Silverfish Transplantation Proliferation and Fishing Technology (I)
2018-06-05 19:00:18
Silverbait is one of the major aquatic products for export in China. Although the individuals are small, the whole fish can be eaten. It is rich in nutrients, delicious and tasty, and convenient to cook. It is welcomed by consumers at home and abroad.
The life of whitebait is about 1 year. It is mainly distributed in the offshore and inland waters of Southeast Asian countries. It has strong reproduction ability and rapid growth. It does not need feeding and fishing is convenient. Since the success of the silverfish migration in Dianchi Lake in 1979 and the rapid start of large-scale production, many lakes and reservoirs across the country have begun the colonization of whitebait and have a good economic effect. The whitebait has become an excellent breeding and breeding facility for inland waters in China. Variety.
First, put the technology (a) Placement of the selection of the site as much as possible selected at a distance from the shore, water depth of about 2 meters, with hard sediment or gravel sediments, insects and other small bait creatures rich Kuwan. At the same time, it is necessary to select several delivery sites for multiple delivery at the same time to avoid failure due to improper delivery of one point.
(II) Feeding method of fish eggs When the fertilized eggs reach their destination, put the nylon bag with fertilized eggs into the water first, and after the water temperature in the bag is basically the same as the water temperature of the reservoir water (temperature difference is less than 3°C), fertilize the eggs slowly. Slowly and evenly dispersed into the water, each input point should have a certain area and range. In the north, more ice eyes should be made and fish eggs should be thrown into the water directly from the ice eyes. The action of egg-laying is quick and avoid freezing eggs. If the bottom of soft mud is thick, open a few ice eyes of 1m square on the ice, first sink a 50cm50cm10cm self-made gauze (sieve) cage into the water surface, then drop the fertilized eggs and slowly The cage sinks to a depth of 2 meters and is secured with plastic floats.
(3) Management of ice-free reservoirs after delivery of fertilized eggs After the release of fish eggs, the protection of the egg-laying farm should be watched for one month. It is mainly forbidden to use nets and underwater activities such as pulling nets, fishing, and fish fry in this area. Icing reservoirs, especially reservoirs that use cages to deliver fish eggs, should be patrolled frequently at the beginning of a few days to prevent cages from being raised on the surface of the water and causing damage to fish eggs. After half a month, break the ice and lift the cage up to the surface of the water to brush off the attachments on the cage. At the same time, some eggs can be sucked out to check the development and survival rate of the embryos. Slowly sink the box into the water. The eggs were incubated at 1.5～5°C in the low temperature environment under ice, the incubation time was 63-65 days, and the water temperature was 6-7°C. Incubation time is about 30 days when the water temperature is 2 to 10°C during the incubation period. At the temperature of 11～16.5°C, the number of days of filming is about 6 days (refers to the paste of whitebait).
(IV) Transplantation Density and Repeated Transplantation Large- and medium-sized reservoirs (lakes) Generally, 150 to 800 fertilized eggs per 0.067 hectare are transplanted. After one transplant, the transplant should be repeated twice in the second year to increase the population and enhance the survival of the population. In addition, according to the biological characteristics and living habits of the whitebait, adult transplantation (difficulty) can also be performed during the low temperature period. The time is generally 11 to 12 months, the water temperature is 10 to 15°C, the ratio of male to female is 3:1, and transportation is available. The bag is oxygenated and sealed, 50 pieces/bag, and the whole process cannot touch the fish by hand.
Second, the main measures for the protection and proliferation of whitebait resources (A) to protect the natural ecological environment of water is not destroyed, but also through the scientific ratio of reasonable fertilization, maintaining the balance of nutrients in the water body, in order to improve the primary water productivity.
(2) Adjust the species structure of farmed fish, reduce or stop the amount of squid feeding properly, ensure the supply of whitebait food, and reduce the competition for food objects.
(3) Take effective measures to timely and aggressively capture ferocious fish, especially carnivorous fish, to protect the population and quantity of whitebait fish and reduce predators.
(D) According to the amount of silverfish resources and growth, reproduction rules, each year through the test to determine the fishing gear, fishing time and intensity.
(e) Constantly explore and study the status of the resources that form the population and the reasons for its impact on resource changes, adjust the time and intensity of operations, determine the proportion of retained resources and the amount of resources that can be captured.
