Assessment of the proportion and extent of elephant damage on Acacia nigrescens and Sclerocarya birrea in the Punda Maria area in the Kruger National Park

The Kruger National Park has responded to growing concern over the increasing elephant
population by first implementing a population control management strategy through culling and in
recent years, suspending culling and implementing a policy of promoting heterogeneity through
maintaining differential elephant numbers in different areas in the park. The concern stems from
the potential of elephants to change the population structure of certain keystone tree species in the
park drastically, such as Acacia nigrescens and Sclerocarya birrea. This study surveys four sites in
the Punda Maria area and assesses the population structure, damage intensity, and degree of
recovery of over eight hundred A. nigrescens individuals and over one hundred S. birrea
individuals. Almost twenty-five percent of all living A. nigrescens and over eighty-two percent of
S. birrea sampled showed some sign of elephant damage; however, only a small proportion of these
trees showed high levels of intense damage, and the intensity of damage was distributed
differentially across height classes. Also, these species showed a great deal of recovery in the
forms of resprouting after branch damage and bark regrowth after stripping. Large proportions of
damage were recorded in both populations but a very low proportion of this damage was severe. A.
nigrescens and S. birrea both show immense capability to recover. Survival strategies differ
between the two species. Elephants prefer to remove bark from marula trees and in response, these
trees have adapted an ability to repair removed bark efficiently. Complete recovery of bark
damaged areas was commonly noted. Elephants readily break branches of A. nigrescens and in
response, this species resprouts quite readily.