International Journal of Primatology

, Volume 31, Issue 3, pp 339–362 | Cite as

Diet, Activity Patterns, and Ranging Ecology of the Bale Monkey (Chlorocebus djamdjamensis) in Odobullu Forest, Ethiopia

  • Addisu MekonnenEmail author
  • Afework Bekele
  • Peter J. Fashing
  • Graham Hemson
  • Anagaw Atickem


Bale monkeys (Chlorocebus djamdjamensis) are little-known primates endemic to the forests of the Bale Massif and Hagere Selam regions of Ethiopia. From August 2007 to May 2008, we conducted the first ever study of the species’ behavior and ecology, focusing in particular on its diet, activity patterns, and ranging ecology in the Odobullu Forest. We studied 2 neighboring groups (group A: 55–60 members; group B: 46–50 members) and conducted behavioral scan samples on the first 2–5 individuals sighted at 15-min intervals. Feeding accounted for 65.7% of the activity budget, followed by moving (14.4%), resting (10.7%), social (7.1%), and other behaviors (2.4%). Overall diet during the study was dominated by young leaves (80.2%), though subjects also ate fruits (9.6%), flowers (3.1%), animal prey (2.3%), shoots (1.5%), stems (1.4%), mature leaves (1.1%), and roots (0.9%). Bale monkeys consumed only 11 plant species; of these, the top 5 species accounted for 94.3% of their diet. The top food item, bamboo (Arundinaria alpina), was responsible for a remarkable 76.7% of their diet, with most (95.2%) of the bamboo consumption consisting of young leaves. Mean daily path length for the study groups was 928 m and mean (100% minimum convex polygon) home range size was 15.2 ha. Though we are cautious in drawing conclusions from only 2 groups, the larger group traveled further per day and occupied a larger home range, patterns suggesting scramble competition may be occurring in Bale monkey groups at Odobullu. The dietary specialization of Bale monkeys on bamboo makes them unique among Chlorocebus spp. and suggests an intriguing ecological convergence with the golden monkeys (Cercopithecus mitis kandti) of Uganda and bamboo lemurs (Hapalemur spp.) of Madagascar. Their narrow ecological niche, limited geographic distribution, and bamboo harvesting by local people for commercial purposes place Bale monkeys at risk of extinction. To ensure the long-term survival of Bale monkeys, appropriate management action should be taken to conserve the species and the bamboo forests upon which it depends.


activity budget bamboo feeding ecology home range quantitative natural history scramble competition 



This research was funded by the Ethiopian Wolf Conservation Programme, Pittsburgh Zoo and PPG Aquarium, and Primate Conservation Inc. FARM-Africa and SOS Sahel Ethiopia provided satellite imagery. We thank the Federal Ethiopian Wildlife Conservation Authority and Oromia Region Wildlife Department for their permission to conduct this research, and Stuart Williams for initiating the project. We also thank Colin Groves, Nga Nguyen, and 2 anonymous reviewers for helpful comments on the manuscript and for providing access to relevant literature. We thank Assefa Hailu of the National Herbarium for identification of plant specimens. We thank Addis Ababa University (Department of Biology), the Ethiopian Wolf Conservation Programme, and Frankfurt Zoological Society for their logistical support of our study. We also thank the following field assistants, camp attendants, and villagers for their help: Mohammed Worko, Omer Hajeleye, Hassen Wole, Issa Hussen, Adem Koye, Kemal Mohammed, and Awol Hule.


