AQUACULTURE'S GROWS SEEN AS CONTINUING
January 2, 2009
Improved management techniques can reduce environmental effects of the practice.
Aquaculture production of seafood will probably remain the most rapidly increasing food production system worldwide through 2025, according to an assessment published in the January 2009 issue of BioScience. The assessment, by James S. Diana of the University of Michigan at Ann Arbor, notes that despite well-publicized concerns about some harmful effects of aquaculture, the technique may, when practiced well, be no more damaging to biodiversity than other food production systems. Moreover, it may be the only way to supply growing demand for seafood as the human population increases.
Diana notes that total production from capture fisheries has remained approximately constant for the past 20 years and may decline. Aquaculture, in contrast, has increased by 8.8 percent per year since 1985 and now accounts for about one-third of all aquatic harvest by weight. Finfish, mollusks, and crustaceans dominate aquaculture production; seafood exports generate more money for developing countries than meat, coffee, tea, bananas, and rice combined.
Among the most potentially harmful effects of aquaculture, according to Diana, are the escape of farmed species that then become invasive, pollution of local waters by effluent, especially from freshwater systems, and land-use change associated with shrimp aquaculture in particular. Increased demand for fish products for use in feed and transmission of disease from captive to wild stocks are also hazards.
Nonetheless, when carefully implemented, aquaculture can reduce pressure on overexploited wild stocks, enhance depleted stocks, and boost natural production of fishes as well as species diversity, according to Diana. Some harmful effects have diminished as management techniques have improved, and aquaculture has the potential to provide much-needed employment in developing countries. Diana points to the need for thorough life-cycle analyses to compare aquaculture with other food production systems. Such analyses are, however, only now being undertaken, and more comprehensive information is needed to guide the growth of this technique in sustainable ways.
BioScience is the journal of the American Institute of Biological Sciences (AIBS) and is published jointly with the University of California Press 11 times per year. BioScience publishes commentary and peer-reviewed articles covering a wide range of biological fields, with a focus on "Organisms from Molecules to the Environment." The journal has been published since 1964. AIBS is an umbrella organization for professional scientific societies and organizations that are involved with biology. It represents some 200 member societies and organizations with a combined membership of about 250,000.