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Nesting Behavior of Gorilla gorilla diehli at Kagwene Mountain, Cameroon: Implications for Assessing Group Size and Density

Abstract

We recorded nesting data at 569 fresh night nest sites, comprising 7032 individual nests, of Cross River gorillas inhabiting the Kagwene Mountain in western Cameroon. The mean night nest group size was 12.4. Overall, 55% of night nests were constructed on the ground and 45% in trees. Significantly more arboreal nests were constructed in the wet season (69%), vs. the dry season (19%). Day nest construction was common at Kagwene (n = 260 nest sites, mean nest group size = 5.98) and we encountered significantly more day nest sites in the wet season. Nest site reuse was also common (35%), though not related to season. Our results of nesting habits concur with those from other western gorilla studies, in which rainfall influences arboreal nesting. However, we encountered wet season arboreal nesting, day nest construction, and overall nest site reuse more frequently than reported for other sites. Our observations have considerable implications when estimating group size and density using traditional nest count data. The gorillas at Kagwene inhabit the highest altitudinal range of all Cross River gorilla subpopulations and rainfall is also high; therefore other subpopulations may demonstrate different nesting characteristics. However, one should consider our findings when attempting to estimate Cross River gorilla density at other localities through nest site data.

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References

  1. Asaha, S., & Abwe, M. N. (2004). Socio economic baseline study of the communities around the Kagwene area. Unpublished consultancy report to the Wildlife Conservation Society-Cross River Gorilla Research Project.

  2. Bergl, R.A. (2006). Conservation Biology of the Cross River gorilla (Gorilla gorilla diehli). Ph.D. thesis, City University of New York.

  3. Bergl, R. A., & Vigilant, L. (2006). Genetic analysis reveals population structure and recent migration within the highly fragmented range of the Cross River gorilla (Gorilla gorilla diehli). Molecular Ecology, 16, 501–516. doi:10.1111/j.1365-294X.2006.03159.x.

    Article  Google Scholar 

  4. Bermejo, M. (1999). Status and conservation of primates in Odzala National Park, Republic of Congo. Oryx, 33, 323–331. doi:10.1046/j.1365-3008.1999.00081.x.

    Article  Google Scholar 

  5. Blom, A., Almasi, A., Heitkönig, I. M. A., Kpanou, J. -B., & Prins, H. H. T. (2001). A survey of the apes in the Dzanga-Ndoki National Park, Central African Republic: A comparison between the census and survey methods of estimating the gorilla (Gorilla gorilla gorilla) and chimpanzee (Pan troglodytes) nest group density. African Journal of Ecology, 39, 98–105. doi:10.1046/j.0141-6707.2000.00280.x.

    Article  Google Scholar 

  6. Brugiere, D., & Sakom, D. (2001). Population density and nesting behaviour of lowland gorillas (Gorilla gorilla gorilla) in the Ngotto forest, Central African Republic. Journal of Zoology, 255, 251–259. doi:10.1017/S0952836901001315.

    Article  Google Scholar 

  7. Cipolletta, C., Spagnoletii, N., Todd, A., Robbins, M. M., Cohen, H., & Pocyna, S. (2007). Termite feeding by Gorilla gorilla gorilla at Bai Hokou, Central African Republic. International Journal of Primatology, 28, 457–476. doi:10.1007/s10764-007-9129-5.

    Article  Google Scholar 

  8. Dupain, J., Guislain, P., Nguenang, G. M., De Vleeschouwer, K. & Van Elsacker, L. (2004). High chimpanzee and gorilla densities in a non-protected area on the northern periphery of the Dja Faunal Reserve, Cameroon. Oryx, 38, 209–216.

    Article  Google Scholar 

  9. Fay, J. M. (1989). Partial completion of a census of the western lowland gorilla (Gorilla g. gorilla (Savage and Wyman)) in southwestern Central African Republic. Mammalia, 53, 203–215.

    Article  Google Scholar 

  10. Fay, M. J., Carroll, R. W., Paterhans, C. K., & Harris, D. (1995). Leopard attack on and consumption of gorillas in the Central African Republic. Journal of Human Evolution, 29, 93–99. doi:10.1006/jhev.1995.1048.

    Article  Google Scholar 

  11. Fruth, B., & Hohmann, G. (1996). Nest building in the great apes: The great leap forward? In W. C. McGrew, L. F. Marchant, & T. Nishida (Eds.), Great Ape Societies (pp. 225–240). Cambridge, UK: Cambridge University Press.

