金枪鱼延绳钓渔业中缓解海龟误捕方法研究进展

A review on the mitigation measures of the incidental sea turtles catch in tuna pelagic longline fisheries

海龟是金枪鱼延绳钓误捕的主要物种之一,如何减少其误捕是国际社会关切的热点。海龟栖息水层和环境不同于金枪鱼,钓钩和饵料等也影响海龟的误捕。文章从钓钩深度、钓钩的选择性、饵料的选择性、环境因子以及声学因素等方面综述了国内外金枪鱼延绳钓渔业中缓解海龟误捕方法的研究进展。控制延绳钓钓钩深度是缓解海龟误捕的有效途径;较大尺寸的圆型钩可以有效缓解海龟误捕;蓝色染色饵料或许能缓解海龟误捕;避开海龟偏好的海表面温度进行作业对缓解海龟误捕有效;应用声学干扰可缓解海龟误捕。建议金枪鱼延绳钓渔业中缓解海龟误捕研究应做到:确定钓钩最佳沉降深度;探索减少海龟误捕和保证金枪鱼渔获率的钓钩最佳尺寸和钩型;研究染色饵料或拟饵等对海龟选择性的影响;考虑诱饵、钓钩类型、钓钩尺寸和钓具浸泡时长对海龟误捕和海龟释放后存活率的潜在协同效应;继续开展利用声学区分海龟和金枪鱼及缓解海龟误捕方法的研究。

Sea turtle is one of the main incidental catch species in tuna pelagic longline fishing.How to mitigate the incidental catch of sea turtles is a hot topic of international concern.The habitat of sea turtle is different from that of tunas in terms of water layers and environment,and the selectivity of hook and bait also affects the incidental catch of sea turtles.In this paper,we review the studies on the mitigation measures of incidental sea turtle catch in tuna pelagic longline fishing from the aspects of hook depth,hook selectivity,bait selectivity,environmental factors and acoustic factors.The results show that:controlling the depth of the longline hook is an effective measure to mitigate the incidental catch of sea turtles;larger circle hooks can effectively mitigate the incidental catch of sea turtles;blue dyed bait might be helpful to mitigate the incidental catch of sea turtles;it is effective to avoid the preferred sea surface temperature of sea turtles while fishing;and acoustic technology can be used to mitigate the incidental catch of sea turtles.It is suggested that in future,studies on the mitigation measures of sea turtle incidental catches in tuna pelagic longline fishing should:determine the optimal hook depth;explore the optimal size and hook type to mitigate the incidental catch of sea turtles and ensure the high catch rate of tuna;study the effects of dyed bait or artificial bait on sea turtles’selectivity;consider the potential synergistic effect of bait,hook type and size,fishing gear soaking duration on the incidental catch rate,mortality rate and post release survival rate of sea turtles;and continue to carry out studies on using acoustics to distinguish sea turtles from tuna and to mitigate the incidental catch of sea turtles.