes remaining predominantly in the canopy, baboons on the ground, and vervets utilizing both substantially, but spending more time on the ground. Differences by time of day were slight. Eating behavior by vertical level followed the overall trend. When grouped with other primates, sykes and baboons did not greatly change their location, but vervets moved to the ground in the presence of sykes and to the canopy in response to baboons. Overall, the hypothesis that these primates use different vertical levels to share the habitat was supported by the study and emphasizes the need to conserve all parts of the habitat (as opposed to focusing on fruit trees) for wildlife management