The collection of accurate fisheries catch data is critical to ensuring sustainable management of tuna fisheries, mitigating their environmental impacts and for managing transboundary fish stocks. These challenges are exemplified by the western Pacific tuna longline fishery, who’s management includes >26 nations, but is informed by critically low coverage of fishing activities by scientific observers. The gap in observer data could be filled by electronic monitoring (EM), but there are few trials that span multiple nations. A large-scale trial of EM systems on tuna longliners based in Palau, Federated States of Micronesia and the Republic of the Marshall Islands, is reported on. Comparisons are made of catch rates of market and bycatch species in corresponding EM, logbook and human observer data. Retained species were under-reported in logbooks by up to three times and discards of many species were not reported in logbooks. Discards identified in the EM data included threatened species such as marine turtles. Catch rate estimates from EM data were comparable to those estimated by human observers. EM data recorded a higher species diversity of catches than logbook data. Analysis of the EM data indicated clusters of bycatch that were associated with specific fishing practices. These results suggest further expansion of EM could inform improved management of both target and bycatch species. Ultimately greater coverage of EM data could contribute to reconciling debates in international stock allocation schemes and support actions to reduce the impacts of the fishery on threatened bycatch species.

收集准确的渔业捕捞数据对于确保金枪鱼渔业的可持续管理、减轻其环境影响和管理跨界鱼类种群至关重要。这些挑战以西太平洋金枪鱼延绳钓渔业为例，该渔业管理的国家超过 26 个，但科学观察员对捕捞活动的覆盖率极低。观察者数据的空白可以通过电子监测 (EM) 来填补，但很少有跨越多个国家的试验。据报道，在帕劳、密克罗尼西亚联邦和马绍尔群岛共和国对金枪鱼延绳钓渔船进行了大规模的电磁系统试验。在相应的 EM、日志和人类观察者数据中对市场和兼捕物种的捕获率进行了比较。日志中保留的物种少报了多达三倍，而且日志中没有报告许多物种的丢弃物。EM 数据中确定的丢弃物包括海龟等受威胁物种。EM 数据的捕获率估计值与人类观察者估计的捕获率估计值相当。EM 数据记录的渔获物物种多样性高于日志数据。对 EM 数据的分析表明与特定捕捞方式相关的兼捕集群。这些结果表明 EM 的进一步扩大可以为改善目标和兼捕物种的管理提供信息。最终扩大 EM 数据的覆盖面可能有助于协调国际种群分配计划中的辩论，并支持采取行动减少渔业对受威胁的兼捕物种的影响。