A system and method for wild rearing of orange roughy

Abstract

The application provides a wild domestication system and method for yellowlip croaker, and belongs to the technical field of endangered fish germplasm resource repair and conservation. Through simulation of a natural environment, the yellowlip croaker is subjected to food sensitivity training, ecological inversion adaptability training, instantaneous cruising ability and adversity adaptability training, so that the feeding and starvation resistance of the released yellowlip croaker are enhanced, and the survival abilities such as disaster avoidance and stress reduction are improved, so that the survival rate of the yellowlip croaker in a natural sea area after release is improved. The system and technical method for simulating a natural environment according to the application have a good proliferation effect on the release of the yellowlip croaker, and have a wide application prospect.

Description

TECHNICAL FIELD

[0001] The present application belongs to the technical field of endangered fish germplasm resource repair and conservation, and particularly relates to a wild domestication system and method for Bahaba taipingensis. BACKGROUND

[0002] Bahaba taipingensis belongs to the order Perciformes, the family Sciaenidae, and the genus Bahaba, and is a large warm-temperate bottom-dwelling fish in the coastal area. They often inhabit the estuary where seawater and freshwater meet, and prefer deep water with suitable fish reefs and water flow. As a unique fish species in China, its distribution range is limited to the northern South China Sea and the southern East China Sea, and it is particularly common in the Pearl River Estuary. However, in recent years, overfishing and habitat destruction have caused a sharp decline in the population of Bahaba taipingensis, which has been listed as a nationally protected animal and is classified as "Critically Endangered (CR)" in the IUCN Red List of Endangered Species. It is the only marine fish listed as a nationally protected animal.

[0003] The biodiversity of Bahaba taipingensis is crucial in the marine ecological chain and is an important part of the coastal food chain, which is of great significance to the stability and balance of the coastal ecological environment. However, overfishing and habitat destruction have further exacerbated the decline of its population, and to repair and protect this precious species, the release of the population has become a key measure, which is expected to gradually restore the biodiversity of Bahaba taipingensis and increase its population. However, the artificially bred Bahaba taipingensis lacks the ability to adapt to the natural environment, and direct release will greatly reduce the survival rate of Bahaba taipingensis. Past wild training experience mainly focuses on environmental adaptation training and survival skill training. For example, the wild-like Pachyngathogobio domestication method disclosed in patent CN107432261A simulates the low-temperature and high-oxygen content environment in which Pachyngathogobio lives to domesticate it. Introducing a predator model is also an important way to adapt to the environment, such as the method disclosed in patent CN103329829A, which uses a predatory fish or an electric mechanical arm to scare the fry to improve their ability to avoid being caught. However, the behavior patterns and ecological habits of the predators that Bahaba taipingensis faces in the natural environment, such as sharks and Chinese white dolphins, are very different from those of general fish predators, and it is difficult to simulate them in an artificial domestication environment, making it difficult to implement this method in the wild training of Bahaba taipingensis. In addition, survival skill training is also important for the wild training of Bahaba taipingensis. A common approach is to feed live bait (such as water fleas and insect larvae) to train the ability to catch prey, such as the method disclosed in patent CN114532256A, which uses male live red worms to train the ability of wild Pungtungia niphes to catch prey. However, the feeding habits of Bahaba taipingensis are complex, and the way it catches prey is unique, so the training methods for other fish cannot be simply applied.

[0004] Due to the unique biological characteristics of the Megalobrama amblycephala, the wild domestication work of the large Sciaenidae is still in its infancy, and faces many problems. So far, there is no systematic and effective solution, which has become a major obstacle to the population restoration and protection of the Megalobrama amblycephala. Therefore, the development of the wild domestication system and method of the Megalobrama amblycephala has become a problem to be solved. SUMMARY

[0005] To solve the above technical problems, the present application provides a wild domestication system and method of Megalobrama amblycephala, which improves the survival rate and stress resistance of released Megalobrama amblycephala.

[0006] In order to achieve the above-mentioned application purposes, the present application provides the following technical solutions:

[0007] The present application provides a wild domestication system of Megalobrama amblycephala, wherein the wild domestication system of Megalobrama amblycephala fry comprises a domestication soil pool and a circulating water treatment system; the domestication soil pool is divided into a pit and depression terrain water area, a shallow water area, a steep slope water area and a deep water area; the pit and depression terrain water area is provided with a water inlet of the circulating water treatment system, and the deep water area is provided with a water outlet of the circulating water treatment system; the domestication soil pool is further provided with light, sound and flow environmental factor equipment and monitoring equipment.

[0008] As an embodiment, the shallow water area accounts for 30% to 50% of the area of the domestication soil pool; the deep water area accounts for 25% to 35% of the area of the domestication soil pool; the steep slope water area accounts for 5% to 15% of the area of the domestication soil pool; and the pit and depression terrain water area accounts for 10% to 30% of the area of the domestication soil pool.

