Size-specific spatiotemporal dynamics of bigeye tuna (Thunnus obesus) caught by the longline fishery in the eastern Pacific Ocean
Size-specific spatiotemporal dynamics of bigeye tuna (Thunnus obesus) caught by the longline fishery in the eastern Pacific Ocean
复制标题
东太平洋延绳钓捕捞大眼金枪鱼（Thunnus obesus）尺寸特定时空动态
DOI：
10.1016/j.fishres.2021.106065
复制
发表时间：
2021
影响因子：
2.4
通讯作者：
M.N. Maunder and T. Kitakado
中科院分区：
文献类型：
--
作者：
Satoh;K.;H. Xu;C.V. Minte-Vera;M.N. Maunder and T. Kitakado
本研究旨在了解 1991 年至 2017 年东太平洋大眼金枪鱼 (Thunnus obesus) 特定尺寸的时空动态。采用时空三角洲广义线性混合模型来收集从日本延绳钓渔业收集的按尺寸等级的捕获率数据。结果表明，东太平洋大眼金枪鱼的密度在空间上存在差异，并根据大小存在空间隔离。研究区域（100–150°W，10°S–10°N）按尺寸预测的平均密度表明，成鱼（叉长（FL）> 152°cm）主要分布在该研究区域中部，西经110–140°C。中等尺寸阶段（FL> 115至< = 152 cm），西部和东部均出现高密度区，但主要集中在北半球和西经120°以东。研究区西南部发现了幼虫期高密度区（FL < = 115 cm）。还观察到了针对厄尔尼诺和拉尼娜现象的规模空间重组。厄尔尼诺和拉尼娜现象导致成鱼分别分布在东部和西部EPO，较小的鱼类分布在相反的区域。海洋条件对不同大小的鱼类分布和运动的影响不同，不同大小的相对丰度趋势也不同。我们讨论了按大小分类的原因以及每种鱼类大小类别对海洋条件的不同反应。
This study aimed to understand the size-specific spatiotemporal dynamics of bigeye tuna (Thunnus obesus) in the eastern Pacific Ocean from 1991 to 2017. A spatiotemporal delta-generalized linear mixed model was applied to catch rate data by size class collected from a Japanese longline fishery. The results showed that the density of bigeye tuna varied spatially across the eastern Pacific Ocean, with spatial segregation by size. The mean predicted density by size in the study area (100–150 °W, 10 °S–10 °N) indicated that adult fish (fork length (FL) > 152 cm) were mainly distributed in the middle of this study area, 110–140 °W in both hemispheres. For the intermediate size stage (FL > 115 to < = 152 cm), a high-density area was found in both the western and eastern parts, but mainly in the northern hemisphere and east of 120 °W. A high-density area of the juvenile stage (FL < = 115 cm) was found in the southwestern part of the study area. Spatial restructuring by size in response to El Niño and La Niña was also observed. El Niño and La Niña caused adult fish to distribute in the eastern and western EPO, respectively, and the smaller fish were distributed in the opposite area. Oceanographic conditions affect fish distribution and movement differently according to size, and the trends in relative abundance by size were different. We discuss the reasons for the segregation by size and the different responses of each fish size category to oceanographic conditions.