  1. Altmann, J. (1974). Observational study of behavior: sampling methods. Behaviour, 49, 227–267.CrossRefPubMedGoogle Scholar
  2. Anapol, F., Turner, T. R., Mott, C. S., & Jolly, C. J. (2005). Comparative postcranial body shape and locomotion in Chlorocebus aethiops and Cercopithecus mitis. American Journal of Physical Anthropology, 127, 231–239.CrossRefPubMedGoogle Scholar
  3. Barrett, A. S. (2005). Foraging ecology of the vervet monkey (Chlorocebus aethiops) in mixed Lowveld Bushveld and Sour Lowveld Bushveld of the Blydeberg Conservancy, Northern Province, South Africa. Ph.D. thesis. University of South Africa, Pretoria.Google Scholar
  4. Brugiere, D., Gautier, J., Moungazi, A., & Gautier-Hion, A. (2002). Primate diet and biomass in relation to vegetation composition and fruiting phenology in a rainforest in Gabon. International Journal of Primatology, 23, 999–1024.CrossRefGoogle Scholar
  5. Butynski, T. M. (1990). Comparative ecology of blue monkeys (Cercopithecus mitis) in high- and low-density subpopulations. Ecological Monographs, 60, 1–26.CrossRefGoogle Scholar
  6. Buzzard, P. J. (2004). Interspecific competition among Cercopithecus campbelli, C. petaurista, and C. diana at Tai Forest, Cote d'Ivoire. Ph.D. thesis. Columbia University, New York.Google Scholar
  7. Buzzard, P. J. (2006a). Ecological partitioning of Cercopithecus campbelli, C. petaurista, and C. diana in the Tai Forest. International Journal of Primatology, 27, 529–558.CrossRefGoogle Scholar
  8. Buzzard, P. J. (2006b). Ranging patterns in relation to seasonality and frugivory among Cercopithecus campbelli, C. petaurista, and C. diana in the Tai Forest. International Journal of Primatology, 27, 559–573.CrossRefGoogle Scholar
  9. Caro, T. (1998). Behavioral ecology and conservation biology. New York: Oxford University Press.Google Scholar
  10. Caro, T. (2007). Behavior and conservation: a bridge too far? Trends in Ecology & Evolution, 22, 394–400.CrossRefGoogle Scholar
  11. Carpaneto, G. M., & Gippoliti, S. (1990). Primates of the Harenna Forest, Ethiopia. Primate Conservation, 11, 12–15.Google Scholar
  12. Chapman, C., & Chapman, L. M. (1984). Territoriality in the St. Kitts vervet, Cercopithecus aethiops. Journal of Human Evolution, 13, 677–686.CrossRefGoogle Scholar
  13. Chapman, C. A., Chapman, L. J., Cords, M., Gathua, J. M., Gautier-Hion, A., Lambert, J. E., et al. (2002a). Variation in the diets of Cercopithecus species: Differences within forests, among forests, and across species. In M. Glenn & M. Cords (Eds.), The Guenons: Diversity and adaptation of African monkeys (pp. 325–350). New York: Kluwer Academic/Plenum Press.Google Scholar
  14. Chapman, C. A., Chapman, L. J., & Gillespie, T. R. (2002b). Scale issues in the study of primate foraging: red colobus of Kibale National Park. American Journal of Physical Anthropology, 117, 349–363.CrossRefPubMedGoogle Scholar
  15. Chapman, C. A., Lawes, M. J., & Eeley, H. A. C. (2006). What hope for African primate diversity? African Journal of Ecology, 44, 116–133.CrossRefGoogle Scholar
  16. Cheney, D. L. (1981). Intergroup encounters among free-ranging vervet monkeys. Folia Primatologica, 35, 124–146.CrossRefGoogle Scholar
  17. Chivers, D. J. (1994). Functional anatomy of the gastrointestinal tract. In A. G. Davies & J. F. Oates (Eds.), Colobine monkeys: Their ecology, behavior and evolution (pp. 205–227). Cambridge: Cambridge University Press.Google Scholar
