Survival of White Marlin (Tetrapturus albidus) Released from Commercial Pelagic Longline Gear in the Western North Atlantic

To estimate post-release survival of white marlin caught incidentally to regular commercial pelagic longline fishing operations targeting swordfish and tunas, short-duration pop-up satellite archival tags (PSATs) were deployed on captured animals for periods of 5 - 43 days. Twenty of 28 (71.4%) tags transmitted at the pre-programmed time, including one tag that became detached from the fish shortly after release and was omitted from subsequent analyses. Transmitted data from 17 of 19 tags were consistent with survival of those animals for the duration of the tag deployment. Estimates of post-release survival range from 63.0% (assuming that all nonreporting tags were mortalities) to 89.5% (excluding non-reporting tags from the analysis). The results of this study indicate that white marlin can survive the trauma resulting from interaction with pelagic longline gear, and suggest that current domestic and international management measures requiring the release of live white marlin from this fishery will reduce fishing mortality on the Atlantic-wide white marlin stock.