Effects of elephants and goats on the Kaffrarian succulent thicket of the eastern Cape, South Africa.
Abstract
The effects of defoliation by wild herbivores (mostly elephants) or domestic ungulates (mostly goats) on Kaffrarian succulent thicket, dominated by the tree-succulent Portulacaria afra, were compared using surveys inside and outside the Addo Elephant National Park. Both elephants and goats reduced canopy cover and increased shrub density compared with ungrazed areas, while goats reduced the number of dominant shrub species/quadrat. Replacing elephants with goats changed the shrub community to one dominated by small, unpalatable shrubs with a few scattered umbrella-shaped trees. Goats reduced the percentage frequency of P. afra by 40% and its density by 71%, causing a 91% decrease in the total area rooted by this species. Implications for land management are discussed.