Experimental evidence that livestock grazing intensity affects cyclic vole population regulation processes

Nacho Villar, Thomas Cornulier, Darren Evans, Robin Pakeman, Steve Redpath, Xavier Lambin*

*Corresponding author for this work

Research output: Contribution to journalArticle

11 Citations (Scopus)
4 Downloads (Pure)

Abstract

Grazing by domestic ungulates may limit the densities of small herbivorous mammals that act as key prey in ecosystems. Whether this also influences density dependence and the regulation of small herbivore populations, hence their propensity to exhibit multi-annual population cycles, is unknown. Here, we combine time series analysis with a large-scale grazing experiment on upland grasslands to examine the effects of livestock grazing intensity on the population dynamics of field voles (Microtus agrestis). Using log-linear modelling of replicated time series under different grazing treatments, we show that increased sheep densities weaken delayed density dependent regulation of vole population growth, hence reducing the cyclicity in vole population dynamics. While population regulation is commonly attributed to both top-down and bottom up processes, our results suggest that regulation of cyclic vole populations can be disrupted by the influence of another grazer in the same trophic level. These results support the view that ongoing changes in domestic grazing intensity, by affecting small mammal dynamics, can potentially have cascading impacts on higher trophic levels, and strongly influence the dynamics of upland grassland systems.

Original languageEnglish
Pages (from-to)55-61
Number of pages7
JournalPopulation Ecology
Volume56
Issue number1
Early online date8 Sep 2013
DOIs
Publication statusPublished - Jan 2014

Keywords

  • density dependence
  • field vole microtus agrestis
  • grasslands
  • herbivory
  • population cycles
  • ungulate grazing
  • density-dependence
  • predation
  • dynamics
  • impact
  • fluctuations
  • communities
  • ecosystems
  • sheep

Cite this

Experimental evidence that livestock grazing intensity affects cyclic vole population regulation processes. / Villar, Nacho; Cornulier, Thomas; Evans, Darren; Pakeman, Robin; Redpath, Steve; Lambin, Xavier.

In: Population Ecology, Vol. 56, No. 1, 01.2014, p. 55-61.

Research output: Contribution to journalArticle

Villar, Nacho ; Cornulier, Thomas ; Evans, Darren ; Pakeman, Robin ; Redpath, Steve ; Lambin, Xavier. / Experimental evidence that livestock grazing intensity affects cyclic vole population regulation processes. In: Population Ecology. 2014 ; Vol. 56, No. 1. pp. 55-61.
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