Coral reefs throught the world's tropical areas are presently threatened by man-made and natural influences including increased turbidity and siltation, abnormal inputs of nutrients and organic matter, pollution by toxic materials, thermal stress, changes in water circulation and wave exposure, direct physical damage and by selective removal of organisms. Most tropical areas with extensive coral reefs are located in underdeveloped countries with very little financial resources and poor land management practices. As the human population increases, needs for housing and food increase resulting in extensive deforestation and erosion. These practices have increased the amount of terrigenous sediments that reach coastal and nearshore areas. As a result of this, many tropical nearshore reefs have received higher terrigenous sediment and nutrient loads with a consequent loss of coral cover and decreased coral species diversity (Acevedo 1988; Hallock and Schlager; 1986 ). The most striking effect of increased terrigenous sediment influx results in a shifting of zonation and an upward migration of depth zones (Hallock and Schlager; 1986). Light reduction is a major impact resulting from excess sedimentation and both loss of coral cover and a shift to slower growing coral species is commonly observed (Morelock et. al; 1979). Other detrimental effects of increased sedimentation are: partial or total burial of coral colonies, bleaching, increased bacterial activity on coral surfaces (Hodgson; 1989) and inhibition of coral larvae settlement (Wells; 1957). Although corals do not account for the major fraction of total reef community biomass, when they die, the community degenerates