Offshore aquaculture refers to the use of shrimp ponds, cages, rafts, fixed nets and other aquaculture methods to carry out various forms and levels of aquaculture activities in coastal shallow waters. The shrimp culture in China has developed rapidly, with an annual output of 6.5438+0.65 million tons (excluding Taiwan Province Province), accounting for 29.2% of the world's shrimp culture. With the maturity of shrimp culture technology, the output of shrimp culture has increased year by year, from more than ten kilograms per mu to 200 ~ 400 kilograms. There are 44 species of shellfish cultured in the world. According to the statistics of FAO, the output of oysters is the highest, and the output of mussels and scallops ranks third. China and Japan are countries with more shellfish culture in the world. According to the current development speed of cultured shellfish, it is estimated that the world shellfish output will reach 7.6 million tons by the end of this century. With the increase of artificial shellfish breeding varieties and the expansion of production scale, natural shellfish fry can no longer meet the needs of production development, which correspondingly promotes the development of industrial shellfish breeding. At present, the output of shellfish culture in Asia accounts for about two-thirds of the world's total output. The history of seaweed culture is not long, and the main breeding varieties are kelp, Undaria pinnatifida, laver and laver. The level and mode of offshore aquaculture largely depend on the products, locations and methods of aquaculture.

Intensive farming is widely used in developed countries, and its farming level is driven by market economy and resource competition, which will last for some time. In developing countries, decentralized or semi-intensive agriculture is the main method. Although it occupies a large sea area, its management level is poor and its output is not high.