[0009] Preferably, the pool body shape of the domestication soil pool is rectangular or square, the length-width ratio is (2-4):3, and the maximum depth is 3.5 m.

[0010] Preferably, the ratio of sand and soil of the bottom of the domestication soil pool is 1:(0.5-1.5).

[0011] Preferably, the pit and depression terrain water area has a circular or nearly circular pit and depression form with a diameter of 1-2 m.

[0012] Preferably, the average water depth of the shallow water area is 1-2 m; the average water depth of the deep water area is 2.5-3.5 m; and the average water depth of the pit and depression terrain water area is 1.5-2.0 m.

[0013] In the present application, the pit and depression terrain water area is adjacent to the shallow water area and / or the steep slope water area; the steep slope water area is inclined to extend from the shallow water area to the deep water area, and the inclination slope is 60-80 degrees.

[0014] As an embodiment, the light, sound, and flow environmental factor device is a light source device, an audio device, and a variable frequency submersible pump, the light source device can adjust light intensity and color temperature, the light source device and the audio device are located above or below the domesticated soil pool water area, and the water pump is located below the domesticated soil pool water area.

[0015] Preferably, the light source device is a waterproof LED or COB light source.

[0016] As an embodiment, the circulating water treatment system comprises a mechanical particle rolling barrel filter, a gas tank, an upflow anaerobic tower, and a variable frequency submersible pump connected by pipelines, and the gas tank is provided with a flotation machine.

[0017] The application also provides a wild yellowlip fish domestication method based on the foregoing system, the temperature and salinity of the water in the domesticated soil pool are adjusted to adapt to the cultivation of yellowlip fish, and the yellowlip fish is put into the pool for feeding domestication and environmental adaptation domestication; the feeding domestication is intermittent fasting domestication, and food species are replaced and fed in a gradually increasing amount; the environmental adaptation domestication comprises one or more of anti-flow stress domestication, anti-noise stress domestication, anti-light stress domestication, and enhanced hiding domestication.

[0018] Preferably, the domestication period of the feeding domestication or the environmental adaptation domestication is 28-40 days.

[0019] Further, the intermittent fasting domestication adopts a cycle mode of “1-time feeding per day + 4-day fasting”, one food species is fed each time, and the feeding amount is increased in a gradient of 10%, 40%, 70%, 100%, and 130% of the fish body weight.

[0020] Preferably, the food species comprises live small shrimp and crab species, live or fresh miscellaneous fish, and fresh cephalopods.

[0021] Preferably, the live or fresh miscellaneous fish comprises dragonhead fish, needlefish, leaf fish, sharphead fish, and golden threadfish.

[0022] Preferably, the fresh cephalopods comprise squid and cuttlefish.

[0023] Further, the anti-flow stress domestication gradually increases the flow rate of the water from 0.01 m / s to 1 m / s, and when the yellowlip fish reaches a critical balance position in the reverse flow movement, the flow rate is maintained for 30-60 minutes; the anti-noise stress domestication is to play ship noise; the anti-light stress domestication adopts a mode of instantaneous strong light, then gradually dark, until the original light intensity is restored, or an instantaneous cold light gradually changes to warm light; and the hiding domestication is mechanical touch immediately after the anti-noise stress domestication, or the anti-noise stress domestication is combined with the anti-flow stress domestication or the anti-light stress domestication.

[0024] Preferably, the intensity of the light in the anti-light stress domestication ranges from 0 to 2000 Lx, the color temperature of the cool light ranges from 5000 to 6500 K, and the color temperature of the warm light ranges from 2000 to 3000 K.

[0025] As an implementation form, the circulating water treatment system of the wild domestication system of the golden threadfin bream is started to operate 7 to 10 weeks before wild domestication.

[0026] As an implementation form, the temperature of the pool water of the wild domestication system of the golden threadfin bream is 20 to 28 DEG C, the salinity is 2.0 to 15.0, the pH is 7.2 to 7.6, the dissolved oxygen content is more than 6 ml / L, the ammonia nitrogen content is less than 0.2 mg / L, the water pump is opened for 2 to 4 hours and closed for 2 hours, the circulation is performed 4 to 6 times per day, and the flow rate in the pool is kept below 0.05 m / s when the water pump is opened.

[0027] As an implementation form, the number of the golden threadfin bream in the domestication soil pool is 5% to 15% of the number of the blue gourami.

[0028] Preferably, the golden threadfin bream is 12 to 16 months old and has a body length of more than 20 cm.

[0029] Preferably, the input amount of the golden threadfin bream is 0.5 to 0.75 kg / m 3 .

