Programmable acoustic system for preventing whale and guinea pigs from being caught in fishery and operation method

Abstract

The invention discloses a programmable acoustic system for preventing whale dolphin animals from being caught in fishery and an operation method. The programmable acoustic system comprises a power supply unit, a man-machine interaction unit, a signal control unit, a digital-to-analog conversion unit, a power amplification unit, a signal transmission unit and a signal emission unit. Wherein the power supply unit is used for supplying power to the whole system; the man-machine interaction unit is used for receiving an instruction or programming content from a user; the signal control unit is used for generating a digital sound signal according to an instruction or programming content; the digital-to-analog conversion unit is used for converting a digital signal easy to operate by a system into an analog signal easy to transmit; the power amplification unit is used to amplify the analog signal generated by the system to an intensity sufficient to prevent biont compulsory capture without causing damage to animals in the target area. The device has a programmable characteristic, and supports a user to adjust the characteristics of a transmitted signal within a certain range, so that the reduction of repelling benefits caused by learning of whale and guinea pigs is prevented, and the sustainability of fishery and fishing prevention is improved.

Description

Technical Field

[0001] The present invention relates to the field of preventing bycatch of fishery organisms, and particularly to a programmable acoustic system and an operation method for preventing bycatch of cetaceans in fishery operations. Background Art

[0002] Pelagic economic fish provide a large amount of high-quality protein sources and are important food sources for many countries around the world, especially for coastal areas and fishing countries. However, in fishing operations, non-target species represented by cetaceans often gather near economic fish schools due to their predation needs, making it extremely easy to occur bycatch, which greatly affects normal production fishing activities. Accidental bycatch in fishing activities not only causes harm to the bycaught animals, but may also lead to legal and economic problems. Measures to prevent bycatch of cetaceans in fishery operations can not only reduce bycatch and protect cetacean organisms, but also improve the efficiency of fishery, achieving a win-win situation for ecological protection and economic benefits.

[0003] To avoid bycatch of cetaceans, there are some existing methods for driving away cetaceans. For example, the Chinese patent "A dolphin acoustic protection device based on medium and high frequency signals and its protection method", patent number: CN201711213719.3, uses signals of three specific frequencies and specific waveforms to protect cetaceans from bycatch. This patent has a good effect of protecting Chinese white dolphins and Irrawaddy dolphins from bycatch, but for other cetacean organisms, there is no clear conclusion indicating its effect of protecting from bycatch; the Chinese patent "A broadband acoustic signal dolphin acoustic driving-away method and system for fishing operation waters", patent number: CN202110989561.9, uses broadband signals to acoustically drive away dolphins. This solution can emit a wider band of acoustic signals and can protect more categories of cetacean organisms from bycatch. However, cetaceans have extremely strong learning abilities. In practical applications, when using specific signals to drive away cetacean organisms for a long time, the acoustic signals are often emitted during fishing operations, making the cetacean organisms learn that the sound signals often appear together with food, which will make the preventive effect of the signals on bycatch worse and even have a counterproductive effect.

[0004] In view of the problems existing in the above-mentioned existing solutions, the present invention proposes a programmable acoustic system and an operation method for preventing bycatch of cetaceans in fishery operations, which can effectively solve the above technical problems. Summary of the Invention

[0005] The present invention provides a programmable acoustic system and an operation method for preventing bycatch of cetaceans in fishery operations, which can generate digital acoustic signals through a signal control unit according to instructions or programming content, and the variable acoustic signals can effectively avoid the situation where the preventive effect of bycatch becomes worse due to the learning of cetacean organisms.

[0006] The solution of the present invention mainly includes the following content:

[0007] A programmable acoustic system for preventing the bycatch of cetaceans in fisheries, comprising an above-water machine module and an underwater machine module. The above-water machine module is used to receive instructions from the user, generate effective signals according to the instructions, and supply power to the entire system by connecting to ship electricity. The underwater machine module is used to transmit the effective signals generated by the above-water machine to underwater and emit them. The above-water machine module includes a power supply unit, a human-machine interaction unit, a signal control unit, a digital-to-analog conversion unit, and a power amplification unit. The underwater machine module includes a signal transmission unit and a signal emission unit.

