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Mountain Gorillas: A Shifting Demographic Landscape

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Primates and Cetaceans

Part of the book series: Primatology Monographs ((PrimMono))

Abstract

Large-scale habitat destruction and poaching in the 1950s, 1960s, and 1970s had major impacts on the population size and demography of mountain gorillas (Gorilla beringei beringei) in Rwanda. In those three decades, the population of the Virunga Volcanoes was halved: groups became unstable, and infanticide was relatively common. Intensive conservation efforts began in the 1980s and have enabled the gorilla population to recover. The present study took place during a period of social stability in the lives of three Karisoke gorilla groups. Characterized by few female transfers, no known infanticide, and only one silverback male departure from the research groups, there were striking increases in both group size and the number of adult males per group. I consider how these changes have occurred and implications for the management of this Critically Endangered primate. Despite encouraging growth, this population is so small that it remains extremely vulnerable to human disturbance. If mountain gorillas are to survive in this volatile region, a hands-on approach to their conservation may be justified.

figure a

Adult male “silverback” mountain gorilla with infant. (© David Pluth)

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References

  • Bradley BJ, Robbins MM, Williamson EA, Steklis HD, Gerald-Steklis N, Eckhardt N, Boesch C, Vigilant L (2005) Mountain gorilla tug-of-war: silverbacks have limited control over reproduction in multi-male groups. Proc Natl Acad Sci USA 102:9418–9423

    Article  PubMed Central  CAS  PubMed  Google Scholar 

  • Cranfield M, Gaffikin L, Minnis R, Nutter F, Rwego I, Travis D, Whittier C (2006) Clinical response decision tree for the mountain gorilla (Gorilla beringei) as a model for great apes. Am J Primatol 68:909–927

    Article  Google Scholar 

  • Czekala N, Sicotte P (2000) Reproductive monitoring of free-ranging female mountain gorillas by urinary hormone analysis. Am J Primatol 51:209–215

    Article  CAS  PubMed  Google Scholar 

  • Fossey D (1983) Gorillas in the mist. Houghton-Mifflin, Boston

    Google Scholar 

  • Gray M, McNeilage A, Fawcett K, Robbins MM, Ssebide B, Mbula D, Uwingeli P (2009) Censusing the mountain gorillas in the Virunga Volcanoes: complete sweep method vs. monitoring. Afr J Ecol 48:588–599

    Google Scholar 

  • Gray M, Roy J, Vigilant L, Fawcett K, Basabose A, Cranfield M, Uwingeli P, Mburunumwe I, Kagoda E, Robbins MM (2013) Genetic census reveals increased but uneven growth of a critically endangered mountain gorilla population. Biol Conserv 158:230–238

    Article  Google Scholar 

  • Harcourt AH (1981) Intermale competition and the reproductive biology of the great apes. In: Graham CE (ed) Reproductive biology of the great apes, comparative and biomedical perspectives. Academic, New York, pp 301–318

    Chapter  Google Scholar 

  • Harcourt AH, Stewart KJ (1981) Gorilla male relationships: can differences during immaturity lead to contrasting reproductive tactics in adulthood? Anim Behav 29:206–210

    Article  Google Scholar 

  • Harcourt AH, Stewart KJ (2007) Gorilla society: conflict, compromise, and cooperation between the sexes. University of Chicago Press, Chicago

    Book  Google Scholar 

  • Harcourt AH, Fossey D, Stewart KJ, Watts DP (1980) Reproduction in wild gorillas and some comparisons with chimpanzees. J Reprod Fertil Suppl 28:59–70

    PubMed  Google Scholar 

  • Kalpers J, Williamson EA, Robbins MM, McNeilage A, Nzamurambaho A, Lola N, Mugiri G (2003) Gorillas in the crossfire: assessment of population dynamics of the Virunga mountain gorillas over the past three decades. Oryx 37:326–337

    Article  Google Scholar 

  • Macfie EJ, Williamson EA (2010) Best practice guidelines for great ape tourism. IUCN/SSC Primate Specialist Group, Gland

    Google Scholar 

  • McNeilage A (2001) Diet and habitat use of two mountain gorilla groups in contrasting habitats in the Virungas. In: Robbins MM, Sicotte P, Stewart KJ (eds) Mountain gorilla: three decades of research at Karisoke. Cambridge University Press, Cambridge, pp 265–292

    Chapter  Google Scholar 

  • Palacios G, Lowenstine LJ, Cranfield MR, Gilardi KV, Spelman L, Lukasik-Braum M, Kinani J-F, Mudakikwa A, Nyirakaragire E, Bussetti AV, Savji N, Hutchison S, Egholm M, Lipkin WI (2011) Human metapneumovirus infection in wild mountain gorillas, Rwanda. Emerg Infect Dis 17:711–713

