Aquaculture
From Wikipedia, the free encyclopedia
Aquaculture is the cultivation of the natural produce of water (such as fish or shellfish, algae and other aquatic organisms). The term is distinguished from fishing by the idea of active human effort in maintaining or increasing the species involved, as opposed to simply taking them from the wild. Subsets of aquaculture include Mariculture (aquaculture in the ocean); Algaculture (the production of kelp/seaweed and other algae); Fish farming (the raising of catfish and tilapia in freshwater ponds or salmon in marine ponds); and the growing of cultured pearls.
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[edit] History
The practice of aquaculture is ancient and found in many cultures.
Aquaculture was used in China circa 2500 BC. When the waters lowered after river floods, some fishes, namely carps, were held in artificial lakes. Their brood were later fed using nymphs and feces from silkworms used for silk production, and they were used as a source of food protein as well as food for the hunger season. The Hawaiian people practiced aquaculture by constructing fish ponds (see Hawaiian aquaculture). A remarkable example from ancient Hawaii is the construction of a fish pond, dating from at least 1,000 years ago, at Alekoko. According to legend, it was constructed by the mythical Menehune. The Japanese practiced cultivation of seaweed by providing bamboo poles and, later, nets and oyster shells to serve as anchoring surfaces for spores.
The Romans were quite adept in breeding fish in ponds. In Europe it became common again in monasteries during the Middle Ages, since fish was scarce and thus expensive. Transportation improvements in the 19th century made fish easily available and inexpensive, even far from the seas, causing a decline in aquaculture.
Americans were rarely involved in aquaculture until the late 20th century, but California residents harvested wild kelp and made legal efforts to manage the supply starting circa 1900, later even producing it as a wartime resource. (Peter Neushul, Seaweed for War: California's World War I kelp industry, Technology and Culture 30 (July 1989), 561-583)
The current boom in aquaculture started in the 1960s as prices for fish began to climb. Wild fish capture was reaching its peak and the human population was continuing to rise. Today, commercial aquaculture exists on an unprecedented, huge scale. In the 1980s open-netcage salmon farming was also expanding; this particular type of aquaculture technology is still a minor part of the production of farmed finfish worldwide, but evidence of its negative impact on wild stocks, which started coming to light in the late 1990s, has caused it to be a major cause of controversy.[1]
[edit] Economic importance
As of 1983, (FAO Yearbook of Statistics (1983) and Aquaculture Development and Coordination Programme), aquaculture accounted for a small minority of world fish and crustacean harvests (7% and 4%), but 79% of molluscs and 75% of seaweed harvested. Modern aquaculture activity is concentrated in Asia and the Pacific, accounting for about 80% of the total harvested.
[edit] Criticism
A wide range of scientists and non-profits have raised concerns about aquaculture, particularly for its impact on the environment and on animal welfare. There are two main concerns:
First, most farmed species are carnivorous and so must be feed on other fish, usually caught in the wild. Because it takes at least two pounds of wild-caught fish (used as feed) to produce one pound of farmed fish[citation needed], environmentalists dispute claims that fish farms are more environmentally sustainable than ocean fishing. It is also claimed that most fishing is used to support fish farming rather than human consumption.
Secondly, farmed fish are kept in concentrations never seen in the wild (e.g. 50,000 fish in a two-acre area. [1]) with each fish occupying less room than the average bathtub. This can cause several forms of pollution. Packed this tightly, fish rub against each other and the sides of their cages, damaging their fins and tails and becoming sickened with various diseases and infections.[2]
On many fish farms, parasites such as sea lice are endemic. Lice damage around the head can be so severe that the bone of the living fishes' skulls can be exposed - a condition known as the 'death crown' [3] Such parasites can then attack passing wild fish, significantly affecting the wild population.
For these reasons, aquaculture operators frequently nead to use strong drugs to keep the fish alive (but many fish still die prematurely at rates of up to 30% [4]) and these drugs inevitably enter the enviroment.
The very large number of fish kept long term in a single location produces a significant amount of condensed feces, often contaminated with drugs, which again affect local waterways and their wild cousins. Finally, the farming of an alien species can lead to escapees with effects on the local wild population.
