Aquaculture of coral

Coral aquaculture, also known as coral farming or coral gardening, is the cultivation of corals for commercial purposes or coral reef restoration. Aquaculture is showing promise as a tool for restoring coral reefs, which are dying off around the world. The process protects young corals while they are most at risk of dying. Small corals are propagated in nurseries then replanted on the reef. Coral aquaculture, also known as coral farming or coral gardening, is the cultivation of corals for commercial purposes or coral reef restoration. Aquaculture is showing promise as a tool for restoring coral reefs, which are dying off around the world. The process protects young corals while they are most at risk of dying. Small corals are propagated in nurseries then replanted on the reef. Coral farmers live near the reefs they farm and work for reef conservation or for income. Coral is also farmed by scientists for research, by businesses for the live and ornamental coral trade, and by private aquarium hobbyists. Coral reef farming is the extracting of part of a coral colony or free-floating larva from a reef and growing them in a nursery until adulthood. It is commonly referred to as the 'gardening method' and has been compared to silviculture as a management practice that mimics natural ecosystems. Adult corals can be transplanted onto a reef, usually a damaged area. Coral is farmed for conservation reasons in the Philippines, Solomon Islands, Palau, Fiji, Marshall Islands and Japan. Land-based coral farming occurs in public aquariums in North America and Europe. Coral is an important foundation species. While it covers less than one percent of the ocean surface, it provides habitat for nearly one third of saltwater fish species, as well as ten percent of all fish captured for human consumption. Reefs are affected by severe weather events, such as cyclones, from predation by crown of thorns starfish and from competition for habitat with other foundation species such as seaweed. Seaweed can take over coral habitat when the water contains excess nutrients (nitrogen and phosphorus) or when fishing stocks are too low and herbivorous fish do not keep the seaweed at bay by eating it. Natural stressors to the coral reef are further aggravated by the human impact on coral reefs. Anthropogenic stressors such as runoff, coastal development, dynamite fishing, cyanide fishing, overexploitation of resources and marine pollution, put 58% percent of the world's reefs under threat as of 2009. An example is the exploitation of mushroom coral in Indonesia which is harvested for supply of the jewelry and curio trades. Harvesting of living reef organisms, including coral, is increasing around the world. Coral is often overharvested to supply growing demand. Overharvesting weakens the ability of reefs to replenish after other harmful events. Coral aquaculture/transplantation can improve coral cover, biodiversity, and structural heterogeneity of a degraded reef. Success has been achieved with fire coral, Pocillopora verrucosa and Acropora hemprichii. A restored reef hosts organisms associated with the reef, such as reef fishes. Nursery-grown coral promote reef resilience by making contributions to the larval pool. This could have a positive effect on new growth if transplanting of the new coral is made just before a larval release season.