    Article  PubMed Central  PubMed  Google Scholar 

  • Parnell RJ (2002) Group size and structure in western lowland gorillas (Gorilla gorilla gorilla) at Mbeli Bai, Republic of Congo. Am J Primatol 56:193–206

    Article  PubMed  Google Scholar 

  • Plumptre AJ, Williamson EA (2001) Conservation oriented research in the Virunga region. In: Robbins MM, Sicotte P, Stewart KJ (eds) Mountain gorilla: three decades of research at Karisoke. Cambridge University Press, Cambridge, pp 361–390

    Google Scholar 

  • Robbins MM (1995) A demographic analysis of male life history and social structure of mountain gorillas. Behaviour 132:21–47

    Article  Google Scholar 

  • Robbins MM (1996) Male–male interactions in heterosexual and all-male wild mountain gorilla groups. Ethology 102:942–965

    Article  Google Scholar 

  • Robbins MM (1999) Male mating patterns in wild multimale mountain gorilla groups. Anim Behav 57:1013–1020

    Article  PubMed  Google Scholar 

  • Robbins MM (2001) Variation in the social system of mountain gorillas: the male perspective. In: Robbins MM, Sicotte P, Stewart KJ (eds) Mountain gorilla: three decades of research at Karisoke. Cambridge University Press, Cambridge, pp 29–58

    Chapter  Google Scholar 

  • Robbins MM (2003) Behavioural aspects of sexual selection in mountain gorillas. In: Jones CB (ed) Sexual selection and reproductive competition in primates: new perspectives and directions. American Society of Primatologists, Norman, pp 477–501

    Google Scholar 

  • Robbins MM, Robbins AM (2004) Simulation of the population dynamics and social structure of the Virunga mountain gorillas. Am J Primatol 63:201–223

    Article  PubMed  Google Scholar 

  • Robbins AM, Robbins MM (2005) Fitness consequences of dispersal decisions for male mountain gorillas (Gorilla beringei beringei). Behav Ecol Sociobiol 58:295–309

    Article  Google Scholar 

  • Robbins M, Williamson EA (2008) Gorilla beringei. In: IUCN 2012. IUCN red list of threatened species. Version 2012.2. <www.iucnredlist.org>

  • Robbins MM, Gray M, Fawcett KA, Nutter FB, Uwingeli P, Mburanumwe I, Kagoda E, Basabose A, Stoinski TS, Cranfield MR, Byamukama J, Spelman LH, Robbins AM (2011) Extreme conservation leads to recovery of the Virunga mountain gorillas. PLoS One 6:e19788. doi:10.1371/journal.pone.0019788

    Article  PubMed Central  CAS  PubMed  Google Scholar 

  • Routh A, Sleeman J (1997) A preliminary survey of syndactyly in the mountain gorilla (Gorilla gorilla beringei). In: British Veterinary Zoological Society (ed) Proceedings of the medical conditions and veterinary considerations of zoo animals. Tamurlane, Canterbury, pp 22–25

    Google Scholar 

  • Ryan SJ, Walsh PD (2011) Consequences of non-intervention for infectious disease in African great apes. PLoS One 6:e29030. doi:10.1371/journal.pone.0029030

    Article  PubMed Central  CAS  PubMed  Google Scholar 

  • Sicotte P (1993) Inter-group encounters and female transfer in mountain gorillas: influence of group composition on male behavior. Am J Primatol 30:21–36

    Article  Google Scholar 

  • Sicotte P (2001) Female mate choice in mountain gorillas. In: Robbins MM, Sicotte P, Stewart KJ (eds) Mountain gorilla: three decades of research at Karisoke. Cambridge University Press, Cambridge, pp 59–87

    Chapter  Google Scholar 

  • Stoinski TS, Hoff MP, Lukas KE, Maple TL (2001) A preliminary behavioral comparison of two captive all-male gorilla groups. Zoo Biol 20:27–40

    Article  PubMed  Google Scholar 

  • Stoinski TS, Lukas KE, Kuhar CW, Maple TL (2004) Factors influencing the formation and maintenance of all-male gorilla groups in captivity. Zoo Biol 23:189–203

    Article  Google Scholar 

  • Stoinski TS, Vecellio V, Ngaboyamahina T, Ndagijimana F, Rosenbaum S, Fawcett KA (2009) Proximate factors influencing dispersal decisions in male mountain gorillas, Gorilla beringei beringei. Anim Behav 77:1155–1164

    Article  Google Scholar 

  • Tutin CEG (1996) Ranging and social structure of lowland gorillas in the Lopé Reserve, Gabon. In: McGrew WC, Marchant LF, Nishida T (eds) Great ape societies. Cambridge University Press, Cambridge, pp 58–70