[0008] Furthermore, the power supply unit of the above-water machine module is used to supply power to the entire programmable acoustic system. The human-machine interaction unit is used to receive instructions or programming content from the user. The signal control unit is used to generate digital acoustic signals according to the instructions or programming content. The digital-to-analog conversion unit is used to convert digital signals that are easy to operate by the programmable acoustic system into analog signals that are easy to emit. The power amplification unit is used to amplify the analog signals generated by the programmable acoustic system to an intensity sufficient to prevent bycatch of organisms without causing damage to the main target organisms in the target area. The power supply unit of the above-water machine module takes the alternating current supplied by the ship's generator as input. Part of it generates low-voltage direct current through AC-DC conversion, step-down, and voltage regulation to support the operation of the above-water machine module. Part of it generates alternating current with an initial level through step-down, voltage regulation, and modulation to support the operation of the underwater machine module.

[0009] Furthermore, the options supported by the human-machine interaction unit of the above-water machine module include: power on / off, preset signal group, custom signal group, set signal parameters, set emission mode.

[0010] Further, the on / off switch is used to control whether the power supply unit supplies power to the programmable acoustic system; the preset signal group is used to set the content of the transmitted signal to the signal group pre-stored in the programmable acoustic system. When the device leaves the factory, 10 groups of different types of signals are preset according to the ship attributes, operating sea areas, and common bycatch species of the assigned fishing boat. When the preset signal group is enabled, the transmitted signal is selected from the preset 10 groups of signals; the custom signal group is used to set the content of the transmitted signal to the user-defined signal group. During the use of the device, the user can customize up to 10 groups of different types of signals within a certain range according to the use requirements. When the custom signal group is enabled, the transmitted signal is selected from the custom signal group; the setting signal parameter is used to set the parameters of the custom signal, and the settable signal parameters include the blank time of the signal head, the expulsion signal time, the expulsion signal frequency, the expulsion signal energy, and the blank time of the signal tail; the setting transmission mode is used to set the signal transmission mode, and two modes of sequential cycle and random cycle are provided. The sequential cycle will transmit each group of signals in the selected signal group in a fixed order, and the random cycle will randomly select signals from the selected signal group for transmission.

[0011] Furthermore, the signal transmission unit of the underwater machine module is used to transmit signal driving power to the underwater signal transmitting unit; and the signal transmitting unit is used to transmit the acoustic signal to the target area.

[0012] Furthermore, the programmable acoustic system supports both fixed frequency and variable frequency modes, and can set 10 groups of shortcut modes. In the variable frequency mode, you can edit parameters such as frequency, emission time, stop time, and number of emissions. In the fixed frequency mode, 10 fixed frequency shortcut modes are provided. After the setting is completed, the set frequency signal will be played in a loop; the emission frequency range is limited to 4k-35kHz; the emission energy is limited to less than 180dB reμPa ("reμPa" is often used as a reference benchmark for sensitivity units, indicating the voltage output relative to 1 microPascal (μPa) sound pressure); the duration of a single expulsion signal is limited to less than 2s, and the continuous working time is less than 30min. When the working time exceeds 30min, the programmable acoustic system will be locked for 10min.

[0013] A method of operating a programmable acoustic system for preventing bycatch in cetacean fisheries comprises the following steps:

[0014] (1) Underwater machine deployment: When the user is performing fishing operations in a fishing ground and finds that there is a risk of bycatch of cetaceans and dolphins in the operation area, the underwater machine module is deployed to a suitable operation location. The programmable acoustic system must be turned off before deployment and turned on after deployment. The operation location is required to be 0.5m below the bottom of the ship and as far away from the sonar fish finder as possible;

[0015] (2) Watercraft settings: The user programs the programmable acoustic system on the human-machine interaction unit according to the on-site operation requirements, sets the characteristics of the transmission signal and the signal transmission mode. The programmable acoustic system will execute the signal transmission program within certain rules to drive away cetaceans to prevent biological bycatch. The rules defined by the programmable acoustic system mainly limit the transmission frequency range to 4k-35kHz, limit the transmission energy to below 180dB reμPa, limit the duration of a single drive-away signal to less than 2s, and the continuous working time to less than 30min. If the working time exceeds 30min, the programmable acoustic system will be locked for 10min.