[0030] Compared with the prior art, the present application has the following beneficial effects:

[0031] The present application constructs a wild domestication system of the golden threadfin bream, which simulates the natural sea bottom landform features of the habitat of the golden threadfin bream, constructs a soil pool simulating a natural environment, divides the water area of the pit and depression terrain, the shallow water area, the steep slope water area and the deep water area where the golden threadfin bream survives, and combines and designs the circulating water treatment system, the environmental factor equipment and the monitoring equipment. With the aid of the system, the main ecological environmental factors such as sound, light and flow can be stimulated. At the same time, the system also statistically analyzes the video and image of the behavior change of the golden threadfin bream in the wild domestication process, accumulates basic data, and provides a reference basis for studying the growth and development and adaptability evaluation of the released fish after entering the sea.

[0032] In addition, the present application also provides a wild domestication method of the golden threadfin bream, which gradually improves the wild recovery and survival ability of the released golden threadfin bream fry from the aspects of ecological environment adaptation, bait type conversion, predation performance improvement and disaster avoidance, and provides a feasible technical route and implementation scheme for protecting the survival rate of the released golden threadfin bream. By using the system and method of the present application, the purpose of protecting the golden threadfin bream can be effectively achieved, the stress resistance of the golden threadfin bream is improved, and a solid foundation is laid for the recovery and growth of the golden threadfin bream population. BRIEF DESCRIPTION OF DRAWINGS

[0033] Figure 1 This is a top-down schematic diagram of the yellow croaker rewilding and domestication system. 1-Deep water area, 2-Steep slope water area, 3-Pooled water area, 4-Shallow water area, 5-Inlet, 6-Pipeline, 7-Outlet, 8-Mechanical granular drum filter, 9-Aeration tank and flotation machine, 10-Upflow anaerobic tower, 11-Variable frequency submersible pump.

[0034] Figure 2 A top-down view of the equipment for the wild domestication system of the yellow croaker, 12-monitoring equipment, 13-audio equipment, 14-variable frequency submersible pump, 15-light source equipment.

[0035] Figure 3 This is a side cross-sectional view of the wild domestication system of the yellow croaker. 1 represents deep water, 2 represents steep slope water, 3 represents water with pitted terrain, and 4 represents shallow water. Detailed Implementation

[0036] This invention provides a wild breeding system for the yellow croaker, which includes a breeding pond and a circulating water treatment system. The breeding pond is divided into a depression-topped water area, a shallow water area, a steep-slope water area, and a deep water area. The inlet of the circulating water treatment system is located in the depression-topped water area, and the outlet of the circulating water treatment system is located in the deep water area. The breeding pond is also equipped with light, sound, and flow environmental factor devices and monitoring devices.

[0037] The domestication pond described in this invention simulates the bottom texture and topography of the natural marine habitat of the yellow croaker, imitating the substrate and morphology of its natural habitat, including the microbial community structure and topography in the water and substrate, thereby achieving the purpose of wild domestication. In this invention, the substrate of the domestication pond is composed of sand and soil. The ratio of sand to soil is 1:(0.5-1.5), preferably 1:1. This invention does not particularly limit the shape of the domestication pond; in some embodiments, the pond body is rectangular or square, and the aspect ratio of the rectangle is (2-4):3, preferably 4:3. The maximum depth of the domestication pond is 3.5m.

[0038] In this invention, the breeding pond of the yellow croaker rewilding and domestication system is divided into a basin with uneven terrain, a shallow water area, a steep slope water area, and a deep water area. The shallow water area accounts for 30% to 50% of the area of ​​the breeding pond; the deep water area accounts for 25% to 35% of the area; the steep slope water area accounts for 5% to 15% of the area; and the basin with uneven terrain accounts for 10% to 30% of the area. Preferably, the shallow water area accounts for 35% to 45% of the area; the deep water area accounts for 25% to 30% of the area; the steep slope water area accounts for 5% to 10% of the area; and the basin with uneven terrain accounts for 15% to 25% of the area. In this invention, shallow water areas serve as activity zones with ample sunlight and abundant food, simulating natural shallow water environments; deep water areas act as refuge zones, helping the yellow croaker cope with extreme weather or avoid disasters; steep slope areas simulate natural terrain transition zones, training fish to adapt to changes in water flow and depth; and pitted terrain areas create complex microhabitats, promoting exploratory behavior and enhancing resilience. Preferably, the pits in the pitted terrain areas are circular or nearly circular, with a diameter of 1–2 m. Preferably, the average depth of the shallow water areas is 1–2 m, more preferably 1.3–1.8 m. Preferably, the average depth of the deep water areas is 2.5–3.5 m, more preferably 3 m. Preferably, the average depth of the pitted terrain areas is 1.5–2.0 m, more preferably 2 m. In some embodiments of this invention, the pitted terrain areas are adjacent to the shallow water areas and / or the steep slope areas; the steep slope areas extend slopingly from the shallow water areas to the deep water areas. Preferably, the inclination slope is 60 to 80 degrees, and more preferably 65 to 75 degrees.

