应用JABBA和JABBA-Select模型评估印度洋剑鱼资源

剑鱼（Xiphias gladius）是具有较高经济价值的大型旗鱼类鱼种，处于食物链的上端，对其资源评估并制定管理策略，在资源的可持续利用和生态系统保护上具有重要意义。本研究基于贝叶斯剩余产量模型(just another bayesian biomass assessment, JABBA)和它的拓展版JABBA-Select对印度洋剑鱼资源状况进行评估，分析资源丰度指数（标准化CPUE）、捕捞选择性对评估结果的影响。结果表明：JABBA-Select模型因考虑捕捞选择性和生活史信息，对资源状态的评估表现要优于JABBA模型。印度洋剑鱼的最大可持续产量（Maximum Sustainable Yield, MSY）估值为3.17万 t，当前渔获量3.01万 t，资源处于健康状态的概率为98%。评估结果对种群内禀增长率参数r的先验分布敏感性较小，参数r与环境容纳量参数K的后验分布存在负相关。所建模型不存在明显的回顾性误差，模型较稳健。预测分析显示，当总可捕量控制在3.60万t以下时，在2028年前不会处于资源型过度捕捞（overfished）和捕捞型过度捕捞(overfishing)。

Stock assessment for Indian Ocean swordfish (Xiphias gladius) with JABBA and JABBA-Select models

Swordfish (Xiphias gladius) is a large swordfish species with high economic value and is at the upper end of the food chain. It is important to assess its resources and develop management strategies for sustainable resource use and ecosystem conservation. In this study, we assessed the resource status of Indian Ocean swordfish based on the JABBA (Bayesian biomass assessment) and its extended version JABBA-Select, and compared and analyzed the effects of CPUE data and fishing selectivity on the assessment results. The results showed that when the data can satisfy the JABBA-Select model, the JABBA-Select model performs better than the JABBA model in stock assessment because it considers fishing selectivity and life history information. The Maximum Sustainable Yield (MSY) of the Indian Ocean swordfish resource in 2018 was estimated 31,700 t, which is higher than the current catch of 30,100 t, with a 98% probability of being in a healthy state. The assessment results were less sensitive to the prior distribution of parameter r, and there was a negative correlation between the posterior distribution of parameter r and K. There was no significant retrospective problem in the proposed model. The projection analysis shows that the resource remains in neither overfished nor overfishing until 2028 when the TAC is below 36,000 t.