南海北部拖网对蓝圆鲹的选择性研究  

Size selectivity of codend mesh size of trawl for Decapterus maruadsi in northern part of South China Sea

作　　者：李亚男 杨炳忠 张鹏[2,3] 李杰 王腾[2,3] 晏磊 LI Yanan;YANG Bingzhong;ZHANG Peng;LI Jie;WANG Teng;YAN Lei(Zhongkai University of Agriculture and Engineering/College of Animal Science and Technology,Guangzhou 510230,China;Key Laboratory for Sustainable Utilization of Open-sea Fishery,Ministry of Agriculture and Rural Affairs,Guangzhou 510300,China;South China Sea Fisheries Research Institute,Chinese Academy of Fishery Sciences,Guangzhou 510300,China)

机构地区：[1]仲恺农业工程学院动物科技学院,广东广州510225 [2]农业农村部外海渔业可持续利用重点实验室,广东广州510300 [3]中国水产科学研究院南海水产研究所,广东广州510300

出　　处：《南方水产科学》2022年第3期170-176,共7页South China Fisheries Science

基　　金：中国水产科学研究院南海水产研究所中央级公益性科研院所基本科研业务费专项资金资助(2020YJ01);农业部财政重大专项(NFZX2018);农业农村部财政项目(1720018)。

摘　　要：为确定南海拖网最小网目尺寸标准的适应性,采用套网法在南海北部对网目尺寸分别为30、35、40和45 mm的菱形网目(分别以D30、D35、D40和D45表示)进行了选择性试验。使用Logistic和Richards模型分别拟合了不同网目网囊下蓝圆鲹(Decapterus maruadsi)的选择性曲线,并通过比较两种模型的偏差和自由度确定最佳拟合曲线。结果显示,Logistic曲线对D30、D35和D45网囊的拟合效果更好,而Richards曲线对D40网囊的拟合效果更好。D30、D35、D40和D45网囊对蓝圆鲹的50%选择叉长(50%retention fork length,L_(0.5))分别为12.43、12.88、13.60和16.79 cm,选择范围(Selection range,SR)分别为8.45、6.75、6.08和2.19 cm。随着网目尺寸的增大,蓝圆鲹的L_(0.5)逐渐增加,而SR逐渐减小。根据蓝圆鲹的L_(0.5)和网目大小关系式计算得出的最小网目尺寸为41.39 mm。为保护蓝圆鲹等中小型经济鱼类,建议将南海拖网菱形网囊最小网目尺寸设定为45 mm。To determine the suitability of minimum mesh size standards for trawls in the South China Sea,we conducted selectivity tests in that area by using the covered net method with mesh sizes of 30,35,40 and 45 mm(Denoted as D30,D35,D40 and D45,respectively).We used Logistic and Richards models to fit selectivity curves for Decapterus maruadsi by the maximum likelihood method,and determined the best-fitting curves by comparing the model deviations and degrees of freedom of the two models.The results show that the Logistic curve fitted better for D30,D35 and D45 mesh codend,while the Richards curve fit better for D40 mesh codend.The 50%retention fork lengths(L_(0.5))of D.maruadsi for D30,D35,D40 and D45 were 12.43,12.88,13.60 and 16.79 cm,respectively.As the mesh size increased,the L_(0.5)of D.maruadsi increased but the selection range decreased gradually.The minimum mesh size was 41.39 mm based on the relationship between L_(0.5)and mesh size of D.maruadsi.Thus,45.39 mm is suggested as the minimum mesh size for trawl in the South China Sea to protect small and medium-sized economic fish such as D.maruadsi.

关 键 词：蓝圆鲹 拖网选择性 最小网目尺寸 套网法 南海 

分 类 号：S975[农业科学—捕捞与储运]