Movement, Feeding Behaviour and Threats of Colobus guereza Ruppellin at Seasonally Dry Riverine Forest of Engare-Olmotonyi and Arboreta of the Forestry Training Institute’s Olmotonyi’s Campus in Northern Highlands of Tanzania

Abstract

The observation of feeding and movement behaviour of wild fauna is significant in the process of understanding the ecosystems. The movement and feeding behaviour of An assessment on the movement, feeding behaviour, and threats of Colobus guereza was done in Engare-olmotonyi seasonally dry riverine forest and arboreta at the Forestry Training Institutes-Olmotonyi in northern Tanzania. The movement and feeding behaviour were monitored for 30 days from mid of September to October 2020. Sleeping and waking up times, trees fed by C. guereza, and trees they slept on were recorded and estimated for their height and canopy cover (light or dense). The human threats were also recorded. The findings revealed that C. Guereza members were waking up between 6.30 am and 6.58 am, depending on the condition of the sky (clear or cloudy). When the sky was clear they wake up between 6.30 and 6.45 am, and 6.45 am to 6.58 am on cloudy sky days. They slept on the highest canopy trees and were feeding on tender or mature leaves depending on the type of species. The flowers and fruits of Jacaranda mimosifolia, Albizia gummifera (J.F.Gmel.) C.A.Sm., Cussonia holstii Harms ex Engl and leaves of Lagenaria abyssinica (Hook.fil.) C.Jeffrey were found to be fed by C. guereza. As soon as they wake up, they both of them urinated. Then, young C. guereza were found to be directed to move before adults just after they had urinated. The height of trees the C. guereza were found to jump on and or sleep ranged from 24 ± 10 m, with an average height of 17 m. The tallest trees ranged from a height of 24 ± 20 m; while the medium had a height of ≤ 20 ± ≤15 m. Most of the tallest trees were Albizia gummifera (J.F.Gmel.) C.A.Sm., Jacaranda mimosifolia D.Don; Cussonia holstii Harms ex Engl.; and Eucalptys maidenii F. Muell. The threats to C. guereza were cutting of trees as their food and habitat and illegal routes that disturbed their behaviour of feeding and movement. The direction of C. guereza movements and sleeping depend most on the trees.  Further study is needed to evaluate the plant species being fed at different seasons, protect the existing trees, and restore the forest gaps.