Method for realizing efficient conservation of Lutraria philippinarum families by using artificial fish reefs in marine ranch

Abstract

The invention discloses a method for realizing efficient conservation of a Lutraria philippinarum family by utilizing artificial fish reefs in a marine ranch. The method comprises the following steps: (1) selecting the artificial fish reefs in a site and the ranch; (2) reef body identification; (3) putting specification and density; (4) throwing seedlings; (5) breeding management; (6) establishing a high-quality family group; and (7) catching and selecting the parents of the next level. According to the method, through family construction, selection of artificial fish reefs of a marine ranch, isolated breeding of families in the artificial fish reefs, establishment of high-quality family groups, collection and selection of next-level parents, synchronous backup of molecular marker information and a phenotype database, informatization archiving of the selection process is completed, and a complete marine family management and breeding mode is formed; and a germplasm foundation is laid for expanding propagation of improved varieties of the next generation.

Description

Technical Field

[0001] This invention relates to the field of development and utilization technology of artificial reefs in marine ranching for breeding, and more specifically to a method for achieving efficient conservation of otter clam families using artificial reefs in marine ranching. Background Technology

[0002] The otter clam (Lutraria), commonly known as the "elephant nose snail," is a warm-water mollusk distributed in tropical and subtropical seas. Its habitat ranges from 12-32°C in water with salinity of 11.50-33.00, pH of 8.2-8.4, and transparency of 4-7 meters. It primarily feeds on benthic diatoms and organic detritus, exhibits burrowing behavior, and migrates short distances. Under suitable conditions, the otter clam's migration rate is low; even with a 50cm high physical enclosure, its escape rate is ≤1%. Otter clams are typically selected from individuals aged 18-24 months with superior traits as parents. Breeding new mollusks usually requires 8-15 years to obtain stable, nationally recognized new varieties. Most mollusks (such as scallops and hard clams) reach sexual maturity in 2 years; therefore, conventional breeding follows a "two-year generation selection" approach, requiring approximately 10 years to obtain a stable new variety. However, through methods such as iterative breeding, the generation time can be shortened. However, the marine environment is complex, and once the offspring are mixed, the breeding cycle will be continuously extended. Therefore, it is especially important to protect each offspring during the breeding process.

[0003] During the summer, the Beibu Gulf is affected by the monsoon climate, with large southwest waves. During the juvenile stage of the otter clam, the burrowing sand is shallow, and it is easily stirred out of the cultivation or breeding site by the southwest waves. At this stage, the facility-based breeding baskets or breeding net cages are very easy to be overturned or buried. At present, the aquaculture conservation work urgently needs to be completed with a more robust feeding system.

[0004] Artificial reefs are man-made seabed deposits designed to attract and inhabit fish, resulting in a significant fish-attracting effect. They extend the time fish spend in the reef area, expanding fishing grounds and promoting fish populations. Artificial reefs can be categorized by shape, including cubes, polyhedrons, cones, cylinders, semicircles, and various large assembled reefs. They can also be classified by construction purpose, such as catch-oriented (the most common), conservation, cultivation, induction, and shallow-sea propagation reefs. Therefore, while expanding fishing grounds, the open sections of artificial reefs can be used to conserve bottom-seeded shellfish. Interventional management of the reef's interior and the formation of a physical barrier around the external organisms achieve the desired effect of isolated conservation.

[0005] Therefore, based on the physiology and living habits of the otter clam, and combined with the existing artificial reef layout of the ranch, as well as the characteristics and shape of the artificial reef itself, an isolated breeding model was formed to isolate and cultivate seedlings of multiple otter clam families. This proposed an efficient conservation method for otter clam families in marine ranches, which solves the shortcomings of difficult and costly installation of equipment in multiple family areas, as well as the mixing of families due to equipment damage. This is of great significance for the development of non-migratory bottom-seeded mollusks. Summary of the Invention

[0006] In view of this, the present invention provides a method for efficient conservation of otter clam families using artificial reefs in marine ranches. This method addresses the shortcomings of setting up conservation facilities in marine areas, such as difficulties in installation, high investment costs, and family mixing due to equipment damage, ensuring the successful completion of breeding programs through improved equipment and facilities.