    Google Scholar 

  12. Hall, J. S., White, L., Inogwabini, J. T., Omari, B. I., Simons, I., Morland, H., et al. (1998). Survey of Grauer’s gorillas (Gorilla gorilla graueri) and eastern chimpanzees (Pan troglodytes schweinfurthi) in the Kahuzi-Biega National Park lowland sector and adjacent forest in eastern Democratic Republic of Congo. International Journal of Primatology, 19, 207–235. doi:10.1023/A:1020375430965.

    Article  Google Scholar 

  13. Iwata, Y., & Ando, C. (2007). Bed and bed-site reuse by western lowland gorillas (Gorilla g. gorilla) in Moukalaba-Doudou National Park, Gabon. Primates, 48, 77–80. doi:10.1007/s10329-006-0003-4.

    PubMed  Article  Google Scholar 

  14. Jones, C., & Sabater Pi, J. (1971). Comparative ecology of Gorilla gorilla (Savage and Wyman) and Pan troglodytes (Blumenbach) in Rio Muni, West Africa. Bibliotheca Primatologica, 13, 1–96. doi:10.1159/000175313.

    Article  Google Scholar 

  15. Matthews, A., & Matthews, A. (2004). Survey of gorillas (Gorilla gorilla gorilla) and chimpanzees (Pan troglodytes troglodytes) in Southwestern Cameroon. Primates, 45, 15–24. doi:10.1007/s10329-003-0058-4.

    PubMed  Article  Google Scholar 

  16. McFarland, K. L. (2007). Ecology of Cross River gorillas (Gorilla gorilla diehli) on Afi Mountain, Cross River State, Nigeria. Ph.D. thesis, City University of New York.

  17. Mehlman, P. T., & Doran, D. M. (2002). Influencing western gorilla nest construction at Mondika Research Centre. International Journal of Primatology, 23, 1257–1285. doi:10.1023/A:1021126920753.

    Article  Google Scholar 

  18. Mittermeier, R. A., Valladores-Padua, C., Rylands, A. B., Eudey, A. A., Butynski, T. M., Ganzhorn, J. U., et al. (2006). Primates in peril: The world’s 25 most endangered primates 2004–2006. Primate Conservation, 20, 1–28. doi:10.1896/0898-6207.20.1.1.

    Article  Google Scholar 

  19. Oates, J., Sunderland-Groves, J., Bergl, R., Dunn, A., Nicholas, A., Takang, E., et al. (2007). Regional action plan for the conservation of the Cross River gorilla (Gorilla gorilla diehli) p. 36. Arlington, VA: IUCN/SSC Primate Specialist Group and Conservation International.

    Google Scholar 

  20. Oates, J., White, D., Gadsby, E. L., & Bisong, P. O. (1990). Cross River National Park (Okwangwo Division), feasibility study. Appendix I. Conservation of gorillas and other species.

  21. Oates, J. F., McFarland, K. L., Groves, J. L., Bergl, R. A., Linder, J. M., & Disotell, T. R. (2003). The Cross River gorilla: Natural history and status of a neglected and critically endangered subspecies. In A. B. Taylor, & M. L. Goldsmith (Eds.), Gorilla Biology: A Multidisciplinary Perspective (pp. 472–497). Cambridge, UK: Cambridge University Press.

    Google Scholar 

  22. Remis, M. J. (1993). Nesting behaviour of lowland gorillas in the Dzanga-Sangha Reserve, Central African Republic: Implications for population estimates and understandings of group dynamics. Tropics, 2, 245–255.

    Google Scholar 

  23. Rothman, J. M., Pell, A. N., Dierenfeld, E. S., & McCann, C. M. (2006). Plant choice in the construction of night nests by gorillas in the Bwindi Impenetrable National Park, Uganda. American Journal of Primatology, 68, 361–368. doi:10.1002/ajp.20230.

    PubMed  Article  Google Scholar 

  24. Sarmiento, E. E. (2003). The Cross River gorilla: The most endangered gorilla subspecies. Primate Conservation, 19, 65–72.

    Google Scholar 

  25. Schaller, G. B. (1963). The Mountain Gorilla: Ecology and Behaviour. Chicago: University of Chicago Press.

    Google Scholar 

  26. Sunderland-Groves, J. L. (2008). Population, distribution and conservation status of the Cross River gorilla (Gorilla gorilla diehli) in Cameroon. MPhil thesis, University of Sussex, UK.

