Skip to main content
SpringerLink
Log in

What limits the Serengeti zebra population?

  • Population Ecology
  • Published:
Oecologia Aims and scope Submit manuscript

Abstract

The populations of the ecologically dominant ungulates in the Serengeti ecosystem (zebra, wildebeest and buffalo) have shown markedly different trends since the 1960s: the two ruminants both irrupted after the elimination of rinderpest in 1960, while the zebras have remained stable. The ruminants are resource limited (though parts of the buffalo population have been limited by poaching since the 1980s). The zebras’ resource acquisition tactics should allow them to outcompete the ruminants, but their greater spatial dispersion makes them more available to predators, and it has been suggested that this population is limited by predation. To investigate the mechanisms involved in the population dynamics of Serengeti zebra, we compared population dynamics among the three species using demographic models based on age-class-specific survival and fecundity. The only major difference between zebra and the two ruminants occurred in the first-year survival. We show that wildebeest have a higher reproductive potential than zebra (younger age at first breeding and shorter generation time). Nevertheless, these differences in reproduction cannot account for the observed differences in the population trends between the zebra and the ruminants. On the other hand, among-species differences in first-year survival are great enough to account for the constancy of zebra population size. We conclude that the very low first-year survival of zebra limits this population. We provide new data on predation in the Serengeti and show that, as in other ecosystems, predation rates on zebras are high, so predation could hold the population in a “predator pit”. However, lion and hyena feed principally on adult zebras, and further work is required to discover the process involved in the high mortality of foals.

This is a preview of subscription content, log in via an institution to check access.

Access this article

Log in via an institution

Price excludes VAT (USA)
Tax calculation will be finalised during checkout.

Instant access to the full article PDF.

Institutional subscriptions

Fig. 1
Fig. 2
Fig. 3

Similar content being viewed by others

References

  • Bauer H (2003) Lion conservation in West and Central Africa: integrating social and natural science for wildlife conflict resolution around Waza National Park, Cameroon. PhD thesis, Leiden University, Leiden

    Google Scholar 

  • Bell RHV (1970) The use of the herd layer by grazing ungulates in the Serengeti. Animal populations in relation to their food resources. Blackwell, Oxford

  • Berger J (1986) Wild horses of the Great Basin. Social competition and population size. University of Chicago Press, Chicago, Ill.

  • Caswell H (2001) Matrix population models. Construction, analysis and interpretation. Sinauer, Sunderland, Mass.

  • Cooper SM (1990) The hunting behaviour of spotted hyaenas (Crocuta crocuta) in a region containing both sedentary and migratory populations of herbivores. Afr J Ecol 28:131–141

    Google Scholar 

  • Cumming DHM (1982) The influence of large herbivores on savanna structure in Africa. In: Huntley BJ, Walker BH (eds) Ecology of tropical savannas. Springer, Berlin Heidelberg New York, pp 217–244

  • De Boer W, Prins H (1990) Large herbivores that strive mightily but eat and drink as friends. Oecologia 82:264–274

    Google Scholar 

  • Dublin HT, Sinclair ARE, Boutin S, Anderson E, Jago M, Arcese P (1990) Does competition regulate ungulate populations? Further evidence from Serengeti, Tanzania. Oecologia 82:283–288

    Google Scholar 

  • Duncan P, Foose TJ, Gordon I, Gakahu CG, Lloyd M (1990) Comparative nutrient extraction from forages by grazing bovids and equids: a test of the nutritional model of equid/bovid competition and coexistence. Oecologia 84:411–418

    Google Scholar 

  • Festa-Bianchet M, Gaillard JM, Coté SD (2003) Variable age structure and apparent density-dependence in survival of adult ungulates. J Anim Ecol 72:640–649

    Article  Google Scholar 

  • Fryxell J, Greever J, Sinclair A (1988) Why are migratory ungulates so abundant? Am Nat 131:781–798

    Article  Google Scholar 

  • Gaillard J-M, Festa-Bianchet M, Yoccoz NG (1998) Population dynamics of large herbivores: variable recruitment with constant adult survival. Trends Ecol Evol 13:58–63

