A trawl net bag selectivity test device

Abstract

The invention discloses a trawl-net net-bag selective testing device which comprises a fishing boat, struts, a plurality of test trawl nets and a plurality of underwater cameras, the struts are laterally installed on the sides of the fishing boat; the test trawl net comprises warps, cross ropes, a net body, a test net bag and a cover net, the net openings of the net body are connected to one endsof the warps by the cross ropes, the other ends of the warps are fixed on the struts, the net opening of the test net bag is sutured with the edge of the tail outlet of the net body, the tail outlet of the test net bag is tightly closed by a first bundle rope, the cover net sleeves outside the test net bag, the edge of the opening of the cover net is sutured with the tail of the net body, the tailoutlet of the cover net is tightly closed by a second bundle rope, the plurality of test trawl nets are laterally distributed, and underwater cameras are installed at the net openings of the net body. The trawl-net net-bag selective testing device can realize the test fishing of the multiple sets of test net bags at the same time, and overcomes the problems of a cover net method and a comparativeoperation method.

Description

technical field [0001] The invention relates to the field of fishing gear, in particular to a trawl net bag selectivity testing device. Background technique [0002] Trawling is a fishing gear that is towed by a fishing boat to force the target to enter the net bag. The net bag is the bag-shaped part of the trawl net where the final catch is collected. Trawl is the most important fishing gear in my country's marine fishing industry. It spreads all over the country's coastal provinces (regions) and cities. It catches a wide range of objects, and its output ranks first among the 12 types of fishing gear. However, with the decline of fishery resources, relevant management departments have fully realized that it is necessary to formulate corresponding management systems for trawl fisheries. Among them, specifying the minimum mesh size of the trawl mesh bag is one of the most important management systems. [0003] However, the establishment of the minimum mesh size must be bas...

AI Technical Summary

Problems solved by technology

Although the comparative operation method can avoid the influence of the coverage effect, the relative operation intensity of the experimental mesh and the control mesh is not clear, and there are also problems of low comparability between meshes, heavy workload, high economic cost, and long time-consuming

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