    Chapter  Google Scholar 

  • Vecellio V (2008) Rapid decline in the largest group of mountain gorillas. Gorilla J 37:6–7

    Google Scholar 

  • Warren Y, Williamson EA (2004) Transport of dead infant mountain gorillas by mothers and unrelated females. Zoo Biol 23:375–378

    Article  Google Scholar 

  • Watts DP (1983) Foraging strategy and socioecology of mountain gorillas (Pan gorilla beringei). Ph.D. Thesis, University of Chicago, IL

    Google Scholar 

  • Watts DP (1989) Infanticide in mountain gorillas: new cases and a reconsideration of the evidence. Ethology 81:1–18

    Article  Google Scholar 

  • Watts DP (1991) Mountain gorilla reproduction and sexual behavior. Am J Primatol 24:211–218

    Article  Google Scholar 

  • Watts DP (1996) Comparative socioecology of gorillas. In: McGrew WC, Marchant LF, Nishida T (eds) Great ape societies. Cambridge University Press, Cambridge, pp 16–28

    Chapter  Google Scholar 

  • Watts DP (2000) Causes and consequences of variation in male mountain gorilla life histories and group membership. In: Kappeler P (ed) Primate males. Cambridge University Press, Cambridge, pp 169–179

    Google Scholar 

  • Watts DP, Pusey AE (1993) Behaviour of juvenile and adolescent great apes. In: Pereira ME, Fairbanks LA (eds) Juvenile primates; life history, development and behavior. Oxford University Press, New York, pp 148–167

    Google Scholar 

  • Williamson EA, Gerald-Steklis N (2001) Composition of gorilla groups monitored by Karisoke Research Center, 2001. Afr Primates 5:48–51

    Google Scholar 

  • Yamagiwa J (1987a) Intra- and inter-group interactions of an all-male group of Virunga mountain gorillas (Gorilla gorilla beringei). Primates 28:1–30

    Article  Google Scholar 

  • Yamagiwa J (1987b) Male life history and the social structure of wild mountain gorillas (Gorilla gorilla beringei). In: Kawano S, Connell JH, Hidaka T (eds) Evolution and coadaptation in biotic communities. University of Tokyo Press, Tokyo, pp 31–51

    Google Scholar 

  • Yamagiwa J, Kahekwa J (2001) Dispersal patterns, group structure, and reproductive parameters of eastern lowland gorillas at Kahuzi in the absence of infanticide. In: Robbins MM, Sicotte P, Stewart KJ (eds) Mountain gorilla: three decades of research at Karisoke. Cambridge University Press, Cambridge, pp 90–122

    Google Scholar 

  • Yamagiwa J, Kahekwa J, Basabose AK (2009) Infanticide and social flexibility in the genus Gorilla. Primates 50:293–303

    Article  PubMed  Google Scholar 

Download references

Acknowledgments

  I thank the Rwandan Office of Tourism and National Parks for permission to work in the Volcanoes National Park and the Dian Fossey Gorilla Fund International for making this research possible. I am very grateful to J.R. Anderson, R.W. Byrne, M. Klailova, W.C. McGrew, R.J. Parnell, M.M. Robbins, M.E. Rogers, and C.E.G. Tutin for providing valuable comments on the manuscript. I am indebted to the staff of the Karisoke Research Centre, in particular Jean Damascene Hategekimana, Emmanuel Hitayezu, and the late Mathias Mpiranya, for sharing with me their insights to the gorillas’ world. But most especially, I am deeply grateful to Jean Bosco Bizumuremyi, without whose endless dedication, energy, and personal sacrifice, we would have been much less effective in protecting the gorillas during very difficult times when so many people lost their lives.

Parnell © 2002 Wiley is quoted with permission from the author and the publisher.

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Authors and Affiliations

  1. Psychology, School of Natural Sciences, University of Stirling, Scotland, UK

    Elizabeth A. Williamson

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  1. Elizabeth A. Williamson
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Correspondence to Elizabeth A. Williamson .

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Editors and Affiliations

  1. Graduate School of Science Laboratory of Human Evolution Studies, Kyoto University, Kyoto, Japan

    Juichi Yamagiwa

  2. The Swire Institute of Marine Science School of Biological Sciences, The University of Hong Kong, Shek O, Hong Kong SAR

    Leszek Karczmarski

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Williamson, E.A. (2014). Mountain Gorillas: A Shifting Demographic Landscape. In: Yamagiwa, J., Karczmarski, L. (eds) Primates and Cetaceans. Primatology Monographs. Springer, Tokyo. https://doi.org/10.1007/978-4-431-54523-1_14

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