Mollusc fauna of the mangrove root-fouling community at the Colombian Archipelago of San Andres and Old Providence

This paper advances a qualitative and quantitative preliminarycharacterization of the mollusc fauna associated with the submerged rootsof Rhizophora mangle L. in three mangrove areas with differentdegrees of anthropogenic impact in the San Andres (Hooker and HondaBays) and Providence (Old Providence McBean Lagoon National Park)archipelago in the Western Caribbean. The study was carried out during thedry and rainy seasons (July and November, respectively) back in 1998.Samples were taken from 34 submerged roots which were not fixed to thesubstrate. Several physico-chemical parameters were also measured insitu. All molluscs were identified and counted and indexes of speciesrichness, diversity, uniformity, similarity, dominance of species and densityof individuals were calculated. All in all 5,771 individuals belonging to 21species of 17 families were counted. Most of the species were epibenthic,herbivorous and with undifferentiated planctonic larvae, but most of theindividuals were epifaunal and attached as well as filter-feeders withplanctonic larvae. Most individuals were found in juvenile stages. The threesites, under different degrees of anthropogenic impacts, showed relatedvalues of species richness, diversity and abundance, as well as densities ofmollusc taxa in oceanic communities associated with mangrove roots.Further research should be done to find similar responses in accompanyingsignificant groups, such as Crustacea and Polychaeta.[PUBLICATION ABSTRACT]