摘要
捕虾拖网渔业的特点是渔获组成多样性和渔获抛弃率高。在我国南海捕虾拖网渔业中,尚没有关于改善渔具种类选择性的研究。试验采用蝴蝶拖网作为试验网具,在网囊前部安装不同网目尺寸(130和110mm)和网目形状(方形和菱形)的分隔网片,将网囊分为2层即上层的虾袋和下层的鱼袋,并估算了分隔网片对主要虾类渔获的分隔率;除此以外,还通过安装TED来改善分隔网片的分隔效果。试验结果显示,虾袋中虾类渔获个体较鱼袋中的大,对比不同分隔网片设计的分隔率发现,网目尺寸对分隔效率具有显著的影响,而不同网目形状的分隔率没有显著差异;安装TED可以有效改善分隔网片的分隔效果。
Shrimp trawls are characterized by various catch species and high discard ratio. There is little known about, the species selectivity of shrimp trawl in the South China Sea. In order to improve the current status of the fisheries and protect the juvenile shrimp and fish resource, shrimp/fish separation experiments were conducted in Dapeng Gulf. Separator panels with different mesh size （ 130 and 110 mm） and mesh shape （diamond and square） were inserted into the foreside of the codends of shrimp trawl, which is named locally after butterfly trawl. Thus, the codend was divided into two levels ： shrimp bag above and fish bag below. The separator ratios of shrimp were estimated. Additional, rigid TED was installed in the extension to improve the separator efficiency. It demonstrated that the shrimp individuals retained by the shrimp bag were larger than those retained by the fish bag. Comprison of separator ratio estimated with different separator panels, it＇s more for mesh size than for mesh shape, taking significant effect on the separator ratio. Therefore, separator ratios would increase with the installation of TED.
出处
《南方水产》
2007年第1期14-19,共6页
South China Fisheries Science
关键词
虾拖网
分隔网片
种类选择性
TED
shrimp trawl
separator panel
species selectivity
TED
