View source for Aquaculture

{{Short description|Farming of aquatic organisms}}
{{For|the journal|Aquaculture (journal)}}
[[File:2019-03-16 01 Aquaculture in Chile.jpg|thumb|300px|Aquaculture fish farming in the fjords south of [[Castro, Chile]]]]
{{Agriculture}}

'''Aquaculture''' (less commonly spelled '''aquiculture'''),<ref name="Garner_2016">{{Citation |last=Garner |first=Bryan A. |title=Garner's Modern English Usage |year=2016 |url=http://www.lawprose.org/bryan-garner/books-by-bryan-garner/garners-modern-english-usage-4th-edition-2016 |edition=4th |publisher=Oxford University Press |isbn=978-0-19-049148-2 |author-link=Bryan A. Garner}}</ref> also known as '''aquafarming''', is the controlled cultivation ("farming") of [[aquatic organism]]s such as [[fish]], [[crustacean]]s, [[mollusk]]s, [[algae]] and other organisms of value such as [[aquatic plant]]s (e.g. [[Nelumbo nucifera|lotus]]). Aquaculture involves cultivating [[freshwater]], [[brackish water]], and [[saltwater]] populations under controlled or semi-natural conditions and can be contrasted with [[commercial fishing]], which is the harvesting of [[wild fish]].<ref name="AmericanHeritageDef">{{cite web|url=http://www.answers.com/topic/aquaculture|archive-url=https://web.archive.org/web/20060719044903/http://www.answers.com/topic/aquaculture|title=aquaculture|archive-date=2006-07-19|work=Answers.com}}</ref> Aquaculture is also a practice used for restoring and rehabilitating marine and freshwater ecosystems.<ref>{{Cite web |date=2023-02-22 |title=Study: Aquaculture can be 'part of the solution' to marine ecosystem restoration - Responsible Seafood Advocate |url=https://www.globalseafood.org/advocate/study-aquaculture-can-be-part-of-the-solution-to-marine-ecosystem-restoration/ |access-date=2024-02-17 |website=Global Seafood Alliance |language=en-US}}</ref>  [[Mariculture]], commonly known as marine farming, is aquaculture in [[seawater]] habitats and lagoons, as opposed to freshwater aquaculture. [[Pisciculture]] is a type of aquaculture that consists of fish farming to obtain [[Fish as food|fish products as food]].

Aquaculture can also be defined as the breeding, growing, and harvesting of fish and other aquatic plants, also known as farming in water. It is an environmental source of food and commercial products that help to improve healthier habitats and are used to reconstruct the population of endangered aquatic species. Technology has increased the growth of fish in coastal marine waters and open oceans due to the increased demand for seafood.<ref>{{Cite web |title=What is aquaculture? |url=https://oceanservice.noaa.gov/facts/aquaculture.html#:~:text=Aquaculture%20is%20breeding,%20raising,%20and,of%20threatened%20or%20endangered%20species. |access-date=2022-12-07 |website=National Oceanic and Atmospheric Administration, US Department of Commerce |language=EN-US}}</ref>

Aquaculture can be conducted in completely artificial facilities built on land (onshore aquaculture), as in the case of [[fish tank]], [[fish pond|pond]]s, [[aquaponics]] or [[raceway (aquaculture)|raceway]]s, where the living conditions rely on human control such as water quality (oxygen), feed or temperature. Alternatively, they can be conducted on well-sheltered shallow waters [[littoral|nearshore]] of a [[body of water]] (inshore aquaculture), where the cultivated species are subjected to relatively more naturalistic environments; or on fenced/enclosed sections of [[open ocean|open water]] away from the shore (offshore aquaculture), where the species are either cultured in cages, racks or bags and are exposed to more diverse natural conditions such as water currents (such as [[ocean current]]s), [[diel vertical migration]] and [[nutrient cycle]]s.

