GREATER KRUGER - The damage elephants can inflict on the environment is huge. It is not damage in the usual sense, but literally changes the ecosystem. With their large body size, high population densities, and their ability to push down trees, they are able to open up densely vegetated habitats, and other species benefit from having access to food sources which would otherwise be out of reach.
It is just that sometimes it would help if the elephants could be a bit more selective!
Long-term studies on the effects of elephants on the marula trees in the Greater Kruger region have revealed severe elephant-related damage to adult trees through ring-barking, pruning and toppling of trees. Marula trees are important for many reasons. It is an ecologically important tree species in South Africa, providing food, habitat and shade for a variety of species. It also provides a source of income locally in our area, as the fruits are harvested annually by the local communities and made into preserves or beer, or sold as the raw material for the iconic Amarula liqueur. Therefore, it is essential to develop methods to protect these trees from the ravages of elephants without harming either the elephants or the environment, and so to preserve biodiversity in this region.
Research in Kenya shows that elephants will actively avoid the African honeybee evading trees with live beehives, crop fields surrounded by beehive fence-lines, and even moving away from the playback recordings of swarming honeybees. These findings have opened up the possibility of using active beehives as a deterrent to keep the elephants away from mature marula trees in the Greater Kruger region.
African honeybees are also important pollinators of marula trees, as well as other savannah tree species. With concerns over a global honeybee population decline, it is important to establish honeybee colonies across protected areas that will assist in the pollinating of large trees.
Dr Michelle Henley of Elephants Alive (http://elephantsalive.org/), together with the University of Witwatersrand, will be carrying out a project to assess if active beehives can be used to deter elephants from damaging adult marula trees. The results of this method will then be compared to the wire-netting of trees, to prevent ring barking damage caused by elephants. To gain more scientific evidence of whether the method is working, theproject will test whether the elephants exhibit elevated stress hormones when in the presence of beehives. This will be performed through analysis ofcertain components of their faeces, a method which has been previously used to assess elevated stress hormones in African elephants. Elevated stress hormone levels may provide confirmation that elephants are changing their behaviours when in the presence of beehives, which could be a further indication that beehives are working as a method for modifying their behaviour.
Source: Research proposal, Robin Cook, University of Witwatersrand