  18. Clutton-Brock, T. H., & Harvey, P. H. (1977). Species differences in feeding and ranging behavior in primates. In T. H. Clutton-Brock (Ed.), Primate ecology (pp. 557–583). London: Academic Press.Google Scholar
  19. Cords, M. (1986). Interspecific and intraspecific variation in diet of two forest guenons, Cercopithecus ascanius and C. mitis. Journal of Animal Ecology, 55, 811–827.CrossRefGoogle Scholar
  20. Cords, M. (1987). Mixed-species association of Cercopithecus monkeys in the Kakamega Forest, Kenya. University of California Publications Zoology, 117, 1–109.Google Scholar
  21. Di Fiore, A., & Campbell, C. J. (2007). The atelines: Variation in ecology, behavior, and social organization. In C. J. Campbell, A. Fuentes, K. MacKinnon, M. Panger & S. K. Bearder (Eds.), Primates in perspective (pp. 155–185). Oxford: Oxford University Press.Google Scholar
  22. Enstam, K. L., & Isbell, L. A. (2007). The guenons (Genus Cercopithecus) and their allies. In C. J. Campbell, A. Fuentes, K. MacKinnon, M. Panger & S. K. Bearder (Eds.), Primates in perspective (pp. 252–274). Oxford: Oxford University Press.Google Scholar
  23. Fashing, P. J. (2001a). Activity and ranging patterns of guerezas in the Kakamega Forest: intergroup variation and implications for intragroup feeding competition. International Journal of Primatology, 22, 549–577.CrossRefGoogle Scholar
  24. Fashing, P. J. (2001b). Feeding ecology of guerezas in the Kakamega Forest, Kenya: the importance of Moraceae fruit in their diet. International Journal of Primatology, 22, 579–609.CrossRefGoogle Scholar
  25. Fashing, P. J. (2007a). African colobine monkeys: Patterns of between-group interaction. In C. J. Campbell, A. Fuentes, K. C. MacKinnon, M. Panger & S. K. Bearder (Eds.), Primates in perspective (pp. 201–224). Oxford: Oxford University Press.Google Scholar
  26. Fashing, P. J. (2007b). Behavior, ecology and conservation of colobine monkeys: an introduction. International Journal of Primatology, 28, 507–511.CrossRefGoogle Scholar
  27. Fashing, P. J., Dierenfeld, E. S., & Mowry, C. B. (2007a). Influence of plant and soil chemistry on food selection, ranging patterns, and biomass of Colobus guereza in Kakamega Forest, Kenya. International Journal of Primatology, 28, 673–703.CrossRefGoogle Scholar
  28. Fashing, P. J., Mulindahabi, F., Gakima, J., Masozera, M., Mununura, I., Plumptre, A. J., et al. (2007b). Activity and ranging patterns of Colobus angolensis ruwenzorii in Nyungwe Forest, Rwanda: Possible costs of large group size. International Journal of Primatology, 28, 529–550.CrossRefGoogle Scholar
  29. Gathua, J. M. (2000). Intraspecific variation in foraging patterns of redtail monkeys (Cercopithecus ascanius) in the Kakamega Forest, Kenya. Ph.D. thesis. Columbia University, New York.Google Scholar
  30. Gould, L., & Sauther, M. (2007). Lemuriformes. In C. J. Campbell, A. Fuentes, K. C. MacKinnon, M. Panger & S. K. Bearder (Eds.), Primates in perspective (pp. 46–72). Oxford: Oxford University Press.Google Scholar
  31. Grassi, C. (2006). Variability in habitat, diet, and social structure of Hapalemur griseus in Ranomafana National Park, Madagascar. American Journal of Physical Anthropology, 131, 50–63.CrossRefPubMedGoogle Scholar
  32. Groves, C. P. (2005). Order primates. In D. E. Wilson & D. M. Reeder (Eds.), Mammal species of the world. A taxonomic and geographic reference (3rd ed., pp. 111–184). Baltimore: Johns Hopkins University Press.Google Scholar