According to the [[Food and Agriculture Organization]] (FAO), aquaculture "is understood to mean the farming of aquatic organisms including fish, molluscs, crustaceans and aquatic plants. Farming implies some form of intervention in the [[fish hatchery|rearing process]] to enhance production, such as regular [[fish stocking|stocking]], [[fish feed|feeding]], protection from predators, etc. Farming also implies individual or corporate ownership of the stock being cultivated."<ref>[http://www.fao.org/fishery/statistics/global-aquaculture-production/en Global Aquaculture Production] Fishery Statistical Collections, FAO, Rome. Retrieved 2 October 2011.</ref> The reported output from global aquaculture operations in 2019 was over 120 million tonnes valued at&nbsp;US$274 billion, by 2022, it had risen to 130.9 million tonnes, valued at USD 312.8 billion.<ref name="TabLandArea">FAO FIGIS Database (2022) [https://www.fao.org/figis/servlet/TabLandArea?tb_ds=Aquaculture&tb_mode=TABLE&tb_act=SELECT&tb_grp=COUNTRY Global Aquaculture Production 1950–2019] {{Webarchive|url=https://web.archive.org/web/20220119053553/https://www.fao.org/figis/servlet/TabLandArea?tb_ds=Aquaculture&tb_mode=TABLE&tb_act=SELECT&tb_grp=COUNTRY |date=2022-01-19 }}. Retrieved 2 February 2022</ref><ref name="cd0683en">{{Cite book |url=https://openknowledge.fao.org/handle/20.500.14283/cd0683en |title=The State of World Fisheries and Aquaculture 2024 |date=2024-06-07 |publisher=FAO |isbn=978-92-5-138763-4 |language=en |doi=10.4060/cd0683en}}</ref> However, there are issues with the reliability of the reported figures.<ref name="overreporting" /> Further, in current aquaculture practice, products from several kilograms of wild fish are used to produce one kilogram of a [[piscivorous]] fish like [[aquaculture of salmon|salmon]].<ref name=Alliance /> Plant and insect-based feeds are also being developed to help reduce wild fish being used for aquaculture feed.

Particular kinds of aquaculture include [[fish farming]], [[shrimp farming]], [[oyster farming]], mariculture, [[pisciculture]], [[algaculture]] (such as [[seaweed farming]]), and the cultivation of [[ornamental fish]]. Particular methods include aquaponics and [[integrated multi-trophic aquaculture]], both of which integrate fish farming and aquatic plant farming. The FAO describes aquaculture as one of the industries most directly affected by climate change and its impacts.<ref>{{Cite book|url=http://www.fao.org/3/ca7166en/ca7166en.pdf |archive-url=https://ghostarchive.org/archive/20221009/http://www.fao.org/3/ca7166en/ca7166en.pdf |archive-date=2022-10-09 |url-status=live|title=FAO's work on climate change Fisheries & aquaculture 2019|publisher=[[Food and Agriculture Organization]]|year=2019}}</ref> Some forms of aquaculture have negative impacts on the environment, such as through [[nutrient pollution]] or disease transfer to wild populations.{{toclimit|3}}

==Overview==
[[File:Global capture fisheries and aquaculture production, 1990-2030.svg|thumb|right|300px|Global capture fisheries and aquaculture production reported by FAO, 1990–2030]]
[[File:World aquaculture production of food fish and aquatic plants, 1990-2016.svg|thumb|right|300px|World aquaculture production of food fish and aquatic plants, 1990–2016]]

Harvest stagnation in [[wild fisheries]] and [[overexploitation]] of popular marine species, combined with a growing demand for high-quality protein, encouraged aquaculturists to domesticate other marine species.<ref>
"'FAO: 'Fish farming is the way forward.'(Big Picture)(Food and Agriculture Administration's 'State of Fisheries and Aquaculture' report)." The Ecologist 39.4 (2009): 8–9. Gale Expanded Academic ASAP. Web. 1 October 2009. <http://find.galegroup.com/gtx/start.do?prodId=EAIM.>.</ref><ref name="uscnews.usc.edu">"[http://uscnews.usc.edu/science_technology/all_about_fish_and_oyster_farming.html The Case for Fish and Oyster Farming] {{webarchive|url=https://web.archive.org/web/20090512061109/http://uscnews.usc.edu/science_technology/all_about_fish_and_oyster_farming.html |date=2009-05-12 }}," Carl Marziali, University of Southern California Trojan Family Magazine, May 17, 2009.</ref> At the outset of modern aquaculture, many were optimistic that a "[[Blue revolution|Blue Revolution]]" could take place in aquaculture, just as the [[Green Revolution]] of the 20th century had revolutionized agriculture.<ref>"The Economist: 'The promise of a blue revolution', Aug. 7, 2003. <https://www.economist.com/special-report/2003/08/07/the-promise-of-a-blue-revolution></ref> Although land animals had long been domesticated, most seafood species were still caught from the wild. Concerned about the impact of growing demand for seafood on the world's oceans, prominent ocean explorer [[Jacques Cousteau]] wrote in 1973: "With earth's burgeoning human populations to feed, we must turn to the sea with new understanding and new technology."<ref>"Jacques Cousteau, ''The Ocean World of Jacques Cousteau: The Act of life'', World Pub: 1973."</ref>

