摘要
2015年3-4月及2017年1月在南海外海进行了两次罩网渔船兼作金枪鱼延绳钓的捕捞试验,基于试验数据分析延绳钓钓钩深度及渔获水层分布,以期优化改进试验钓具,有效提高南海金枪鱼延绳钓捕捞效益。研究发现:1)经济渔获以剑鱼(Xiphias gladius)与黄鳍金枪鱼(Thunnus albacares)为主,剑鱼的单位捕捞努力量渔获量(CPUE,kg·千钩-1)为所有渔获中最高; 2)钓钩深度(D)与钩位(n)、风速(SW)、风流合压角(γ)成正相关,与漂移速度(SD)、投绳船速(SV)呈负相关,回归方程为:D=10. 259n-37. 247SD-29. 878SV+6. 940SW+23. 493γ+35. 633; 3)模型的预测结果与实测数据间无显著性差异,相对权重表明各影响因子中钩位具有最大的相对重要性; 4)试验中拟合钩深分布范围为35. 08～110. 80 m,剑鱼上钩率与CPUE最高的水层为60～80 m,黄鳍金枪鱼上钩率与CPUE最高的水层为80～100 m; 5) 60～80 m水层主要经济渔获CPUE最大且钓钩数目最多,认为钓钩水层分布较合理。
The research group used falling-net fishing vessel to conduct two tuna longline fishing experiments in the open waters of the South China Sea in April2015and January2017.We analyzed the hook depth and water level distribution of capture based on experimental data for providing reference for the optimization and improvement of experimental longline gear and effectively improving the fishing efficiency of tuna longline in the South China Sea.The study showed that:(1)The economic capture was dominated by swordfish(Xiphias gladius)and yellowfin tuna(Thunnus albacares),accounting for61.87%of the total catch weight,the catch per unit effort[CPUE,kg·(1000hooks)^-1]of the swordfish was the highest among all captures,and the value was166.92kg·(1000hooks)^-1,CPUE of yellowfin tuna was the second,23.89kg·(1000hooks)^-1;(2)We studied the the relationship between hook depth(D)and various influencing factors by using multiple linear regression model,and the results showed that the hook depth(D)was positively correlated with hook position code(n),wind speed(S W)and attack angle(γ),negatively correlated with drift speed(S D)and vessel speed(S V)when deploying longline,the regression equation was D=10.259n-37.247S D-29.878S V+6.940S W+0.410γ+35.633;(3)The data of measured hook depth(W=0.956,P=0.2779)and the data of predicted hook depth(W=0.978,P=0.7931)were both found to be in a normal distribution,in this case,a paired T test was used to test the two sets of data,and the results showed that there was no significant difference between the two sets of data(P=0.9972),the relative weight showed that hook position had the most important relative materiality among all influence factors;(4)The predicted hook depth distribution ranged from35.08to110.80m in the experiment,the water level where catch rate and CPUE of swordfish were the highest was60~80m,and the water level where catch rate and CPUE of yellowfin tuna were the highest was80~100m;(5)The water level of60~80m had the highest CPUE of predominant economic capture and the maximum number of hooks(there were2547hooks in this water level,accounting for42.05%of the total),so we believed that the depth distribution of the hooks was suitable.
作者
李杰
晏磊
杨炳忠
张鹏
LI Jie;YAN Lei;YANG Bing-zhong;ZHANG Peng(Key Lab. of Open-Sea Fishery Development, Ministry of Agriculture; Key Lab. of South China Sea Fishery ResourcesExploitation & Utilization, Ministry of Agriculture; South China Sea Fisheries Research Institute, Chinese AcademyFishery Sciences, Guangzhou 510300, China)
出处
《海洋渔业》
CSCD
北大核心
2018年第6期660-669,共10页
Marine Fisheries
基金
国家科技支撑计划课题(2013BAD13B06)
农业部财政重大专项(NFZX2013)
中央级公益性科研院所基本科研业务费专项(2015TS14)
关键词
罩网
金枪鱼延绳钓
钩深
多元回归分析
渔获水层
falling-net
tuna longline
hook depth
multivariate regression analysis
capture depth