[0039] In this invention, the light, sound, and flow environmental factor devices include a light source device, an audio device, and a variable frequency submersible pump. The light source device is adjustable in light intensity and color temperature, and it and the audio device are located above or below the water area of ​​the conditioning pond. The light source device is used to simulate the lights emitted by ships at night. Preferably, the light source device is a waterproof LED or COB light source. The audio device is used to simulate the low-frequency noise generated by the rotation of a diesel engine and propeller, or the high-frequency noise generated by the high-speed rotation of the propeller blades, as well as the noise of a ship's horn. The low-frequency noise frequency is 60–200 Hz. The high-frequency noise frequency is 1–20 kHz. The variable frequency submersible pump is located below the water area of ​​the conditioning pond. The pump can simulate the water flow rate and, through a timer, simulate the scenarios of high tide, low tide, and slack tide, while also simulating the turbulence caused by passing ships.

[0040] In this invention, the circulating water treatment system includes a mechanical granular drum filter, an aeration tank, an upflow anaerobic tower, and a variable frequency submersible pump connected by pipelines. The aeration tank is equipped with an air flotation unit. Preferably, the mechanical granular drum filter can filter out impurities with a particle diameter >200μm. The aeration tank has a depth of 1.5–2.5m, preferably 2.0m; and an area of ​​3–5m². 2 Preferably, it is 3.5–4.5m. 2 In this invention, the flotation unit in the aeration tank further removes COD and suspended solids from the water. The upflow anaerobic tower utilizes the fermentation of denitrifying bacteria in an anaerobic environment to decompose and remove organic matter such as nitrates in the water under anaerobic conditions. In this invention, the inlet of the circulating water treatment system is located in a depression-type water area, and the outlet of the circulating water treatment system is located in a deep water area. The water discharged from the outlet is filtered and diverted. The filtered sediment flows away through the sewage outlet, and the filtered water enters the mechanical granular drum filter of the circulating water treatment system for further treatment, recycling and reusing, saving water resources while ensuring the stability of the ecological environment.

[0041] In this invention, the yellow croaker rewilding and domestication system also includes monitoring equipment, which is an underwater monitoring probe. The monitoring probe transmits the video signal captured by the underwater monitoring probe to a switch or signal transmitter via a wired or wireless connection, and then supplies it to the terminal equipment via a network.

[0042] The present invention also provides a method for the wild domestication of yellow croaker based on the aforementioned system, wherein the temperature and salinity of the water in the domestication pond are adjusted to suit the cultivation of yellow croaker, and the yellow croaker are put into the pond for feeding domestication and environmental adaptation domestication.

[0043] In this invention, the circulating water treatment system of the yellow croaker rewilding and domestication system is started 7-10 weeks before rewilding and domestication. The environment of the yellow croaker rewilding and domestication system is adjusted so that the pond water temperature is 20-28℃, salinity is 2.0-15.0, pH is 7.2-7.6, dissolved oxygen is above 6ml / L, ammonia nitrogen content is below 0.2mg / L, nitrite content is below 0.01mg / L, and transparency is above 1.0m. In this invention, the variable frequency submersible pump of the circulating water treatment system is turned on / off (2-4)h / 2h, circulating 4-6 times a day, maintaining the flow velocity in the pond below 0.05m / s when turned on, so that the pond water quality meets the Class II seawater quality standard.

[0044] In this invention, the feeding training is intermittent fasting training, with alternating food types and gradually increasing feeding amounts. Preferably, the intermittent fasting training adopts a cyclical pattern of "feeding once a day + fasting for 4 days," with one type of food fed each time, and the feeding amount increasing in increments of 10%, 40%, 70%, 100%, and 130% of the fish's body weight. Preferably, the food types include live small shrimp and crabs, live or chilled miscellaneous fish, and chilled cephalopods. More preferably, the live or chilled miscellaneous fish include lizardfish, needlefish, leaffish, sharpheaded fish, and golden threadfin bream. The chilled cephalopods include squid and cuttlefish.

[0045] In this invention, the environmental adaptation training includes one or more of the following: resistance to current stress, resistance to noise stress, resistance to light stress, and enhanced avoidance training. Preferably, the resistance to current stress training involves gradually increasing the water flow rate from 0.01 m / s to 1 m / s, maintaining the flow rate for 30–60 minutes when the yellow croaker reaches a critical equilibrium position during its upstream movement. Preferably, the resistance to current stress training is repeated 2–4 times daily, 2–4 days per week. The resistance to noise stress training involves playing boat noise. Preferably, the resistance to noise stress training is conducted 2–3 times daily, for 4–10 minutes each time. The resistance to light stress training uses a sudden burst of strong light, followed by gradual dimming until the original light intensity is restored, or a sudden transition from cool light to warm light. Preferably, the light intensity range during the light stress resistance training is 0–2000 Lx, the color temperature range of the cool light is 5000–6500 K, and the color temperature range of the warm light is 2000–3000 K. Preferably, the light stress resistance training is conducted 2–3 times daily, for 5–10 minutes each time. The avoidance training involves mechanical contact immediately after noise stress resistance training, or it can be combined with noise stress resistance training or light stress resistance training during flow stress resistance training. In this invention, the acclimatization period for the feeding or environmental adaptation training is 28–40 days.

