The Knowledge Of Oyster

Oysters (scientific name: Ostreidae) is the pearl shellfish, oyster family of mollusks collectively known as oysters, oysters and so on. The shell is nearly long, round, triangular, affected by the external environment, the shell shape is very irregular. The two shells are unequal, the left shell is larger and convex, and the camp is attached to life, and the right shell is slightly smaller and flatter. The outer surface is scaly, easy to fall off, a few species of radiating ribs are obvious, and some of the oyster shells are covered with spines. The top cavity of different species varies greatly from shallow to deep. The hinge has no teeth, and the ligament groove is developed. 1 closed shell muscle, muscle marks obvious, brown or colorless, no foot and byssus.

Living habits

Stress resistance

Oysters are also one of the most stress-resistant aquatic animals. The changeable environment of the intertidal zone over the past 200 million years has trained oysters' strong resistance to temperature, salinity, open air and common diseases in the sea area. When the ebb tide comes out of the water, oysters can withstand the hot and dry weather in summer, and can also successfully adapt to the freezing weather in winter. Maybe even a month.

Vertical distribution

The vertical distribution of oysters varies with the species. But most of the economic species are distributed in shallow water and intertidal zone. In the natural sea area, the vertical distribution of all kinds of oysters is relatively stable, and generally distributed in the water depth of intertidal zone and subtidal zone is not more than 10 meters. For example, crassostrea gigas lives in the intertidal zone and near the low tide line, and crassostrea gigas inhabits the low tide line to the water depth of about 10 meters.

Attached metamorphosis

To act as a shell adhering to another object. Generally distributed in the intertidal zone and subtidal zone water depth of no more than 10 meters. Oysters stick by sticking their shells to other objects. The attachment and metamorphosis of oyster is an important stage in its development, which directly determines the survival rate of oyster. The occurrence of metamorphosis has also changed many physiological activities of oysters. Under normal circumstances, the eye spot larvae that are about to attach first crawl on the attachment with their feet, and when they meet a suitable place, the byssus glands secrete byssus and attach themselves to the attachment. After the left shell is installed, the adhesive substance is released from the body and fixed on the attachment. If the environmental conditions are not suitable, this series of processes is difficult to complete. To reduce or prevent the larvae from becoming fixated. Many factors affect the attachment and metamorphosis of oyster larvae. But mainly from two aspects, one is salinity, it depends on the type, too high, too low will affect the development of byssus gland and glue material secretion and viscosity strength; The second is a suitable attachment base.

Feeding characteristics

Filter feeding. It feeds on microscopic algae and organic debris in the ocean.

Distribution range

The distribution of oysters is very wide, in addition to the poles, from the equator to the subfrigid waters everywhere, but oysters are mainly distributed in temperate and subtropical areas. In the case of a particular species, its range is determined by its ability to adapt to the external environment, especially temperature and salinity. The adaptability to temperature and salinity is strong, and the distribution is wide, whereas the distribution is narrow.

China has abundant oyster resources and is the hometown of oysters. There are oyster production bases in Bohai Sea, Yellow Sea, East China Sea and South China Sea, and the major producing areas are Fujian, Guangdong, Shandong, Guangxi, Liaoning and Zhejiang. Among them, crassostrea gigas is the most important cultured species.