Linden J. ELLIS and Jennifer L. TURNER

A group of men fishing the Shimei beaches, Wanning Xian, Hainan Island. PHOTO BY JOAN LEBOLD COHEN.

Seafood is already a staple in the Chinese diet, but domestic consumption is projected to rise 40 percent by 2020. Of China’s total seafood output, 64 percent comes from aquaculture (the farming of aquatic life), making it the only country in the world where the amount of cultivated seafood is greater than the wild catch.

Aquaculture—the farming of any aquatic life, including freshwater and saltwater fish, mollusks, shellfish, crustaceans, and plants—is a vibrant industry in China. Several varieties of carp compose most of the cultivated freshwater species; shellfish dominate the saltwater market. However, as China’s population becomes wealthier, demand is growing for higher-value species—notably grouper—which require high inputs of “trash fish,” thereby putting an increasing strain on wild stocks around the world. Aquatic plants, such as kelp, account for 27 percent of total aquaculture output. Since 1978, China’s aquaculture production has increased 490 percent, making it now the largest in the world, and accounting for 57 percent of the global output.

Aquaculture is China’s largest “farmed” export, with Japan, the United States, and South Korea as the main destinations. Local governments promote aquaculture as a poverty-alleviating industry and have therefore subsidized production of lucrative species such as tilapia. China supplies 70 percent of the tilapia imported into the United States and is also its fourth largest supplier of shrimp (shrimp and tilapia are the first and fifth most popular seafood, respectively, of U.S. consumers).

Aquaculture is practiced all over China and aqua-cultivated areas are increasing, with carp farms being the most widespread. However, other fish are restricted to regions for climate and environmental reasons. For example in 2006, Guangdong, Guanxi, and Hainan produced 81 percent of the nation’s tilapia; Hubei, Sichuan, and Jiangsu produced 56 percent of the nation’s catfish; Shandong, Fujian, Guangdong, and Liaoning provinces accounted for 80 percent of the total shellfish production; shrimp and prawns are produced mainly in Guangdong as well as Jiangsu, Guangxi, Zhejiang, and Hainan; and eel is produced mainly in Fujian, Guangdong, and Jiangxi.

Because China’s waterways are highly polluted, food safety has become a major concern for Chinese aquaculture. Besides municipal and industrial wastewater contamination, mercury emissions from China’s coal-fired power plants are another potential source of aquaculture contamination. Statistics on mercury in Chinese fish are scarce, but Chinese coal is believed to be responsible for much of the mercury contamination in fish in the western United States.

International concern about food safety has cost China’s aquaculture dearly, as countries ban species they have discovered to be contaminated. Two major cases include the 2005 eel bans in Japan and the 2003 shrimp bans in the European Union—both devastated these important aquaculture sectors in China. Chinese consumers also are increasingly concerned about water pollution, dangerous farming practices, and poor processing in the aquaculture industry that pose serious threats to human health. The rapid development of China’s aquaculture industry is also a major polluter of rivers, lakes, and coastal waters. Moreover this industry’s huge demand for fishmeal is driving stock depletion in the oceans.

Environmental Impacts

Raising carnivorous species, such as salmon and shrimp, tends to produce some of the most detrimental environmental impacts because of the amount of antibiotics and waste they produce. However, hardier herbivorous fish that require fewer chemical and organic inputs can also create environmental problems when they are farmed too intensively. In China, the high-density farming of herbivorous fish increasingly faces the same challenges of disease, overmedication, and nutrient runoff as the country’s concentrated land-animal feeding operations. Some environmental impacts causing concern domestically and internationally include:

Oxygen Depletion and Algae Blooms

Runoff of uneaten food and effluent from fish farms is a growing problem in China. In the past, freshwater fish fed off naturally occurring organic material in ponds. However, the intensification of farming and the increased use of manufactured feed has led to more uneaten food, effluent, and pollutants in the waterways; this can cause eutrophication, the uncontrolled growth—and decomposition—of algae and other organisms that deplete the oxygen supply in the water, choking other life forms. For example, shrimp consume only 20 percent of their food on average; the rest washes out to sea or settles into the soil, fouling the ponds.