[0016] (3) Monitoring of expulsion effects: When the programmable acoustic system is executing the expulsion program, the user should keep an eye on the activities of cetaceans in the operation area and record the species of cetaceans observed, their distance from the net, and whether there is any predation behavior;

[0017] (4) Setting correction: Based on the results of the repelling effect monitoring record, if it is found that the repelling effect has decreased, the setting parameters set by the watercraft are adjusted to ensure that the repelling effect of the programmable acoustic system is effective in the long term;

[0018] (5) Underwater machine recovery: After the fishing operation is completed, the underwater machine is returned to the ship and shut down before the recovery operation.

[0019] Furthermore, before the underwater machine is deployed in step (1), the on / off option should be kept in the off state, and the machine can be turned on only after it is launched into the water; before the underwater machine is recovered in step (5), the on / off option should be turned off first, and then the underwater machine is recovered out of the water to ensure that the signal transmitting unit is powered only when it is in the water, to prevent it from working in the air for a long time, causing energy accumulation and causing damage to components.

[0020] Furthermore, in step (1), when deploying the underwater machine, it is required to be 0.5m below the bottom of the ship and as far away from the sonar fish finder as possible to prevent the hull from blocking the signal and to prevent interference to the sonar fish finder when transmitting the signal.

[0021] Furthermore, the programmable acoustic system executes the signal transmission program within certain rules, including a series of mandatory frequency limits, energy limits and duration limits built into the system, specifically:

[0022] Frequency limit: The frequency limit is between 4kHz and 35kHz, which covers the hearing sensitivity threshold of common toothed whales and meets the operational needs of various sea areas. Expanding the frequency limit range will increase the cost of equipment and will not improve the effect of driving away target organisms. Therefore, the frequency range of 4kHz to 35kHz is a better choice in terms of cost-effectiveness (the ratio of effect to input cost);

[0023] Energy limit: The energy limit is below 180dB reμPa. The purpose of this energy limit is to ensure that the health and safety of the target organisms are guaranteed while achieving the premise of driving away the target organisms. Cetaceans and dolphins that are susceptible to bycatch in fishery operations are usually protected animals and are strictly protected by international fishery-related organizations and relevant laws and regulations of my country. Therefore, the maximum energy of the transmitted signal is limited to prevent them from being harmed;

[0024] Duration limit: The duration of the expulsion signal shall not exceed 2s, and the continuous working time of the system shall not exceed 30min. If it works continuously for 30min, the system will be automatically forced to shut down and lock for 10min. After unlocking, the transmission signal can be reset. The purpose of this time limit is not only to ensure the health and safety of the target organisms, but also to extend the service life of the system to a certain extent.

[0025] The present invention has the following effects and advantages:

[0026] (1) The present invention drives away cetaceans gathered during offshore fishing operations by using acoustic signals to prevent bycatch of non-target organisms. It is a non-contact driving away method. By emitting acoustic signals of a certain frequency and intensity into the sea, non-target animals are stimulated within their auditory sensitivity range, forcing them to stay away from fishing operations and avoiding harm to non-target animals as much as possible. This not only helps protect cetaceans, but also helps fishermen avoid relevant legal risks and reduce economic losses caused by bycatch and release.

[0027] (2) The present invention has two modes: system preset signal parameters and user-defined signal parameters. Different expulsion signals can be emitted according to specific application scenarios. On the one hand, targeted expulsion can be implemented for different types of cetaceans. On the other hand, flexible and changeable customized signals can be used to prevent non-target animals from learning expulsion signals, thereby avoiding the problem of reduced expulsion efficiency during long-term expulsion.

