Development and testing of a species-selective flatfish ottertrawl to reduce cod bycatches

The objective of this project was to develop a trawl suitable for directed fisheries for flatfish that would reduce cod bycatch. A selective flatfish trawl was developed and tested in a flume tank. A sea trial was conducted in the Danish plaice fishery in the Skagerrak and two sea trials were run on the Baltic sea flounder fishery. The catches from the selective flatfish trawl were compared to catches made with a conventional flatfish trawl. The selective flatfish trawl caught more plaice and reduced the cod bycatch, particularly those smaller than the minimum landing size in the Skagerrak sea trials, compared to the conventional flatfish trawl. The selective flatfish trawl caught more flounder and reduced cod bycatch during two sea trials in the Baltic sea. Hence, this selective flatfish trawl appears to be a useful management tool to substantially reduce bycatch of cod in a directed plaice or flounder fishery.