[0046] In this invention, 5% to 15% of the number of yellow croakers and spotted bluefish are co-cultured in the breeding pond to act as scavengers. Preferably, the number of spotted bluefish is 10% of the number of yellow croakers. Before the yellow croakers begin their wilding and domestication, the yellow croakers and spotted bluefish acclimatize together for 2 to 3 days. In this invention, the juvenile yellow croakers are 12 to 16 months old and have a body length of over 20 cm. The spotted bluefish have a body length of 5 to 10 cm. Preferably, the feeding rate of juvenile yellow croakers is 0.5 to 0.75 kg / m³. 3 .

[0047] This invention constructs a wild-cultivation system for the yellow croaker, establishing a complete system for its wild-cultivation. This system provides juvenile yellow croakers with a growth space as close to their natural environment as possible, enabling comprehensive feeding and environmental adaptation training. After the entire training process is completed, a testing phase begins. Various physiological conditions of the yellow croakers are tested, including but not limited to their health status and whether their various physical indicators are normal. After testing, the yellow croakers are tagged. This invention does not have specific limitations on the tagging method; considering the convenience and accuracy of data monitoring, electronic tags can be used. The tagged yellow croakers are then released into large net cages in an experimental sea area simulating a natural ecological environment, allowing them to survive naturally in a relatively natural environment to verify the actual effect of wild-cultivation.

[0048] After a period of observation and data analysis in breeding ponds, it was found that the yellow croakers raised in wild conditions did not show a significant difference in weight and length growth compared to those raised in artificial environments. This result fully demonstrates that the wilding method adopted in this invention helps the yellow croakers adapt to the natural environment without causing significant negative impacts on their normal growth, ensuring the stability of their growth and development. Further verification of the effectiveness of this method involved allowing the yellow croakers to continue natural growth for a longer period in large net cages in an experimental marine area simulating a natural ecological environment. In-depth research and analysis revealed that the method of this invention can enhance the survival ability of artificially bred yellow croakers in the wild. The survival rate of wild-raised yellow croakers reached approximately 93.3%. This result contrasts sharply with that of unraised yellow croakers, powerfully demonstrating the important value of this invention in the protection and population recovery of yellow croakers, and providing a practical technical solution for the protection and restocking of endangered yellow croakers.

[0049] Unless otherwise specified, the following embodiments are all conventional methods.

[0050] Unless otherwise specified, all materials used in the following embodiments are commercially available.

[0051] The technical solutions provided by the present invention will be described in detail below with reference to the embodiments, but they should not be construed as limiting the scope of protection of the present invention.

[0052] Example 1

[0053] Construction of Yellow Croaker Wild Rearing System

[0054] 1. Domestication pond

[0055] A pond with an area of ​​approximately 500 square meters was selected, and the topography of the acclimatization pond was constructed. The soil for the acclimatization pond was selected with a sand-gravel to soil ratio of approximately 1:1. 40% of the pond area was designated as shallow water, with an average depth of 1.5m; 30% as deep water, with an average depth of 3.0m; 10% as a steeply sloping area, constructed with bricks at a 70-degree angle; and the remaining 20% ​​was transformed into a depression-like water area, with circular depressions ranging from 1 to 2m in diameter and an average depth of 1.5 to 2.0m. Water inlets were constructed at the depressions, with two 400mm diameter pipes equipped with shut-off valves to control the water flow. An outlet was constructed at the deep water area, with drainage holes built at the bottom of the pond, connecting to 400mm pipes extending to the outside of the pond embankment, where the water was then distributed as an inlet and outlet for the circulating water treatment system.

[0056] 2. Circulating water treatment system

[0057] The circulating water treatment system consists of a mechanical granular drum filter, an aeration tank equipped with an air flotation unit, and an upflow anaerobic tower connected in series. A 4kW variable frequency submersible pump is installed at the end of the system, pumping the water back to the inlet of the acclimatization tank via pipeline. The aeration tank is 1.5m deep and 4m² in area. 2 The circulating water treatment system is started 8 weeks before the rewilding and domestication. The water temperature is maintained at 20–28℃, salinity at 2.0–15.0, pH at 7.2–7.6, dissolved oxygen above 6 ml / L, ammonia nitrogen below 0.2 mg / L, nitrite below 0.01 mg / L, and transparency above 1.0 m. The water pump is turned on / off 4 hours / 2 hours, circulating the water 4 times daily, maintaining a flow velocity below 0.05 m / s when on, and ensuring the water quality meets the Class II seawater quality standard.

