| 摘要: |
| 2005 年8—12 月, 利用金枪鱼延绳钓渔船对帕劳群岛附近海域进行调查, 研究大眼金枪鱼的环境偏好。所获数据包括：①温度、盐度、溶解氧垂直分布, 测定的钓钩深度; ②作业参数; ③渔场气象数据; ④渔获统计数据。分析方法和步骤为：①应用逐步回归的方法, 建立钓钩预测深度计算模型; ②根据温度、盐度、溶解氧垂直分布曲线、预测深度、取样数据, 利用统计和聚类分析的方法分析大眼金枪鱼的环境偏好。结果表明：①在帕劳群岛附近海域, 大眼金枪鱼偏好的水层为180.0—219.9m、水温范围为11.0—12.9℃、盐度范围为34.50—34.99、溶解氧范围为3.00—3.99mg/L; ②一般情况下, 水温及其体温的变化决定成熟大眼金枪鱼的活动水层, 其偏好的水温为10.0—14.0℃; ③大眼金枪鱼的适盐性较广; ④溶解氧高于门限值(0.8mg/L)时, 大眼金枪鱼的分布由其它环境因子决定。
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| 关键词: 大眼金枪鱼, 水层, 水温, 盐度, 溶解氧, 延绳钓, 帕劳 |
| DOI：10.11693/hyhz200906015015 |
| 分类号: |
| 基金项目:上海市重点学科建设项目资助, S30702 号; 深圳市联成远洋渔业有限公司资助, 技05-26 号 |
附件 |
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| ENVIRONMENTAL PREFERENCES OF THUNNUS OBESUS NEAR PALAU: APPLICATIONS TO LONGLINE FISHERY |
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SONG Li-Ming, LI Yu-Wei, GAO Pan-Feng
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The Key Laboratory of Shanghai Education Commission for Oceanic Fishery Resources Exploitation, The Key Laboratory of Sustainable Exploitation of Oceanic Fisheries Resources, Ministry of Education, Shanghai Ocean University
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| Abstract: |
| The relationships between vertical distribution of adult bigeye tuna (Thunnus obesus) and water temperature, salinity, and dissolved oxygen and the environmental preferences of the bigeye tuna near Palau were studied in this research to increase the catch rate of bigeye tuna and reduce the bycatch of non-targeting species. Longliner CFA No.07 in super-spool and chilled seawater systems was used as the platform for sampling. Sampling in waters near Palau was conducted from Aug.14, 2005 to Dec.19, 2005. The data collected included CTD (XR-620) and TDR (2050) profiles, amount of fishing hooks, deploying position and time, course and speed, shooting speed of main line, number of hooks between successive buoys, the time interval between two hooks, beginning time and position of retrieving line, wind force and direction, the drifting speed and direction to the ground, and the hook code. The theoretical hook depth was calculated with a catenary curve hook depth equation. Relationship between theoretical hook depth and the predicting hook depth was determined by regression. All the predicting hook depth was calculated with predicting hook depth model. Additionally, vertical profiles of temperature, salinity, dissolved oxygen and depth were established for estimating the catch rate of bigeye
tuna at different hydrodynamic ranges. The result indicates that the tuna longline fishing ground near Palau, the favorable conditions are about 180 to 220m deep, 11.0 to 12.9℃ in water temperature, 34.50 to 34.99 in salinity, and dissolved oxygen at 3.00 to 3.99mg/L. In general, adult bigeye tuna prefers to temperature from 10.0 to 14.0℃ in vast salinity range and at least 0.8mg/L of dissolved oxygen.
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| Key words: Thunnus obesus, Water layer, Temperature, Salinity, Dissolved oxygen, Longline, Palau |
