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Aquaculture
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Aquaculture is a form of agriculture that involves the farming of aquatic plants and animals in a controlled environment. It has been practiced for nearly 4,000 years, but has not become commercially viable until recently. Aquaculture has yet to undergo an "Aquacultural Revolution" similar to the Agricultural Revolution of the 1700's, but the beginnings of such an event are starting to become visible. One of the main reasons for aquaculture's popularity lies in its efficiency. "Beef cattle require seven pounds of grain to produce one pound of meat. Catfish require only 1.7 pounds of grain to produce 1 pound of fish (Boychuk, 20-21). With the decline of commercial fishing, aquaculture profits have increased. For example, Maine's long- standing commercial fishing industry made 94 million in 1996, and has since been in decline. (Williams) On the other hand, Maine's aquaculture industry made 57.5 million in the same year, over half of the commercial fisheries' profits. (Williams) Aquaculture involves a wide variety of species, including salmon, prawns, oysters, shrimp, milkfish, and even seaweed. One of the most popular forms of aquaculture is fish farming. "According to the United Nations Food and Agricultural Organization, fish-farming is a $40 billion-a-year business, accounting for about 20 percent of all fish consumption" (Ackerman). Aquaculture also constitutes 12 percent of the world's fish harvest. (Boychuk, 20-21) Some of the most prevalent aquaculture fish species include salmon, catfish, and tilapia. In the United States, half of all fish-farm production consists of farm-raised catfish. Aquaculture also has the potential to provide employment for large numbers of people. "If the aquaculture industry in Maine equaled that of Norway, it would provide 9,000 jobs in this state, more then Bath Iron Works, the state's largest employer. (Williams) In the United States and Europe, salmon farming is one of the more common forms of agriculture. "Most of the major salmon farms in Maine, which account for more then 90 percent of the states aquaculture harvest, can supply fish to markets year round." (Williams) In the island state of Hawaii, Royal Hawaiian Farms' salmon farms are capable of producing 4 million pounds of salmon annually" (Loupe, 22-27). Salmon farmers use a variety of techniques to ensure that the highest possible number of fish survive to reach adulthood. Baby fish are fed three times a day, increasing the survival rate to 30 percent. Young salmon -- also known as smolt -- are vaccinated and fed antibiotic fish meal to prevent disease. Vacuums beneath the salmon pens up wastes and excess food in order to prevent water contamination. Most fish farms have methods to dispose of biological wastes, but another aquaculture species is not so fortunate. In Southeast Asia and South America, shrimp are grown in tiny pools of brackish water. These pools become toxic after about a year, due to the concentrations of of waste and uneaten food that build up on the bottom. Once the water becomes unfit for use, the farmers are forced to move on, often cutting down acres of mangrove swamps. "Shrimp ponds have led to the destruction of thousands of hectares of mangrove forests. They've also generated steady flows of polluted wastewater and contributed to the decline of wild shrimp fisheries" (Boychuk, p.20-21) However, the problem is not easily solved. Many poor people in Third World countries rely on shrimp farming to provide income. "In Ecuador, for instance, 230,000 people earn their livings working for shrimp farms, and a fifth of all the households in the country's coastal provinces are dependent on the farms for their income" (Science p.80-81) Also, shrimp farming is a lucrative business, with the retail value of farmed shrimp at about 16 billion annually. (Science, p.80-81) Shrimp farming has the potential to become a major industry if a solution can be found for many of its current problems. While most people would agree that shrimp and fish are aquaculture species, it is unlikely that one would consider algae to also belong in that category. Algae are best described as simple plants that live in water. They can form larger structures such as seaweed, but they have little or no specialized tissues. One species of algae, nori, is farmed all over the world. "Nori is perhaps best known as the seaweed wrapper used for sushi, the Japanese dish of raw fish and vegetables. It is also used in other dishes, including soups, and is considered a valuable source of vitamins and minerals" (Grant, 1). Nori has yet to become a common food in the U.S., but the dried green sheets of algae are prized by heath food enthusiasts. Nori also contains pigments worth almost $300 per milligram; it has many other possible uses in both science and medicine. (Grant, 1) There are a number of ways nori can be grown, but one of the most innovative involves pumping seawater from the deep ocean through tanks of nori. Deep seawater contains surprisingly few contaminants or living organisms, qualities that make it ideal for aquaculture. "The seawater's purity provides a disease-free environment, important for products that will ultimately end up on someone's dinner plate" (Loupe, p.22-27). Aquaculture is still in its infancy, and many problems remain to be dealt with. Some are relatively minor, like the problem of disease prevention in a crowded tank. Others are more important, such as the destruction of mangrove swamps, and some problems have the potential to be deadly. "Intensive coastal fish farming has also been linked to 'red tides' -- an explosive growth of toxic algae that can kill fish and fatally poison people who eat contaminated seafood" (Boychuk, 20-21). When the difficulties and costs of aquaculture are overcome, an "Aquacultural Revolution" will commence; a revolution in the way mankind views and thinks of the sea. Works Cited
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