(6) Establish a production management system, strengthen the management of fishery administration, demarcate prohibited fishing areas and closed fishing seasons, protect spawning sites and spawning broodstock. (to be continued)
The life of whitebait is about 1 year. It is mainly distributed in the offshore and inland waters of Southeast Asian countries. It has strong reproduction ability and rapid growth. It does not need feeding and fishing is convenient. Since the success of the silverfish migration in Dianchi Lake in 1979 and the rapid start of large-scale production, many lakes and reservoirs across the country have begun the colonization of whitebait and have a good economic effect. The whitebait has become an excellent breeding and breeding facility for inland waters in China. Variety.
First, put the technology (a) Placement of the selection of the site as much as possible selected at a distance from the shore, water depth of about 2 meters, with hard sediment or gravel sediments, insects and other small bait creatures rich Kuwan. At the same time, it is necessary to select several delivery sites for multiple delivery at the same time to avoid failure due to improper delivery of one point.
(II) Feeding method of fish eggs When the fertilized eggs reach their destination, put the nylon bag with fertilized eggs into the water first, and after the water temperature in the bag is basically the same as the water temperature of the reservoir water (temperature difference is less than 3°C), fertilize the eggs slowly. Slowly and evenly dispersed into the water, each input point should have a certain area and range. In the north, more ice eyes should be made and fish eggs should be thrown into the water directly from the ice eyes. The action of egg-laying is quick and avoid freezing eggs. If the bottom of soft mud is thick, open a few ice eyes of 1m square on the ice, first sink a 50cm50cm10cm self-made gauze (sieve) cage into the water surface, then drop the fertilized eggs and slowly The cage sinks to a depth of 2 meters and is secured with plastic floats.
(3) Management of ice-free reservoirs after delivery of fertilized eggs After the release of fish eggs, the protection of the egg-laying farm should be watched for one month. It is mainly forbidden to use nets and underwater activities such as pulling nets, fishing, and fish fry in this area. Icing reservoirs, especially reservoirs that use cages to deliver fish eggs, should be patrolled frequently at the beginning of a few days to prevent cages from being raised on the surface of the water and causing damage to fish eggs. After half a month, break the ice and lift the cage up to the surface of the water to brush off the attachments on the cage. At the same time, some eggs can be sucked out to check the development and survival rate of the embryos. Slowly sink the box into the water. The eggs were incubated at 1.5～5°C in the low temperature environment under ice, the incubation time was 63-65 days, and the water temperature was 6-7°C. Incubation time is about 30 days when the water temperature is 2 to 10°C during the incubation period. At the temperature of 11～16.5°C, the number of days of filming is about 6 days (refers to the paste of whitebait).
(IV) Transplantation Density and Repeated Transplantation Large- and medium-sized reservoirs (lakes) Generally, 150 to 800 fertilized eggs per 0.067 hectare are transplanted. After one transplant, the transplant should be repeated twice in the second year to increase the population and enhance the survival of the population. In addition, according to the biological characteristics and living habits of the whitebait, adult transplantation (difficulty) can also be performed during the low temperature period. The time is generally 11 to 12 months, the water temperature is 10 to 15°C, the ratio of male to female is 3:1, and transportation is available. The bag is oxygenated and sealed, 50 pieces/bag, and the whole process cannot touch the fish by hand.
Second, the main measures for the protection and proliferation of whitebait resources (A) to protect the natural ecological environment of water is not destroyed, but also through the scientific ratio of reasonable fertilization, maintaining the balance of nutrients in the water body, in order to improve the primary water productivity.
(2) Adjust the species structure of farmed fish, reduce or stop the amount of squid feeding properly, ensure the supply of whitebait food, and reduce the competition for food objects.
(3) Take effective measures to timely and aggressively capture ferocious fish, especially carnivorous fish, to protect the population and quantity of whitebait fish and reduce predators.
(D) According to the amount of silverfish resources and growth, reproduction rules, each year through the test to determine the fishing gear, fishing time and intensity.
(e) Constantly explore and study the status of the resources that form the population and the reasons for its impact on resource changes, adjust the time and intensity of operations, determine the proportion of retained resources and the amount of resources that can be captured.
(6) Establish a production management system, strengthen the management of fishery administration, demarcate prohibited fishing areas and closed fishing seasons, protect spawning sites and spawning broodstock. (to be continued)