Antibiotics, Pesticides, and Fungicides

Many fish farmers are individuals, rather than companies, and they often over-apply or misuse antibiotics, pesticides, and fungicides to clear the water of other creatures, reduce parasites, control disease, and boost weight gain of seafood grown in severely overcrowded conditions. Antibiotics, either applied directly to the water or that have passed through the fishes’ digestive systems, are not biodegradable and persist in the surrounding environment, threatening wild fish stocks.

Habitat Destruction

Lucrative fish markets prompted many Chinese rice producers in the early 1990s to switch into intensive aquaculture production. This trend, in conjunction with rapid urbanization, raised concerns about grain security and led the Chinese government in 1994 to establish the Basic Farmland Protection Regulation, which enforced a zero net-loss of grain or oilseed farmland. Nevertheless, China’s aquaculture output continues to rise as more natural bodies of freshwater and more marine coastline are converted into fish farms. Diseases and pollution from overcrowded fish farms, particularly shrimp pools, are often pumped out into natural waterways, endangering native species.

Monoculture and Invasive Species

A major challenge for aquaculture is the need for fast-growing species that can withstand the conditions of farms, namely overcrowding and high levels of nutrients and ammonia. Monoculture of these fast-growing fish can lead to a reduction in genetic diversity and makes farms susceptible to diseases. The quest for fast-growing species also brings in foreign species that can become invasive. Amazonian snails, for example, were imported for food and are responsible for decimating 1,600 square kilometers of farmland in China, and countless acres of natural habitat. The other disadvantage of this type of farming is the possibility of an epidemic disease that destroys the stock. Before 1993, China was the world’s top shrimp producer until an epidemic of white spot decimated the shrimp population. The market has never fully recovered.

Food Safety Concerns

The Ministry of Health (Luan 2007) reported in March 2007 that 196 people died of food poisoning in China the previous year. Unsafe and undercooked aquacultural products are an integral component of this total figure. A major challenge to food safety in China is the structure of the aquaculture industry. First, there are many widely scattered players involved in the production of the feed, the farming and the processing. It is thus highly challenging, and expensive, to standardize and monitor the veterinary care and processing of t
he fish. Second, there is a strong preference for live and undercooked fish in China, increasing the risks to consumers and highlighting the need for timely monitoring and testing.

While the Ministry of Health issues the regulations, food safety rests essentially in the hands of local government enforcers, which in the case of aquaculture often lack the motivation or capacity to monitor strictly. According to the Chinese scientist Lei Jilin in an interview with Xinhua News Agency, the local government agencies entrusted with monitoring fish-related food safety are either doing their jobs poorly or not at all. The Shanghai food-quality inspections appear to be the most successful, as they are often the first to discover large safety mishaps. Further complicating the food-safety issue and eroding consumer trust is the fact that, while investigations are publicly announced, the findings of the investigations of farms and market studies are often not publicized.

One final concern regarding herbivorous fish is the farming practice of using human and animal waste as feed. This practice has proved particularly suspicious with regards to avian influenza around Qinghai Lake where thousands of migratory birds fell ill in 2005 near several large carp farms and feed-manufacturing facilities. There is some speculation that poultry-litter-based fish feed may have played a role in spreading this disease to wild bird populations.

High-Profile Aquaculture-Related Food Scares from 2006 to 2007

? 14 October 2008: Fish in Lake Tai found to contain an excessive amount of formaldehyde.

? 19 February 2008: China recalls pesticide-tainted mackerel from Japan two weeks after tainted dumpling scandal. Although these are believed to be added at the manufacturing stage, they still impact China’s seafood trade.

? 30 April 2007: The New York Times (Barboza & Barrionuevo) reported that melamine scrap, believed to have sickened 14,000 U.S. pets, is commonly used in fish feed in China. Melamine is added to animal feed as a synthetic nitrogen enhancer, making the feed appear to have more protein and increasing its value.

