Protecting Large Trees

Elephants impact large trees– they strip the bark, break branches and uproot the trees. This causes Human: Elephant Conflict, as these iconic large tree species are considered of ecological and aesthetic importance to reserve managers, tourists and landowners.

Hence, since 2004, we have been studying the accumulated impact of elephants on three species of iconic large trees, knob thorn, marula and false marula trees, which are known to be heavily utilized by elephants and therefore of concern to managers and private landowners.

We are researching which mitigation methods could be used to increase the survival rate of large trees. One method uses wire-net protection wrapped around the trunk, which reduces its chance of being bark-stripped by elephants and can significantly increase the survival rates of individual trees.  Wire netting did not affect other types of elephant impact such as branch breaking, stem snapping or uprooting trees. A second mitigation method which may protect the entire tree involves using bee hives as a deterrent – for further information about our bee hive research, see the bees and trees section of the website.

Since 2004, we have been monitoring 3071 individual large trees – half with wire netting, and half with no protective measure, to study the efficacy of wire-net protection methods and to determine survival rate and influence of elephant impact.  As well as any elephant damage, we also record wind toppling, insect attacks, the effects of fire and death due to unknown causes.

Overall we provide information on the effects of elephants as drivers of ecosystem change in relation to indicator species such as large trees. Individual trees are monitored over time to establish rates of change in important landscape features. This information contributes towards improving our knowledge of the ecological processes that promote the sustainable coexistence of elephants, their habitats and people.