Colobus monkey (Colobus guereza) presently registered as Data Lacking Animal on the IUCN Red list does not get conservation care. With the current increasing habitat loss and degradation across its geographic range, data on the activity patterns are essential to design a management plan the data could be to evaluate the UNESCO program under the Man and Biosphere Reserve's objective with respect to colobus monkey conservation. This study, aims at providing data on the activity patterns of two C. guereza groups (Group I and Group II) found respectively in transitional and core zones of Kaffa Biosphere Reserve, Saylem District, South western Ethiopia. Sampling methods for the activity patterns of C. guereza groups was done through field observation using scan sampling for five consecutive days per months in a group. The activity time budgets were studied in two groups for five minutes with fifteen minutes interval scan sampling for six months (January, 2019 to June, 2019). To evaluate the variation of the two-habitat types vegetation studies were conducted by using systematic random sampling. On each transect, five quadrilateral plots of dimensions 20m by 25m (500m2) were systematically established at 100m interval throughout the home range of the two groups. All statistical data were analyzed using R 3.5.2 Programming language software and the chi - square test was used to compare statically significance between the groups and seasons. A total of 34 plant species in 22 families in the home range of Group I, and 46 plant species in 27 families in the home range of Group II were enumerated. There were 293 and 336 individual stems with varying sizes in the respective Groups. The plant species diversity (H’) and evenness (J) in the home ranges of the study groups were 2.80 (0.8) and 3.00 (0.78) for the groups respectively. The overall activity time budgets (n=11861mins) of C. guereza their respective Groups I and II were, 37.67% and 47.60% of their time spent in resting, 29.7% and 12.52% moving, 16.2% and 21.79% feeding, 4.55% and 4.75% playing, 5.70% and 8.13% grooming 2.96% and 2.10% aggression, 0.87% and 1.23% sexual activities and 2.35% and 1.88% was spent on other activities. Even though there were some behavioral activity variations in the groups of C. guereza, the Biosphere’s transition zone can serve as an equivalent habitat for conservation of the monkeys some preferred diet plants are planted in the area in the area.

Keywords: Activity budget, biosphere reserve, Colobus guereza, core conservation zone, Kaffa, Saylem District