Method for determination of trawl catch efficiency. RU patent 2346432.

FIELD: agriculture.

SUBSTANCE: method implies use of hydroacoustic echo-ranging device to determine amount of fish in front of trawl. Hydroacoustic echo-ranging device may be installed at one and/or both trawl boards. Echo ranging of target stocks in the space between trawl boards and trawl wings is carried out either from one board towards the other board or from both boards alternately towards one another. Sound impulses are emitted simultaneously or alternately. Then number of caught fish is divided by total number of fish in front of trawl to determine catch efficiency.

EFFECT: improved accuracy and reliability of determination of fish amount in the trawl operating range.

2 dwg

IPC classes for russian patent Method for determination of trawl catch efficiency. RU patent 2346432. (RU 2346432):

G01S15/96 - for locating fish

A01K73/02 - Trawling nets

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