[0028] (3) The present invention implements certain mandatory restrictions on signal emission characteristics within the system, fully considering the welfare of cetaceans as protected animals, constrains custom operations, prevents operators from over-setting parameters, and avoids damage to cetaceans caused by long-term high-power drive-away acoustic signals as much as possible. BRIEF DESCRIPTION OF THE DRAWINGS

[0029] Figure 1 It is a schematic diagram of the module structure of a programmable acoustic system for preventing bycatch of cetaceans in fisheries according to the present invention.

[0030] Figure 2 The present invention is a flowchart of the programmable acoustic system for preventing bycatch of cetaceans in fisheries.

[0031] Figure 3 It is a schematic diagram of the operation interface of the human-computer interaction unit in one embodiment.

[0032] Figure 4 It is a schematic diagram of a signal transmission structure in an embodiment.

[0033] Figure 5 It is a flow chart of an operation method in one embodiment. DETAILED DESCRIPTION

[0034] The following is a detailed description of an embodiment of the present invention in conjunction with the accompanying drawings: This embodiment is implemented on the premise of the technical solution of the present invention, and a detailed implementation method and a specific operation process are given, but the protection scope of the present invention is not limited to the following embodiments.

[0035] To facilitate understanding by those skilled in the art, the present invention is now described in further detail with reference to the accompanying drawings:

[0036] See also Figure 1 As shown, the present invention discloses a programmable acoustic system for preventing bycatch of cetaceans in fisheries, comprising 1 above-water machine module and 2 underwater machine modules;

[0037] Further, 1 the waterplane module includes 11 a power supply unit, 12 a human-machine interaction unit, 13 a signal control unit, 14 a digital-to-analog conversion unit, 15 a power amplifier unit, and the five units are integrated in 16 a waterplane module housing, 12 the human-machine interaction unit, 13 the signal control unit, 14 a digital-to-analog conversion unit, 15 a power amplifier unit, 21 a signal transmission unit, and 22 a signal transmission unit are connected in sequence;

[0038] Furthermore, the underwater machine module 2 includes a signal transmission unit 21 and a signal transmission unit 22.

[0039] See also Figure 2 As shown, the present invention discloses a programmable acoustic system for preventing bycatch of cetaceans in fisheries, and the working process of the system is carried out in sequence between a power supply unit 11, a human-computer interaction unit 12, a signal control unit 13, a digital-to-analog conversion unit 14, a power amplification unit 15, a signal transmission unit 21, and a signal transmission unit 22.

[0040] Furthermore, the power supply unit 11 is a voltage-stabilized power supply that supports 220V input and converts to 12V and 5V output. One end provides a triangle plug for connecting to the ship's power supply, and the other end is simultaneously connected to the 12 human-machine interaction unit, the 13 signal control unit, the 14 digital-to-analog conversion unit, the 15 power amplifier unit, and the 2 underwater machine modules.

[0041] Further, see Figure 3As shown, the human-computer interaction unit 12 is used to receive instructions or programming content from the user, and includes an operation interface with multiple information display windows and control buttons;

[0042] Further, the signal control unit 13 generates a digital sound signal according to the instruction or programming content received by the human-machine interaction unit 12, and the system automatically and forcibly limits the transmission frequency range to 4k-35kHz, limits the transmission energy to below 180dB reμPa, limits the duration of a single expulsion signal to less than 2s, and the continuous working time to less than 30min. When the working time exceeds 30min, the system will be forced to shut down for 10min;

[0043] Further, the digital-to-analog conversion unit 14 converts the digital sound signal generated by the signal control unit 13 into an analog sound signal;

[0044] Further, the power amplification unit 15 performs power amplification on the analog sound signal generated by the digital-to-analog conversion unit 14 to achieve a specified emission intensity;

[0045] Furthermore, the signal transmission unit 21 is a roll of a load-bearing submarine cable and a matching standard waterproof submarine cable connector, one end of which is connected to the 15 power amplifier unit of the 1 above-water module, and the other end is connected to the 22 signal transmitting unit of the 2 underwater module, for transmitting the sound electrical signal generated by the 15 power amplifier unit to the 22 signal transmitting unit underwater;

[0046] Furthermore, the 22 signal transmitting unit is a packaged scalar omnidirectional underwater acoustic transducer, whose basic material is piezoelectric ceramics, supporting an operating frequency band of 10 to 48 kHz, and is used to convert the sound electrical signal delivered by the 21 signal transmission unit into an acoustic signal and broadcast it non-directionally into the ocean.

