1997 ICES coordinated acoustic survey of ICES Division IIIa, IVa, IVb and VIa

Summary: Six surveys were carried out during late June and july covering most of the continental shelf north of 54°N in the North Sea and lreland to the west of Scotland to a northern limit of 62°N. The eastern edge of the survey area is bounded by the Norwegian and Danish coasts, and to the west by the Shelf edge between 200 and 400 m depth. The surveys are reported individually, and a combined report has been prepared from the data from all surveys. The combined survey results provide spatial distributions of herring abundance by number and biomass at age by stat rectangle