The effect of Hurricane Allen on the Bellairs fringing reef,Barbados

On August 4, 1980 Hurricane Allen damaged the northern fringing reef located just offshore from the Bellairs Research Institute of McGill University on the west coast of Barbados. During the summer and one winter month of 1981 a resurvey of the reef was done and the results were compared with a similar survey made in 1974. On a reefal scale the changes in the proportion of substrates before and after Hurricane Allen were statistically significant for all substrates and species with the exception of Millepora spp. Among the corals, Porites porites has been most affected by the catastrophe: its coverage was reduced by 96%. The other corals (Siderastrea sidera, Porites astreoides, Montastrea annularis, and Agaricia agaricites) were reduced by 75 to 25%. Onshore transport is suggested by the high abundance of Acropora cervicornis (20%) and Madracis mirabilis (30%) in the rubble on the fringing reef (the former only grows seaward of the reef). Offshore transport is suggested by the relatively poor representation of Porites porites (32%) in the rubble. Shannon-Weaver diversity indices of the corals dropped from 1.61 to 1.26. The changes in diversity are best explained by the intermediate disturbance hypothesis.