What is Aquaculture?
Aquaculture is the controlled growth of marine and freshwater organisms in man-made structures and occurs throughout the world. Fish and other marine organisms (such as oysters, shrimp, and conch) are cultured. Most aquaculture systems use ponds, tanks, raceways, cages, or pens to enclose the cultured organisms.

History of Aquaculture
Aquaculture began over 4,000 years ago in Asia. Man-made ponds were stocked with wild caught marine organisms. Hieroglyphics indicate that Egyptians in the Middle Kingdom also practiced aquaculture, and Romans were not without their aquaculture, as they were known to have cultivated oysters.

Aquaculture began in the United States in the 1700's, and aquaculture in its modern form began in 1733 in Germany when German aquaculturists collected fish eggs, fertilized them, and grew the hatched fish. However, this spawning was with freshwater fish, mostly trout. It wasn't until the 20th century that techniques were developed to spawn marine species.

Today, with select organisms, broodstock - sexually mature males and females - are held at hatcheries, and these broodstock are spawned and the fertilized eggs collected and hatched. The offspring become fry - juvenile fish used to stock an aquaculture system. In this system, only a few fish are taken from the natural environment to be used as broodstock - larval fish are not collected to stock the aquaculture facility.

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Why Aquaculture is Needed?
Throughout history, humans depended upon the ocean as a source of food. Traces of early settlements are discovered near rivers, lakes, and oceans for this reason. With the low-tech fishing methods of the past and the relatively small population of the world, the catch was small compared to the ocean's ability to replenish this renewable resource. However, as technology and the global population advanced, fishers began to take more fish than the ocean could sustain. This has led to many stocks of fish being overfished, and once a stock is overfished, recovery is often very slow. Aquaculture allows catches to remain at a sustainable level while allowing total fish consumption to rise, helping to prevent the demise of fish stocks.

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Aquaculture Systems
Currently, aquaculture system use ponds, tanks, raceways, cages, and pens. Ponds can have a soil bottom or a liner bottom and is commonly used for bottom dwelling fish and other organisms that do not swim in the water column, such as shrimp. Tanks are circular or rectangular structures, usually made of glass or fiberglass, and range from very small to medium in size. They are often used for hatchery operation, as well as culturing small organisms, such as ornamental fish. Raceways are larger than tanks and are much longer than wide, allowing water to move from one end to the other. Larger, more mobile, fish can be cultured in raceways, but a sophisticated filtration system may be necessary, as well as an aeration system. Cages and pens are used for nearshore and offshore (also known as open ocean aquaculture or OOA) aquaculture and can be either floating or submerged. Cages and pens are used to grow a variety of finfish, including cobia, seabream, snapper, moi, and others.

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Problems with Aquaculture
While aquaculture has the potential to benefit the environment by limiting catch of wild organisms, if done improperly environmental degradation occurs. Some of the problems of aquaculture include destruction of mangrove forests, water pollution, antibiotics and pesticides, escapement, and seafloor damage.