Consequences of Subpopulation Structure on Fisheries Management: Cod (Gadus morhua) in the Kattegat and Öresund (North Sea)

This study shows how cod subpopulations may have been eradicated as a consequence of the use of imperfect models for assessing stock assessment, depleting what was formerly a productive sea. The Kattegat and resund (North Sea) were chosen as study objects due to the combination of different exploitation patterns and the possible existence of separate stock units. The scenario was further elaborated by simulating the potential harvest of fishing for different long-run levels of fishing effort as well as stock size. The study clearly indicated that new policy instruments are needed but these instruments need to be carefully fine-tuned to take into account real biological as well as social factors.