基于连续型时滞差分模型的南大西洋长鳍金枪鱼资源评估  

Stock Assessment of Southern Atlantic Albacore Fishery Based on the Continuous Time Delay-difference Model

作　　者：张魁[1] 许友伟[1] 廖宝超[2] ZHANG Kui;XU Youwei;LIAO Baochao(Key Laboratory of Open-Sea Fishery Development,Ministry of Agriculture and Rural Affairs,South China Sea Fisheries Institute,Chinese Academy of Fishery Sciences,Guangzhou 510300,China;Department of Mathematics,Shandong University,Shandong 264209,China)

机构地区：[1]中国水产科学研究院南海水产研究所,农业农村部外海渔业开发重点实验室,广东广州510300 [2]山东大学数学与统计学院,山东威海264209

出　　处：《海洋湖沼通报》2020年第1期115-123,共9页Transactions of Oceanology and Limnology

基　　金：国家重点研发计划专项(2017YFE0104400);国家实验室"青岛海洋科技"开放性项目(2016LMFSB14);山东省自然科学基金(ZR201702060096)资助。

摘　　要：南大西洋长鳍金枪鱼群体是全球资源状况维持较好的金枪鱼群体之一,剩余产量模型(Surplus production model,SPM)、年龄结构模型(Age-structured population model,ASPM)和贝叶斯产量模型(Bayesian surplus production model,BSPM)等都已成功运用于该群体的资源评估。连续型时滞差分模型(Continuous delay-difference model,CTD-DM)是在时滞差分模型(Delay-difference model,D-DM)基础上考虑了生物过程充分时间延迟构建起来的模型,比起ASPM需要较少的数据,并且比SPM更具有生物学意义。本文在离散型D-DM基础上构建了CTD-DM,并应用在南大西洋长鳍金枪鱼渔业数据中。结果显示,CTD-DM评估的最大可持续产量(Maximum Sustainable Yield,MSY)80%置信区间为21510-23118 t(中值22398 t),较ASPM和SPM等MSY评估结果偏保守。相对生物量B2011/BMSY和相对捕捞死亡系数F2011/FMSY分别为1.45和1.04,当前该群体相对资源量水平较好,但是相对捕捞死亡系数较高;BSPM和CTD-DM的风险评估结果显示,当捕捞死亡率均等于0.2时在2025年取得最大持续产量,考虑到当前渔业持保守态度和预防性策略的理念,建议捕捞死亡率应控制在0.15以内。Albacore(Thunnus alalunga)is a temperate tuna species,which is widely distributed in marine waters.In the Atlantic Ocean,the International Commission for the Conservation of Atlantic Tunas(ICCAT)has divided albacore stock into three groups:the northern and southern Atlantic stocks(separated at 5°N)and the Mediterranean stock.The South Atlantic albacore stock is one of the well managed tuna stocks in the world,and has been assessed using age structure population model(ASPM),Bayesian surplus production model(BSPM)and surplus production model(SPM).In fully age-structured models,detailed biological information should be obtained,and uncertainties may create doubtful results of stock assessment.Surplus-production models only provide an overview because of the lack of biological realism.Continuous time delay-difference model(CTD-DM)was established on the basis of delay-difference model(DDM)which considers sufficient time delay of biological process.The CTD-DM is better to treat recruitment,growth and mortality rate as all varying continuously over time.The method filled gaps in the surplus production models and age structure models on stock assessment and diversified the diversity of assessment model.This study applied CTD-DM on the south Atlantic albacore fishery data.The results showed that estimated 80%confidence intervals for maximum sustainable yield(MSY)were 21756-23408 t(median 22398 t),which were conservative compared with estimated MSYs by SPM and ASPM.The estimated relative biomass B2011/BMSY and relative fishing mortality coefficient F2011/FMSY were 1.18 and 1.42,respectively.At present,the relative biomass level is in good condition but the relative fishing level is high.Results of risk assessment showed that the catch will reach the maximum sustainable yield in 2025 when catch rates were equal to 0.2 for both SPM and CTD-DM.Considering the current concept of conservative attitudes and preventive strategies in fisheries,it is recommended that fishing mortality should be controlled below 0.15.

关 键 词：连续型时滞差分模型 最大可持续产量 长鳍金枪鱼 风险评估 

分 类 号：S937.3[农业科学—渔业资源]