A shallow subtidal area in the northern Wadden Sea was monitored for sediment parameters and macrobenthic fauna using stratified random sampling of a grid of 50 sampling positions. Samples were collected with a Reineck-type box-corer of 0.02 m² surface area, macrobenthos (sieved through 1 mm square meshes and fixed in buffered formalin solution) was counted, identified to species level, and the size of hard-shelled individuals measured. This dataset contains the size measurements of 259 individuals from the 2017 sampling.