MULTISPECIES ALGAL BALLS AND POTENTIALLY IMPRISONED FAUNA - AN UNUSUAL BENTHIC ASSEMBLAGE

Unattached algae which form balls are normally reported as being compo sed of a single species. We report both monospecific algal balls and m ultispecies assemblages with up to four species providing major struct ural components from the Caribbean at Los Roques Archipelago, Venezuel a. Many of the multispecies balls possessed a cavity surrounded by thi ck walls of sediment-impregnated algal filaments. Cavity volume was po sitively related to the length of algal balls. The hollow algal balls were remarkable in that they often contained, and likely imprisoned, a variety of invertebrates, including several species of polychaetes, s ipunculans, molluscs, and crustaceans. Relationships between cavity vo lume and either number or volume of fauna were non-significant. Faunal associates, if in fact imprisoned, are likely to benefit from reduced predation but may be subject to limited food supply, crowding, oxygen deprivation, and limited reproductive opportunities.