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A fish hatchery is a "place for artificial breeding, hatching and rearing through the early life stages of animals, finfish and shellfish in particular".〔Crespi V., Coche A. (2008) Food and Agriculture Organization of the United Nations (FAO) Glossary of Aquaculture ()〕 Hatcheries produce larval and juvenile fish (and shellfish and crustaceans) primarily to support the aquaculture industry where they are transferred to on-growing systems i.e. fish farms to reach harvest size. Some species that are commonly raised in hatcheries include Pacific oysters, shrimp, Indian prawns, salmon, tilapia and scallops. The value of global aquaculture production is estimated to be US$98.4 billion in 2008 with China significantly dominating the market, however the value of aquaculture hatchery and nursery production has yet to be estimated.〔(FAO (2010) State of World Fisheries and Aquaculture )〕 Additional hatchery production for small-scale domestic uses, which is particularly prevalent in South-East Asia or for conservation programmes, has also yet to be quantified.〔〔Sim, S. Y., M. A. Rimmer, J. D. Toledo, K. Sugama, I. Rumengan, K. Williams and M. J. Phillips (2005). A guide to small-scale marine finfish hatchery technology. Australian Centre for International Agricultural Research 2005- 01 ()〕 There is much interest in supplementing exploited stocks of fish by releasing juveniles that may be wild caught and reared in nurseries before transplanting, or produced solely within a hatchery.〔Munro J.L., Bell J.D. (1997) Enhancement of marine fisheries resources Reviews in Fisheries Science 5(2): 185-222〕 Culture of finfish larvae has been utilised extensively in the United States in stock enhancement efforts to replenish natural populations.〔Lee C.S., Ostrowski A.C. (2001) Current status of marine finfish larviculture in the United States Aquaculture 200:89-109〕 The U.S. Fish and Wildlife Service have established a National Fish Hatchery System to support the conservation of native fish species.〔United States Fish and Wildlife Service: Fisheries and Habitat Conservation (2009) National Fish Hatchery System http://www.fws.gov/fisheries/nfhs/ accessed: 22/09/11〕 ==Purpose== Hatcheries produce larval and juvenile fish and shellfish for transferral to aquaculture facilities where they are ‘on-grown’ to reach harvest size. Hatchery production confers three main benefits to the industry; 1. Out of season production Consistent supply of fish from aquaculture facilities is an important market requirement.〔 Broodstock conditioning can extend the natural spawning season and thus the supply of juveniles to farms.〔〔Moretti A., Fernandex-Criado M.P., Vetillart R. (2005) Manual on Hatchery Production of Seabass and Gilthead Seabream Volume 2 FAO, Rome, 163pp. ()〕 Supply can be further guaranteed by sourcing from hatcheries in the opposite hemisphere i.e. with opposite seasons.〔(Cooper D. (2007) Perch eggs sent to Ireland NZ Aquaculture 20: 11 )〕 2. Genetic improvement Genetic modification is conducted in some hatcheries to improve the quality and yield of farmed species. Artificial fertilisation facilitates selective breeding programs which aim to improve production characteristics such as growth rate, disease resistance, survival, colour, increased fecundity and/or lower age of maturation.〔 Genetic improvement can be mediated by selective breeding, via hybridization, or other genetic manipulation techniques. 3. Reduce dependence on wild-caught juveniles In 2008 aquaculture accounted for 46% of total food fish supply, around 115 million tonnes.〔 Although wild caught juveniles are still utilised in the industry, concerns over sustainability of extracting juveniles, and the variable timing and magnitude of natural spawning events, make hatchery production an attractive alternative to support the growing demands of aquaculture.〔〔〔 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「Fish hatchery」の詳細全文を読む スポンサード リンク
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