    Article  Google Scholar 

  • Gaillard J-M, Festa-Bianchet M, Yoccoz NG, Loison A, Toïgo C (2000) Temporal variation in fitness components and population dynamics of large herbivores. Annu Rev Ecol Syst 31:367–393

    Article  Google Scholar 

  • Gasaway WC, Gasaway KT, Berry HH (1996) Persistent low densities of plains ungulates in Etosha National Park, Namibia: testing the food-regulating hypothesis. Can J Zool 74:1556–1572

    Google Scholar 

  • Georgiadis N, Hack M, Turpin K (2003) The influence of rainfall on zebra population dynamics: implications for management. J Appl Ecol 40:125–136

    Article  Google Scholar 

  • Grimsdell JJR (1973) Age determination of the African buffalo, Syncerus caffer Sparrman. East Afr Wildl J 11:31–54

    Google Scholar 

  • Gwynne MD, Bell RHV (1968) Selection of vegetation components by grazing ungulates in the Serengeti National Park. Nature 220:390–393

    CAS  PubMed  Google Scholar 

  • Hairston NG, Smith FE, Slobotkin LB (1960) Community structure, population control, and competition. Am Nat 44:421–425

    Article  Google Scholar 

  • Hansen RM, Mugambi MM, Bauni SM (1985) Diets and trophic ranking of ungulates of the northern Serengeti. J Wildl Manage 49:823–829

    Google Scholar 

  • Hofer H, East M (1995) Population dynamics, population size, and the commuting system of Serengeti spotted hyenas. In: Sinclair ARE, Arcese P (eds) Serengeti II: dynamics, management, and conservation of an ecosystem. University of Chicago Press, Chicago, Ill., pp 332–363

  • Hofer H, Campbell KLI, East ML, Huish SA (1996) The impact of game meat hunting on target and non-target species in the Serengeti. In: Taylor V, Dunstone N (eds) The exploitation of mammal populations. Chapman and Hall, London, pp 117–146

  • Jolly GM (1969) The treatment of errors in aerial counts of wildlife populations. East Afr Agric For J 34:50–55

    Google Scholar 

  • Klingel H (1969a) The social organisation and population ecology of the plains zebra (Equus quagga). Zool Afr 4:249–263

    Google Scholar 

  • Klingel H (1969b) Reproduction in the plains zebra, Equus burchelli boehmi: behaviour and ecological factors. J Reprod Fertil Suppl 6:339–345

    Google Scholar 

  • Kruuk H (1972) The spotted hyena: a study of predation and social behaviour. University of Chicago Press, Chicago, Ill.

    Google Scholar 

  • Lebreton JD, Millier C (1982) Modèles dynamiques déterministes en biologie. Masson, Paris, p 208

  • Legendre S, Clobert J (1995) ULM, a software for conservation and evolutionary biologists. J Appl Stat 22:817–834

    Article  Google Scholar 

  • Leslie PH (1966) The intrinsic rate of increase and the overlap of successive generations in a population of guillemots (Uria Aalge Pont.). J Anim Ecol 35:291–301

    Google Scholar 

  • Loison A, Festa-Bianchet M, Gaillard JM, Jorgenson JT, Jullien JM (1999) Age-specific survival in five populations of ungulates: evidence of senescence. Ecology 80:2539–2554

    Google Scholar 

  • Maddock L (1979) The “migration” and grazing succession. In: Sinclair ARE, Norton-Griffiths M (eds) Serengeti: dynamics of an ecosystem. University of Chicago Press, Chicago, Ill., pp 104–129

  • Mduma SAR, Sinclair ARE, Hilborn R (1999) Food regulates the Serengeti wildebeest: a 40-year record. J Anim Ecol 68:1101–1122

    Article  Google Scholar 

  • Ménard C, Duncan P, Fleurance G, Georges J-Y, Lila M (2002) Comparative foraging and nutrition of horses and cattle in European wetlands. J Appl Ecol 39:120–133

