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一、刺网网目尺寸与鱼体尺度的关系(一)刺网的选择曲线:刺网网目能剌挂鱼类,这是由于鱼碰到刺网时,往往会力图穿过网目,太多数鱼体具有纺锤形和可压缩性,当鱼向前冲游时,刺网网目会沿鱼体表面滑动并紧缩鱼体,直到它无法再前进时,就被刺挂在网上;另一种情况是鱼类未察觉网片(在夜间或光照度低),鱼体的游动惯性使之刺挂网目。鱼体刺挂网目的部位,一般是鳃盖后缘至第一背鳍前缘之间;对于体长过小的鱼,其最大体周小于或等于网目周长,能够穿过网
First, the net gilli mesh size and the relationship between the size of the fish (a) Gillnet choice curve: Gill nets can assassinate hanging fish, which is because the fish hit the gill nets, often trying to cross the net, Too many fish bodies are spindle-shaped and compressible. When the fish swims forward, the gill netting slides along the surface of the fish and tightens the fish until it can no longer advance. One situation is that the fish are unaware of the mesh (at night or at low light levels) and the fish’s inertia of movement spikes the web. Fish body spines hang the net part of the site, usually the gill cover the trailing edge to the first dorsal margin between the first; for the body length is too small fish, the largest body circumference less than or equal to the perimeter of the net, able to cross the net