[0007] To achieve the above objectives, the present invention adopts the following technical solution: A method for efficient conservation of otter clam families using artificial reefs in marine ranches includes the following steps: (1) Site and artificial reef selection for ranch Site selection: Select an open sea area that is not an inner bay, with a sandy bottom, a sand content greater than 70%, a seawater salinity of 25-33, a pH of 7.2-8.5, a dissolved oxygen of 6.9-8.2 mg / L, stable water quality physicochemical conditions, and a distance of more than 5 nautical miles from inland runoff, and a water depth of 8-15m. Selection of artificial reefs: Artificial reefs used for stocking and breeding shellfish inside the reef must have sufficient apparent volume. The bottom of the artificial reef should be hollow and in contact with the artificial pasture. The reef should be 2m x 2m, with a hollow structure without crossbeams at the top and bottom. The reefs should be arranged neatly. A 40cm-50cm barrier should be set at the lower middle part of the artificial reef that is in contact with the bottom to achieve physical isolation. Under the premise of physical isolation, seedlings of another family should be stocked inside the reef after one row or column of artificial reefs. (2) Reef markings The reef markers are made of corrosion-resistant materials, with clear and unique numbers. They are linked to Geographic Information System (GIS) positioning data to achieve precise spatial management of each reef. The markers are fixed in conspicuous positions on the top and sides of the reef. The underwater QR code is linked to the reef marker in the same area to facilitate diving inspection and remote monitoring. All reef marker information is synchronously entered into the ranch management database. Combined with the underwater QR code, it is linked to the release time, quantity and genetic background of the corresponding family seedlings to ensure that the entire conservation process is traceable and to provide information support for the efficient isolation and management of otter clam families. (3) Placement specifications and density For the selected offspring, choose individuals that are uniform in size, undamaged, and have strong sand-buried ability. The size of the seedlings to be released should be 2.0g-4.0g / each. Seedlings smaller than 2.0g can be cultivated to the required size before being released. (4) Seedlings Before releasing the seedlings, drive away and clear away harmful organisms from the sand surface and buried in the sand with a toothed rake. After releasing the seedlings, set up a 5cm high net covering the seedling reef.

[0008] Seedlings should be introduced in designated areas according to family lineage, and evenly distributed throughout the reef. Mechanical damage should be avoided during introduction, allowing the seedlings to naturally settle in the sand. Introduce fewer or no seedlings in the inner edge areas of the reef. The seedling density should be 15-30 seedlings / m². 2 .

[0009] (5) Aquaculture management Immediately after the seedlings are planted, the underwater monitoring system is activated. Combined with regular underwater patrols, the distribution of seedlings, the dynamics of sand burial, and the integrity of the enclosure are monitored to prevent escape or cross-contamination.

[0010] After stocking, the growth status, survival rate, and substrate changes of each family are monitored regularly, and management strategies are adjusted based on hydrological data. Environmental parameters and biological behavior data are recorded in real time. A monthly underwater inspection is conducted, focusing on verifying the sealing of the enclosure and the integrity of the markings, and any damaged parts are replaced promptly. On the 15th day after stocking, the first family survival rate is calculated, and growth data is recorded by sampling. Based on the sampling results, when the average individual weight is ≥15g, graded thinning is initiated, reducing the density to 8-10 individuals / m². 2 This optimizes space utilization, maintains the rapid growth trend of individual family members, and facilitates the selection of the best parent lines for later use in the family line.

[0011] (6) Establishment of high-quality family groups Once the average weight of individuals reached ≥30g, a family genetic purity assessment was initiated. Tissue samples were collected for molecular marker testing to ensure no gene exchange occurred during isolated rearing. Simultaneously, a comprehensive evaluation of growth traits was conducted to select high-quality families with rapid growth and strong resistance, serving as the basis for the next generation of breeding. Special preservation areas were established for outstanding families to extend their rearing period and accumulate more phenotypic data. All operations were performed according to standardized procedures and incorporated into an information management system, achieving a data loop from seedling release to parent selection, providing continuous support for the breeding of superior Otter Clams.

