利用渔场环境因子标准化西北太平洋柔鱼CPUE的研究

Standardizing CPUE of Ommastrephes bartramii in the Northwest Pacific Ocean based on environmental factors of habitat

本文利用1998-2016年西北太平洋柔鱼渔业数据及其渔场(35°～45°N,140°～165°E)的海洋遥感环境数据,包括海表温度、海面高度异常和叶绿素浓度,采用基于渔场环境的方法标准化西北太平洋柔鱼单位捕捞努力量渔获量(catch per unit effort, CPUE)。结果表明:柔鱼高频次作业的海表温度范围为10.2～22.2℃(96.05%),海面高度异常范围为-15.9～28.2 cm(97.91%),叶绿素浓度范围为0.0～1.0 mg/m^3(96.69%)。名义CPUE和基于环境因子的标准化CPUE年际变化趋势基本一致。但由于柔鱼作业方式高度集中,有效捕捞努力量远低于名义捕捞努力量,以及考虑环境因子影响效应,名义CPUE均低于标准化CPUE。在深入理解鱿钓渔业和其生物学特性的基础上,基于渔场环境因子准化后的CPUE更具代表性,建议在以后的柔鱼资源评估与管理中使用基于渔场环境因子的标准化CPUE。

An approach is developed to standard catch per unit effort (CPUE) in the Northwest Pacific Ocean during 1998-2016 by considering environmental factors, including sea surface temperature (SST), sea surface height anomaly (SSHA), and chlorophyll a (Chl a ) concentration of Ommastrephes bartramii habitat (35°~45° N,140°~165° E). It is found that the range of SST for high frequency of fishing (97.8%) is 10.2-22.2℃; the range of SSHA for high frequency of fishing (97.3%) is -15.9-28.2 cm; the range of Chl a concentration for high frequency of fishing (95.2%) is 0.0-1.0 mg/m 3 . The nominal CPUE is consistent with the yearly environmental based-CPUE. However, the nominal CPUE is significant less than environmental based-CPUE, because the highly concentrated fishing results in the effective fishing effort less than nominal fishing effort. We suggest that the environmental based-CPUE is more representative and closer to actual abundance indices of Ommastrephes bartramii , and we should consider environmental based-CPUE in the stock assessment and management for Ommastrephes bartramii in the Northwest Pacific Ocean in the future.