Man as an Intertidal Predator in Transkei: Disturbance, Community Convergence and Management of a Natural Food Resource

Abstract
The indigenous peoples of Transkei, South Africa, remove shellfish from the shore to supplement their diet. Paired exploited and protected rocky shores were compared in terms of community structure and of the size structures of component species. Relative abundance of algae and sessile, inedible invertebrates is greater, and modal and mean sizes of exploited species are smaller at expoited sites than at protected sites. Disturbance through selective predation increases species richness, in line with the "intermediate disturbance hypothesis", and also leads to community convergence towards a common state. The recovery potential of these systems is high and the resource could best be managed on a "rotational cropping" basis.