Dredge Bag Design Modifications As a Tool to Reduce Flatfish Bycatch in the Atlantic Sea Scallop Fishery

The Georges Bank sea scallop (Placopecten magellanicus) fishery is currently the most valuable single species fishery in the United States.  Bycatch, however, represents a considerable challenge for industry and managers, both of which are driven by market demands for sustainability and increasing accountability for a wide range of bycatch species.  Gear modifications, as one component of an overall bycatch mitigation strategy, represent an effective tool for reducing the incidental capture of some species.  Prior experimental observations suggest that flatfish bycatch is, in part, a function of apron length and twine top hanging ratio.  We hypothesized that by reducing apron length and twine top hanging ratio, the relative position of the sweep chain facilitates increased flatfish contact in an area of the dredge conducive to escapement.   To test this hypothesis, an experimental dredge (5 ring apron, 1.5:1 twine top hanging ratio) was fished relative to a dredge configuration typical of industry practices (8 ring apron, 2:1 twine top hanging ratio) .  Results indicate that the experimental gear reduced flatfish bycatch (33.18 - 44.91%) with minimal loss in scallop catch (6.45%).  This study demonstrates how simple gear modifications can reduce bycatch rates and function as a component of a comprehensive mitigation strategy.