Design and operation methods of a mid-water trawl for quantitative sampling of a surface pelagic fish, Pacific saury (Cololabis saira)
Design and operation methods of a mid-water trawl for quantitative sampling of a surface pelagic fish, Pacific saury (Cololabis saira)
复制标题
用于表层中上层鱼类太平洋秋刀鱼（Cololabis saira）定量采样的中层拖网的设计和操作方法
DOI：
10.1016/s0165-7836(03)00178-4
复制
发表时间：
2004
影响因子：
2.4
通讯作者：
T. Kumazawa
中科院分区：
文献类型：
--
作者：
Y. Ueno;S. Suyama;Y. Kurita;T. Kumazawa
为了建立一种估算秋刀鱼资源丰度的中层拖网定量取样方法，采用两种中层拖网（SM拖网：4个网，拖网船397 GRT和KM拖网：6个网，拖网船2630 GRT）进行了试验性捕捞调查。为了确认调查区秋刀鱼的出现，我们同时进行了M-流网（流网与多个网眼大小的面板），这一直是秋刀鱼种群评估研究的传统采样工具的实验捕鱼。试验结果表明，当拖缆长度缩短至200 m时，SM拖网对秋刀鱼的采样效果较好。KM拖网对秋刀鱼的定量取样效果不佳。通过对KM拖网和SM拖网结构的比较，指出秋刀鱼中层拖网设计的基本条件是：（1）整个头绳（包括两个翼梢）浮在水面上;（2）拖网口部上板宽度应远大于拖网的最大宽度。当拖网渔船的最大宽度为9 m时，需要30 m左右。因此，SM拖网适合于秋刀鱼的定量采样。此外，我们还提出了一些建议，以准确地确定SM拖网的渔获量估计秋刀鱼资源丰度。
To establish a quantitative sampling method using mid-water trawls for estimating the stock abundance of Pacific saury (Cololabis saira), we carried out experimental fishing surveys using two types of mid-water trawl (SM-trawl: 4 panels, trawler 397 GRT and KM-trawl: 6 panels, trawler 2630 GRT). To confirm the occurrence of saury in the survey areas, we simultaneously conducted experimental fishing of M-driftnets (driftnets with multiple mesh-sized panels), which have been the traditional sampling gear for saury stock assessment research. The results of the experimental fishing revealed that the SM-trawl was effective for sampling saury when the length of the towing cable was shortened to 200m. The KM-trawl was not effective in quantitatively sampling saury. Comparisons of the structure between the KM-trawl and the SM-trawl showed that the essential conditions on the design of the mid-water trawl for sampling saury are the following: (1) the whole head rope including both the wing tips should be floated up to the surface, (2) the width of the upper panel of the trawl at the mouth should be much longer than the maximum width of the trawler. It is required about 30m, when the maximum width of the trawler is 9m. The conclusion is that the SM-trawl is suitable for sampling saury quantitatively. Moreover, we made some suggestions for precisely determining the catch rate of the SM-trawl for estimating saury stock abundance.