[0012] (7) Collection and selection of the next level of parent lines Sampling was conducted on high-quality family breeding areas, and individuals whose body weight exceeded the family average by more than 10% were selected as candidate parents. After phenotypic evaluation of individual Otter Clams, individuals with strong vitality and well-developed gonads were selected and transferred to an indoor maturation system to avoid inbreeding depression. Molecular marker information and phenotypic databases were backed up simultaneously, and the selection process was completed through information-based archiving, laying the germplasm foundation for the propagation of superior breeds in the next generation.

[0013] Strict single-family isolation procedures were implemented during the harvesting process to prevent cross-contamination. Harvesting was conducted using diving methods, and tools were disinfected and assigned to specific families to ensure traceability of genetic background.

[0014] The enclosure material uses a corrosion-resistant polyethylene mesh frame structure with a pore size controlled between 0.5-1.2cm to ensure smooth water flow and prevent seedlings from escaping. Preferably, the distance between the reefs is maintained at 3-5m to reduce environmental competition and improve management efficiency; Preferably, the underwater QR code must be waterproofed and fixed in a conspicuous position on the reef to ensure readability and durability. During harvesting, the tag is scanned using a handheld terminal to verify the pedigree number and growth data in real time, ensuring the accuracy of the parentage. The entire operation is recorded in the traceability system, enabling two-way tracking of germplasm information.

[0015] Preferably, the hostile organisms refer to carnivorous fish, crabs, etc.

[0016] Preferably, the cover net refers to an 8-10 mesh polyethylene cover net, which reduces the impact of harmful organisms on the isolation and protection of the clam seedlings within 30-45 days after seedling introduction. The cover net is removed 30 days after seedling introduction when the seedlings have grown stably and reached a size of 5g / seedling.

[0017] Preferably, the underwater monitoring system includes underwater imaging equipment and environmental sensors. Each family is equipped with 1-2 high-definition cameras. The system allows real-time viewing of the figure-eight pattern left by the slugs' siphons after burrowing into the sand, along with their movement, via a cloud platform. An environmental sensor system is installed in the central area of ​​the marine ranch conservation zone, monitoring temperature, salinity, turbidity, dissolved oxygen, and pH. The environmental sensor automatically collects data every two hours, and the encrypted data is uploaded to the cloud platform in real time. As can be seen from the above technical solution, compared with the prior art, the present invention has the following technical effects: This invention establishes a complete marine family management model through family construction, selection of artificial reefs for marine ranching, isolation and cultivation of families within artificial reefs, establishment of high-quality family populations, collection and selection of next-level parent lines, simultaneous backup of molecular marker information and phenotypic databases, and information-based archiving of the selection process. This lays the germplasm foundation for the propagation of superior varieties in the next generation.

[0018] This invention has significant practical implications and application value for the breeding of superior varieties of otter clams. This method cleverly utilizes the physical barrier characteristics and fish-attracting effect of artificial reefs in marine ranches, combined with refined aquaculture management and information technology, effectively solving problems such as easily damaged equipment, mixed lineages, and prolonged breeding cycles in traditional marine family conservation.

[0019] This invention ensures the stable transmission of genetic purity and superior traits in each breeding generation through strict site selection, reef marking, scientific release specifications and density control, and meticulous aquaculture management. This model, which deeply integrates artificial reefs with Otter Clam family conservation technology, opens up new avenues for the multifunctional utilization of marine ranches. It also provides a referable technical paradigm for the efficient breeding of other non-migratory benthic mollusks, and has a profound impact on promoting the improvement of breeds and the sustainable development of my country's marine aquaculture industry.

[0020] It has a great promoting effect on the industrialization of artificial aquaculture, has creative and high practical value, and is of great significance for protecting and developing marine resources, boosting the economy, enriching the structure of marine aquaculture species, and implementing the sustainable development strategy. Attached Figure Description

[0021] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on the provided drawings without creative effort.

