Mesh Selectivity of Small Trawl for White-spotted Conger in Osaka Bay.
Mesh Selectivity of Small Trawl for White-spotted Conger in Osaka Bay.
复制标题
大阪湾小拖网捕捞白斑海鳗的网状选择性。
DOI：
10.2331/suisan.60.735
复制
发表时间：
1994
影响因子：
0.4
通讯作者：
T. Tokai
中科院分区：
文献类型：
--
作者：
T. Nishikawa;M. Tanda;T. Nagahama;T. Tokai
大阪湾的小型水獭拖网渔业采用20 mm左右小网目的鳕鱼，因为它们的目标物种是白点康鱼和小型对虾，如南方粗虾Trachypenaeus curvirostris。许多幼鱼在未来的资源控制中发挥着重要作用，但由于这些幼鱼大多小于商业大小，因此在渔网拖网后立即被捕获并丢弃在海上。本文介绍了白点康鱼的网目选择性。1991年7月和10月，使用现有的有盖网的拖网进行了捕鱼试验。所使用的拖网有4种网目尺寸(21.2、22.5、25.0和27.0 mm)的网眼，盖网的网目尺寸为15.3 mm。网目选择性表现为G/P(体围/网目周长)的函数。当G/P=1时，筛分选择性增加，在G/P约为1.25时达到100%。这表明白点康鱼可以穿过比自身周长略小的网眼。
The small otter trawl fisheries in Osaka Bay use cod-end of small mesh size of about 20mm in stretch measure, since their target species are white-spotted conger Conger myriaster and small shrimps e. g. the southern rough Shrimp Trachypenaeus curvirostris. Many juveniles, which play an important role for future resource control, are caught and discarded at sea immediately after net hauling because most of these juveniles are smaller than the commercial size. This paper describes the mesh selectivity for white-spotted conger. Fishing experiments were carried out using an existing trawl with cover net in July and October 1991. The trawl used had a cod-end of four mesh sizes (21.2, 22.5, 25.0, and 27.0mm) and the mesh size of the cover net was 15.3mm. Mesh selectivity for white-spotted conger is shown as a function of G/P (body girth/mesh perimeter). Mesh selectivity increases at G/P=1, reaching 100% at a G/P of about 1.25. This indicates that white-spotted conger can pass through a mesh of slightly smaller perimeter than their own body girth.