    Article  Google Scholar 

  • Mills MGL, Shenk TM (1992) Predator-prey relationships: the impact of lion predation on wildebeest and zebra populations. J Anim Ecol 61:693–702

    Google Scholar 

  • Mills MGL, Biggs HC, Whyte IJ (1995) The relationship between rainfall, lion predation and population trends in African herbivores. Wildl Res 22:75–88

    Google Scholar 

  • Moehlman PD (ed) (2002) Equids: zebras, asses and horses. Status survey and conservation action plan. IUCN/SSC Equid Specialist Group. IUCN, Gland, p 190

  • Ogutu JO, Owen-Smith N (2003) ENSO, rainfall and temperature influences on extreme population declines among African savanna ungulates. Ecol Lett 6:412–419

    Google Scholar 

  • Pluhacek J, Bartos L (2000) Male infanticide in captive plains zebra, Equus burchelli. Anim Behav 59:689–694

    Article  PubMed  Google Scholar 

  • Prins HHT (1996) Behaviour and ecology of the African buffalo: social inequality and decision making. Chapman and Hall, London

    Google Scholar 

  • Redfern JV, Grant R, Biggs H, Getz WM (2003) Surface-water constraints on herbivore foraging in the Kruger National Park, South Africa. Ecology 84:2092–2107

    Google Scholar 

  • Schaller GB (1972) The Serengeti lion. University of Chicago Press, Chicago, Ill.

  • Sinclair ARE (1974) The natural regulation of buffalo populations in East Africa. IV. The food supply as a regulating factor, and competition. East Afr Wildl J 12:291–311

    Google Scholar 

  • Sinclair ARE (1977) The African buffalo. A study of resource limitation of populations. University of Chicago Press, Chicago, Ill.

  • Sinclair ARE (1985) Does interspecific competition or predation shape the African ungulate communities? J Anim Ecol 54:899–918

    Google Scholar 

  • Sinclair ARE (1997) Fertility control of mammal pests and the conservation of endangered marsupials. Reprod Fertil Dev 9:1–16

    Article  CAS  Google Scholar 

  • Sinclair ARE, Arcese P (1995) Serengeti II: dynamics, management, and conservation of an ecosystem. University of Chicago Press, Chicago, Ill.

    Google Scholar 

  • Sinclair ARE, Norton-Griffiths M (1979) Serengeti: dynamics of an ecosystem. University of Chicago Press, Chicago

  • Sinclair ARE, Norton-Griffiths M (1982) Does competition or facilitation regulate migrant ungulate populations in the Serengeti? A test of hypotheses. Oecologia 53:364–369

    Google Scholar 

  • Sinclair ARE, Dublin HT, Borner M (1985) Population regulation of Serengeti wildebeest: a test of the food hypothesis. Oecologia 65:266–268

    Google Scholar 

  • Sinclair ARE, Mduma SAR, Arcese P (2000) What determines phenology and synchrony of ungulate breeding in Serengeti? Ecology 81:2100–2111

    Google Scholar 

  • Smuts GL (1976) Reproduction in the zebra mare Equus burchelli antiquorum from the Kruger National Park. Kodoe 19:89–132

    Google Scholar 

  • Smuts GL (1978) Interrelations between predators, prey, and their environment. BioScience 28:316–320

    Google Scholar 

  • Spinage CA (1972) African ungulate life tables. Ecology 53:645–652

    Google Scholar 

  • Treisman M (1975) Predation and the evolution of gregariousness. I. Models for concealment and evasion. Anim Behav 23:779–800

    Google Scholar 

  • Van Wieren SE (1996) Digestive strategies in ruminants and non-ruminants. PhD thesis. Agricultural University, Wageningen

  • Watson RM (1967) The population ecology of the Serengeti wildebeest. PhD thesis. Cambridge University, Cambridge

  • Watson RM (1969) Reproduction of wildebeest, Connochaetes taurinus albojubatus Thomas, in the Serengeti region, and its significance to conservation. J Reprod Fertil [Suppl] 6:287–310

