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1990～1991年,在挪威北部沿海的不同拖网船上对安装在拖网后段的刚性分离栅进行了选择性试验。本文叙述和讨论了与其他方法和观察的逃鱼行动有关的大西洋鳕和黑线鳕的选择性数据。本试验使用的不锈铜分离栅的栅条间距为55mm,面积为3.2m~2,取代网囊头上网片的一部分。为了测定这一系统所获得的个体大小选择性,用一目大48mm 的内网衬在拖网网囊中,把逃过分离栅的鱼收集进一个置于分离栅上面的罩同内(目大48mm),获得大西洋鳕和黑线鳕的选择跨度为4.6～8.5cm,50%保留长度为47.8～50.2cm,使用安装在曳式运载器上的摄影机观察了鱼类在拖网内和在逃逸过程中的行动。在试验中还使用扫描声纳来监测渔具的几何形状。
In 1990-1991 selective tests were carried out on rigid traps installed in the trailing section of the trawl on different trawlers off the northern coast of Norway. This article describes and discusses selective data on codfish and haddock associated with other methods and observed escapes. The stainless steel separation grid used in this experiment has a grid spacing of 55 mm and an area of 3.2 m ~ 2, replacing part of the mesh of the mesh head. In order to determine the individual size selectivity obtained for this system, a 48 mesh wide web was lined in a trawl mesh bag and the fish escaping the separation grid were collected in a hood placed on top of the separation grid (mesh 48 mm ), The choice of cod and haddock ranged from 4.6 to 8.5 cm, and the 50% retention length was 47.8 to 50.2 cm. Fish were observed within the trawl and during escape using a camera mounted on a tractor Action. Scanning sonar was also used in the test to monitor the gear geometry.