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The utilization of large savanna trees by elephant in southern Kruger National Park

Published online by Cambridge University Press:  01 May 2008

Graeme Shannon*
Affiliation:
Amarula Elephant Research Programme, School of Biological and Conservation Sciences, Westville Campus, University of KwaZulu-Natal, Private Bag X54001, Durban, 4000, South Africa
Dave J. Druce
Affiliation:
Amarula Elephant Research Programme, School of Biological and Conservation Sciences, Westville Campus, University of KwaZulu-Natal, Private Bag X54001, Durban, 4000, South Africa
Bruce R. Page
Affiliation:
Amarula Elephant Research Programme, School of Biological and Conservation Sciences, Westville Campus, University of KwaZulu-Natal, Private Bag X54001, Durban, 4000, South Africa
Holger C. Eckhardt
Affiliation:
Scientific Services, Kruger National Park, Box 106, Skukuza, 1350, South Africa
Rina Grant
Affiliation:
Scientific Services, Kruger National Park, Box 106, Skukuza, 1350, South Africa
Rob Slotow
Affiliation:
Amarula Elephant Research Programme, School of Biological and Conservation Sciences, Westville Campus, University of KwaZulu-Natal, Private Bag X54001, Durban, 4000, South Africa
*
1Corresponding author. Email: graemeshannon@lycos.co.uk

Abstract:

Elephant are believed to be one of the main ecological drivers in the conversion of savanna woodlands to grassland. We assessed the impacts of elephant on large trees (≥5 m in height) in the southern section of the Kruger National Park. Tree dimensions and utilization by elephant were recorded for 3082 individual trees across 22 transects (average length of 3 km and 10 m wide). Sixty per cent of the trees exhibited elephant utilization and 4% were dead as a direct result of elephant foraging behaviour. Each height class of tree was utilized in proportion to abundance. However, the size of the tree and the species influenced the intensity of utilization and foraging approach. Sclerocarya birrea was actively selected for and experienced the highest proportional utilization (75% of all trees). Interestingly, the proportion of large trees that were utilized and pushed over increased with distance from permanent water, a result which has implications for the provision of water in the KNP. We conclude that mortality is likely to be driven by a combination of factors including fire, drought and disease, rather than the actions of elephant alone. Further investigation is also required regarding the role of senescence and episodic mortality.

Type
Research Article
Copyright
Copyright © Cambridge University Press 2008

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