High-yielding aquaculture technology of bay scallop

1. Mesh basket production must be matched and properly calculated based on 100,000 grains per mu. Each cage needs 400mm diameter (preferably 350mm), and 8-10 layers of cages (near 15-20mm). . At the same time, it is necessary to raise 3 mm and 5 mm small seedlings for raising cages, 30 and 20 respectively. For raising seedlings and sparse seedlings. Whether it is cages or cages for sewing, the plastic trays with a spacing of (100 mm) must be kept parallel to each other, and no skewing of one layer is allowed. Because as long as there is a layer of tilt will cause uneven distribution of scallops in all layers of the cage, stacked to the side, affecting the normal feeding and growth of scallops. In addition, when sewing net cages, regardless of whether the various layers or sutures must be sewn together with a buckle, do not buckle or buckle, to prevent the "string seedlings" and "run seedlings" phenomenon.
2, to use "early, strong, large" seed bay scallops different from other scallops. It must be cultivated in the same year, and it is only meaningful to achieve the full harvest of the merchandise shellfish. This is because the life cycle of the bay scallop is only one year. Therefore, the cultured bay scallops should be raised early (controlling the temperature every year from March to April). Should use as early as possible, large seedlings and strong seedlings. As the progress of nursery is not smooth, there will always be a certain amount of late seedlings and weak seedlings every year. It must not be to purchase late seedlings in order to save money. Because the late seedlings will often delay the rapid growth of scallops, seriously affect the growth effect. For the bay scallop breeding seedlings, it is best to use commercial seedlings with a shell height of 5 mm before mid-June. The time required for the development of the cages should be as early as possible, as long as the seedlings reach the specifications for cultivation.
3, to timely sparse seedlings, down the cage because the bay scallops from the seed cultivation to Chengbei harvest, only more than six months time, in fact, only to develop more than four months. Therefore, after the purchase of small seedlings, it is necessary to strengthen the management of the sea. When the shell height reaches 5mm, it must be screened into the holding cage (3-5mm in size). When the shell height reaches 20mm, it is necessary to grasp and pour into a breeding cage (eye 20mm) for cultivation. Must not wait until the seedling height reaches 5mm and then enter the holding cage. It is even more impossible to wait for the height of the shell shoot shell in the holding cage to reach 20mm and then raise into a cage. Instead, they must be screened in stages and treated in batches. 20-30% of the shellfish in the holding cage should reach 20mm in shell height and the seedlings should be screened into a cage. Generally after 2-3 screenings, the seedlings can almost enter into the growing cages, which can not only promote the rapid growth of the shellfish but also increase the survival rate of the shellfish seedlings.
4. The seedling density should be divided into seedlings at reasonable density, which refers to the number of seedlings per layer per cage. A reasonable density of seedlings is one of the important technical aspects of high-yield and high-efficiency bay scallops. Some production units think that the individuals in the bay scallops are smaller than those in the scallops and scallops. Therefore, artificially increasing the density of seedlings in each layer in the growing process is very wrong. Because bay scallops are gluttonous and fast-growing shellfish, they grow fast. One of the most important reasons is that it has a large amount of filtered water and a large amount of food. If artificially increasing the cultivated density of 30/layer is more than 40/layers, the density of yield increases by 18.2%, and the output value increases by 36.7%. Therefore, the stocking density of the bay scallop should be 30/layer.
5, to increase the stability of cages Bay scallops fully developed, the attachment is very weak. In stormy weather, especially in sea areas with shallow water depths, the net cages are bumpy along the waves and the scallops collide with each other, which not only affects the normal feeding of scallops, but also causes the shell edges to wear out, which seriously affects their survival rate and growth. Therefore, enhancing the stability of cages in water is an important technical measure for increasing production. The current effective methods are: First, increase the falling stone, that is, each of the holding cage and the raising cage should be tied with a 1-1.5 kg stone; second, the use of multi-layer cages (8-10 Layer)) eliminate small cages (layers 5-7); third, float ropes can be used to control the water layer around 100cm; fourthly, increase the aquaculture water layer, especially the stormy sea area, to the typhoon season water layer. Try to put it below 3m.
6. The scientific management of the bay scallops is weak and has poor adhesion. In addition, the bay scallops are relatively smooth and have a short growing period. The cages are not easily attached to the floating mud, and there is no need to wash them frequently. Frequently washing only artificially destroys it and makes it more stable. Production practices have proven that over-washing net cages will result in reduced production of bay scallops. Therefore, the management of bay scallops is relatively simple. It is always necessary to check whether there are drifts, kinks, drop stones, etc., especially after strong winds must be checked and problems must be solved in time. In addition, before the onset of the typhoon season and the flood season, we should pay close attention to the general deepening of the aquaculture water layer (below 3 m) to ensure safe and normal growth of scallops.