Hostname: page-component-586b7cd67f-rcrh6 Total loading time: 0 Render date: 2024-11-28T01:11:05.572Z Has data issue: false hasContentIssue false
  • English
  • Français

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: [email protected]
Get access Rights & Permissions [Opens in a new window]

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

Access options

Get access to the full version of this content by using one of the access options below. (Log in options will check for institutional or personal access. Content may require purchase if you do not have access.)

References

LITERATURE CITED

BAXTER, P. W. J. & GETZ, W. M. 2008. Development and parameterization of a rain- and fire-driven model for exploring elephant effects in African savannas. Environmental Modelling and Assessment 13:221–242.CrossRefGoogle Scholar
BELL, S. M. 2003. Mortality rates of riparian woodland trees on the Linyanti River, northern Botswana. M.Sc. research report, University of the Witwatersrand, Johannesburg.Google Scholar
BUECHNER, H. K. & DAWKINS, H. C. 1961. Vegetation change induced by elephants and fire in Murchison Falls National Park, Uganda. Ecology 42:752–766.CrossRefGoogle Scholar
CHAFOTA, J. 2007. Factors governing selective impacts of elephants on woody vegetation. Ph.D. thesis, University of the Witwatersrand, Johannesburg.Google Scholar
CHAMMAILLE-JAMMES, S., FRITZ, H., VALEIX, M., MURINDAGOMO, F. & CLOBERT, J. 2008. Resource availability, aggregation and direct density dependence in an open context: the local regulation of an African elephant population. Journal of Animal Ecology 77:135–144.CrossRefGoogle Scholar
CHILDES, S. L. & WALKER, B. H. 1987. Ecology and dynamics of the woody vegetation on Kalahari sands in Hwange National Park. Vegetatio 72:111–128.CrossRefGoogle Scholar
CRAIG, G. C. 1990. Present population and distribution of elephants in northern Botswana. Pp. 16–18 in Hancock, P. (ed.). The future of Botswana's elephants. Gaborone, Botswana.Google Scholar
CROZE, H. 1974. The Seronera bull problem II. The trees. East African Wildlife Journal 12:29–47.CrossRefGoogle Scholar
DE BEER, Y., KILIAN, W., VERSVELD, W. & VAN AARDE, R. J. 2006. Elephants and low rainfall alter woody vegetation in Etosha National Park, Namibia. Journal of Arid Environments 64:412–421.CrossRefGoogle Scholar
DUBLIN, H. T., SINCLAIR, A. R. E. & MCGLADE, J. 1990. Elephants, fire as causes of multiple stable states in the Serengeti-Mara woodlands. Journal of Animal Ecology 59:1147–1164.CrossRefGoogle Scholar
FIELD, C. R. 1971. Elephant ecology in the Queen Elizabeth National Park, Uganda. East African Wildlife Journal 9:99–123.CrossRefGoogle Scholar
GIBBS RUSSELL, G. E., GERMISHUIZEN, G., HERMAN, P., OLIVIER, P., PEROLD, S. M., REID, C., RETIEF, E., SMOOK, L., VAN ROOY, J. & WELMAN, W. G. 1984. List of species of southern African plants. Botanical Research Institute, Pretoria. 144 pp.Google Scholar
GIBSON, D. ST. C, CRAIG, G. C. & MASOGO, R. M. 1998. Trends of elephant population in northern Botswana from aerial survey data. Pachyderm 25:14–27.Google Scholar
GILSON, L. 2004. Evidence of hierarchical patch dynamics in an East African savanna? Landscape Ecology 19:883–894.CrossRefGoogle Scholar
HENDRICHS, H. 1971. Freilandsbeobachtungen zum Sozialsystem der Afrikanischer Elefanten. Pp. 77–173 in Hendrichs, H. (ed.). Dikdik und Elefanten. R. Piper Verlag, Munich.Google Scholar
HIGGINS, S. J., BOND, W. J. & TROLLOPE, W. S. W. 2000. Fire, resprouting and variability: a recipe for grass–tree coexistence in savanna. Journal of Ecology 88:213–229.CrossRefGoogle Scholar
HOLDO, R. M. 2006. Elephant herbivory, frost damage and topkill in Kalahari sand woodland savanna trees. Journal of Vegetation Science 17:509–518.CrossRefGoogle Scholar
HOLDO, R. M. 2007. Elephants, fire, and frost can determine community structure and composition in Kalahari woodlands. Ecological Applications 17:558–568.CrossRefGoogle ScholarPubMed
LAWS, R. M. 1970. Elephants as agents of habitat and landscape change in East Africa Oikos 21:1–15.CrossRefGoogle Scholar
LAWS, R. M., PARKER, I. S. C. & JOHNSTONE, R. C. B. 1975. Elephants and their habitats. The ecology of elephants in North Bunyoro, Uganda. Oxford, Clarendon Press. 376 pp.Google Scholar
LEWIS, D. L. 1991. Observations of tree growth, woodland structure and elephant damage on Colophospermum mopane in Luangwa Valley, Zambia. African Journal of Ecology 29:207–221.CrossRefGoogle Scholar
MAPAURE, I. N. & CAMPBELL, B. M. 2002. Changes in miombo woodland cover in and around Sengwa Wildlife Research Area, in relation to elephants and fire. African Journal of Ecology 40:212–219.CrossRefGoogle Scholar
MIDGLEY, J. J., BALFOUR, D. & KERLEY, G. I. H. 2005. Why do elephants damage savanna trees? South African Journal of Science 101:213–215.Google Scholar
MOSUGELO, D. K., MORE, S. R., RINGROSE, S. & NELLEMANN, C. 2002. Vegetation changes during a 36-year period in northern Chobe National Park, Botswana. African Journal of Ecology 40:232–240.CrossRefGoogle Scholar
PIENAAR, U. D. E. V., VAN WYK, P. & FAIRALL, N. 1966. An aerial census of elephant and buffalo in the Kruger National Park, and the implications thereof on intended management schemes. Koedoe 9:40–107.CrossRefGoogle Scholar
REMMERT, H. 1991. The mosaic cycle of ecosystems – an overview. Pp. 1–21 in Remmert, H. (ed.). The mosaic-cycle concept of ecosystems. Springer-Verlag, New York.CrossRefGoogle Scholar
SPINAGE, C. A. & GUINNESS, F. M. 1971. Tree survival in the absence of elephants in the Akagera National Park, Rwanda. Journal of Applied Ecology 8:723–728.CrossRefGoogle Scholar
TAFANGENYASHA, C. 1997. Tree loss in the Gonarezhou National Park (Zimbabwe) between 1970 and 1983. Journal of Environmental Management 49:355–366.CrossRefGoogle Scholar
VAN DE VIJVER, C. A. D. M., FOLEY, C. A. & OLFF, H. 1999. Changes in the woody component of an East African savanna during 25 years. Journal of Tropical Ecology 15:545–564.CrossRefGoogle Scholar
WACKERNAGEL, A. 1993. Elephants and vegetation: severity, scale and patchiness of impacts along the Linyanti river, Chobe District, Botswana. M.Sc. thesis. University of the Witwatersrand, Johannesburg.Google Scholar
YEATON, R. I. 1988. Porcupines, fires and the dynamics of the tree layer of the Burkea africana savanna. Journal of Ecology 76:1017–1029.CrossRefGoogle Scholar