REPRODUCTIVE CHARACTERISTICS OF THE POLYMORPHIC CARIBBEAN REEF BUILDING CORAL MONTASTREA-ANNULARIS .2. FECUNDITY AND COLONY STRUCTURE

We studied reproductive characteristics of 3 Montastrea annularis (Ellis & Solander) morphotypes (viz.'Bumpy', 'Massive' and 'Columnar'; Van Veghel & Bak 1993, Mar.Ecol. Prog. Ser. 92: 255-265) by dissecting about 2450 polyps in the reproductive seasons of 1991 and 1992. Fecundity, number of gonads per polyp, and fertility were found to be significantly different between the studied morphotypes (ANOVA, p < 0.001), ranking from high to low in Bumpy, Massive, and Columnar morphotypes. Gonads as percent of total biomass also varied, but were not significantly different for Bumpy (29.7 %) versus Massive (22.0 %) and Columnar (20.9 %) morphotypes. Columnar colonies with interconnected living tissue larger than 50 cm2 were already fully reproductive whereas in other morphotypes fecundity was significantly (ANOVA, p < 0.001) reduced in colonies smaller than 300 cm2. Significant differences (ANOVA, p < 0.05) in fecundity occurred between 2 consecutive years for the Massive morph. On a geographic scale, fecundity of M. annularis populations on Curacao was 5 to 14 times lower than in Puerto Rico. Coral species with comparable reproductive strategy all had higher fecundities than M. annularis in this study. Fecundity and reproductive traits in M. annularis appear to correlate with colony morphology.