The mechanisms most likely to determine the distribution of the two major herring Clupea harengus stocks in their common early summer feeding ground in the eastern North Sea, Skagerrak and Kattegat were investigated through analysis of acoustic survey data from six consecutive years. No change was detected in biomass of North Sea autumn spawning C. harengus ( NSAS ) over time, whereas the biomass of western Baltic spring spawn...

Data on catch per unit effort (CPUE) from the Danish commercial fishery showed dense aggregations of sprat Sprattus sprattus born in 1997 in the main spawning area of the Baltic Sea during May 1999. After the analysis of their otolith macrostructure, these fish were found to have a shorter distance to the beginning of the first winter zone compared to fish from the same cohort caught in other months. At the same time, the numb...

The three‐dimensional (3‐D) shape and density distribution of a cod otolith was determined using a newly developed micro X‐ray tomograph. The technique requires no special treatment of the otolith and could yield the entire 3‐D growth history in a single analysis. 999 The Fisheries Society of the British Isles