Activity and ranging patterns of guerezas in the Kakamega Forest: Intergroup variation and implications for intragroup feeding competition

From March 1997 to Feburary 1998, I investigated the activity patterns of 2 groups find the ranging patterns of 5 groups of eastern black-and-white co lobus (Colobus guereza), aka guerezas, in the Kahamega Forest, Kenya. Guere zas at Kakamega spent more of their time resting than any other population of colobine monkeys studied to date. In addition, I recorded not one instan ce of intragroup aggression in 16,710 activity scan samples, providing prel iminary evidence that intragroup contest competition may be rare or absent among guerezas at Kakamega. Mean daily path lengths ranged from 450 to 734 m, and home range area ranged from 12 to 20 ha though home range area may h ave been underestimated for several of the study groups. Home range overlap was extensive with 49-83% of each group's range overlapped by the ranges o f other groups Despite the high level of home range overlap, the frequently entered areas (quadrats entered on greater than or equal to 30% of a group 's total study days) of any one group were not frequently entered by any ot her study group. Mean daily path length is not significantly correlated wit h levels of availability or consumption of any plant part item. Mean daily path length is also not significantly correlated with group sire, though th e largest group did have the longest mean daily path length. This finding s uggests that intra-group scramble competition may have been rare or absent among guerezas at Kakamega except perhaps in the largest group, which was u nusually large.