[0058] 3. Equipment for monitoring light, sound, and airflow environmental factors

[0059] The light source uses waterproof LED lights, with color temperature adjusted by varying the current of the warm and cool LED strips. These lights are randomly installed in different locations both above and below the water surface. The audio system uses a high-fidelity stereo amplifier and player, with the player also randomly installed in different locations above and below the water surface. The water flow is simulated using variable frequency submersible pumps and timers. Four 2.0kW variable frequency submersible pumps are placed near the corners of the pool to circulate the water. Each pump is positioned 1.0m above the pool bottom. Variable frequency speed control simulates the water flow rate, while timers simulate high tide, low tide, and slack tide scenarios.

[0060] 4. Monitoring equipment

[0061] Composed of a computer, router, and 10 underwater monitoring probes, the cameras are low-light waterproof cameras, each installed on the inner wall of the breeding pond, 50-100cm from the bottom of the pond, to collect information on the behavioral changes of the yellow croaker from various angles. This image information is transmitted to the terminal computer device through a switch, and the fish behavior analysis system is used to analyze the changes in the swimming, feeding, and risk avoidance behaviors of the fry in order to observe and determine the adaptability of the fry.

[0062] Example 2

[0063] Yellow croaker rewilding and domestication methods

[0064] Two hundred 16-month-old artificially bred yellow croaker juveniles were taken, and their weight and body length were measured and recorded. At the same time, about 20 spotted bluefish juveniles were mixed in and put into the acclimatization pond together for two days.

[0065] Two days after being introduced into the rearing pond, the juvenile yellow croaker began feeding training. The feeding training program was as follows: Intermittent fasting training adopted a cyclical pattern of "feeding once a day + fasting for 4 days," feeding one type of food each time, with the amount of food increasing in a gradient of 10%, 40%, 70%, 100%, and 130% of the fish's body weight. The food included live small shrimp and crabs, live or frozen miscellaneous fish, and frozen cephalopods. The feeding training cycle was 30 days. The environmental adaptation training program was as follows: Current stress training: By gradually increasing the water flow rate from 0.01 m / s to 1 m / s, the yellow croaker reached a critical equilibrium point when it could no longer swim against the current. The flow rate was maintained for 45 minutes, repeated 3 times a day, 3 days a week, for 1 week. Noise stress training: Underwater playback of ship noise, with low-frequency noise at 60-200Hz and high-frequency noise at 1-20kHz, 2-3 times daily for 8 minutes each time, for 1 week. Light stress training: Instantaneous strong light followed by gradual dimming until the original light intensity is restored (2000Lx to 0Lx); or an instantaneous cold light gradually transitioning to warm light pattern, 2-3 times daily for 8 minutes each time, for 1 week. Avoidance training: Immediately after noise stress training, mechanical contact is conducted, or noise stress or light stress training is combined with current stress training, for 1 week. Environmental adaptation training lasts 28 days. After training, multiple small net cages with a volume of at least 4 cubic meters are placed in the training pond, and the juvenile yellow croakers are placed in separate small net cages. A comprehensive health check is performed on each yellow croaker, and detailed records are kept of any injuries or symptoms of stress. Simultaneously, the weight, body length, and other growth data of the yellow croaker were measured again to calculate their growth rate or weight gain rate and specific growth rate during the domestication period. Then, 30 yellow croakers were randomly selected, tagged with electronic tags, and randomly transferred to a large net cage in an experimental sea area simulating a natural ecological environment. They were not fed for the next 90 days to observe and determine whether the domesticated and wild-trained yellow croakers possessed the basic ability to survive in a simulated natural environment. Their survival and growth status were then assessed at the end of the period.

[0066] Comparative Example 1

[0067] Thirty yellow croakers, fed and domesticated for 30 days as described in Example 2, were randomly selected, tagged with electronic tags, and then transferred to a large net cage in an experimental sea area simulating a natural ecological environment. They were not fed for the following 90 days to observe and determine whether the domesticated and wild-trained yellow croakers possessed the basic ability to survive in a simulated natural environment. Their survival and growth were then assessed at the end of the experiment.

[0068] Comparative Example 2

[0069] This comparative example follows the wild rearing system for yellow croaker constructed in Example 1 and the wild rearing method for yellow croaker in Example 2. The difference from Example 2 is that this comparative example only implemented the environmental adaptation rearing stage; feeding rearing was not conducted. The rearing period lasted 28 days. After the wild rearing was completed, 30 yellow croakers were tagged electronically and transferred to a large net cage in an experimental sea area simulating a natural ecological environment for a 90-day wild rearing effect verification experiment. No food was provided during these 90 days, and survival and growth were monitored after the experiment.

