The benefit of oyster culture in tidal flat is good. Key points of high-yield vertical culture of oyster.

Oysters, commonly known as "oyster yellow" and "oysters", are white and tender, nutritious and delicious, known as "sea milk". Now the oyster culture technology is introduced as follows for reference.

Management of oyster culture

First, select the sea area of collecting seedlings:

Oyster seedlings used for breeding everywhere are natural seedlings in the ocean. To collect oyster seedlings, it is appropriate to choose the muddy sandy middle and low tide areas with low wind and waves, slow flow rate and fresh water injection (the dry dew time of the tide is 3-4 hours). The suitable salinity of sea water during the seedling collecting period is 17 ‰ ~ 20 ‰, so in this salinity range, the oyster larvae secrete the most glue, once attached to the seedling collector, it is not easy to fall off, and the seedling collection effect is good. In addition, the parental shellfish resources (i.e. second-and third-year-old oysters) should be abundant in the seedling collection area. At the peak of seedling collection, the number of oyster larvae per cubic body of water reaches 250 million 300 before enough oyster seedlings can be collected.

2. Specifications and manufacture of seedling collectors:

1. Specification of seedling collector (cement column). Specifications vary from place to place, but most of them are flat, with wide 78cm, high 5~6cm and long 60~80cm. Too large cement column is not conducive to operation and transportation, and too small affects attached seedlings and unit yield.

2. Cement column making. Mix the cement (high grade), yellow sand and pebbles with water, pour them into the wooden mold frame, tamp, smooth and polish. In the processing and manufacture, two thin steel wires which can increase the breaking strength should be placed parallel in the middle of the cement column (both ends are not exposed).

Third, the season and method of collecting seedlings:

1. Seedling collection season. The oyster species and the sea environment are different, and the seedling collection season is also different. The breeding season of pleated oysters in the coastal areas of Zhejiang Province is concentrated in late spring and early summer. The oyster seedlings collected from "the Summer Solstice" to "Lesser Heat" are of the best quality, commonly known as "moldy seedlings", with strong physique, large size, uniform seedling attachment and fast growth, while the oyster seedlings collected in August, commonly known as "buckwheat black", have weak physique, small size, high density and poor quality. Within half a month of the first spawning peak of parent shellfish (oysters over two years old), seedling collectors should be put into the sea area at the right time, which is easy to deposit and attach barnacles and water yun too early, so as to encroach on the attachment site of oyster seedlings and affect the number of attached seedlings; if it is released too late, the attached seedlings will be too dense or miss the seedling collection season.

2. The way of collecting seedlings. One is the cluster vertical style. Several cement columns are inserted obliquely into the mud and form a "human" scaffolding or cluster with each other. The second is horizontal pillow type. Two cement columns are laid in parallel on the beach (about 60cm apart), and then several cement columns are placed side by side on them.

Fourth, transfer and fattening:

1. Transfer. After 3 or 4 months of cultivation, the oyster seedlings should be "deep moving and sparse culture" as soon as possible, and the dense cement columns in the seedling collection area should be moved to the low tide area for sparse culture, so as to prolong the feeding time of oysters and obtain sufficient bait, and at the same time make room for seedling collection next year. The seedlings of early-moving oyster grow fast, the individual is large, and the meat is fat.

2. Fattening. Five to six months before the oyster harvest, the cement column will be moved to the muddy beach with fertile water quality and high flow rate for fattening. Fattened oysters have thick shells, thick colors and full grains, and the yield can be doubled. In order to facilitate the operation and management, the cement column should be arranged in the form of "single plant direct insertion". The horizontal distance between the two plants is 40cm, the vertical distance is 70cm, every 4 behavior is one district, and the distance between each district is 4 meters. At the same time, the inserted cement column is required to be straight and neat, firmly into the mud, smooth tidal current, and convenient for ships to pass.

Fifth, strengthen the management of the paint room:

During oyster culture, the management between smears should be strengthened. If the cement column is tilted, it should be righted or re-inserted in time, and the silt and algae attached to the oyster shell should be removed. At the same time, pay close attention to weather changes, such as summer and autumn typhoons and torrential rains often wash down a large number of cement columns, suffocating oysters in the mud, so it is necessary to repair the oyster beach, straighten the cement column and reduce the loss. In addition, in order to eliminate all kinds of predatory fish such as rays and crucian carp, you can catch them with fishing tackle or cut soft bamboos and branches at their entrance and exit, which can be scared off by the sound of tidal current vibration; there are also all kinds of snails, such as litchi snail, red snail, spotted jade snail, etc., which can be caught by surprise or eradicated with the same egg group during its peak period.