Dataset with abundance and growth data of the western Baltic spring spawning herring in the main spawning area Greifswald Bay. The yearly survey is carried out by the Thünen Institute of Baltic Sea Fisheries once per week during the herring spawning season from March to June. The survey provides the base for an annual recruitment index (N20) used for the assessment of this herring stock. WGIPS is the ICES group responsible for this dataset.