[0022] Figure 1 This is a schematic diagram of an artificial reef structure. Figure 2 This is a schematic diagram showing the arrangement of protected and non-protected reefs. Detailed Implementation

[0023] The technical solutions in the embodiments of the present invention will be clearly and completely described below. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0024] Example 1 Breeding steps: (1) Site and ranch artificial reef Within the artificial reef site of the Beihai National Marine Ranch, the bottom is sandy with an average sand content of over 70%. The seawater salinity is 25-33, pH 7.2-8.5, and dissolved oxygen 6.9-8.2 mg / L throughout the year. The water quality and physicochemical conditions are stable, and the area is far from the runoff-affected zone with a water depth of 12m. The artificial reef measures 2m × 2m × 2m. A concrete horizontal pillar is positioned 30cm from the bottom of the reef, and a 20cm high netting is placed near the pillar. One row of each family is stocked, with one row spaced between each family without stocking any other family. A total of 16 families are stocked. The stocking quantity and parentage source for each family are from Beihai and Zhanjiang populations that have been cultured for 14 months, as shown in Table 1 below. Table 1

[0025] (2) Reef marking Raw plastic labels and cable ties are used to create reef markers. Each label has a clear and unique number and is uniformly and securely affixed to a prominent location on the same side of the reef. A QR code is also created for each family lineage and affixed to the same side of the reef along with the label, facilitating underwater inspections and remote probe monitoring. All label information is simultaneously entered into the ranch management database, linking it to the release time, quantity, and genetic background of the corresponding family's seedlings. This ensures full traceability of the conservation process and provides information support for the efficient isolation and management of otter clam families. (3) Placement specifications and density For the selected offspring, choose individuals that are uniform in size, undamaged, and have strong sand-buried ability. The size of the seedlings to be released should be 2.0g-4.0g / each. Smaller seedlings can be cultivated to the required size before being released. (4) Seedlings Before planting the seedlings, use a rake to clear away harmful organisms from the sand surface and burrowing in the sand. After planting the seedlings, set up a 5cm high net.

[0026] Seedlings were distributed evenly throughout the reef, categorized by family lineage. Mechanical damage was avoided during distribution, allowing the seedlings to naturally burrow into the sand. Minimize or avoid seeding in the inner edge areas of the reef. The seeding density was 15 seedlings / m². 2 Individuals that do not dive into the sand within 2 hours should be promptly retrieved and released into other sea areas as regular seedlings.

[0027] The distribution of each family line is shown in Table 2: Table 2

[0028] (5) Aquaculture Management Immediately after the seedlings are planted, the underwater monitoring system is activated. Combined with regular underwater patrols, the distribution of seedlings, the dynamics of sand burial, and the integrity of the enclosure are monitored to prevent escape or cross-contamination.

[0029] After stocking, the growth status, survival rate, and substrate changes of each family are monitored regularly, and management strategies are adjusted based on hydrological data. Environmental parameters and biological behavior data are recorded in real time. Underwater inspections are conducted monthly, focusing on checking the sealing of the enclosure and the integrity of the markings, and damaged parts are replaced promptly. On the 15th day after stocking, the first family survival rate is counted, and growth data is sampled and recorded. Based on the sampling results, when the average weight of individuals reaches 15.38g, graded thinning is initiated, reducing the density to 10 individuals / m², optimizing space utilization, maintaining the rapid growth trend of individual family members, and facilitating the selection of superior parent stock for later use.

[0030] (6) Establishment of high-quality family groups Once the average weight of the sampled individuals reached 30.02g, a family genetic purity assessment was initiated. Simultaneously, a comprehensive evaluation of growth traits was conducted to screen for high-quality families exhibiting rapid growth and strong resistance, serving as the basis for the next generation of breeding. Special preservation areas were established for outstanding families to extend their rearing period and accumulate more phenotypic data. All operations were performed according to standardized procedures and incorporated into an information management system, achieving a closed-loop data system from seedling release to parent selection, providing continuous support for the breeding of superior Otter Clams.