[0047] and Figure 1 Corresponding to the system, the present invention also discloses an operating method of a programmable acoustic system for preventing bycatch of cetaceans in fisheries. The method flow is shown in Figure 5 As shown, the following steps are included:

[0048] S1 underwater machine deployment: When the user is performing fishing operations in a fishing ground, if there is a risk of bycatch of cetaceans and dolphins in the operation area, the underwater machine module is deployed to a suitable operation site. The system must be turned off before deployment and turned on after deployment. The operation site is required to be 0.5m below the bottom of the ship and as far away from the sonar fish finder as possible;

[0049] Further, in a specific embodiment, when the fishermen are carrying out the offshore economic fish fishing operation, they find that there are several dolphins in the range of the net deployment, and they are hunting in groups. The fishermen connect the two ends of the signal transmission unit 21 to the power amplifier unit 15 and the signal transmission unit 22 respectively, and tie the signal transmission unit 22 to the middle of the net, and deploy the entire 2 underwater machine module together with the fishing net into the sea. After it is in place, the power supply unit 11 is connected to the ship's power supply to power on the system, see Figure 4 .

[0050] S2 watercraft settings: The user programs the acoustic system on the human-machine interface unit according to the on-site operation requirements, sets the characteristics of the transmitted signal and the signal transmission mode. The system will execute the signal transmission program within certain rules to drive away cetaceans to prevent biological bycatch.

[0051] Furthermore, in a specific embodiment, when fishermen arrive at a fishing ground for the first time to work, they select the fixed frequency mode on the operation interface, and the system reads 10 different pre-stored expulsion audios and plays them in a loop. After the system plays for 30 minutes, it automatically stops playing, and automatically starts playing after 10 minutes, in a cycle.

[0052] S3 Expulsion effect monitoring: When the system executes the expulsion program, the user should keep observing the activities of cetaceans in the operation area, and record information such as the species of cetaceans observed, the distance from the net, and whether there is any predation behavior.

[0053] Furthermore, in a specific embodiment, fishermen use a telescope to observe the activities of dolphins during the operation of the system. In the first two weeks of operation in a certain fishing ground, the dolphins always maintain a distance of 10 to 30 meters from the operation area, and the bycatch prevention effect is good. At this time, the fishermen do not need to perform the S4 setting correction.

[0054] Furthermore, in a specific embodiment, as the operation time increases, after two weeks, the dolphins in the group have gradually learned the sound signals preset by the system. Fishermen use telescopes to find that the dolphins are gradually approaching the operation area and even entering the operation area to hunt. Sometimes, they gather in the operation area after the system is turned on. At this time, the fishermen need to perform S4 setting correction.

[0055] S4 Setting Correction: Based on the results of the expulsion effect monitoring records, if it is found that the expulsion effect has decreased, the setting parameters of the watercraft will be adjusted to ensure that the system's expulsion effect is effective in the long term.

[0056] Furthermore, in a specific embodiment, fishermen found that as the operation time increased, dolphins in the observed area gradually gathered in the operation area, and the bycatch prevention effect significantly deteriorated. At this time, the variable frequency mode was set on the 12 human-computer interaction units, and 10 new sound signals were set by adjusting the single signal duration, signal frequency, signal strength and other parameters. The 10 newly set sound signals were broadcasted to the sea in a loop, and dolphins were observed to leave the operation area.

[0057] S5 underwater machine recovery: After the fishing operation is completed, the underwater machine is returned to the ship and turned off before the recovery operation.