[0070] Comparative Example 3

[0071] This comparative experiment was conducted using the wild rearing system for yellow croaker constructed in Example 1 and the wild rearing method for yellow croaker in Example 2. The difference from Example 2 is that a cyclical pattern of "feeding once every 2 days + fasting for 3 days" was adopted. The amount of food fed each time was increased in increments of 10%, 30%, 60%, 90%, and 120% of the fish's body weight, while the type of food remained the same. The experiment lasted for 30 days. Environmental adaptation was the same as in Example 2. After the experiment, 30 wild-raised yellow croakers were randomly selected and transferred to a large net cage in a simulated natural ecological environment for a 90-day wild rearing effect verification experiment. No food was provided during this period, and survival and growth were assessed after the experiment.

[0072] Comparative Example 4

[0073] This comparative example follows the wild rearing system for yellow croaker constructed in Example 1 and the wild rearing method for yellow croaker in Example 2. The difference from Example 2 is that the environmental adaptation rearing phase in this comparative example does not include avoidance training or noise stress resistance training; instead, current stress resistance training and light stress resistance training are conducted for 14 days each. After the experiment, 30 wild-raised yellow croakers were randomly selected and transferred to a large net cage in a simulated natural ecological environment for a 90-day wild rearing effect verification experiment, during which no food was provided. Survival and growth status were assessed after the experiment.

[0074] Comparative Example 5

[0075] The same number and batch of artificially bred yellow croakers as in Example 2 were used. They were placed in a seedling cultivation vehicle and continuously cultured under artificial conditions for 58 days, during which time only the artificial culture conditions were maintained; this served as a control group. After 58 days of cultivation, 30 yellow croakers were randomly selected, tagged electronically, and transferred to a large net cage in a simulated natural ecological environment experimental sea area. They were not fed for the following 90 days, serving as a synchronous control group for Example 2. The basic ability of these yellow croakers to survive in the natural environment was observed and determined. Their survival and growth status were tested after the experiment.

[0076] Growth rate or weight gain rate = (Wt - W0) / W0 × 100%

[0077] Survival rate SR = Nt / N0 × 100%

[0078] Specific growth rate SGR = (lnWt - lnW0) / t × 100%

[0079] Note: N0 is the initial number of fish tails; Nt is the final number of fish tails; W0 is the initial body length or weight; Wt is the final body length or weight; t is the number of training days.

[0080] Experimental and verification results showed that, after the rewilding method in Example 2, 90% of the yellow croakers exhibited avoidance responses to environmental stimuli such as noise and changing light; 100% of the individuals' resistance to current increased from an average of 0.3 m / s before rewilding to 0.6 m / s after rewilding; and their tolerance to hunger was extended to 4 days. Damage: Among the 200 yellow croakers, 10 showed minor abrasions, accounting for 5%, mainly concentrated on the sides and backs of the fish, presumably caused by friction against the pond walls or other objects during rewilding. No serious lacerations or open wounds were found. Stress-related symptoms: 25 fish showed stress-induced color palering, accounting for 12.5%; 15 fish exhibited loss of appetite, accounting for 7.5%, preliminarily diagnosed as stress enteritis.

[0081] Before the yellow croakers were released into the experimental sea area in large net cages simulating their natural ecological environment, during the domestication pond cultivation stage, the body length and weight of the yellow croakers cultivated in Example 2 and Comparative Example 5 were measured. The specific results are shown in Table 1. Statistical analysis showed that the yellow croakers in Example 2 had a weight gain rate of 13.8% and a length growth rate of 6.7% during the 58-day cultivation period; while in the control group of Comparative Example 5, the weight gain rate and growth rate were as high as 18.4% and 8.4%, respectively, after 58 days of artificial cultivation. From the data comparison, the yellow croakers cultivated using the wild domestication method of this invention had slightly lower weight gain and length growth rates than the control group of Comparative Example 5, but upon closer inspection, the difference was not significant, and the derived specific growth rates were also not significantly different. This result indicates that the wild domestication method of this invention did not have a significant negative impact on the normal growth of the yellow croakers. More importantly, during the process of wild domestication, the yellow croaker endured and gradually adapted to various stresses, which significantly improved its resilience and laid a good foundation for its survival in the natural environment.

[0082] Table 1. Comparison of body length and weight of yellow croaker after 58 days of domestication in earthen ponds and artificial rearing in seedling cultivation vehicles.

[0083]

[0084] After being placed in a large net cage in an experimental sea area simulating a natural ecological environment, the yellow croaker survived alone for 90 days. The experimental data on the effect of domestication and rewilding are shown in Table 2. During the solitary survival stage in the wild, mortality occurred in all comparative groups. After 90 days of natural survival in the large net cage in the experimental sea area, the results showed that the yellow croakers that underwent feeding domestication and environmental adaptation domestication as described in Example 2 had a significantly higher survival rate than the other comparative groups. Specifically, Comparative Example 5, as the control group, was artificially bred and did not undergo domestication and rewilding; its mortality rate was higher than other examples after being placed in the wild. The above results indicate that the domestication scheme combining feeding domestication and environmental adaptation domestication of this invention allows the yellow croaker to withstand various stresses during the domestication and rewilding process, greatly expanding and improving its resilience, thereby increasing its survival rate in the wild. The survival rate reached 93.3% after environmental stress, feeding stress, and disturbance stress, which fully demonstrates that this invention can effectively enhance the survival ability of artificially bred yellow croakers in the wild.

