The effect of insects on elephant-induced tree damage within a small, fenced reserve in South Africa.

Abstract

African savanna elephants (Loxodonta africana) have been recognised as ecosystem engineers, where their feeding habits have been shown to alter landscapes. Within small, fenced reserves, studies exploring elephant damage on trees and their recovery have overlooked secondary damages that could be contributing to tree mortality. The aim of this study is to assess the significance of both elephant damage and secondary damage, and the subsequent tree recovery. We identified secondary damage as insects and considered wood borers and termites in this study. This was conducted in in the small fenced Karongwe Private Game Reserve (KPGR), South Africa. We analysed the level of damage, recovery and insect presence using vegetation transects, where all trees ≥2 m in height were surveyed (n=1278 trees). Forty tree species were recorded, with 5 species accounting for 77% of the dataset and used for further analysis. Termites were found to be more likely to colonise damaged trees without signs of recovery. However, wood borers were more likely to colonise damaged trees showing signs of recovery. Termites and wood borer presence on damaged trees was not dependent on tree height. We suggest carefully considering management approaches for elephant-induced termite and wood borer damage on trees.