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Ecology, management and conservation in natural and modified habitats
RESEARCH ARTICLE

Resource selection by grazing herbivores on post-fire regrowth in a West African woodland savanna

Erik Klop A B , Janneke van Goethem A and Hans H. de Iongh A
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- Author Affiliations

A Institute of Environmental Sciences, Leiden University, PO Box 9518, 2300 RA Leiden, The Netherlands.

B Corresponding author. Present address: Thorbeckestraat 160, 6702 BW Wageningen, The Netherlands. Email: eklop@cs.com

Wildlife Research 34(2) 77-83 https://doi.org/10.1071/WR06052
Submitted: 13 May 2006  Accepted: 2 March 2007   Published: 24 April 2007

Abstract

The preference of grazing herbivores to feed on grass regrowth following savanna fires rather than on unburnt grass swards is widely recognised. However, there is little information on which factors govern patterns of resource selection within burnt areas. In this study, we attempted to disentangle the effects of different habitat and grass sward characteristics on the utilisation of post-fire regrowth by nine species of ungulates in a fire-dominated woodland savanna in north Cameroon. We used resource-selection functions based on logistic regression. Overall, the resource-selection functions identified the time elapsed since burning as the most influential parameter in determining probability of use by ungulates, as most species strongly selected swards that were recently burned. This pattern might be related to nutrient levels in the grass sward. In addition, most species selected areas with high grass cover and avoided grass swards with high amounts of dead stem material. This is likely to increase bite mass and, hence, intake rates. The avoidance of high tree cover by some species may suggest selection for open areas with good visibility and, hence, reduced risk of predation. Body mass seemed to have no effect on differential selection of post-fire regrowth, irrespective of feeding style.


Acknowledgements

This study was supported by the Directoraat Generaal Internationale Samenwerking of the Dutch government and the Institute of Environmental Sciences of Leiden University. In Cameroon we were greatly assisted by many people, most notably Stephen van der Mark, Assan Gomse, Kadri, Moussa, and Amadou Yadji. Marjan van de Weg did an excellent job in monitoring grass quality. Herbert Prins and Helias Udo de Haes provided valuable comments on earlier drafts of this paper. To all these people and organisations we are immensely grateful.


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