Based on historical fishing patterns and local stock development, 5 areas – each consisting of two or three sub-areas – are defined in Norwegian waters of the North Sea. The management plan aims to rebuild the five spawning stocks and thereby enhance the total recruitment and catch potential. If acoustic surveys and fishery data show that the spawning stock is large and widely distributed within an area, one of the adjacent subareas is opened. Prior to the fishing season a preliminary TAC is given, and within the open subareas the fleet can operate freely. The acoustic surveys carried out in the current year will be used to validate previous biomass estimates and to estimate the recruitment strength of the 1-year old sandeels. Based on this up-dated survey information, the quota within the current year can be increased and new areas (subareas) opened.
Recruitment and spawning stock biomass
The recruitment of lesser sandeel were poor for the 2010, 2011 and 2012 year classes, but the 2013 year class was high and the 2014 medium high. The spawning stock biomass in areas 1-3 is medium high, while in area 4 it is low. The dredge survey in December 2015 indicates a low recruitment of the 2015 year class in areas 1-4. No dredge survey has been carried out in area 5 (the Viking bank), but the acoustical surveys conducted the last years show very low quantities of sandeel in this area.