The early succession of the taxa Annelida, Mollusca and Crustacea on Rhizophora mangle (red mangrove) submerged roots was analyzed using old branches as ground (which were the experimental units) in San Andres Island.The analysis was related to some physico-chemical and environmental variables during 188 days, between November/ 2002 and May/2003, in Hooker and Honda bays.A total of 34,175 individuals in 130 experimental units were counted, where the annelids represented the largest proportion (77.1%) from the whole sample.A dendrogram and a nonmetric multidimensional scaling (NMDS) were constructed for each one of the three studied taxa.The analyses showed a weak similarity between the internal part of the Hooker Bay and the remaining stations.Shannon-Wiener diversity, Pielou evenness, Margalef richness and Simpson predominance indexes were calculated throughout the study; the three first indices showed greater values in Hooker Bay than in Honda Bay, while the predominance index was greater in Bay Honda.There were pioneers organisms such as Spirorbis sp., and transient ones, such as crustaceans, whilst molluscs seemed to need longer periods to settle in.These responses reveal that geomorphological characteristics, presence or absence of freshwater currents, tides and rainfall mainly, as well as anthropic factors can influence the development of these communities.Larval dispersion and the proximity to other ecosystems increase or reduce the populations, and only some organisms, adapted to extreme conditions, settle down and maintain in the area.Under favorable conditions, abundance and species diversity tend to increase.