Lin Tou Pearl Clams

Lin Tou Pearl Clams

Lin Tou Pearl Clams are a geographical indication certification trademark.

　　Zhao’an County is located along the southeast coast, at the border of Fujian and Guangdong provinces, adjacent to Raoping County in Guangdong. Its geographical coordinates are between 116°55′—117°22′ east longitude and 23°35′—24°11′ north latitude. It enjoys a South Asian tropical maritime monsoon climate with ever-spring-like seasons, abundant sunshine, a pleasant climate, and plentiful rainfall. The area receives an average annual rainfall of 1447.5 millimeters, with an average temperature of 21.3°C. Winters are not severe and summers are not scorching. The county has a well-developed water system, with major rivers including the East River and the West River. The total freshwater area covers 68,000 mu, and the marine fishing resources are abundant, yielding high-quality seafood such as mud clams, blood clams, swimming crabs, and oysters. Locally, mud clams are commonly called “blood clams,” and “Lin Tou Pearl Clams” are the premium variety among them. They are abundantly produced along the beach area of Lin Tou Village in Sidu Town, Zhao’an County. The clam farming grounds here feature flat terrain and unique water quality where the freshwater from the East River meets seawater. The muddy yet fertile beds offer optimal conditions. The farming areas consist of muddy-sandy or sandy-muddy intertidal zones, with a mild climate and an average annual water temperature of 20.9°C. The waters are clear and transparent, with smooth tidal currents, a seawater specific gravity of 1.022–1.025, and a water temperature range of 9.6°C–10.25°C. The intertidal zone boasts rich biomass, with blue-green algae and diatoms being the most numerous phytoplankton, and a predominance of tropical and warm-water copepods, krill, and mysids, all conducive to shellfish growth. The superior natural environment and unique geographical conditions give “Lin Tou Pearl Clams” their signature round shape resembling large pearls, light tan shells that are thin yet hard with fine, densely packed ridged lines, white inner flesh, crisp and tender texture, rich hemolymph, balanced salinity, and a sweet taste. The clams are not only rich in protein, vitamins, and trace elements such as potassium, magnesium, calcium, iron, and selenium, but also have a high proportion of beneficial fatty acids including linoleic acid, eicosapentaenoic acid (EPA), and docosahexaenoic acid (DHA). The farming of “Lin Tou Pearl Clams” has a long history, gaining fame since the Qing Dynasty and becoming especially popular in Southeast Asian markets.

　　Before the Han Dynasty, Zhao’an already had a freshwater fish farming industry. During the Ming Dynasty, tidal flat aquaculture emerged. After the founding of the People’s Republic of China, aquaculture was given greater attention, with increasing farming areas and yields for species such as mud clams. In 1963, the Provincial Aquatic Products Bureau established a mud clam farm in Meiling, releasing a large number of parent clams and creating a thousand-mu seedling base to breed abundant clam spat. By the mid-1970s, Sidu Town in Zhao’an County successfully developed large-scale artificial cultivation of pearl clams along the coast, further promoting the growth of “Lin Tou Pearl Clam” farming. Through years of active development, “Lin Tou Pearl Clam” farming has become a significant industry for the county’s economy. According to a survey at the end of 2010, the county had 5,000 mu of clam farming beds, yielding 5,000 tons of pearl clams annually and generating over 100 million yuan in output value.

　　To guide clam farmers in scientific cultivation, the Zhao’an County Aquatic Technology Extension Station promotes scientific clam farming through measures such as organizing training sessions and advocating tidal flat water storage methods. These efforts help standardize the clam farming process, thereby improving the quality, yield, and market competitiveness of the clams, enabling farmers to achieve increased production and income.

　　The Zhao’an County Aquatic Technology Extension Station is a public institution registered and approved by the Zhao’an County Personnel Bureau. It operates under the Zhao’an County Ocean and Fisheries Bureau. Its primary responsibilities and scope of business include conducting research and investigations in collaboration with government authorities. Based on the realities of the aquatic industry, it provides advice and strategies to government departments on major issues affecting the industry and enterprises, such as industry standards, sector development, and industrial policies. The station also establishes and improves self-regulatory mechanisms within the industry, coordinates with member organizations and industry stakeholders to develop industry codes and agreements, mediates relationships both within and outside enterprises, explores effective mechanisms for self-management and self-discipline, promotes fair competition, and enhances the overall quality of the industry.

　　The production region for products using the “Lin Tou Pearl Clam” certification trademark is within the administrative area of Zhao’an County, Fujian Province, People’s Republic of China, specifically between 117°10′–117°21′ east longitude and 23°21′–23°47′ north latitude. This includes 13 administrative villages across three towns: Donggetou, Yancang, Lin Tou, Xizhang, Gangkou, Dongwu, Xiwu, Tianpu, Shanhou, Xunliao, Yuanqian, Qiucheng, and Shitou (Anyu Village).