Long Term Monitoring of Coral Reefs in Great Lameshur Bay St. John, U.S.V.I.

Witman, Jon

Coral reefs are perhaps the most valuable marine resources in the tropics because they provide critical habitat structure for many species of commercially important fishes and because they are centers of biotic diversity. In recent years the structural integrity of the framework of Caribbean reefs has been severely threatened by diseases and environmental perturbations. For example, white band disease eliminated many elkhorn corals, Acropora palmata, from the fore-reef off StCroix (Gladfelter 1982), and the bleaching phenomenon of 1987 caused total or partial mortality of corals, sponges, and gorgonians across the Caribbean (Williams et. al. 1987). Excess sedimentation from construction activities may kill more corals than any other anthropogenic pollutants. Such recent perurbations to coral reefs in the Caribbean has emphasized the need to assess the cunent "health" of coral populations to determine whether the reefs are declining or simply undergoing normal changes. However the detection of human-induced changes in coral reefs requires that impact effects be separated from normal inter-annual fluctuations in the growth, recruitment and mortality of corals. At present our understanding of natural fluctuations in coral reef communities is strictly limited by the lack of long-term studies of reef community dynamics.