Joanna Z. Greenfield, BSc thesis 1988.

The aim of this study was to examine the interrelations and interactions of four primate species, Cercopithecus  ascanius (Red tail monkey),  Cercopithecus mitis (Blue monkey), Cercopithecus  l’ Hoesti  (I’ Hoest's monkey),  and Pan troglodytes (Chimpanzee)  in the Bwindi Impenetrable Forest in Uganda. These relationships were analyzed using niche separation and overlap in vertical foraging, food species, and interspecific behavioural interactions. 

Foraging heights were recorded to reveal the pattern of vertical niche differentiation.  Food eaten was also recorded so that a comparison of food preferences could be made. Additional information on interspecific dominance and poly-specific associations  was recorded opportunistically.

The results showed C. ascanius and C. mitis have the highest degree of overlap, and P. troglodytes overlaps with the other three species. C. ascanius foraged over all heights of the forest but focused slightly more on the lower middle layer,  C. mitis foraged mostly around the higher middle layer.  P. troglodytes used the three different layers of the forest and C. l’ Hoesti was found to forage mostly in  the lowest layer and on the ground. The close foraging of these primate species next to each other may reduce predation. Results suggest competition among the four primates especially over Ficus capensis fruits. There is an interspecific dominance hierarchy with P. troglodytes > C. mitis > C. l’ Hoesti > C. ascanius. This agrees with results from Kibale Forest.