About 430 (97%) of the species cultured {{as of|2007|lc=y}} were domesticated during the 20th and 21st centuries, of which an estimated 106 came in the decade to 2007. Given the long-term importance of agriculture,  to date, only 0.08% of known land plant species and 0.0002% of known land animal species have been domesticated, compared with 0.17% of known marine plant species and 0.13% of known marine animal species. Domestication typically involves about a decade of scientific research.<ref name="DuarteMarbaHolmer">{{cite journal|title=Rapid Domestication of Marine Species| doi=10.1126/science.1138042|pmid=17446380|volume=316|issue=5823|pages=382–383|journal=Science|year=2007|last1=Duarte|first1=C. M|last2=Marba|first2=N|last3=Holmer|first3=M|hdl=10261/89727| s2cid=84063035}}</ref> Domesticating aquatic species involves fewer risks to humans than do land animals, which took a large toll in human lives. Most major human diseases originated in domesticated animals,<ref>{{cite book
|title=Guns, Germs, and Steel
|year=2005
|publisher=[[W.W. Norton & Company, Inc.]]
|location=New York, New York
|isbn=978-0-393-06131-4
|title-link=Guns, Germs, and Steel
}}</ref> including diseases such as [[smallpox]] and [[diphtheria]], that like most infectious diseases, move to humans from animals. No human [[pathogen]]s of comparable virulence have yet emerged from marine species.<ref>{{Cite journal |last1=Lasa |first1=Aide |last2=Auguste |first2=Manon |last3=Lema |first3=Alberto |last4=Oliveri |first4=Caterina |last5=Borello |first5=Alessio |last6=Taviani |first6=Elisa |last7=Bonello |first7=Guido |last8=Doni |first8=Lapo |last9=Millard |first9=Andrew D. |last10=Bruto |first10=Maxime |last11=Romalde |first11=Jesus L. |last12=Yakimov |first12=Michail |last13=Balbi |first13=Teresa |last14=Pruzzo |first14=Carla |last15=Canesi |first15=Laura |date=September 2021 |title=A deep-sea bacterium related to coastal marine pathogens |journal=Environmental Microbiology |volume=23 |issue=9 |pages=5349–5363 |doi=10.1111/1462-2920.15629 |issn=1462-2912 |pmc=8519021 |pmid=34097814|bibcode=2021EnvMi..23.5349L }}</ref><ref>{{Cite web|url=https://www.dpi.nsw.gov.au/fishing/pests-diseases/animal-health/fish-diseases-and-human-health|title=Aquatic animal disease and human health|date=2016-04-26|website=Department of Primary Industries|access-date=October 15, 2019|archive-date=2019-11-13|archive-url=https://web.archive.org/web/20191113044257/https://www.dpi.nsw.gov.au/fishing/pests-diseases/animal-health/fish-diseases-and-human-health}}</ref>

