Land-Based Recirculating Aquaculture Systems

Consumer demand for cleaner, greener, safer seafood is on the rise. Many popular fish, like tuna, cod and certain snapper are depleted in the wild from many years of poor management, overfishing and other ecological problems like pollution and damage to key habitat areas. There is a need to supplement wild-caught fish to meet consumer demand for seafood. One method to produce more fish is known broadly as aquaculture – the rearing of aquatic animals in captivity. Aquaculture is also often called “fish farming,” as it can be likened to the farming of other food animals, like chickens, pigs and cattle. Aquaculture is increasing worldwide; between 2004 and 2006 the annual growth rate of this industry was 6.1 percent in volume and 11 percent in value.

RAS can likely provide a cleaner, greener, safer alternative to open-water farms that does not compete with other ocean uses.

Widespread open-water fish farming methods, such as coastal ponds and open-ocean aquaculture (OOA), can seriously damage marine ecosystems and are far from providing the safe and sustainable seafood many consumers want. In particular, OOA – the mass production of fish in huge floating net pens or cages in open ocean waters – raises concerns about consumer safety, pollution of the marine environment and conflicts with other ocean uses.

Fortunately, RAS can likely provide a cleaner, greener, safer alternative to open-water farms that does not compete with other ocean uses. These systems are usually land-based and reuse virtually all of the water initially put into the system. As a result, RAS can reduce the discharge of waste and the need for antibiotics or chemicals used to combat disease and fish and parasite escapes – all serious concerns associated with OOA and pond aquaculture.

RAS provide a diversity of production options. Tilapia, catfish, black seabass, salmon, shrimp, clams and oysters are just a few examples of what can be raised in these systems. RAS can also be operated in tandem with aquaponics – the practice of growing plants using water rather than soil – to produce a variety of herbs, fruits and vegetables such as basil, okra, lettuce, tomatoes and melons. RAS range from small-scale urban aquaculture systems in individual homes to larger, commercial-scale farms that can produce fish and produce equaling millions of dollars in sales each year.

Currently, research and development is being conducted at academic, government and business facilities across the country to continuously improve the techniques and methods used in RAS. With innovations in waste management systems, fish feeds and energy usage, RAS has the potential to be a truly safe and sustainable aquaculture industry.

In recent years, the U.S. government has been shockingly insistent that development of open-water aquaculture, in particular ocean aquaculture, is the best way to have an increased seafood supply in the United States. Given the many ecological concerns associated with OOA, rather, the United States should be looking to explore more sustainable fish production, such as RAS. This report challenges natural resource managers and consumers to be more active in helping to promote a cleaner, greener, safer domestic seafood supply by learning more about RAS and requesting grocery stores and restaurants carry RAS products rather than those from open-water aquaculture systems.