Assessment of Tree Species (Cupressus lusitanica and Pinus patula) Debarking by Monkeys in Cerengoni Forest-Block Ecosystem in Nandi County, Kenya


  • Ms. Barbara Mong’ina PG Student, Conservation Biology, University of Eastern Africa Baraton, P.O.BOX. 2500-30100 Eldoret, Kenya
  • Prof. Benard Muok Director, Centre for Research, Innovation and Partnerships at Jaramogi Oginga Odinga University of Science and Technology. P.O. Box 210 - 40601 Bondo, Kenya.


Debarking, Monkey, Cupressus lusitanica, Pinus patula


Monkeys strip the bark off the trees to feed on underlying vascular tissues, leading to
the death of trees causing the destruction of the habitat. The main objective of this study was
to elucidate information and knowledge of debarking by wild animals and their effect on the
forest ecosystem in Cerengoni forest in Nandi County, Kenya. This study was conducted in
Cerengoni forest, Northern Tinderet part, which is 12,578 Ha located between Latitude 00 3”
and Longitude 350 25” of Nandi County, Rift Valley Kenya. The study area is covered by
45.9 Ha of Cupressus lusitanica and 47.8 Ha Pinus patula plantations. The study employed a
systematic survey, descriptive designs, and experimental designs. A random sampling
technique was used where a troop population of monkeys was established, as they were
crossing the observation paths. Fieldwork commenced in February 2021, and continued till
May 2021. Three days a week, three weeks a month was average days spent on the forest
compartments during this period. The Kenya Foresters assistants located monkeys by use of
GPS and visual and auditory cues, a form of method used by the endemic people who
habituate in this forest to locate primates in this forest. Data (type, height and age of
debarking) from the two compartments involved was collected. Descriptive statistics were
used to analyze the extent of Cupressus lusitanica and Pinus patula damage as a result of
debarking. Frequencies and percentages were tabulated to describe the debarking of the trees
based on type, height and age. A total of 73% of the sampled trees were debarked by
monkeys. The monkey species that debark Pinus patula and Cupressus lusitanica in
Cerengoni Forest are the vervet, and sykes monkeys. The study found out that there is no
recorded data on tree debarking in Cerengoni forest station. The study recommended that a
routine survey be conducted and data kept on the monkey debarking. This will help to obtain
financial losses experienced due to monkey debarking.


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How to Cite

Ms. Barbara Mong’ina, & Prof. Benard Muok. (2021). Assessment of Tree Species (Cupressus lusitanica and Pinus patula) Debarking by Monkeys in Cerengoni Forest-Block Ecosystem in Nandi County, Kenya. International Journal of Sciences: Basic and Applied Research (IJSBAR), 60(4), 249–266. Retrieved from