Artificial reefs are used around the world to promote fisheries They range from very simple to complex structures using a wide variety of materials to recreate some or all aspects of natural reefs, providing shelter from currents and predators, food and breeding sites for fish and other marine organisms
Japan is a world leader in Investment In fisheries, including artificial reef technology One of the more ambitious examples is a million tonne reef In deep water to cause upwelling of nutrient rich water Angling reefs, constructed by artisanal fishermen In Kerala, SW India and the sport fishing industry in Florida and Louisiana, USA, are discussed In both cases reefs were constructed to bring guaranteed fishing opportunities closer to home ports In Europe, particularly in Spain and Italy, artificial reefs have been constructed to protect valuable areas of seabed habitat from damage by trawling, whilst providing new opportunities for inshore line and fixed gear fishermen
The Southampton Reef Group has been studying an experimental concrete and cement stabilised coal ash block artificial reef In Poole Bay since 1989 and have shown that it supports the benthic stages of the lobster life cycle In areas of limited rocky habitat, provision of artificial reefs could supplement the lobster fishery The design of coastal structures (e g coastal defence, breakwaters, harbour walls) could be modified to enhance lobster (and other fish species) habitat In 1998, the Poole Bay reef was extended with concrete and scrap tyre units to determine the environmental impact of tyres in the sea
Artificial reefs have been constructed around the world to promote fisheries (Seaman and Sprague, 1991, Collins and Jensen, 1996) Materials used include asbestos, bamboo, barges, brush shelter, car bodies, coal combustion waste, concrete, driftwoode, electro-deposition, fibreglass, glass, nylon mats, oil platforms, pipe, plastic, plexiglass, pumpkin seed, PVC, resin, rice husks, rock, rubber, shells, ships, slate, solid waste, steel, tyres, wood There are a variety of reasons for reef construction, which can be classified as
creation of new habitat
restoration of damaged habitat
protection of valuable habitat
Virtually any object put into the sea seems to attract fish since many species require to be close to something This behaviour is exploited by FADS (Fish Attracting Devices), which are simple rafts or floats supporting underwater panels These aggregate fish, making them easier to catch, but do nothing to support any aspect of their life history Both natural and artificial reefs attract fish and other organisms because they provide
shelter from currents and predators,
reproduction and incubation sites plus shelter for juveniles
food supply epibiota and reef associated organisms
attachment point hard elevated substrate with access to plankton and light
Some examples of artificial reef construction around the world are discussed below to illustrate the variety of materials used and reasons for construction
Kerala, SW India, provides examples of the simplest designs of reef, constructed by village fishermen in response to loss of fishing grounds through destructive effects of trawling India