? 26 April 2007: Wal-Mart removed Chinese catfish from U.S. stores due to antibiotic contamination. It was the state of Alabama, not the U.S. Food and Drug Administration, that discovered the contamination.

? November 2006: Eleven out of fifteen samples of Mandarin fish from China tested positive for malachite green in Hong Kong.

? 22 November 2006: Carcinogens (chloramphenicol, malachite green, and furazolidone) were found in turbot in Shanghai. Turbot sales were subsequently suspended in Shanghai, Beijing, Shenzhen, and Taoyuan. Turbot is a species of flatfish with low disease-resistance that requires considerable and careful veterinary input. One hundred percent of the Shanghai sample tested positive.

? October 2006: Taiwan banned imports of hairy or mitten crabs from China due to traces of carcinogens.

? August 2006: 87 people were diagnosed with meningitis after eating raw or undercooked Amazonian snails in Beijing.

Some Positive Steps

With wild catch rapidly decreasing due to over-fishing and pollution in China’s freshwater and coastal areas, China must increasingly turn to aquaculture to supply its protein base. The trouble with aquaculture is essentially twofold: It uses rudimentary and even dangerous farming practices, and it has weak or nonexistent food-safety monitoring. The effect is environmental degradation and compromised human safety in both domestic and foreign markets.

Development of Safer Feeds and Farming Methods

With aquaculture and demand for fish rising substantially in China, fish farming is intensifying. Feed is a major source of concern and an integral part of intensification. The Chinese government’s priority for food security has led it to commit considerable resources to agricultural and fish research that has produced some promising new options for feeds, fish species, and farming practices. Such research holds the promise of promoting ecologically safer fish-farming practices that also will help protect human health and limit China’s use of wild ocean fish as fishmeal. Some new feeds being developed include:

? Yeast-based feed. According to World Resources Institute, “Chinese researchers are developing a protein supplement based on yeast that can substitute for more than half the fishmeal in aquaculture feed preparations.”

? Soy-based feed. As of 2007, China’s aquaculture industry used 4.5 to 5 million metric tons of soy meal a year (Ellis & Turner 2007). Some species, such as tilapia, one of China’s staple fish, can tolerate 50 percent soy in their diets. Other high-value fish can tolerate only 10 percent soy; however, even a small reduction in ocean fishmeal dependence will relieve some stress on global oceans.

Another area of research is identifying fish species with higher survival rates and faster growth rates that may reduce the need for chemicals to sustain profitable production.

Integrated polyculture systems, once the norm in China, are a more sustainable solution. One living example is the rice-field carp of Qingtian in Zhejiang Province. In Qingtian, terraced rice patties were stocked with carp by naturally flowing river water. However, farmers have intensified carp production with the addition of manufactured fish feed and by erecting concrete barriers to deepen their ponds. The damming of such rivers to create carp pools has led to increasing problems of eutrophication, interrupted water supply to farms and communities, and diseased fish. In order to encourage a return to a more environmentally friendly integrated polyculture system, the government could develop a new certification for organic rice-patty carp, which could help the Qingtian farmers create lucrative markets in the nearby tourist centers of Hangzhou and Suzhou.

Food Monitoring a New Priority

As is true in the case of other environmental and health challenges in China, many superb laws exist, but monitoring and enforcement tend to be weak. During the 2006 turbot scare, it merits mention that the three farms highlighted by name as responsible in the Chinese news media were subsequently fined and ordered to suspend sale for violating bans on antibiotics in fish. The 2008 Olympic Games played a positive role in accelerating food safety progress in the Beijing area primarily by creating a “safe list” of food suppliers, which notably has been done in Hong Kong with aquacultural products from Guangdong, but there is still much to be done to address the systemic regulatory failures in the vast aquaculture system that most dramatically affect those outside big cities. Some positive trends include:

? March 2007: The Ministry of Health released a draft of a new food safety coordination law to the public via the Internet.

? March 2007: The Fresno Bee reported that Global Food Technologies signed an agreement with the China Seafood Certification Institute to develop a branded food safety program for seafood beginning with one billion pounds of seafood by the end of 2009.

