A cooperative research gillnet study: The effects of hanging ratio on Harbor porpoise bycatch and targeted finfish species

In waters off the Northwest Atlantic coast of the United States, the Harbor Porpoise Take Reduction Plan has been in effect since December 1998, requiring gillnet gear to be modified during certain times of the year and in certain areas of the Gulf of Maine, southern New England and the Mid-Atlantic. The intention is to reduce harbor porpoise interactions with gillnet gear using acoustic deterrents (pingers) or gear modifications.   Industry input from New England fishermen has indicated financial difficulties associated with the use of pingers and a more cost effective method maybe using gear modifications. In 2009 we began a project funded by the National Marine Fisheries Service (NMFS) Bycatch Reduction Engineering Program designed to further investigate the effect of hanging ratio on harbor porpoise by-catch and targeted finfish species.   Working cooperatively with NMFS and two captains of commercial gillnet vessels, 79 hauls were completed in the first field season in winter 2009. Initial results indicate a difference in catch rates of commercially important finfish species and harbor porpoise by-catch based on hanging ratio. This project intends to address bycatch concerns with the gillnet industry in hopes of integrating management and industry needs.