Biological control methods to manage parasites are already being used, such as cleaner fish (e.g. lumpsuckers and wrasse) to control sea lice populations in salmon farming.<ref>{{Cite journal|title = The use of lumpfish (Cyclopterus lumpus L.) to control sea lice (Lepeophtheirus salmonis Krøyer) infestations in intensively farmed Atlantic salmon (Salmo salar L.)|journal = Aquaculture|date = 2014-03-20|pages = 18–23|volume = 424–425|doi = 10.1016/j.aquaculture.2013.12.033|first1 = Albert K.|last1 = Imsland|first2 = Patrick|last2 = Reynolds|first3 = Gerhard|last3 = Eliassen|first4 = Thor Arne|last4 = Hangstad|first5 = Atle|last5 = Foss|first6 = Erik|last6 = Vikingstad|first7 = Tor Anders|last7 = Elvegård| bibcode=2014Aquac.424...18I }}</ref> Models are being used to help with spatial planning and siting of fish farms in order to minimize impact.<ref>{{Cite web|title = DEPOMOD and AutoDEPOMOD — Ecasa Toolbox|url = http://www.ecasatoolbox.org.uk/the-toolbox/eia-species/models|website = www.ecasatoolbox.org.uk|access-date = 2015-09-24|archive-url = https://web.archive.org/web/20150925121623/http://www.ecasatoolbox.org.uk/the-toolbox/eia-species/models|archive-date = 2015-09-25}}</ref>
[[File:Aquaculture production (2023).svg|thumb|300x300px|Aquaculture production (2023)<ref>{{Cite book |url=https://doi.org/10.4060/cd4313en |title=World Food and Agriculture – Statistical Yearbook 2025 |publisher=Food and Agriculture Organization |year=2025 |isbn=978-92-5-140174-3 |language=en |doi=10.4060/cd4313en |access-date= |via=fao.org |s2cid=}}</ref>]]
The decline in wild fish stocks has increased the demand for farmed fish.<ref>{{Cite journal|title = Effect of aquaculture on world fish supplies|journal = Nature|date = 2000-06-29|issn = 0028-0836|pages = 1017–1024|volume = 405|issue = 6790|doi = 10.1038/35016500|first1 = Rosamond L.|last1 = Naylor|first2 = Rebecca J.|last2 = Goldburg|first3 = Jurgenne H.|last3 = Primavera|first4 = Nils|last4 = Kautsky|first5 = Malcolm C. M.|last5 = Beveridge|first6 = Jason|last6 = Clay|first7 = Carl|last7 = Folke|first8 = Jane|last8 = Lubchenco|first9 = Harold|last9 = Mooney|pmid=10890435|bibcode = 2000Natur.405.1017N|hdl = 10862/1737|s2cid = 4411053|hdl-access = free}}</ref> However, finding alternative sources of protein and oil for fish feed is necessary so the aquaculture industry can grow sustainably; otherwise, it represents a great risk for the over-exploitation of forage fish.<ref>{{Cite web|url = http://www.fcrn.org.uk/sites/default/files/Turning_the_tide_%20Report.pdf|title = Turning the tide|access-date = 2015-09-24|archive-date = 2016-02-22|archive-url = https://web.archive.org/web/20160222005116/http://www.fcrn.org.uk/sites/default/files/Turning_the_tide_%20Report.pdf}}</ref>

Aquaculture production now exceeds capture fishery production<ref name="ca0191en" /> and together the relative GDP contribution has ranged from 0.01 to 10%.<ref name="Cai2019">{{Cite book |last=Cai |first=Junning |title=Understanding and measuring the contribution of aquaculture and fisheries to gross domestic product (GDP) |date=2019 |others=Hui Huang, PingSun Leung |publisher=Food and Agriculture Organization of the United Nations |isbn=978-92-5-131280-3 |location=Rome |oclc=1104067293}}</ref> Singling out aquaculture's relative contribution to GDP, however, is not easily derived due to lack of data.<ref>{{Cite book|last=Food and Agriculture Organization of the United Nations|title=The state of world fisheries and aquaculture 2020: sustainability in action|date=2020|publisher=Food and Agriculture Organization of the United Nations|isbn=978-92-5-132692-3|location=Rome|oclc=1159532489}}</ref>

Another recent issue following the banning in 2008 of organotins by the International Maritime Organization is the need to find environmentally friendly, but still effective, compounds with antifouling effects.

Many new natural compounds are discovered every year, but producing them on a large enough scale for commercial purposes is almost impossible.

It is highly probable that future developments in this field will rely on microorganisms, but greater funding and further research is needed to overcome the lack of knowledge in this field.<ref>{{Cite journal|title = Qian, P. Y., Xu, Y. & Fusetani, N. Natural products as antifouling compounds: recent progress and future perspectives|url = https://www.researchgate.net/publication/40447383|journal = Biofouling|volume = 26|issue = 2|pages = 223–234|access-date = 2015-09-24|doi = 10.1080/08927010903470815|pmid = 19960389|year = 2009|last1 = Qian|first1 = Pei-Yuan|last2 = Xu|first2 = Ying|last3 = Fusetani|first3 = Nobushino|s2cid = 35932563}}</ref>

