Application of pop-up satellite archival tag technology to estimate postrelease survival of white marlin (Tetrapturus albidus) caught on circle and straight-shank (“J”) hooks in the western North Atlantic recreational fishery*

Atlantic white marlin (Tetrapturus albidus Poey, 1860) are targeted by a directed recreational fishery and occur as incidental bycatch in commercial fisheries throughout the warm pelagic waters of the Atlantic Ocean. Total reported recreational and commercial landings of white marlin peaked at 4911 metric tons (t) in the mid-1960s, declined steadily during the next 15 years, and have since fluctuated without trend between 1000 and 2000 t despite substantial increases in fishing effort (ICCAT, 2003). Recent population assessments conducted by the Standing Committee for Research and Statistics (SCRS) of the International Commission for the Conservation of Atlantic Tunas (ICCAT) indicate that the Atlantic-wide white marlin stock is currently at historically low levels and has been severely overexploited for over three decades (ICCAT, 2003). In the 2002 white marlin assessment, the 2001 biomass was estimated to be less than 12% of that required for maximum sustainable yield (MSY) under the continuity case (ICCAT, 2003). Current harvest is estimated to be more than eight times the replacement yield (ICCAT, 2003). In response to the overfished status of white marlin, ICCAT has adopted binding international recommendations to decrease overall Atlantic landings of this species by 67% from 1996 or 1999 levels (whichever is greater) through the release of all live white marlin from commercial pelagic longline and purse-seine gears (ICCAT, 2001). HowApplication of pop-up satellite archival tag technology to estimate postrelease survival of white marlin (Tetrapturus albidus) caught on circle and straight-shank (“J”) hooks in the western North Atlantic recreational fishery*