SU1741696A1 - Method for guiding fish into trawl catching zone - Google Patents

Abstract

Usage: in the fishing industry to direct fish to the ool zone. Summary of the invention: in the zone located between the ship and the trawl mouth, fish are affected by signals having discrete components in the frequency range of 8–18 Hz, a maximum frequency floating in the range of 1700–2800 Hz, containing the fundamental frequency and harmonics. The sound pressure level at frequencies of 1700 - 2800 Hz is 120 - 130 dB with respect to 2 x x Pa. The initial pulse of the signal has a duration of 0.006 - 0.01 s. The displacement of water particles at the location of the object of fishing is 0.42 - 10 µm. The pneumatic emitters are fixed on the fans and started from the vessel. 5 hp f-ly. 1 il.

Description

The invention relates to the fishing industry, in particular to methods and devices for directing fish to the trawl fishing zone.

The purpose of the invention is to increase the efficiency of trawling by using acoustic signals that cause the fish to skew and to move to the trawl fishing zone.

 This goal is achieved by the fact that in a known method of directing fish to the trawl harvesting zone, which involves the inclusion of acoustic emitters in the wire-line and the impact on the fish in the zone located between the vessel and the mouth of the trawl, signals of pneumatic radiators having a duration of 0.7 - 1 are used. , 5 s and the period of the following 10 - 15 s. discrete components in the frequency range of 8–18 Hz. floating maximum in the frequency range 1700 - 2800 Hz, containing the fundamental frequency and harmonics. The level of sound,

The pressure at the location of the object of fishing at frequencies of 1700–2800 Hz is 120–130 dB relative to Pa, and the initial pulse of the signal has a duration of 0.006– 0.01 s and a displacement of water particles of 0.42–10 µm in the frequency range 8–18 Hz In addition, two groups of pneumatic radiators of 3–5 pieces each, are fixed on warps with the possibility of moving a distance of 10–20 m above the upper edge of the fish cluster and launched from the vessel with the help of a cable. Two other groups of pneumo-radiators, mounted on the end part of the wafers in the zone of their maximum opening, are launched from the ship via the hydroacoustic communication channel.

The drawing shows a general scheme for the implementation of the directing of the fish to the trawl fishing zone.

The method of directing fish to the trawl catch zone 1 is carried out with the help of four groups of autonomous pneumatic radiators 2-5. Two groups of pneumatics

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The emitters (PI) 2 and 3 are mounted on the end part of the warp 6 and are placed in the process of trawling between the trawl boards 7 in the zone of maximum warp opening 6. The PI 2 and 3 groups are launched from ship 8 of the ship’s sonar channel electronic prefix. The other two groups of PI 4 and 5 are fixed on the warps 6 with the help of carbines 9 and fixed in the water column with the help of two cables 10 and 11, along which the PI 4 and 5 groups are started and the length is adjusted from the vessel 8 depending on from the position of the scoops 12-14.

When a fish 8 group of groups of PI 4 and 5 appears under the keel of the ship, they are brought to the horizon 10-20 m above the upper edge of the cluster and are put into operation by cables 10 and 11. If there is a need for prolonged exposure of the signals to the fish In the catch zone by trawl 1, the PI groups 4 and 5, as the cable cables 10 and 11 are etched, are lowered along the warps 6 together with the upper edge of the spit to the depth of the trawl 1. To affect several spit 12 and 13 or, if the cluster has large extent on the horizon and depth, the PI groups 4 and 5 They are stepped on different parts of warp 6 depending on the depth of the object.

The launch of groups PI 2 and 3 is carried out in the event that trawl 1 flows to a sparse accumulation of fish 14 whose dimensions are larger than the horizontal opening of trawl 1.

The use of the proposed method of directing fish to the catch zone by a trawl provides the following advantages over existing technical solutions:

when fish are exposed to signals of pneumatic emitters with the parameters proposed above, the effect of cross-linking (compaction) of rarefied clusters in front of the fisherman and their directional movement to the trawl fishing zone is achieved;

placing the groups of pneumatic radiators on the warps with the possibility of their movement along the entire length of the warpers between the vessel and the trawl allows for the accumulation of fish lying above the upper trawl pickup in the catch zone of the trawl;

The proposed method allows to significantly expand the trawling area and, correspondingly, increase its catchability almost without increasing energy costs, fuel and materials,

Claims (6)

1. The method of directing fish to the trawl fishing zone, which involves the inclusion of acoustic emitters in the wire line of cable ib and the impact on the fish in the area located between the vessel and the mouth of the trawl, which is characterized by the fact that ly pneumatic radiators having a duration of 0.7–1.5 s and a follow up period of 10–15 s, discrete components in the frequency range of 8–18 Hz, a maximum frequency floating in the 1700–2800 Hz range, containing the fundamental frequency and harmonics, while the sound pressure level at frequencies of 1700–2800 Hz is 120–130 dB relative to Pa, the initial pulse of the signal has a duration of 0.006– 0.01 s, and the displacement of water particles in the location of the fishing gear i is 0.42 - 10 microns. 2. A method according to claim 1, characterized in that the two groups of pneumo-radiators of 3-5 pieces are fixed on warps. 3. The method according to paragraphs. 1 and 2, characterized in that the pneumatic emitters are launched from the vessel with the help of a cable. 4. Method according to paragraphs. 1-3, characterized by the fact that air radiators fix on warps with the ability to move to a distance of 10-20 m above the upper edge of the fish aggregation. 5. Method according to paragraphs. 1 - 3, that is, so that the pneumo-radiators are moved with the help of para-planes controlled by horizon and depth. 6. Method 1 and 2, characterized in that the pneumo-emitters are launched from the ship through a hydroacoustic communication channel. I Ј YEF // AW : Uh "