==Species groups==
{{multiple image
| align = right
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| width = 300
| header = Global aquaculture production in million tonnes, 1950–2010, as reported by the FAO<ref name="faostat">Based on data sourced from the [http://faostat.fao.org/site/629/default.aspx FishStat database] {{webarchive |url=https://web.archive.org/web/20121107001620/http://faostat.fao.org/site/629/default.aspx |date=November 7, 2012 }}</ref>
| header_align = center
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| image1 = Global aquaculture production.png
| alt1 =
| caption1 = Main species groups
| image2 = Global other aquaculture production.png
| alt2 =
| caption2 = Minor species groups
}}
[[File:World capture fisheries and aquaculture production by main producers (2018).svg|thumb|300px|World capture fisheries and aquaculture production by main producers (2018), from [[Food and Agriculture Organization|FAO]]'s Statistical Yearbook 2020<ref>{{Cite book|title=World Food and Agriculture – Statistical Yearbook 2020|publisher=FAO|year=2020|isbn=978-92-5-133394-5|location=Rome|doi=10.4060/cb1329en|s2cid=242794287}}</ref>]]

===Aquatic plants===
[[File:Yangzhuanghe - CIMG3404.JPG|thumb|300px|Cultivating emergent aquatic plants in floating containers|alt=Aquatic plants in floating containers]]
{{See also|Algaculture|Seaweed farming}}

[[Microalgae]], also referred to as [[phytoplankton]], [[microphytes]], or [[planktonic algae]], constitute the majority of cultivated [[algae]]. Macroalgae commonly known as [[seaweed]] also have many commercial and industrial uses, but due to their size and specific requirements, they are not easily cultivated on a large scale and are most often taken in the wild.

In 2016, aquaculture was the source of 96.5 percent by volume of the total 31.2 million tonnes of wild-collected and cultivated aquatic plants combined. Global production of farmed aquatic plants, overwhelmingly dominated by seaweeds, grew in output volume from 13.5 million tonnes in 1995 to just over 30 million tonnes in 2016.<ref name="ca0191en">{{Cite book|url=http://www.fao.org/3/ca0191en/ca0191en.pdf|title=In brief, The State of World Fisheries and Aquaculture, 2018|publisher=FAO|year=2018}}</ref>

====Seaweed farming====
{{Excerpt|Seaweed farming}}

===Fish===
{{Main|Fish farming}}

The farming of fish is the most common form of aquaculture. It involves raising fish commercially in tanks, [[fish pond]]s, or ocean enclosures, usually for food. A facility that releases juvenile fish into the wild for recreational fishing or to supplement a species' natural numbers is generally referred to as a fish [[hatchery]]. Worldwide, the most important fish species used in fish farming are, in order, [[carp]], [[salmon]], [[tilapia]], and [[catfish]].<ref name="faostat" />

In the Mediterranean, young [[Atlantic bluefin tuna|bluefin tuna]] are netted at sea and towed slowly towards the shore. They are then interned in [[Offshore aquaculture|offshore]] pens (sometimes made from floating HDPE pipe)<ref>{{Cite web|url=https://www.acu-tech.com.au/hdpe-pipe-products/|title=HDPE Pipe used for Aquaculture pens.|archive-url=https://web.archive.org/web/20190109111409/https://www.acu-tech.com.au/hdpe-pipe-products/|archive-date=2019-01-09}}</ref> where they are further grown for the market.<ref>{{Cite journal | doi = 10.1641/0006-3568(2005)055[0301:DWSTBF]2.0.CO;2 | author = Volpe, J. | year = 2005 | title = Dollars without sense: The bait for big-money tuna ranching around the world | journal = [[BioScience]] | volume = 55 | issue = 4| pages = 301–302 | issn = 0006-3568 | doi-access = free }}</ref> In 2009, researchers in Australia managed for the first time to coax [[southern bluefin tuna]] to breed in landlocked tanks. Southern bluefin tuna are also caught in the wild and fattened in grow-out sea cages in southern [[Spencer Gulf]], [[South Australia]].

