基于声学映像的南海灯光罩网渔业中鲣的时空分布  

Distribution of skipjack tuna (Katsuwonus pelamis) associated with alight falling-net in the South China Sea

作　　者：王腾 张鹏[1] 李杰[1] 张俊[1] 谢斌 晏磊[1] 杨炳忠[1] WANG Teng;ZHANG Peng;LI Jie;ZHANG Jun;XIE Bin;YAN Lei;YANG Bingzhong(South China Sea Fisheries Research Institute,Chinese Academy of Fishery Sciences,Key Laboratory of South China Sea Fishery Resources Exploitation and Utilization,Ministry of Agriculture and Rural Affairs,Guangzhou 510300,China;Key Laboratory of the Ministry of Education for Coastal and Wetland Ecosystems,College of the Environment and Ecology,Xiamen University,Xiamen 361102,China)

机构地区：[1]中国水产科学研究院南海水产研究所,农业农村部南海渔业资源开发利用重点实验室,广东广州510300 [2]厦门大学环境与生态学院,滨海湿地生态系统教育部重点实验室,福建厦门361102

出　　处：《中国水产科学》2021年第1期79-89,共11页Journal of Fishery Sciences of China

基　　金：农业农村部财政专项(NFZX2018);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(2018YB01).

摘　　要：基于灯光罩网和EY60科学探鱼仪采集鲣(Katsuwonus pelamis)的生物学数据与声学映像,通过分析后向体积散射强度SV(dB)、平均目标强度TS(dB)及单位采样体积的平均鱼类数目(NV)等信息,研究鲣的时空分布与现场目标强度变化。S13站位的鲣平均叉长(362.20±35.73)mm,S14站位的鲣平均叉长(357.66±36.61)mm,A12站位的鲣平均叉长(366.70±36.43)mm。10~50 m深度范围内,3个站位不同时段的平均SV变化模式相似。渔船开灯前(18:00~19:00),鲣主要分布于40~50 m水深;灯光打开后,鲣逐渐被诱集上浮(SV分布曲线峰值对应的深度变浅);随着灯诱时间的增长(20:00~21:00),鲣稳定分布于10~30 m深度范围内。10~50 m深度范围内,3个站位不同时段的鲣单体信号数目与平均深度变化模式相似。渔船开灯前(18:00~19:00),鲣单体信号主要分布于35 m以深;且被检测到的信号数目较少。灯光打开后,鲣逐渐被诱集上浮,表现为鲣单体信号平均深度变浅,信号数目明显增多。本研究3个站位均不存在NV极限值,所有单元均可用于鲣TS的现场计算。S13站位的鲣现场平均TS为(-51.84±3.84)dB;S14站位的鲣现场平均TS为(-49.87±3.72)dB;A12站位的鲣现场平均TS为(-49.68±2.96)dB。3个站位的鲣现场TS均呈非正态分布(P<0.05)。研究结果有助于更好地了解灯光诱集条件下的鲣行为及其声学特性,还可为鲣声学评估奠定技术基础。We investigated the distribution and the in-situ target strength(TS,dB)of the skipjack tuna Katsuwonus pelamis associated with light falling-nets in the South China Sea using the Simrad EY60 scientific echosounder.The volume backscattering strength(Sv,dB),TS,and mean number of fish per sampled volume(NV)were studied.The average fork length of skipjack tuna in the S13,S14,and A12 stations were(362.20±35.73)mm,(357.66±36.61)mm,and(366.70±36.43)mm,respectively.There was no significant difference in the average fork length among the three stations(P>0.05).Within the depth range of 10-50 m,the mean SV change pattern of the three stations at different time phases was similar.Before the fishing lights were turned on(18:00-19:00),the K.pelamis was mainly distributed at a water depth of 40-50 m;after the lights turned on,the K.pelamis was gradually attracted and floated,and thus the depth corresponding to the peak of the SV distribution curve became shallower.With the increase of lighting time(20:00-21:00),the K.pelamis was stably distributed at a depth range of 10-30 m.In the depth range of 10-50 m,the number of individual signals at the three stations in different time phases was also similar to the mean depth change pattern.Before the fishing lights were turned on(18:00-19:00),the signals were mainly distributed at a depth of 35 m,and few signals were detected.After the lights were turned on,K.pelamis were gradually attracted and floated,resulting in a shallower mean depth of the signals,and the number of signals increased significantly.There were no NV limit values at the three stations in this study,and all cells can be used for the in-situ TS calculation.The mean in-situ TS was(-51.84±3.84)dB at the S13 station,(-49.87±3.72)dB at the S14 station,and(-49.68±2.96)dB at the A12 station.The in-situ TS of K.pelamis at the three stations were non-normally distributed(P<0.05).These results help us better understand the fish behavior and acoustic characteristics under the conditions of light trapping and also set up a

关 键 词：鲣 渔业声学 现场目标强度 时空分布 灯光罩网 

分 类 号：S931[农业科学—渔业资源]