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Episodic severe damage to canopy trees by elephants: interactions with fire, frost and rain

Published online by Cambridge University Press:  01 May 2009

Jonas Chafota  and
Norman Owen-Smith
Jonas Chafota
Affiliation:
School of Animal, Plant and Environmental Sciences, University of the Witwatersrand, Wits 2050, South Africa
Norman Owen-Smith*
Affiliation:
School of Animal, Plant and Environmental Sciences, University of the Witwatersrand, Wits 2050, South Africa
*
2Corresponding author. Email: Norman.Owen-Smith@wits.ac.za
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Extract

Elephants (Loxodonta africana (Blumenbach 1797)) can have a major transforming effect on savanna structure through felling, debarking or uprooting trees (Dublin et al. 1990, Laws 1970, Mapaure & Campbell 2002). However, it is difficult to separate their influence from that of other causes of tree mortality, including wind storms (Spinage & Guinness 1971), drought (Lewis 1991, van de Vijver et al. 1999), fire (Higgins et al. 2000), and in some situations frost (Childes & Walker 1987, Holdo 2006), especially when interactions among them may occur (de Beer et al. 2006, Laws et al. 1975, Pienaar et al. 1966). Furthermore, the consequences for woodland dynamics depend on the size classes of the trees affected, as well as on how the disturbance is concentrated in time and space. Mortality of canopy trees has a much greater and longer-lasting impact than losses among the regenerating stages of these trees. However, the consequences may be less adverse for ecosystem function and biodiversity if the disturbing effects are locally concentrated, generating a patch mosaic of stands at different stages of regeneration (Remmert 1991).

Keywords

Botswanaelephant impactsepisodic disturbancesLoxodonta africanapatch mosaicsavanna woodlandstree mortality
Type
Short Communication
Information
Journal of Tropical Ecology , Volume 25 , Issue 3 , May 2009 , pp. 341 - 345
Copyright
Copyright © Cambridge University Press 2009

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References

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