A similar process is used in the salmon-farming section of this industry; juveniles are taken from hatcheries and a variety of methods are used to aid them in their maturation. For example, as stated above, some of the most important fish species in the industry, salmon, can be grown using a cage system. This is done by having netted cages, preferably in open water that has a strong flow, and feeding the salmon a special food mixture that aids their growth. This process allows for year-round growth of the fish, thus a higher harvest during the correct seasons.<ref>{{cite journal |title=Farming the Sea|first=Frank|last=Asche|journal=Marine Resource Economics|volume=23|issue=4|year=2008|pages=527–547 |jstor=42629678|doi=10.1086/mre.23.4.42629678|s2cid=129264961}}</ref><ref>{{cite journal |title=Future Seascapes, Fishing, and Fish Farming|first1=Rebecca |last1=Goldburg |first2=Rosamond |last2=Naylor|journal=Frontiers in Ecology and the Environment|volume=3|issue=1|date=February 2005|pages=21–28|doi=10.2307/3868441|jstor=3868441|doi-access=free}}</ref> An additional method, known sometimes as sea ranching, has also been used within the industry. Sea ranching involves raising fish in a [[hatchery]] for a brief time and then releasing them into marine waters for further development, whereupon the fish are recaptured when they have matured.<ref>{{cite book |last1=Brown |first1=E. Evan |title=World Fish Farming: Cultivation and Economics |date=1983 |publisher=AVI Publishing |location=Westport, Connecticut |isbn=978-0-87055-427-8 |page=2 |edition=Second }}</ref>

===Crustaceans===
{{See also|Shrimp farming|Freshwater prawn farming|Astaciculture}}
Commercial [[shrimp]] farming began in the 1970s, and production grew steeply thereafter. Global production reached more than 1.6 million tonnes in 2003, worth about US$9 billion. About 75% of farmed shrimp is produced in Asia, in particular in China and Thailand. The other 25% is produced mainly in Latin America, where Brazil is the largest producer. Thailand is the largest exporter.

Shrimp farming has changed from its traditional, small-scale form in Southeast Asia into a global industry. Technological advances have led to ever higher densities per unit area, and [[broodstock]] is shipped worldwide. Virtually all farmed shrimp are [[penaeid]]s (i.e., shrimp of the [[family (biology)|family]] [[Penaeidae]]), and just two species of shrimp, the [[Whiteleg shrimp|Pacific white shrimp]] and the [[giant tiger prawn]], account for about 80% of all farmed shrimp. These industrial [[monoculture]]s are very susceptible to disease, which has decimated shrimp populations across entire regions. Increasing [[ecology|ecological]] problems, repeated disease outbreaks, and pressure and criticism from both [[nongovernmental organization]]s and consumer countries led to changes in the industry in the late 1990s and generally stronger regulations. In 1999, governments, industry representatives, and environmental organizations initiated a program aimed at developing and promoting more [[sustainable agriculture|sustainable farming]] practices through the [[Seafood Watch]] program.<ref>{{cite web|title=About Seafood Watch|url=http://www.montereybayaquarium.org/cr/cr_seafoodwatch/sfw_aboutsfw.aspx?c=ln|publisher=Monterey Bay Aquarium|access-date=2013-05-30|archive-url=https://web.archive.org/web/20130511232001/http://www.montereybayaquarium.org/cr/cr_seafoodwatch/sfw_aboutsfw.aspx?c=ln|archive-date=2013-05-11}}</ref>

[[Freshwater prawn farming]] shares many characteristics with, including many problems with, marine shrimp farming. Unique problems are introduced by the developmental lifecycle of the main species, the [[giant river prawn]].<ref name="freshwater">New, M. B.: ''[http://library.enaca.org/Shrimp/Publications/FAO_Macrobrachium_manual_2003.pdf Farming Freshwater Prawns]''; FAO Fisheries Technical Paper 428, 2002. {{ISSN|0429-9345}}.</ref>

The global annual production of freshwater prawns (excluding [[crayfish]] and [[crab]]s) in 2007 was about 460,000 [[tonne]]s, exceeding 1.86 billion dollars.<ref>{{cite web |title = Freshwater Prawn Book |url = http://www.shrimpnews.com/FreeReportsFolder/FreshwaterPrawnFolder/FreshwaterPrawnsBiologyFarming.html |publisher = Wiley Blackwell |date = 2010 |access-date = November 25, 2018 |archive-date = December 1, 2018 |archive-url = https://web.archive.org/web/20181201172035/http://www.shrimpnews.com/FreeReportsFolder/FreshwaterPrawnFolder/FreshwaterPrawnsBiologyFarming.html }}</ref> Additionally, China produced about 370,000 tonnes of [[Chinese river crab]].<ref name="figis_fresh">Data extracted from the [http://www.fao.org/figis/servlet/static?dom=collection&xml=global-aquaculture-production.xml FAO Fisheries Global Aquaculture Production Database] {{Webarchive|url=https://web.archive.org/web/20050927124902/http://www.fao.org/figis/servlet/static?dom=collection&xml=global-aquaculture-production.xml |date=2005-09-27 }} for freshwater crustaceans. The most recent data are from 2003 and sometimes contain estimates. Retrieved June 28, 2005.</ref>

