Catch Control in the Blue Whiting Pelagic Trawl Fishery - Research Cruise Report [2022825]: FV “Vikingbank”

Abstract

This cruise has demonstrated that the catch limitation system can successfully limit catches in the blue whiting pelagic trawl fishery, with negligible loss during the fishing operation while effectively releasing excessive fish when the codend is full (sections 3 & 6),. This solution can significantly reduce the risk of burst codends and discarding of excess fish, thereby making the blue whiting fishery more sustainable and potentially more profitable, through appropriate certification. However, further work is needed on an effective fish lock design (section 4) and a bycatch release system that does not release excessive target catch (section 6). The depth triggered releasers for reliable release of the codend choker also require further development and testing, which should include defining the optimal release depth (sections 5 & 9). In addition to catch limitation, this cruise also investigated the potential risk to the safety of the vessel and crew, during haul-back and pumping, by estimating the weight in water of the catch with total loss of swimbladder gas buoyancy (section 10). Also tested was a prototype method to mitigate this risk during pumping, by automating the release of the pump by a depth triggered releaser (section 7).

Catch Control in the Blue Whiting Pelagic Trawl Fishery - Research Cruise Report [2022825]: FV “Vikingbank”