瓯江口凤鲚生长、死亡和最适开捕体长  

GROWTH,MORTAILY AND OPTIMUM CATCHABLE SIZE OF COILIA MYSTUS IN OUJIANG RIVER ESTUARY

作　　者：李霞芳 蒋日进[2] 芮银 王雅丽 孙浩奇 印瑞 李凯 胡忠健 LI Xia-Fang;JIANG Ri-Jin;RUI Yin;WANG Ya-Li;SUN Hao-Qi;YIN Rui;LI Kai;HU Zhong-Jian(Marine and Fishery Institute of Zhejiang Ocean University,Zhoushan 316021,China;Ministry of Agriculture and Rural Affairs Scientific Observation and Experimental Station of Fishery Resources of Key Fishing Grounds,Zhejiang Province Key Laboratory of Sustainable Utilization of Technology Research for Fisheries Resources,Zhejiang Marine Fisheries Research Institute,Zhoushan 316021,China;Wenzhou Fisheries Technology Extension Service Center,Wenzhou 325027,China)

机构地区：[1]浙江海洋大学海洋与渔业研究所,舟山316021 [2]浙江省海洋水产研究所,农业农村部重点渔场渔业资源科学观测实验站,浙江省海洋渔业资源可持续利用技术研究重点实验室,舟山316021 [3]温州市渔业技术推广站,温州325027

出　　处：《水生生物学报》2022年第9期1393-1401,共9页Acta Hydrobiologica Sinica

基　　金：浙江省公益性技术应用研究项目(LGN20C190012);国家重点研发计划(2020YFD0900805)资助。

摘　　要：根据2015、2018—2020年瓯江口水域渔业资源监测调查资料,对1359尾凤鲚的体长、全长和体重等生物学信息进行测定,利用体长频率分布估算凤鲚种群生长、死亡参数等。结果表明,瓯江口凤鲚体长为5.2—21.9 cm;体长和体重的关系式W=0.0035×L^(3.0783)。用ELEFAN技术拟合的von Bertalanffy生长方程的各参数为L_(∞)=26.60 cm,k=0.47及t_(0)=–0.55 a;Z=2.30,M=1.00,F=1.30,E=0.567,表明资源处于过度开发状态;凤鲚的首次捕捞体长Lc=15.35 cm,对应首次捕捞平均年龄为1.28 a,小于临界年龄(1.36 a)和体重生长的拐点年龄(1.85 a),表明当前渔业主要捕捞对象为幼鱼和补充群体,无法保证资源的有效补充。在瓯江口凤鲚目前的资源状态下,应努力降低捕捞死亡率,并加强对凤鲚栖息环境的保护,而对目前以小型化和低龄化为主的凤鲚群体,以控制开捕体长为主,根据Beverton-Holt动态模型,建议开捕体长为15.50 cm,对应开捕年龄为1.31 a。Coilia mystus is one of the main fishing species in Oujiang River Estuary and it has high economic value.Based on the fishery resources monitoring data collected in Oujiang River Estuary in Wenzhou from 2015 and 2018 to 2020,the present study analyzed the biological characteristics(n=1359)of C.mystus,including body length,total length and body weight.The population growth and death parameters were estimated by body length frequency distribution.The results indicated that the average body length of C.mystus in Oujiang River Estuary was(15.1±3.0)cm,with the group of predominant body length 14.0—18.0 cm,accounting for 54.3%;the average body weight was(16.8±10.1)g,with the group of predominant body weight 5.0—25.0 g,accounting for 72.0%.The distribution of body length and body weight differed significantly between males and females(P<0.05).The average body length and body weight of females were greater than those of males,but the body length-weight relationship was not significantly different(P>0.05).The relationship between body length and weight was expressed as:W=0.0035×L^(3.0783)(R^(2)=0.9509).The power exponent b was 3.0783,which is consistent with uniform growth characteristics.The growth parameters of von Bertalanffy formula estimated by ELEFAN were L_(∞)=26.60 cm,k=0.47,and t_(0)=−0.55 a.The total mortality coefficient(Z)was calculated using a length-converted catch curve as 2.30.The natural mortality coefficient(M)estimated referring to the Pauly empirical formula,was 1.00.Therefore,fishing mortality coefficient(F)was 1.30,and the exploitation rate(E)equaled 0.567,demonstrating that the stock had been over-exploited.The catch curve also determined that the current first capture L50 was 14.50 cm,corresponding to an age of 1.13,which was lower than both the critical age(1.36 a)and the turning point age(1.85 a).This indicated that the main fishing objectives were juveniles and included the recruitment group of C.mystus.Under the current resource status in Oujiang River Estuary,great amount of effort

关 键 词：生物学参数 最适开捕体长 瓯江口 凤鲚 

分 类 号：S932.4[农业科学—渔业资源]