A transect of 30 sm (roughly 60 km) perpendicular to the coastline of the island of Sylt was sampled 4 times between October 2001 and September 2002. Sampling sites (n=21) were regularly spaced along the transect. Two replicate box corer samples were collectet per site and sampling date, sieved (mesh width 1 mm), and preserved in buffered formaldehyde solution. Individuals were determined to species level and counted, abundance is given as individuals per core (0.02 m²).