[0058] The above shows and describes the basic principles and main features of the present invention and the advantages of the present invention. It should be understood by those skilled in the art that the present invention is not limited to the above embodiments. The above embodiments and descriptions are only for explaining the principles of the present invention. Without departing from the spirit and scope of the present invention, the present invention may have various changes and improvements, which fall within the scope of the present invention to be protected. The scope of protection of the present invention is defined by the attached claims and their equivalents.

Claims

1. A programmable acoustic system for preventing bycatch in cetacean fisheries, characterized in that: It comprises an above-water machine module and an underwater machine module. The above-water machine module is used to receive instructions from the user, generate effective signals according to the instructions, and supply power to the entire system by connecting to the ship's power supply; the underwater machine module is used to transmit the effective signals generated by the above-water machine to the underwater and emit them. The above-water machine module comprises a power supply unit, a human-computer interaction unit, a signal control unit, a digital-to-analog conversion unit and a power amplification unit, and the underwater machine module comprises a signal transmission unit and a signal emission unit.

2. A programmable acoustic system for preventing bycatch of cetaceans in fisheries according to claim 1, characterized in that: The power supply unit of the watercraft module is used to supply power to the programmable acoustic system as a whole; the human-computer interaction unit is used to receive instructions or programming content from the user; The signal control unit is used to generate a digital sound signal according to instructions or programming content; The digital-to-analog conversion unit is used to convert digital signals that are easy for the programmable acoustic system to operate into analog signals that are easy to transmit; the power amplification unit is used to amplify the analog signals generated by the programmable acoustic system to an intensity sufficient to prevent biological bycatch and not cause damage to the main organisms in the target area. The power supply unit of the waterborne machine module uses the alternating current supplied by the generator on board as input, and generates a part of it through AC-DC conversion, voltage reduction and voltage stabilization to generate low-voltage direct current for supporting the operation of the waterborne machine module; and generates a part of it through voltage reduction, voltage stabilization and modulation to generate alternating current with an initial level for supporting the operation of the underwater machine module.

3. A programmable acoustic system for preventing bycatch of cetaceans according to claim 1, characterized in that: The options supported by the human-computer interaction unit of the watercraft module include: power on / off, preset signal group, custom signal group, setting signal parameters, and setting transmission mode.

4. A programmable acoustic system for preventing bycatch in cetacean fisheries according to claim 3, characterized in that: The on / off switch is used to control whether the power supply unit supplies power to the programmable acoustic system; the preset signal group is used to set the content of the transmitted signal to the signal group pre-stored in the programmable acoustic system. When the device leaves the factory, 10 groups of different types of signals are preset according to the ship attributes, operating sea areas, and common bycatch species of the assigned fishing boat. When the preset signal group is enabled, the transmitted signal is selected from the preset 10 groups of signals; the custom signal group is used to set the content of the transmitted signal to the user-defined signal group. During the use of the device, the user can customize up to 10 groups of different types of signals within a certain range according to the use requirements. When the custom signal group is enabled, the transmitted signal is selected from the custom signal group; the setting signal parameter is used to set the parameters of the custom signal. The settable signal parameters include the blank time of the signal head, the expulsion signal time, the expulsion signal frequency, the expulsion signal energy, and the blank time of the signal tail; the setting emission mode is used to set the signal emission mode, and two modes of sequential cycle and random cycle are provided. The sequential cycle will emit each group of signals in the selected signal group in a fixed order, and the random cycle will randomly select signals from the selected signal group for emission.

5. A programmable acoustic system for preventing bycatch of cetaceans according to claim 1, characterized in that: The signal transmission unit of the underwater machine module is used to transmit signal driving power to the underwater signal transmitting unit; the signal transmitting unit is used to transmit the acoustic signal to the target area.