? November 2006: The Fisheries Bureau of the Ministry of Agriculture announced a nationwide inspection targeting forbidden chemicals in the fish market.

As China develops, seafood will no doubt continue to play a major role in nutritional security as well as food safety. However, with the population becoming more wealthy, red meats and high-value fish species, such as grouper, salmon, and black seabass will take greater market shares at an ever higher threat to the environme
nt. Increasing domestic demand for processed, rather than live, seafood will present new food safety challenges to the developing food-safety system. In the last two years, international and domestic pressures have led the central government to shift its focus to food safety, particularly in seafood. Given the chronic shortages of land and water in China and continuing population growth, regulators and policy makers must continue to prioritize the food production and distribution systems to conserve resources and protect human health. There is great opportunity to increase production through more scientific farming practices.

In terms of exports, China’s aquaculture is being more scrutinized. After the food bans in 2007 from major importers, China will no doubt diversify its sales. The United States has taken a proactive approach to continuing trade in aquaculture by signing an agreement between the Department of Health and Human Services and the General Administration of Quality Supervision, Inspection and Quarantine to cooperate and streamline the inspection process for Chinese aquaculture. In 2008, the U.S. Food and Drug Administration also opened offices on the ground in China, which will play a role in this process.

Further Reading

Barboza, D. & Barrionuevo, A. (2007). Filler in animal feed is open secret in China. New York Times. Retrieved November 24, 2008, from

Bean, C., & Wu Xinping. Fishery products: China’s tilapia production situation. USDA Foreign Agricultural Service Global Agriculture information Network Report CH6029. Retrieved November 24, 2008, from

Cancer-causing fish slip through food safety supervision net. (2006). Retrieved November 24, 2008, from

Drugs used in the salmon farming industry. (n.d.). Retrieved November 24, 2008, from

Ding, Chengri. (2004). Farmland preservation in China. Land Lines 16(3).

Edwards, P. (2006, October-December). Rural aquaculture: Recent developments in Chinese inland aquaculture. Aquaculture Asia Magazine 11(4), 3–6. Retrieved November 24, 2008, from

Ellis, L., & Turner, J. (2007). Food safety: Where we stand in China. Retrieved December 8, 2008, from

Ellis, L. & Turner, J. (2007). Aquaculture and environmental health in China. Retrieved November 21, 2008, from]

Feare, C. J. (2006). Fish farming and the risk of spread of avian influenza. Wild Wings Bird Management. Retrieved November 24, 2008, from

Fish farms punished over use of banned medicines. (2006). NewsSGD. Retrieved November 24, 2008, from

Huang, Annie. (2006). Chinese hairy crab imports banned after tests find excess carcinogens. Taiwan Journal. Retrieved November 24, 2008, from

Luan Shanglin. (Ed.) (2007). Coordination of food safety inspection strengthened. Xinhua News Agency. Retrieved November 24, 2008, from

(2006). Meningitis infects 87 who ate un-cooked snails. News-Medical.Net. Retrieved November 24, 2008, from

Public Broadcasting Service. (2004). Farming the oceans. Retrieved November 24, 2008, from

World Resources Institute. (1994). Farming fish: The aquaculture boom. Retrieved November 24, 2008, from

Xie Chuanjiao & Wu Jiao. (2006). Food safety tops the menu. China Daily. Retrieved November 24, 2008, from

Source: Ellis, Linden J., & Turner, Jennifer L.. (2009). Aquaculture. In Linsun Cheng, et al. (Eds.), Berkshire Encyclopedia of China, pp. 73–79. Great Barrington, MA: Berkshire Publishing.

A fisherman carrying his “butterfly nets” in Zhejiang Province, 1979. PHOTO BY JOAN LEBOLD COHEN.

A fisherman at Guilin is aided by cormorants, trained since ancient times in China to catch and bring back fish to their owners. PHOTO BY PAUL AND BERNICE NOLL.

Aquaculture (Shu?ch?n y?ngzhí ????)|Shu?ch?n y?ngzhí ???? (Aquaculture)

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