[0085] Table 2 Comparison of growth and survival of yellow croaker in large net cages in the experimental sea area after 90 days

[0086] Group Start exponent End exponent Survival rate SR (%) Example 2 30 28 93.3 Comparative Example 1 30 25 83.3 Comparative Example 2 30 26 86.7 Comparative Example 3 30 25 83.3 Comparative Example 4 30 27 90.0 Comparative Example 5 30 17 56.7

[0087] The above description is only a preferred embodiment of the present invention. It should be noted that for those skilled in the art, several improvements and modifications can be made without departing from the principle of the present invention, and these improvements and modifications should also be considered within the scope of protection of the present invention.

Claims

1. A wild domestication system for yellow croaker, characterized in that, The yellow croaker rewilding and domestication system includes a domestication pond and a circulating water treatment system; the domestication pond is divided into a depression-topped water area, a shallow water area, a steep-slope water area, and a deep water area; the inlet of the circulating water treatment system is set in the depression-topped water area, and the outlet of the circulating water treatment system is set in the deep water area; the domestication pond is also equipped with light, sound, and flow environmental factor devices and monitoring equipment; The light, sound, and flow environmental factor devices include a light source device, an audio device, and a variable frequency submersible pump. The light source device can adjust the light intensity and color temperature. The light source device and the audio device are located above or below the water area of ​​the acclimatization soil pond. The variable frequency submersible pump is located below the water area of ​​the acclimatization soil pond. The light source is a waterproof LED or COB light source; the audio device is used to simulate the low-frequency noise generated by the rotation of a diesel engine and propeller, the high-frequency noise generated by the high-speed rotation of propeller blades, and the noise of a ship's horn; the low-frequency noise has a frequency of 60~200Hz; the high-frequency noise has a frequency of 1~20KHz. The craggy terrain water area is adjacent to the shallow water area and / or the steep slope water area; the steep slope water area extends slopingly from the shallow water area to the deep water area, with a slope of 60 to 80 degrees.

2. The wild rearing system for yellow croaker according to claim 1, characterized in that, The shallow water area accounts for 30% to 50% of the area of ​​the acclimatization pond; the deep water area accounts for 25% to 35% of the area of ​​the acclimatization pond; the steep slope water area accounts for 5% to 15% of the area of ​​the acclimatization pond; and the pitted and uneven terrain water area accounts for 10% to 30% of the area of ​​the acclimatization pond.

3. The wild domestication system for yellow croaker according to claim 1, characterized in that, The shallow water area has an average depth of 1-2m; the deep water area has an average depth of 2.5-3.5m; and the undulating terrain area has an average depth of 1.5-2.0m.

4. The wild domestication system for yellow croaker according to claim 1, characterized in that, The circulating water treatment system includes a mechanical granular drum filter, an aeration tank, an upflow anaerobic tower, and a variable frequency submersible pump connected in sequence by pipelines. The aeration tank is equipped with an air flotation machine.

5. A method for domesticating yellow croaker based on the wild domestication system according to any one of claims 1 to 4, characterized in that, The temperature and salinity of the water in the breeding pond are adjusted to suit the breeding of yellow croaker. The yellow croaker are then put into the pond for feeding and environmental adaptation training. The feeding training is intermittent fasting training, with different types of food being fed and the amount of food being gradually increased and rotated; the environmental adaptation training includes resistance to flow stress training, resistance to noise stress training, resistance to light stress training, and enhanced avoidance training. The intermittent fasting training adopts a cyclical pattern of "feeding once a day + fasting for 4 days". Each time, one type of food is fed, and the amount of food is increased in a gradient of 10%, 40%, 70%, 100%, and 130% of the fish's body weight. The anti-current stress training involves gradually increasing the water flow rate from 0.01 m / s to 1 m / s, and maintaining the flow rate for 30 to 60 minutes when the yellow croaker reaches a critical equilibrium position in its countercurrent movement. The noise stress resistance training involves playing ship noise; The anti-light stress training uses instantaneous strong light, then gradually dims until the original light intensity is restored, or an instantaneous cold light to warm light mode. The avoidance training is a combination of noise stress training followed by mechanical contact, or noise stress training or light stress training combined with flow stress training.

6. The method according to claim 5, characterized in that, The breeding ponds also contain 5% to 15% of yellow croaker and spotted bluefish.

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