  27. Sunderland-Groves, J. L., Maisels, F., & Ekinde, A. (2003). Surveys of the Cross River gorilla and chimpanzee populations in Takamanda Forest Reserve. In J. A. Comiskey, T. C. H. Sunderland, & J. L. Sunderland-Groves (Eds.), Takamanda: The Biodiversity of an African Rainforest (pp. 129–140). Washington, DC: Smithsonian Institution SI/MAB Series no. 8.

    Google Scholar 

  28. Tutin, C. E. G., & Fernandez, M. (1984). Nationwide census of gorilla (Gorilla g. gorilla) and chimpanzee (Pan t. troglodytes) populations in Gabon. American Journal of Primatology, 6, 313–336. doi:10.1002/ajp.1350060403.

    Article  Google Scholar 

  29. Tutin, C. E. G., & Fernandez, M. (1993). Fecal analysis as a method of describing diets of apes: Examples from sympatric gorillas and chimpanzees at Lopé, Gabon. Tropics, 2, 189–197.

    Article  Google Scholar 

  30. Tutin, C. E. G., Fernandez, M., Rogers, M. E., & Williamson, E. A. (1992). A preliminary analysis of the social structure of lowland gorillas in the Lopé Réserve, Gabon. In N. Itoigawa, Y. Sugiyama, G. P. Sackett, & R. K. R. Thompson (Eds.), Topics in Primatology, Vol. 2: Behavior, Ecology and Conservation (pp. 245–254). Tokyo: University of Tokyo Press.

    Google Scholar 

  31. Tutin, C. E. G., Parnell, R. J., White, L. J. T., & Fernandez, M. (1995). Nest building by lowland gorillas in the Lopé Réserve, Gabon: Environmental influences and implications for censusing. International Journal of Primatology, 16, 53–76. doi:10.1007/BF02700153.

    Article  Google Scholar 

  32. Williamson, E. A. (1988). Behavioural ecology of western lowland gorillas in Gabon. UK: Ph.D. thesis, University of Stirling.

  33. Wittiger, L., & Sunderland-Groves, J. L. (2007). Tool use during display behavior in wild Cross River gorillas. American Journal of Primatology, 69, 1307–1311. doi:10.1002/ajp.20436.

    PubMed  Article  CAS  Google Scholar 

  34. Yamagiwa, J. (2001). Factors influencing the formation of ground nests by eastern lowland gorillas in Kahuzi-Biega National Park: Some evolutionary implications of nesting behaviour. Journal of Human Evolution, 40, 99–109. doi:10.1006/jhev.2000.0444.

    PubMed  Article  CAS  Google Scholar 

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Acknowledgments

We thank the Government of Cameroon Ministry of Forestry and Wildlife and Ministry of Scientific and Technical Research for permission to conduct this study. Several researchers, assistants and field guides aided data collection and we particularly thank Luisa Rabanal, Matt Wormall, Livia Wittiger, Nfor Constantine; guides, Tampi Richard, Ndo John, Asseke Emmanuel, and Tiku David and camp keepers Tiko Simon and Lucas Tiku for their dedication and contribution to this finding, together with the local communities for their support and cooperation. We also thank John Oates, Terry Sunderland, Fiona Maisels, and Daniel Slayback for providing comments on an earlier draft of this manuscript and to Daniel Slayback of SSAI/NASA Goddard Space Flight Center, Maryland, for providing us with maps. We thank 2 anonymous reviewers for their valuable comments on this manuscript. Funding from the Wildlife Conservation Society, the United States Fish and Wildlife Service, the Margot Marsh Biodiversity Foundation, and WWF-African Great Apes Programme supported this study. We conducted this research with authorization and within the research protocols of the Ministry of Forestry and Wildlife and the Ministry of Scientific and Technical Research, Cameroon.

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Correspondence to J. L. Sunderland-Groves.

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Sunderland-Groves, J.L., Ekinde, A. & Mboh, H. Nesting Behavior of Gorilla gorilla diehli at Kagwene Mountain, Cameroon: Implications for Assessing Group Size and Density. Int J Primatol 30, 253–266 (2009). https://doi.org/10.1007/s10764-009-9340-7

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Keywords

  • Cross River gorilla
  • Kagwene mountain
  • nests
  • reuse
  • seasonal