In addition [[astaciculture]] is the freshwater farming of crayfish (mostly in the US, Australia, and Europe).<ref>{{cite journal|doi=10.1051/alr:1993032|title=A review of astaciculture: freshwater crayfish farming|journal=Aquatic Living Resources|volume=6|issue=4|pages=307–317|year=1993|last1=Holdich|first1=David M.|bibcode=1993AqLR....6..307H |doi-access=free}}</ref>

===Molluscs===
[[File:Abalone-farm1web.jpg|thumb|300px|Abalone farm|alt=Abalone farm]]
[[File:Aquatir 0502013 11.JPG|thumb|300px|Sturgeon farm|alt=Sturgeon farm]]
{{See also|Oyster farming|Geoduck aquaculture}}

Aquacultured shellfish include various [[oyster]], [[mussel]], and clam species. These bivalves are filter and/or deposit feeders, which rely on ambient primary production rather than inputs of fish or other feed. As such, shellfish aquaculture is generally perceived as benign or even beneficial.<ref>{{cite book|doi=10.1002/9780470960967.ch7|chapter=Bivalve Shellfish Aquaculture and Eutrophication|title=Shellfish Aquaculture and the Environment|pages=155–215|year=2011|last1=Burkholder|first1=Joann M.|last2=Shumway|first2=Sandra E.|isbn=978-0-470-96096-7}}</ref>

Depending on the species and local conditions, bivalve molluscs are either grown on the beach, on longlines, or suspended from rafts and harvested by hand or by dredging. In May 2017 a Belgian consortium installed the first of two trial mussel farms on a wind farm in the [[North Sea]].<ref name="offshorewind.biz2017-06-02belgians">{{cite web
 |url=http://www.offshorewind.biz/2017/06/02/belgians-start-growing-mussels-on-offshore-wind-farms/
 | title =Belgians Start Growing Mussels on Offshore Wind Farms
 | date =June 2, 2017
 | website =offshoreWIND.biz
 | publisher =Navingo BV
 | access-date =3 June 2017
 }}</ref>

[[Abalone]] farming began in the late 1950s and early 1960s in Japan and China.<ref>{{cite web|url=http://www.fishtech.com/abaloneinfo.html| title=Abalone Farming Information| access-date=2007-11-08| archive-url= https://web.archive.org/web/20071113063321/http://www.fishtech.com/abaloneinfo.html| archive-date= 13 November 2007 |url-status= live}}</ref> Since the mid-1990s, this industry has become increasingly successful.<ref>{{cite news|url=https://www.wired.com/news/technology/0,1282,49847,00.html |title=Abalone Farming on a Boat |access-date=2007-01-27 |archive-url=https://web.archive.org/web/20070104192421/http://www.wired.com/news/technology/0%2C1282%2C49847%2C00.html |archive-date=4 January 2007 |url-status=live |magazine=Wired |date=25 January 2002 }}</ref> [[Overfishing]] and [[poaching]] have reduced wild populations to the extent that farmed abalone now supplies most abalone meat. Sustainably farmed molluscs can be certified by Seafood Watch and other organizations, including the [[World Wildlife Fund]] (WWF). WWF initiated the "Aquaculture Dialogues" in 2004 to develop measurable and performance-based standards for responsibly farmed seafood. In 2009, WWF co-founded the [[Aquaculture Stewardship Council]] with the Dutch Sustainable Trade Initiative to manage the global standards and certification programs.<ref>{{cite web|last=World Wildlife Fund|title=Sustainable Seafood, Farmed Seafood|url=http://worldwildlife.org/industries/farmed-seafood|access-date=May 30, 2013}}</ref>

After trials in 2012,<ref name="oceangrown.com.au-2013">
{{cite web
 |url         = http://www.oceangrown.com.au/wp-content/uploads/2013/10/Ocean-Grown-Information-Memorandum-Approved-Screen.pdf
 |title       = Information Memorandum, 2013 Ranching of Greenlip Abalone, Flinders Bay – Western Australia
 |website     = Ocean Grown Abalone
 |access-date = 23 April 2016
 |archive-url  = https://web.archive.org/web/20161010215256/http://www.oceangrown.com.au/wp-content/uploads/2013/10/Ocean-Grown-Information-Memorandum-Approved-Screen.pdf
 |archive-date = 10 October 2016
}}</ref> a commercial "sea ranch" was set up in [[Flinders Bay]], Western Australia, to raise abalone. The ranch is based on an artificial reef made up of 5000 ({{as of|2016|April}}) separate concrete units called ''abitats'' (abalone habitats). The 900&nbsp;kg abitats can host 400 abalone each. The reef is seeded with young abalone from an onshore hatchery. The abalone feed on seaweed that has grown naturally on the habitats, with the ecosystem enrichment of the bay also resulting in growing numbers of dhufish, pink snapper, wrasse, and Samson fish, among other species.