[0031] Three hundred individuals from each family were selected as high-quality family groups and separately placed into new artificial reefs for preservation, at a density of 10 individuals / m². 2 .

[0032] The following table shows the details of each high-quality family group after the selection: Table 3

[0033] (5) Harvesting of the next-level parent lines and further selection The culture period was 16 months in the artificial reef of the marine ranch. All families were harvested and statistically analyzed. The survival rate, average weight of the family population, and the body weight of the largest and smallest individuals were recorded for each family. The results are shown in Table 4 below. Table 4

[0034] Individuals whose body weight exceeds the family average by more than 10% are selected as candidate parents. After phenotypic evaluation of individual Ospreys, individuals with strong vitality and well-developed gonads are selected and transferred to an indoor maturation system to avoid inbreeding depression. Molecular marker information and phenotypic databases are backed up simultaneously, and the selection process is archived digitally to lay the germplasm foundation for the propagation of superior varieties in the next generation.

[0035] The various embodiments in this specification are described in a progressive manner, with each embodiment focusing on its differences from other embodiments. Similar or identical parts between embodiments can be referred to interchangeably. For the apparatus disclosed in the embodiments, since they correspond to the methods disclosed in the embodiments, the description is relatively simple; relevant parts can be referred to the method section.

[0036] The above description of the disclosed embodiments enables those skilled in the art to make or use the invention. Various modifications to these embodiments will be readily apparent to those skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of the invention. Therefore, the invention is not to be limited to the embodiments shown herein, but is to be accorded the widest scope consistent with the principles and novel features disclosed herein.

Claims

1. A method for efficient conservation of otter clam families using artificial reefs in marine ranches, characterized in that, Includes the following steps: (1) Site and artificial reef selection for ranch Site selection: Select an open sea area that is not an inner bay, with a sandy bottom, a sand content greater than 70%, a seawater salinity of 25-33, a pH of 7.2-8.5, a dissolved oxygen of 6.9-8.2 mg / L, stable water quality physicochemical conditions, and a distance of more than 5 nautical miles from inland runoff, and a water depth of 8-15m. Selection of artificial reefs: The artificial reef body is hollow at the bottom and contacts the artificial pasture. The reef is 2m2m×2m, with a hollow structure without crossbeams at the top and bottom. The reef bodies are arranged neatly. A 40cm-50cm barrier is sealed or can be stably suspended at the middle and lower part of the reef body to achieve physical isolation. Under the premise of physical isolation, seedlings of another family are released into the reef body after one row or one column of artificial reefs. (2) Reef markings The reef markers are made of corrosion-resistant materials, with clear and unique numbers. They are linked to geographic information system positioning data and fixed to the top and sides of the reef. The underwater QR code is also linked to the reef marker in the same area. All reef marker information is synchronously entered into the ranch management database. Combined with the underwater QR code, the release time, quantity, and genetic background of the corresponding family seedlings are associated to ensure that the entire conservation process is traceable. (3) Placement specifications and density Select offspring individuals that are uniform in size, undamaged, and have strong sand-buried abilities. Raise them to a size of 2.0g-4.0g each before releasing them as seedlings. Seedlings smaller than 2.0g should be cultivated to the required size before being released. (4) Seedlings Before releasing the seedlings, drive away and clear away the harmful organisms on the sand surface and buried in the sand with a toothed rake. After releasing the seedlings, set up a 5cm high cover net inside the seedling reef and fix it inside the seedling reef. Seedlings should be introduced in designated areas according to family lineage, and evenly distributed throughout the reef. Mechanical damage should be avoided during introduction, allowing the seedlings to naturally settle in the sand. Introduce fewer or no seedlings in the inner edge areas of the reef. The seedling density should be 15-30 seedlings / m². 2 ; (5) Aquaculture management Immediately after the seedlings are planted, the underwater monitoring system is activated. Combined with regular underwater patrols, the distribution of seedlings, the dynamics of sand burial, and the integrity of the enclosure are monitored to prevent escape or cross-contamination. After seedling introduction, the growth status, survival rate and changes in the substrate of each family are monitored regularly. Management strategies are adjusted based on hydrological data, and environmental parameters and biological behavior data are recorded in real time. Underwater inspections are carried out once a month to check the sealing of the enclosure and the integrity of the markings, and damaged parts are replaced in a timely manner. On the 15th day after seedling introduction, the first family survival rate was counted and growth data were recorded by sampling. Based on the sampling results, when the average weight of individuals was ≥15g, graded thinning was initiated, and the density was reduced to 8-10 individuals / m². 2 ; (6) Establishment of high-quality family groups Once the average weight of individuals reaches ≥30g, a family genetic purity assessment is initiated. Tissue samples are collected for molecular marker detection to ensure that no gene exchange occurs during isolated breeding. Simultaneously, a comprehensive evaluation of growth traits is conducted to screen out high-quality family groups with fast growth and strong resistance, which will serve as the basis for the next generation of breeding. Special preservation areas are established for families with outstanding performance, and their breeding cycle is extended to accumulate more phenotypic data. All operations are carried out according to standardized procedures and incorporated into an information management system to achieve a data loop from seedling release to parent selection, providing continuous support for the breeding of superior Otter Clams. (7) Collection and selection of the next level of parent lines Sampling was conducted on high-quality family breeding areas. Individuals whose body weight exceeded the average body weight of the family by more than 10% were selected as candidate parents. After phenotypic evaluation of the individual clam, individuals with strong vitality and full gonadal development were selected and transferred to the indoor maturation system to avoid inbreeding depression. Synchronously back up molecular marker information and phenotypic databases, complete the information-based archiving of the selection process, and lay the germplasm foundation for the propagation of next-generation improved varieties; Strict single-family isolation procedures were implemented during the harvesting process to prevent cross-contamination. Harvesting was conducted using diving methods, and tools were disinfected and assigned to specific families to ensure traceability of genetic background.