    Google Scholar 

Download references

Acknowledgements

We thank the directors and boards of the Serengeti Wildlife Research Institute and Tanzania National Parks, the park wardens of Serengeti National Park. Without them none of the long-term studies on Serengeti ungulates would have been possible. We thank the many colleagues that have improved the manuscript through their comments on early drafts, particularly N. Owen-Smith, H. Fritz, P. Inchausti, H. Kruuk, H. Klingel and two anonymous referees. This study was supported by the CNRS as part of the France-South Africa Programme International de Coopération Scientifique, Plant-Herbivore Dynamics in Changing Environments.

Author information

Authors and Affiliations

  1. Centre d’Etudes Biologiques de Chizé, CNRS UPR 1934, 79360, Beauvoir-sur-Niort, France

    Sophie Grange & Patrick Duncan

  2. UMR 5558 “Biométrie et Biologie Evolutive”, Université Claude Bernard LYON1, Batiment 711. , 43 Boulevard du 11 novembre 1918, 69622, Villeurbanne Cedex, France

    Jean-Michel Gaillard

  3. Centre for Biodiversity Research, University of British Columbia, 6270 University Boulevard, Vancouver, Canada, V6T 1Z4

    Anthony R. E. Sinclair

  4. USGS, Northern Rocky Mountain Science Center, Forestry Sciences Laboratory, Montana State University, Bozeman, MT 59717-2780, USA

    Peter J. P. Gogan

  5. Department of Ecology, Evolution, and Behavior, University of Minnesota, 1987 Upper Buford Circle, St. Paul, MN 55108, USA

    Craig Packer

  6. Institute of Zoo & Wildlife Research, Alfred-Kowalke-Strasse 17, 10315, Berlin, Germany

    Heribert Hofer & Marion East

Authors
  1. Sophie Grange
    View author publications

    You can also search for this author in PubMed Google Scholar

  2. Patrick Duncan
    View author publications

    You can also search for this author in PubMed Google Scholar

  3. Jean-Michel Gaillard
    View author publications

    You can also search for this author in PubMed Google Scholar

  4. Anthony R. E. Sinclair
    View author publications

    You can also search for this author in PubMed Google Scholar

  5. Peter J. P. Gogan
    View author publications

    You can also search for this author in PubMed Google Scholar

  6. Craig Packer
    View author publications

    You can also search for this author in PubMed Google Scholar

  7. Heribert Hofer
    View author publications

    You can also search for this author in PubMed Google Scholar

  8. Marion East
    View author publications

    You can also search for this author in PubMed Google Scholar

Corresponding author

Correspondence to Sophie Grange.

Appendix

Appendix

Calculations for zebra juvenile survival

Survival rates were estimated from the proportions of successive age-classes in the formulas below. As field observations were not done in the same month each year, we compared only samples obtained in 2 successive years (we included the comparison between January and November in 1994). For example, the yearling survival in 1988 was estimated from the juvenile proportion in the 1987 wet season and the yearling proportion in the 1988 wet season. For foal survival, we calculated the expected number of newborns in one year from the number of reproductive females in the previous year and their fecundity. To estimate first-year survival (Table 10), we compared the expected recruitment to the yearling class with the proportion of yearlings observed in the same year (Table 11) .

Table 10 First-year survival. p a Proportion of adults >5 years old=0.86, SR f adult sex-ratio (female proportion)=0.64, p I proportion of adult females within age-class I, f I female fecundity within age-class I
Full size table
Table 11 Yearling survival
Full size table

Rights and permissions

Reprints and permissions

About this article

Cite this article

Grange, S., Duncan, P., Gaillard, JM. et al. What limits the Serengeti zebra population?. Oecologia 140, 523–532 (2004). https://doi.org/10.1007/s00442-004-1567-6

Download citation

  • Received:

  • Accepted:

  • Published:

  • Issue Date:

  • DOI: https://doi.org/10.1007/s00442-004-1567-6

Keywords

Search

Navigation