Aquaculture is breeding, raising and harvesting fish, and aquatic plants. Aquaculture involves cultivating freshwater, brackish water and saltwater populations under controlled or semi-natural conditions, and can be contrasted with commercial fishing, which is the harvesting of wild fish.

There are two main types of aquaculture marine and freshwater. NOAA efforts primarily focus on marine aquaculture, which refers to farming species that live in the ocean and estuaries.

MARICULTURE: Mariculture, commonly known as marine farming, refers specifically to aquaculture practiced in seawater habitats and lagoons, opposed to in freshwater aquaculture.
Aquaculture has been in existence since at least 500 BCE. However, only since the mid-20th century has it assumed commercial importance. The rapid expansion of aquaculture has been to a large extent in the production of relatively high-priced species frequently consumed as a fresh product. Examples are shrimp, crayfish, prawns, trout, salmon, and oysters. However, also increasing is the production of catfish, carp, and tilapia, which are reared in extensive low-energy systems. For example, catfish farming in the United States has more than quintupled its production since it began to grow in the 1960s. Some of these freshwater fish are also utilized in aquaponics, a hybrid system that combines aquaculture with the hydroponic cultivation of plants; the fish wastes are used to feed the plants.

According to the Food and Agriculture Organization (FAO), aquaculture “is understood to mean the farming of aquatic organisms including fish, molluscs, crustaceans and aquatic plants. Farming implies some form of intervention in the rearing process to enhance production, such as regular stocking, feeding, protection from predators. Farming also implies individual or corporate ownership of the stock being cultivated. in current aquaculture practice, products from several pounds of wild fish are used to produce one pound of a piscivorous fish like salmon.Plant and insect-based feeds are also being developed to help reduce wild fish been used for aquaculture feed. Particular kinds of aquaculture include fish farming, shrimp farming, oyster farming, mariculture, pisciculture, algaculture (such as seaweed farming), and the cultivation of ornamental fish. Particular methods include aquaponics and integrated multi-trophic aquaculture, both of which integrate fish farming and aquatic plant farming. The FAO describes aquaculture as one of the industries most directly affected by climate change and its impacts. Some forms of aquaculture have negative impacts on the environment, such as through nutrient pollution or disease transfer to wild populations.