2. The method for efficient conservation of otter clam families using artificial reefs in marine ranches according to claim 1, characterized in that, The fencing is made of polyethylene mesh with a mesh size of 0.5-1.2cm.

3. The method for efficient conservation of otter clam families using artificial reefs in marine ranches according to claim 1, characterized in that, The spacing between the artificial reefs is 3-5m.

4. The method for efficient conservation of otter clam families using artificial reefs in marine ranches according to claim 1, characterized in that, The underwater QR code is waterproofed and fixed to the reef.

5. A method for efficient conservation of otter clam families using artificial reefs in marine ranches, as described in claim 1, is characterized in that... The hostile organisms are carnivorous fish and crabs.

6. The method for efficient conservation of otter clam families using artificial reefs in marine ranches according to claim 1, characterized in that, In step (7), the tags are scanned by handheld terminals during harvesting to verify the family number and growth data in real time, ensuring that the parent source is accurate. The entire operation is recorded in the traceability system to achieve two-way tracking of germplasm information.

7. A method for efficient conservation of otter clam families using artificial reefs in marine ranches, as described in claim 1, is characterized in that... The cover net is an 8-10 mesh polyethylene cover net, which is removed 30 days after the seedlings are planted and their growth is stable and their size reaches 5g / seedling.

8. A method for efficient conservation of otter clam families using artificial reefs in marine ranches, as described in claim 1, is characterized in that... The underwater monitoring system includes underwater imaging equipment and environmental sensors. Each family is equipped with 1-2 high-definition cameras. The system allows real-time viewing of the figure-eight pattern left by the slug siphon after burrowing in the sand, as well as images of their movement, captured by each camera on a cloud platform. A set of environmental sensors is installed in the central area of ​​the marine ranch conservation area, including temperature, salinity, turbidity, dissolved oxygen, and pH. The environmental sensors automatically collect data every two hours, and the data is encrypted and uploaded to the cloud platform in real time.

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