Aquaculture Essay Research Paper Aquaculture is the

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Aquaculture Essay, Research Paper Aquaculture is the farming of aquatic organisms in fresh, or salt water. A wide variety of aquatic organisms are produced through aquaculture, including fish, crustaceans, mollusks, algae, and aquatic plants. Unlike capture fisheries, aquaculture requires deliberate human intervention in the organisms’ productivity and results in yields that exceed those from the natural environment alone. Stocking water with (juvenile organisms), fertilizing the water, feeding the organisms, and maintaining water quality are common examples of such intervention. Most aquacultural crops are destined for human consumption. However, aquaculture also produces bait fishes, ornamental or aquarium fishes, aquatic animals used to augment natural populations for

capture and sport fisheries, algae used for chemical extraction, and pearl oysters and mussels, among others. Aquaculture is considered an agricultural activity, despite the many differences between aquaculture and terrestrial agriculture. Aquaculture mainly produces protein crops, while starchy staple crops are the primary products of terrestrial agriculture. In addition, terrestrial animal waste can be disposed of off-site, whereas in aquaculture such waste accumulates in the culture environment. Consequently, aquaculturists must carefully manage their production units to ensure that water quality does not deteriorate and become stressful to the culture organisms. History Aquaculture was developed more than 2000 years ago in countries such as China, Rome, and Egypt. Not long

after, aquacultural practices in Europe, China, and Japan commonly involved stocking wild-caught seed?for example, carp fingerlings (juvenile fish) captured from rivers?in ponds or other bodies of water for further growth. Mollusk culture was advanced in the 1200s by the discovery in France that mussel spat (newly settled juveniles) would settle on upright posts in the intertidal zone, and in the 1600s by the discovery in Japan that oyster spat would settle on upright bamboo stakes driven into the sea floor. The concept of pond fertilization was developed in Europe about 1500. In this process, manure is added to the water to encourage the growth of small organisms such as aquatic invertebrates and plankton, which in turn are eaten by the fish. The United States system of federal

hatcheries for the breeding of anadromous fishes (fishes that live and mature in salt water but reproduce in fresh water) was established in the 1870s. Much of the current technology used to reproduce fish in hatcheries has been developed by these federal hatcheries. In 1959 the first marine shrimp hatchery and farm was established in Japan, and it was the forerunner of the commercial shrimp-culture industry. The salmon-culture industry in Europe and the channel-catfish-culture industry in the United States both began in the 1960s. Methods Most fish and crustacean aquaculture is undertaken in earthen ponds. These ponds are usually equipped with water inlets and outlets that permit independent control of water addition and discharge. Ponds are stocked with a specific quantity of

juvenile aquatic animals. Management practices range from pond fertilization, which increases the number of natural food organisms, to provision of a complete, formulated feed that supplies all nutrients necessary for growth. Animals that have reached market size are harvested from the ponds. In a complete harvest, the pond is drained and all animals are removed from the pond for processing. In a partial harvest, only a portion of the animals are removed from a full pond using a seine net. Additional juveniles are often stocked into the pond after a partial harvest, and the production cycle is continued. Channel catfish grown in the United States, and marine shrimp grown in China, Central America, and South America, are often cultured in earthen ponds of about 5 to 10 hectares