  33. Harcourt, A. H., Coppeto, S. A., & Parks, S. A. (2002). Rarity, specialization and extinction in primates. Journal of Biogeography, 29, 445–456.CrossRefGoogle Scholar
  34. Harrison, M. J. S. (1983a). Age and sex differences in the diet and feeding strategies of the green monkey, Cercopithecus sabaeus. Animal Behaviour, 31, 969–977.CrossRefGoogle Scholar
  35. Harrison, M. J. S. (1983b). Territorial behavior in the green monkey, Cercopithecus sabaeus: seasonal defense of local food supplies. Behavioral Ecology and Sociobiology, 12, 85–94.CrossRefGoogle Scholar
  36. Isbell, L. A. (1991). Contest and scramble competition: patterns of female aggression and ranging behavior among primates. Behavioral Ecology, 2, 143–155.CrossRefGoogle Scholar
  37. Isbell, L. A., Pruetz, J. D., & Young, T. P. (1998). Movements of vervets (Cercopithecus aethiops) and patas monkeys (Erythrocebus patas) as estimators of food resource size, density, and distribution. Behavioral Ecology and Sociobiology, 42, 123–133.CrossRefGoogle Scholar
  38. Kaplin, B. A. (2001). Ranging behavior of two species of guenons (Cercopithecus lhoesti and C. mitis doggetti) in the Nyungwe Forest Reserve, Rwanda. International Journal of Primatology, 22, 521–548.CrossRefGoogle Scholar
  39. Kaplin, B. A., & Moermond, T. C. (2000). Foraging ecology of the mountain monkey (Cercopithecus l’hoesti): Implications for its evolutionary history and use of disturbed forest. American Journal of Primatology, 50, 227–246.CrossRefPubMedGoogle Scholar
  40. Kaplin, B. A., Munyaligoga, V., & Moermond, T. C. (1998). The influence of temporal changes in fruit availability on diet composition and seed handling in blue monkey (Cercopithecus mitis doggetti). Biotropica, 30, 56–71.CrossRefGoogle Scholar
  41. Kavanagh, M. (1981). Variable territoriality among tantalus monkeys in Cameroon. Folia Primatologica, 36, 76–98.CrossRefGoogle Scholar
  42. Krebs, C. J. (1989). Ecological methodology. New York: HarperCollins.Google Scholar
  43. Lee, P. C., & Hauser, M. D. (1998). Long-term consequence of changes in territory quality on feeding and reproductive strategies of vervet monkeys. Journal of Animal Ecology, 67, 347–358.CrossRefGoogle Scholar
  44. Mekonnen, A., Bekele, A., Hemson, G., Teshome, E., & Atickem, A. (in press). Population size and habitat preference of the vulnerable Bale monkey (Chlorocebus djamdjamensis) in Odobullu Forest and its distribution across the Bale Mountains, Ethiopia. Oryx Google Scholar
  45. Milton, K. (1979). Factors influencing leaf choice by howler monkeys: a test of some hypotheses of food selection by generalist herbivores. American Naturalist, 114, 362–378.CrossRefGoogle Scholar
  46. Muoria, P. K., Karere, G. M., Moinde, N. N., & Suleman, M. A. (2003). Primate census and habitat evaluation in the Tana delta region, Kenya. African Journal of Ecology, 41, 157–163.CrossRefGoogle Scholar
  47. Mutschler, T., Feistner, A. T. C., & Nievergelt, C. M. (1998). Preliminary field data on group size, diet and activity in the Alaotran gentle lemur, Hapalemur griseus alaotrensis. Folia Primatologica, 69, 325–330.CrossRefGoogle Scholar
  48. Myers, N., Mittermeier, R. A., Mittermeier, C. G., Fonseca, G. A. B., & Kent, J. (2000). Biodiversity hotspots for conservation priorities. Nature, 403, 853–858.CrossRefPubMedGoogle Scholar
  49. Overdorff, D. J., Strait, S. G., & Telo, A. (1997). Seasonal variation in activity and diet in a small-bodied folivorous primate, Hapalemur griseus, in southeastern Madagascar. American Journal of Primatology, 43, 211–223.CrossRefPubMedGoogle Scholar
