Feeding and Ranging ecology of Colobus guereza gallarum in Bale Mountains National Park, Southeast Ethiopia

摘要

Colobus guereza gallarum is one of the subspecies Colobus monkeys (Colobus guereza) that restricted to east of the rift valley occupying the highland ecosystems in south eastern Ethiopia. The study of feeding and ranging ecology of Colobus guereza gallarum was conducted in Bale Mountains National Park, Southeast Ethiopia from February to June 2016. Data were collected using focal animal sampling technique for 10 minutes with 5 minutes interval. When the monkeys are observed feeding, plant parts and species eaten were recorded and marked and identified later. During the observation of focal animals in each troop, locations of troops were recorded using GPS every 10 min until the follow was concluded. Ranging data was carried out by calculating daily movements and estimating home range. To study the habitat characteristics of Colobus guereza gallarum, we established three 50x40m quadrats in randomly selected locations within the home range of the focal groups to provide vegetation composition in the study area. The major feeding consumption of Colobus guereza gallarum was leaves (82%) followed by fruits (14%) and shoots (2%), of the overall diet of 8 plant species during the study period. Barks and flowers were the least consumed food items which account 1% each during the observation time. Colobus guereza gallarum is characterized by a daily range length of 243m. However, no significant difference between the range lengths during the wet and dry seasons (X2=0.205, df=1, p=0.651). A total of 18 plant species were mainly characterizing the home range of Colobus guereza gallarum focal groups in the study area. Colobus guereza gallarum were mainly seen in habitats characterized by forests composed of tall trees. Therefore, special attention should be given to conserve the food plants and animals which reside in it. foraging may be of leaf eating, some population's diets come from multiple sources [9].