6. A programmable acoustic system for preventing bycatch in cetacean fisheries according to claim 1, characterized in that: The programmable acoustic system supports both fixed frequency and variable frequency modes. 10 groups of shortcut modes can be set. In the variable frequency mode, parameters such as frequency, emission time, stop time, and number of emissions can be edited. In the fixed frequency mode, 10 fixed frequency shortcut modes are provided. After the setting is completed, the set frequency signal will be played in a loop; the emission frequency range is limited to 4k-35kHz; the emission energy is limited to below 180dB reμPa; the duration of a single expulsion signal is limited to less than 2s, and the continuous working time is less than 30min. When the working time exceeds 30min, the programmable acoustic system will be locked for 10min.

7. A method of operating a programmable acoustic system for preventing bycatch in cetacean fisheries as claimed in claim 1, characterized in that: The following steps are involved: (1) Underwater machine deployment: When the user is performing fishing operations in a fishing ground and finds that there is a risk of bycatch of cetaceans and dolphins in the operation area, the underwater machine module is deployed to a suitable operation location. The programmable acoustic system must be turned off before deployment and turned on after deployment. The operation location is required to be 0.5m below the bottom of the ship and as far away from the sonar fish finder as possible; (2) Watercraft settings: The user programs the programmable acoustic system on the human-machine interaction unit according to the on-site operation requirements, sets the characteristics of the transmission signal and the signal transmission mode. The programmable acoustic system will execute the signal transmission program within certain rules to drive away cetaceans to prevent biological bycatch. The rules defined by the programmable acoustic system mainly limit the transmission frequency range to 4k-35kHz, limit the transmission energy to below 180dB reμPa, limit the duration of a single drive-away signal to less than 2s, and the continuous working time to less than 30min. If the working time exceeds 30min, the programmable acoustic system will be locked for 10min. (3) Monitoring of expulsion effects: When the programmable acoustic system is executing the expulsion program, the user should keep an eye on the activities of cetaceans in the operation area and record the species of cetaceans observed, their distance from the net, and whether there is any predation behavior; (4) Setting correction: Based on the results of the repelling effect monitoring record, if it is found that the repelling effect has decreased, the setting parameters set by the watercraft are adjusted to ensure that the repelling effect of the programmable acoustic system is effective in the long term; (5) Underwater machine recovery: After the fishing operation is completed, the underwater machine is returned to the ship and shut down before the recovery operation.

8. The method of operating a programmable acoustic system for preventing bycatch in cetacean fisheries according to claim 7, characterized in that: Before deploying the underwater machine in step (1), the on / off option should be kept in the off state, and the machine can be turned on only after it is launched into the water. Before recovering the underwater machine in step (5), the on / off option should be turned off first, and then the underwater machine is recovered and removed from the water body to ensure that the signal transmitting unit is powered only when it is in the water, to prevent it from working in the air for a long time, causing energy accumulation and causing damage to components.

9. The method of operating a programmable acoustic system for preventing bycatch in cetacean fisheries according to claim 7, characterized in that: In step (1), when deploying the underwater machine, it is required to be 0.5m below the bottom of the ship and as far away from the sonar fish finder as possible to prevent the hull from blocking the signal and to prevent interference to the sonar fish finder when transmitting the signal.

10. The method of operating a programmable acoustic system for preventing bycatch in cetacean fisheries according to claim 7, characterized in that: The programmable acoustic system executes the signal transmission program within certain rules, including a series of mandatory frequency limits, energy limits and duration limits built into the system, specifically: Frequency limit: The frequency limit is between 4kHz and 35kHz, which covers the hearing sensitivity threshold of common toothed whales and meets the operation requirements of various sea areas. Expanding the frequency limit range will increase the equipment cost and will not improve the effect of driving away target organisms. Therefore, the frequency range of 4kHz to 35kHz is a more cost-effective choice; Energy limit: The energy is limited to below 180dB reμPa. The purpose of this energy limit is to ensure that the health and safety of the target organisms are guaranteed while achieving the premise of driving away the target organisms. The maximum energy of the transmitted signal is limited to prevent them from being harmed. Duration limit: The duration of the expulsion signal shall not exceed 2s, and the continuous working time of the system shall not exceed 30min. It can also extend the service life of the system to a certain extent.

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