  50. Plumptre, A. J. (2006). The diets, preferences, and overlap of the primate community in the Budongo Forest Reserve, Uganda: effects of logging on primate diets. In N. E. Newton-Fisher, H. Notman, J. D. Paterson & V. Reynolds (Eds.), Primates of Western Uganda (pp. 345–371). New York: Springer.CrossRefGoogle Scholar
  51. Plumptre, A. J., Masozera, M., Fashing, P. J., McNeilage, A., Ewango, C., Kaplin, B. A., et al. (2002). Biodiversity surveys of the Nyungwe Forest Reserve in S.W. Rwanda. WCS Working Paper No. 18.Google Scholar
  52. Sprague, D. S. (2000). Topographic effects on spatial data at a Japanese macaque study site. American Journal of Primatology, 52, 143–147.CrossRefPubMedGoogle Scholar
  53. Struhsaker, T. T. (1967). Ecology of vervet monkeys (Cercopithecus aethiops) in the Masai-Amboseli Game Reserve, Kenya. Ecology, 48, 891–904.CrossRefGoogle Scholar
  54. Struhsaker, T. T. (1978). Food habits of five monkey species in the Kibale Forest, Uganda. In D. J. Chivers & J. Herbert (Eds.), Recent advances in primatology vol. 1: Behaviour (pp. 225–248). London: Academic Press.Google Scholar
  55. Struhsaker, T. T. (1981). Census methods for estimating densities. In Anonymous (Ed.), Techniques for the study of primate population ecology (pp. 36–80). Washington: National Academy Press.Google Scholar
  56. Tan, C. L. (1999). Group composition, home range size, and diet of three sympatric bamboo lemur species (genus Hapalemur) in Ranomafana National Park, Madagascar. International Journal of Primatology, 20, 547–566.CrossRefGoogle Scholar
  57. Twinomugisha, D., & Chapman, C. A. (2008). Golden monkey ranging in relation to spatial and temporal variation in food availability. African Journal of Ecology, 46, 585–593.CrossRefGoogle Scholar
  58. Twinomugisha, D., Chapman, C. A., Lawes, M. J., O’Driscoll Worman, C., & Danish, L. M. (2006). How does the golden monkey of the Virungas cope in a fruit-scarce environment? In N. E. Newton-Fisher, H. Notman, J. D. Paterson & V. Reynolds (Eds.), Primates of Western Uganda (pp. 45–60). New York: Springer.CrossRefGoogle Scholar
  59. Whitten, P. L. (1983). Diet and dominance among female vervet monkeys (Cercopithecus aethiops). American Journal of Primatology, 5, 139–159.CrossRefGoogle Scholar
  60. Wieczkowski, J. (2004). Ecological correlates of abundance in the Tana mangabey (Cercocebus galeritus). American Journal of Primatology, 63, 125–138.CrossRefPubMedGoogle Scholar
  61. Wong, S. N. P., & Sicotte, P. (2007). Activity budget and ranging patterns of Colobus vellerosus in forest fragments in Central Ghana. Folia Primatologica, 78, 245–254.CrossRefGoogle Scholar
  62. Worton, B. J. (1987). A review of models of home range for animal movement. Ecological Modelling, 38, 277–298.CrossRefGoogle Scholar

Copyright information

© Springer Science+Business Media, LLC 2010

Authors and Affiliations

  • Addisu Mekonnen
    • 1
    Email author
  • Afework Bekele
    • 1
  • Peter J. Fashing
    • 2
  • Graham Hemson
    • 3
  • Anagaw Atickem
    • 4
  1. 1.Department of BiologyAddis Ababa UniversityAddis AbabaEthiopia
  2. 2.Department of AnthropologyCalifornia State University FullertonFullertonUSA
  3. 3.Ethiopian Wolf Conservation ProgrammeRobeEthiopia
  4. 4.Centre for Ecological and Evolutionary Synthesis, Department of BiologyUniversity of OsloOsloNorway

Personalised recommendations