The effect of substrate type on microscopic epibiont community diversity: A shoreline study from the Sea of Japan at Niigata, Japan

Abstract

Abstract Microscopic epibionts are an important component of intertidal ecosystems. Shortage of space drives these organisms to settle and grow on body/shell surfaces of intertidal organisms. In this study we test the hypothesis that epibiont communities vary significantly between shells belonging to different invertebrate species, and between natural shells and plastic surfaces. Epibiont community variations are caused by differences in shell size, roughness and mobility of the host organisms. Epibionts growing on fifteen different species belonging to Gastropoda, Bivalvia, Polyplacophora and Echinoidea, as well as plastic objects were collected from a rocky shore of the Sea of Japan at Niigata. Most epibionts collected were diatoms, and the highest epibiont density was recorded on the surfaces of the limpet Cellana toreuma. The results showed epibiont species richness, diversity and density varied significantly with the host characteristics such as mobility, shell size and shell roughness. The shells of sessile organisms with large and smooth surfaces had a higher epibiont density, species richness and diversity than did shells of mobile organisms with small and rough shell surfaces. To conclude, epibiont species composition varies significantly between basibiont species, shell morphology, shell size, shell roughness, month of sampling and the mobility of the host.