Impacts of recreational SCUBA diving on coral communities of the Caribbean island of Grand Cayman

The impact of recreational SCUBA diving on coral reefs of the Cayman Islands, British West Indies, was assessed from 63 10-m video transects, filmed on reefs in the West Bay area of Grand Cayman. Three high use and three low use dive sites were sampled at distances of c. 15, 55 and 200 m from mooring buoys, in addition to three sites where no diving occurs. Both diver numbers and distance from buoys were found to show highly significant (P<0.01) effects on hard coral cover and cover of the major reef-building coral, Montastrea annularis. Diver numbers also increased the amount of dead coral and coral rubble. Relative to overall hard coral cover, the proportion of massive corals was smallest at heavily dived sites, but there was a larger proportion of Agaricia spp. corals, dead coral and coral rubble at these sites. Our findings suggest the need for a new management approach if the Islands are to conserve the ecological and aesthetic qualities of their most popular dive sites. (C) 2001 Elsevier Science Ltd. All rights reserved.