Device and method for selective catching test of ground cage fishing gear

Abstract

The invention relates to a device and method for a selective catching test of a ground cage fishing gear, and belongs to the technical field of marine catching, and the device comprises an inner cage,an outer cage and shared 'trumpet-shaped' inverted structures. The outer cage sleeve outside the inner cage, and 'trumpet-shaped' inverted structures are alternately arranged on the two sides of thedevice. The device can accurately and truly reflect the situations of selective catching and escape rate and output value loss rate of ground cage fishing gears with different mesh sizes. The device is simple in structure, easy to manufacture, and convenient to operate, the test times are relatively low and the test cost is low; the caught samples in the inner cage and the samples escaping from the inner cage are both collected, the samples are small and the deviation is small, and the influence of the ground cage fishing gear on the fish population in a working fishing ground can be more truly reflected.

Description

technical field [0001] The invention belongs to the technical field of marine fishing, and specifically relates to selective fishing in the fishing process of a ground cage fishing gear. A test device and method for scientifically, accurately and reasonably determining the relationship between the mesh size of ground cage fishing gear and the permitted catch. technical background [0002] Ground cage fishing gear refers to fishing gear that uses long strings of cage-like devices for trapping operations. According to the classification principle of GB5147-2003 "Classification, Naming and Code of Fishing Gear", the ground cage fishing gear belongs to the fixed longline inverted beard cage pot fishing gear (46 dax L), commonly known as ground cages, square ground cages, and rolling ground cages. String cage. The fishing principle of ground cage fishing gear is to set up cages with anti-escape whiskers according to the unique habitat, feeding or reproductive habits of the fish...

AI Technical Summary

Problems solved by technology

This test method is a large-sample sampling test method, which has many shortcomings: first, it "assumes that the fishing objects are evenly distributed in the fishery", but in fact it is not so; second, it can only reflect the composition of the catch in the ground cage, Parallel comparison of the biological data of ground cage catches with different mesh sizes shows that the release rate of larvae (ie weight escape rate and mantissa escape rate) tends to have large deviations; third, it cannot reflect the released larval biological data Composition of the actual situation (the reason is that the escaped groups have not been collected); fourth, it is difficult to estimate the loss rate of output value; fifth, the number of ground cage fishing gear and the number of tests required for the test are large, at least N≥100, which is time-consuming, laborious and expensive Wait

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