LONG-TERM CHANGES ON CORAL-REEFS IN BOOMING POPULATIONS OF A COMPETITIVE COLONIAL ASCIDIAN

A long-term study of the common coral reef spatial competitor Trididem num solidum (van Name), a benthic colonial ascidian, showed a 900 % in crease in densities along the 84 km of hinging reef in Curacao over 15 yr. The pattern of distribution along the coast did not change signif icantly and showed long-term effects of philopatry. This pattern relat es to limited dispersal potential and the impact of the clonal ecologi cal strategy of this modular organism. All hard reef substrata were ov ergrown but between 1978 and 1993 there was a significant increase in the number of ascidian colonies overgrowing dominant scleractinian cor als such as Montastrea annularis.