Courtesy United Nations
In the 1980s, the fisheries sector was of major importance to the economy as an earner of foreign exchange, marine products accounting for about 10 percent of total exports in 1986. Fish also accounted for about three-fifths of the protein in the national diet and an even higher proportion among the poorer rural population. Until the early 1960s, the country had been a net importer of fish. This situation completely changed with the introduction of trawl fishing, which resulted in a dramatic rise in the marine catch from 146,000 tons in 1960 to 1 million tons in 1968 and 2.1 million tons in 1985. Thailand became the third largest marine fishing nation in Asia after Japan and China. Of Thailand’s 40,000 fishing vessels, nearly 20,000 were deep-sea trawlers, many with modern communication and navigation equipment and refrigeration facilities.
By 1980 large-scale fishing operations, based largely in urban areas, were responsible for 88 percent of Thailand’s annual catch. The fishing industry was the economic backbone of many Thai coastal cities. The increase in the catch of shrimp was particularly notable, and shrimp exports became a major source of foreign exchange earnings. By about 1972 maximum exploitation of demersal (bottom-dwelling) and pelagic (open-sea) fish appeared to have been reached in the Gulf of Thailand and in the Andaman Sea. In the early 1980s, production remained relatively static, and there was growing concern that these areas were being overfished.
Government control of fishing was limited. The use of certain kinds of fishing gear within three kilometers of the coast was banned, but there appeared to be no restriction on trawl net-mesh size, and undersized commercial food fish were being caught and dumped in with trash fish in the production of fishmeal. Moreover, during the 1970s neighboring Cambodia claimed territorial waters extending to 200 nautical miles from its coast. This reduced the area in the Gulf of Thailand available to Thai fishermen and increased the intensity of fishing off the coast of Thailand. Similar claims by Burma had also restricted Thai fishing in the Andaman Sea.
Inland fisheries, which included both freshwater and brackish water fish, officially reported annual catches of about 160,000 tons in the early 1980s. The actual catch--principally freshwater fish from flooded rice paddies, swamps, irrigation and drainage ditches, canals, reservoirs, rivers, lakes, and ponds--was estimated to be much higher. It was believed, however, to be declining as population growth resulted in overfishing and as increasing water pollution from industrial waste, insecticides, and siltation caused by forest destruction took its toll.
The most promising course for maintenance of fisheries production at the level attained in the 1970s, or for increasing output, was the expansion of aquaculture, including the culture of fish, shrimp, and various mollusks, such as mussels, oysters, and clams. According to the Department of Fisheries, about 4.5 million hectares of inland water areas, mostly rice paddy fields, were suitable for aquaculture. Another 1.3 million hectares, including estuaries, mangrove swamps, and tidal flats, were also usable (see thailand/th_appen.asp#table13"> table 13, Appendix).