Efficiency of particle retention in 13 species of suspension feeding bivalves

Abstract

Abstract The retention efficiency of 13 species of suspension feeding bivalves has been determined by analysing the particle size distribution in the inhalant and exhalant water currents using a Coulter electronic particle counter. The bivalves were held in aquaria under conditions very similar to their natural environment. It is shown that 11 species, Cardium echinatum, Cardium edule, Modiolus modiolus, Mytilus edulis, Musculus niger, Cultellus pellucidus, Arctica islandica, Ostera edulis, Hiatella striata, Mya arenaria and Venerupis pullastra, which all possess eu-latero-frontal cirri completely retain particles above 1 μm. Particles down to 1 /Lm were in most cases efficiently retained. The retention efficiency in Pecten opercularis and Pecten septemradiatus both lacking the eu-latero-frontal ciliary tract decreases below 7 μm and reaches only 20 % at 1 μm.