Biodiversity and Conservation

, Volume 18, Issue 9, pp 2327–2342 | Cite as

Plant community response to loss of large herbivores: comparing consequences in a South African and a North American grassland

  • Catherine E. BurnsEmail author
  • Scott L. Collins
  • Melinda D. Smith
Original Paper


Loss of biodiversity poses one of the greatest threats to natural ecosystems throughout the world. However, a comprehensive understanding of the impacts of species losses from upper trophic levels is still emerging. Here we compare the impacts of large mammalian herbivore species loss on grassland plant community structure and composition in a South African and North American grassland. Herbaceous plant communities were surveyed at sites without large mammalian herbivores present and at sites with a single species of herbivore present in both locations, and additionally at one site in South Africa with multiple herbivore species. At both the North American and South African locations, plant communities on sites with a single herbivore species were more diverse and species rich than on sites with no herbivores. At the multi-herbivore site in South Africa, plant diversity and richness were comparable to that of the single herbivore site early in the growing season and to the no herbivore site late in the growing season. Analyses of plant community composition, however, indicated strong differences between the multi-herbivore site and the single and no herbivore sites, which were more similar to each other. In moderate to high-productivity ecosystems with one or a few species of large herbivores, loss of herbivores can cause a significant decrease in plant diversity and richness, and can have pronounced impacts on grassland plant community composition. In ecosystems with higher herbivore richness, species loss may also significantly alter plant community structure and composition, although standard metrics of community structure may obscure these differences.


Biodiversity Community structure Diversity Herbivory Richness Savanna Species loss 



Many thanks to the staff of Kruger National Park—most notably H Biggs, D Pienaar, A Potgieter, N Zambatis, and N Govender—for their support of this research and for their faithful maintenance of the Experimental Burn Plots in the Satara region of the park. Thanks also to the staff of the Konza Prairie Biological Station for their support of this research. J Bowers, G Buis and M Kruger provided supplementary information useful in establishing the characteristics and history of each study location. L Calabrese, R Fynn, J Heisler, A Knapp, J Nippert, L Zeglin, and A Zinn assisted in the data collection. G Overbeck, R Fynn and two anonymous reviewers provided helpful feedback during manuscript preparation. This research was supported by National Science Foundation grants DEB-0516145 to MDS and DEB-0516155 to SLC. C Burns was supported in part by a Brown Postdoctoral Research Fellowship at Yale University.


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Copyright information

© Springer Science+Business Media B.V. 2009

Authors and Affiliations

  • Catherine E. Burns
    • 1
    • 2
    Email author
  • Scott L. Collins
    • 3
  • Melinda D. Smith
    • 1
  1. 1.Department of Ecology & Evolutionary BiologyYale UniversityNew HavenUSA
  2. 2.Department of Wildlife EcologyUniversity of MaineOronoUSA
  3. 3.Department of Biology, MSC03-2020University of New MexicoAlbuquerqueUSA

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