Integrating herbivore assemblages and woody plant cover in an African savanna to reveal how herbivores respond to ecosystem management

PLoS One. 2022 Aug 31;17(8):e0273917. doi: 10.1371/journal.pone.0273917. eCollection 2022.

Abstract

African savannas are experiencing anthropogenically-induced stressors that are accelerating the increase of woody vegetation cover. To combat this, land managers frequently implement large-scale clearing of trees, which can have a cascading influence on mammalian herbivores. Studies rarely focus on how differences in woody cover influence the herbivore assemblage, making it difficult to assess how aggressive measures, or the lack of management, to counteract increasing woody cover affect the local composition and biodiversity of herbivores. We address this knowledge gap by applying a model-based clustering approach to field observations from MalaMala Game Reserve, South Africa to identify multiple herbivore-vegetation 'configurations,' defined as unique sets of herbivore assemblages (i.e., groups of herbivores) associated with differing woody plant covers. Our approach delineated how tree-clearing influences the distribution and abundance of the herbivore community in relation to surrounding savanna areas, which represent a natural mosaic of varying woody cover. Regardless of season, both intensively managed areas cleared of trees and unmanaged areas with high tree cover contained configurations that had depauperate assemblages of herbivores (low species richness, low abundance). By contrast, habitats with intermediate cover of woody vegetation had much higher richness and abundance. These results have substantial implications for managing African savannas in a rapidly changing climate.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Ecosystem*
  • Grassland
  • Herbivory*
  • Mammals
  • Trees
  • Wood

Grants and funding

M.H.S - 120670. The National Research Foundation of South Africa. https://www.nrf.ac.za M.H.S. Claude Leon Foundation Postdoctoral Fellowship. https://www.leonfoundation.co.za/ K.S - 116665. The National Research Foundation of South Africa.https://www.nrf.ac.za The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.