Examining Elephant Impact on Tree Populations in Kruger National Park
Katherine Grant, class of 2007 | Major: Environmental Science and Policy (A.B.); minor: Biology | Extracurriular: First Year Advisory Counselor Program Executive Board Member, working at the Center for Latin American and Caribbean Studies, running, singing, Students to Unite Duke, Zeta Tau Alpha | Home: Mystic, CT
In Katherine’s words:
The African elephant (Loxidonta africana) is one of the many charismatic mammal species present in Kruger National Park in South Africa. Many publications and textbooks refer to elephants as “environmental engineers” because they play a major role in shaping savanna landscape, community, and population ecology.
During the spring semester of 2006, I traveled to South Africa through the Duke/Organization for Tropical Studies Study Abroad Program. While in South Africa, I completed two independent field study projects with the help of other students. We designed these projects ourselves, collected data in Kruger, wrote scientific reports, and presented our results at a symposium in front of Kruger Park scientists. Both of my projects focused on the demography of certain tree species and the impact of elephants on tree populations in Kruger National Park.
During my first project, my group and I examined the impact of elephants on marula trees in the Pretorioskop region in southern KNP by conducting surveys inside and outside a roan enclosure. Because the roan enclosure is fenced, no elephants have been in this area for more than forty years. We recorded the height and dbh of trees to help place them into age classes. We also noted tree breakage and stripping due to elephants. We found that there was significantly more tree damage outside the roan enclosure than inside the roan enclosure. We also found significantly fewer young trees outside the roan enclosure than inside the roan enclosure. Our study showed that elephant utilization of the marula tree may have a great impact on the demography of marula populations.
In my second project, my group and I studied the demography of three species of Commiphora (C. mollis, C. edulis, and C. africana) and Sterculia rogersii in the Pafuri region in northern Kruger National Park.
Going to South Africa was a great opportunity to travel and conduct scientific field studies. For my ‘graduation with distinction’ project I am studying elephant management in protected areas in South Africa. After researching the effects of elephants on plant populations, it has been interesting for me to try to determine how managers address the problem of rapidly growing elephant densities.
