Factors influencing the spatial variation in fish and macrocrustacean communities in the surf zone of sandy beaches in Belgium

An inventory of fish and epibenthic macrocrustaceans of the surf zones of sandy beaches along the Belgian coast was constructed. The surf zones were sampled intensively with a 2-m beam trawl in April May 1996 (12 stations) and 26 species were recorded belonging to caridean shrimps (4), brachyuran crabs (5), cephalopods (1) arid fish (16). The brown shrimp Crangon crangon dominated almost all samples (>80%). Total densities exceeded several times 250 ind 100 m(-2) and 10 ind 100 m(-2) if C. crangon was excluded. An east - west distinction as found in other (epi)benthic studies in deeper waters of the Belgian coast, was not found in the surf zone during this study. Spatial variation was mainly correlated with local characteristics such as turbidity of the water and the morphodynamic features of both the beach and the adjacent subtidal area.