In 2009, these numbers changed to 800 for harvesting, 1 700 for processing and 100 for aquaculture. Segment 4S1 (vessels > 12 m), 4S2 (boats up to 12 m), 4S3 (vessels 12-40 m) and 4S4 (boats up to 12 m). Biomass of the spawning stock of Baltic herring in the coastal Baltic Sea increased by 5% in 2008.