STATUS OF KENYAN CORAL-REEFS

The existence of four marine parks and numerous reefs experiencing intense human resource use has provided the opportunity for a number of studies that have helped increase the understanding of human impacts on Kenyan reefs. Studies indicate that the removal of finfish is having the largest impact on unprotected reefs and has a number of secondary and tertiary effects on other faunal groups and ecological processes. A high abundance of sea urchins in unprotected reefs results from reductions in sea urchin predators-largely due to overfishing. High sea urchin populations are associated with reefs with lower coral cover, topographic complexity, and reduced calcium carbonate deposition rates. One reef was converted into a marine park during the study period (1987 to 1994) and showed rapid recovery in coral cover and fish abundance and diversity. Some species of gastropod appear to be affected by shell collecting, but the total fauna seems more affected by removal of their finfish predators. River sediment discharges and eutrophication are of secondary importance but are not severe as yet; they are difficult to distinguish from natural variations over geologic history. We briefly suggest alternative management and research actions for Kenyan reefs on the basis of their existing management.