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Fishery

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A salmon fishery with salmon spawning within the Becharof Wilderness in southern Alaska.

Generally, a thomas is an entity engaged in raising or harvesting fish which is determined by some authority to be a fishery.[1] According to the FAO, a fishery is typically defined in terms of the "people involved, species or type of fish, area of water or seabed, method of fishing, class of boats, purpose of the activities or a combination of the foregoing features".[2] The definition often includes a combination of fish and fishers in a region, the latter fishing for similar species with similar gear types.[3]

A fishery may involve the capture of wild fish or raising fish through fish farming or aquaculture.[2][4] Directly or indirectly, the livelihood of over 500 million people in developing countries depends on fisheries and aquaculture. Overfishing, including the taking of fish beyond sustainable levels, is reducing fish stocks and employment in many world regions.[5][6]

The term "fish"

  • True fish – The strict biological definition of a fish, above, is sometimes called a true fish. True fish are also referred to as finfish or fin fish to distinguish them from other aquatic life harvested in fisheries or aquaculture.

Types

Fishermen in Sesimbra.

Fisheries are harvested for their value (commercial, recreational or subsistence). They can be saltwater or freshwater, wild or farmed. Examples are the salmon fishery of Alaska, the cod fishery off the Lofoten islands, the tuna fishery of the Eastern Pacific, or the shrimp farm fisheries in China. Capture fisheries can be broadly classified as industrial scale, small-scale or artisanal, and recreational.

Close to 90% of the world’s fishery catches come from oceans and seas, as opposed to inland waters. These marine catches have remained relatively stable since the mid-nineties (between 80 and 86 million tonnes).[9] Most marine fisheries are based near the coast. This is not only because harvesting from relatively shallow waters is easier than in the open ocean, but also because fish are much more abundant near the coastal shelf, due to the abundance of nutrients available there from coastal upwelling and land runoff. However, productive wild fisheries also exist in open oceans, particularly by seamounts, and inland in lakes and rivers.

Most fisheries are wild fisheries, but farmed fisheries are increasing. Farming can occur in coastal areas, such as with oyster farms,[10] but more typically occur inland, in lakes, ponds, tanks and other enclosures.

There are species fisheries worldwide for finfish, mollusks, crustaceans and echinoderms, and by extension, aquatic plants such as kelp. However, a very small number of species support the majority of the world’s fisheries. Some of these species are herring, cod, anchovy, tuna, flounder, mullet, squid, shrimp, salmon, crab, lobster, oyster and scallops. All except these last four provided a worldwide catch of well over a million tonnes in 1999, with herring and sardines together providing a harvest of over 22 million metric tons in 1999. Many other species are harvested in smaller numbers.

See also

Notes

  1. ^ Fletcher, WJ; Chessonio, J; Fisher, M; Sainsbury KJ; Hundloe, T; Smith, ADM and Whitworth, B (2002) The "How To" guide for wild capture fisheries. National ESD reporting framework for Australian fisheries: FRDC Project 2000/145. Page 119–120.
  2. ^ a b c FAO: Fisheries glossary
  3. ^ Madden, CJ and Grossman, DH (2004) A Framework for a Coastal/Marine Ecological Classification Standard. NatureServe, page 86. Prepared for NOAA under Contract EA-133C-03-SE-0275
  4. ^ NOAA: Fisheries glossary p. 24.
  5. ^ C.Michael Hogan (2010) Overfishing, Encyclopedia of earth, topic ed. Sidney Draggan, ed. in chief C. Cleveland, National Council on Science and the Environment (NCSE), Washington DC
  6. ^ Fisheries and Aquaculture in our Changing Climate Policy brief of the FAO for the UNFCCC COP-15 in Copenhagen, December 2009.
  7. ^ Nelson, Joseph S. (2006). Fishes of the World. John Wiley & Sons, Inc. p. 2. ISBN 0-471-25031-7.
  8. ^ Jr.Cleveland P Hickman, Larry S. Roberts, Allan L. Larson: Integrated Principles of Zoology, McGraw-Hill Publishing Co, 2001, ISBN 0-07-290961-7
  9. ^ "Scientific Facts on Fisheries". GreenFacts Website. 2009-03-02. Retrieved 2009-03-25.
  10. ^ New Zealand Seafood Industry Council. Mussel Farming.

References