Ecomare

The most difficult task with drag-net fisheries is keeping the net open. Beam trawling accomplishes this with the help of a steel pipe; otter trawlers keep their nets wide open with otter boards. With twin trawling, two cutters work together: the boats both pull the net forward and hold it open by keeping a constant distance between them. This technique is applied by cutters which fish in the North Sea for pelagic fish, such as herring, cod, whiting, coal fish, haddock and mackerel.