Other potential problems faced by aquaculturists are the legal hurdles of obtaining various permits and water-use rights, profitability, concerns about invasive species and genetic engineering depending on what species are involved, and interaction with the UN Law of the Sea Treaty.
[edit] References
- Hepburn, J. 2002. Taking Aquaculture Seriously. Organic Farming, Winter 2002 © Soil Association.
- Naylor, R.L., S.L. Williams, and D.R. Strong. 2001. Aquaculture – A Gateway For Exotic Species. Science, 294: 1655-6.
- The Scottish Association for Marine Science and Napier University. 2002. Review and synthesis of the environmental impacts of aquaculture
- Higginbotham James Piscinae: Artificial Fishponds in Roman Italy University of North Carolina Press (June, 1997)
- Wyban, Carol Araki (1992) Tide and Current: Fishponds of Hawai'I University of Hawaii Press :: ISBN 0-82481-396-0
[edit] External links
- American Society of Agricultural and Biological Engineers
- Aquaculture Association of Canada: Incorporated in February 1984, the AAC is a non-profit charitable organization with the goals of fostering an aquaculture industry in Canada, promoting the study of aquaculture and related sciences in Canada, gathering and disseminating information relating to aquaculture, and creating public awareness and understanding of aquaculture.
- Aqua Farm Designs - Benefits of Water recirculation systems in Aquaculture
- Fischtechnik is the worldleader in Planning and Construction of fish farms and recirculation systems
- FishingHurts.com/FishFarms: Criticism of aquaculture's effects on animal welfare and the environment
- Aquaculture Information from the Coastal Ocean Institute, Woods Hole Oceanographic Institution
- One Hour Radio Broadcast on Farmed Salmon in British Columbia, Canada - Kootenay Co-op Radio's Deconstructing Dinner program
- Aquaculture Resources Directory human selected reference links and downloadable reports, articles from numerous sources.
- FAO Fisheries Department and its SOFIA report on fisheries and aquaculture
- State of World Aquaculture – A summary for non-specialists of the above FAO report by GreenFacts.
- Organic Aquaculture: Articles and references on the merits and otherwise of farming fish organically.
- Aquaculture Knowledge Environment: A searchable online library of government and United Nations documents covering nearly every aspect of aquaculture from pond construction to international codes of conduct.
- World Aquaculture Society: Founded in 1970, the primary focus of WAS is to improve communication and information exchange within the diverse global aquaculture community.
- Natural Energy Laboratory of Hawaii Authority Learn how NELHA and its tenants are using sunshine, seawater and ingenuity to bring economic development and diversity.
- Friends of NELHA [FON] is a nonprofit corporation formed for education and outreach tours related to research, commercial and pre-commercial activities at Keahole Point, north of Kailua Kona, Hawaii.
- Watershed Watch Society Salmon farming and sea lice
- AquaNIC A comprehensive information server for aquaculture topics, including publications, news, events, job announcements, images, and related resources.
- American Fisheries Society
- New York Chapter of the American Fisheries Society
- National Oceanographic Documentation Center (NOAA)
- Read Congressional Research Service (CRS) Reports regarding Aquaculture
- A CATALOG OF THE SPECIES OF FISHES at California Academy of Sciences, Golden Gate Park, San Francisco, California.
- FISHING FOR INFORMATION HOME PAGE: Guide to on-line resources in aquaculture, fisheries and aquatic science
- Atlantic Salmon Federation an international non-profit organization which promotes the conservation and wise management of the Atlantic salmon and its environment.
- North American Lake Management Society
- Northeast Fisheries Science Center, Woods Hole, Massachusetts
- Advanced Technology Information Network (Calif Ag Tech Institute)
- CENET, the Cornell Extension NETwork
- Geographyinaction - Lough Swilly, Ireland example
- Aquaculture Resources for Ethno-Anthropologists News mirror service in the field of aquaculture with focus on his social effects
- Salmon farm in Mulroy Bay, Donegal, Ireland
- American Tilapia Association
- Aquaculture
- Aquaculture and the Protection of Wild Salmon
