Assessing the Impact of U.S. West Coast Groundfish Fishery and Management on Elasmobranchs

Effective management of multispecies fisheries in large marine ecosystems is challenging. To deal with these challenges, fisheries managers are moving toward ecosystem-based management (e.g., EBFM).  Despite this shift, many marine species remain outside formal protective legislation or fishing management plans.  How do species that fall outside of formal management structures respond to changes in fisheries management strategies?  We used elasmobranch bycatch (sharks, skates, rays) collected by fisheries observers in U.S. Pacific coast groundfish fisheries from the period 2002-2013 to answer this question.  Elasmobranchs are often outside of formal protective management making them vulnerable to fishing mortality.  We grouped elasmobranchs into 15 ecomorphotypes to examine trends in relative catch within groundfish fishing sectors during the period 2002-13.  We find that large relative catch of specific ecomorphotypes are associated with specific fishing behaviors and sectors.  From largest relative catch to smallest, fleets ranked as follows: bottom trawl gear nearshore, off-shore hook and line and bottom trawl fisheries, pot fisheries, nearshore fixed gear fisheries, shrimp trawl, and pelagic trawl fisheries.  We review the impact of changes in groundfish fishing and management strategies on elasmobranchs to help identify gaps in monitoring and assessing the impact of management and policy on elasmobranch populations.