"Interspecific Competition Among Cercopithecus campbelli, Cercopithecus petaurista, and Cercopithecus diana at Tai Forest, Cote d'Ivoire" by Paul Jason Buzzard

Paul Jason Buzzard

Deposited 2004

Abstract
Ecological relationships between similarly adapted species are often characterized by competition, although other factors such as predation and habitat disturbance may at times play a larger role than interspecific competition in structuring those relationships. This study investigated the role interspecific competition played in the relationships among Cercopithecus campbelli , C. petaurista, and C. diana in the Taï Forest, Côte d'Ivoire.

To measure competition, I assessed population densities and social systems. I also measured ecological partitioning in and out of association, ranging patterns, agonistic rates and cheek pouch use in relation to food availability.

C. diana was competitively superior to the other species. C. campbelli was more affected by competition with C. diana than was C. petaurista. Each species was at a similar group density but C. diana formed larger groups. C. petaurista diverged from the other species primarily by consuming more foliage while C. diana and C. campbelli mostly ate fruit and differed from each other primarily in the canopy strata used, with C. diana using higher strata than C. campbelli . C. diana/C. campbelli overlapped the most in food items and diverged the most in the season of fruit scarcity. C. diana/C. campbelli age/sex classes also overlapped the most of any species pair. The study species spent 60–90% of their time in association with each other. Niche shifts in association were not great and association was not related to fruit availability. Ranging patterns were very similar and did not change in relation to food availability or fruit consumption. C. campbelli received the most aggression from C. diana and C. campbelli used cheek pouches the most overall and in the season with the most aggression. Cheek pouch use was not positively related, however, to association with C. diana.

The results indicated that competition was less important among the study species than for other guenon communities. A high predator risk was demonstrated in this community, and I discuss the importance of predator risk and adaptations to reduce predation as structuring factors in this community.