FIELD: hydroacoustic engineering.
SUBSTANCE: method involves effectively operatively counting and sorting invertebrates with their sex, size, mechanical injury degree and other signs taking into account. A part of the invertebrates is placed into control traps of study purpose in the amount of at least 10 individuals per trap sorted according to abovementioned signs. Required fodder amount is given for feeding the invertebrates in the control traps having in view the time they are to be kept in the control traps. All the control traps are connected to each other with a ridge member having negative floating capacity. Signal buoy is placed in water space. To provide the buoy floating up to the seawater surface, cable rope is placed between two guiding members on command given. Signals of invertebrates are transmitted via hydroacoustic channel by means of autonomous unit for recording and transmitting the signals of invertebrates placed in the signal buoy and by means of the first commutator and acoustic transducer of the signal buoy, towards omnidirectional echo-ranging transducer placed at given depth with rope from research vessel board. The signals are received by means of electrically in series connected omnidirectional echo-ranging transducer, cable rope, the second commutator, amplifier and solver unit. Encoded control signal emission causing signal buoy rise to the surface is carried out by applying electrically in series connected master clock, power amplifier, the second commutator, cable rope and omnidirectional echo-ranging transducer. Encoded hydroacoustic control signals are received, amplified and decoded by means of electrically in series connected acoustic transducer, the first commutator, amplifier, signal buoy decoder. The signal f is sent to electromagnetic relay for operating mechanical break switch of the signal buoy. The buoy starts rising to the seawater surface on receiving signal. Floating signal buoy is visually looked for and using vessel navigation station. Research order of the control traps is lifted onto research vessel board by means of research vessel sampling device. After having lifted the research order of the control traps onto research vessel board, survived (dead) invertebrate individuals are counted and estimated in per cent scale, the total number of survived or dead invertebrate individuals (with earlier released invertebrate individuals taken into account) after having released them free into the sea from poaching ship board under given geographic, season, climate hydroacoustic conditions and other conditions.
EFFECT: high counting accuracy; simplified estimation method.
7 dwg