Brad Adams, from the company, has emphasised the similarity to wild abalone and the difference from shore-based aquaculture. "We're not aquaculture, we're ranching, because once they're in the water they look after themselves."<ref name="abc.net.au-2014-08-15">{{cite news
 | url=http://www.abc.net.au/news/2014-08-15/nrn-abalone-wild-farm/5673010
 | title =First wild abalone farm in Australia built on artificial reef
 | last =Fitzgerald
 | first =Bridget
 | date =28 August 2014
 | newspaper =ABC News
 | publisher =Australian Broadcasting Corporation
 | access-date =23 April 2016
 | quote =It's the same as the wild core product except we've got the aquaculture advantage which is consistency of supply.}}</ref><ref name="abc.net.au-2016-04-23">{{cite news
 | url=http://www.abc.net.au/news/2016-04-23/world-first-abalone-sea-ranch-creating-opportunity/7345448
 | title =Abalone grown in world-first sea ranch in WA 'as good as wild catch'
 | last =Murphy
 | first =Sean
 | date =23 April 2016
 | newspaper =ABC News
 | publisher =Australian Broadcasting Corporation
 | access-date =23 April 2016
 | quote =So to drive future growth I really believe sea ranching is a great opportunity going forward for some of these coastal communities. }}</ref>

===Other groups===
Other groups include aquatic reptiles, amphibians, and miscellaneous invertebrates, such as [[echinoderm]]s and [[jellyfish]]. They are separately graphed at the top right of this section, since they do not contribute enough volume to show clearly on the main graph.<ref>{{Cite web |title=Chapter 7: Correlation and Simple Linear Regression {{!}} Natural Resources Biometrics |url=https://courses.lumenlearning.com/suny-natural-resources-biometrics/chapter/chapter-7-correlation-and-simple-linear-regression/ |access-date=2023-10-19 |website=courses.lumenlearning.com}}</ref>

Commercially harvested echinoderms include [[sea cucumber]]s and [[sea urchin]]s. In China, sea cucumbers are farmed in artificial ponds as large as {{convert|1000|acre|ha|order=flip|abbr=off}}.<ref name="NF">{{cite web |url=http://www.nationalfisherman.com/2008.asp?ItemID=1800&pcid=373&cid=375&archive=yes |author=Ess, Charlie |title=Wild product's versatility could push price beyond $2 for Alaska dive fleet |publisher=National Fisherman |access-date=2008-08-01 |archive-url=https://web.archive.org/web/20090122074025/http://www.nationalfisherman.com/2008.asp?ItemID=1800&pcid=373&cid=375&archive=yes |archive-date=2009-01-22 }}</ref>

{{clear}}

==Global fish production==
{{Multiple image
| direction         = vertical
| image1            = World capture fisheries and aquaculture production by species group-.svg
| caption1          = By species group
| image2            = World capture fisheries and aquaculture production by main producers (2023).svg
| caption2          = By main producers (2023)
| header            = World capture fisheries and aquaculture production<ref>{{Cite book|title=World Food and Agriculture – Statistical Yearbook 2025|publisher=FAO|year=2025|isbn=978-92-5-140174-3|location=Rome}}</ref>
| total_width       = 300
}}

Global fish production peaked at about 171 million tonnes in 2016, with aquaculture representing 47 percent of the total and 53 percent if non-food uses (including reduction to fishmeal and fish oil) are excluded. With capture fishery production relatively static since the late 1980s, aquaculture has been responsible for the continuing growth in the supply of fish for human consumption.<ref name="ca0191en" /> Global aquaculture production (including aquatic plants) in 2016 was 110.2 million tonnes, with the first-sale value estimated at US$244 billion. Three years later, in 2019 the reported output from global aquaculture operations was over 120 million tonnes valued at&nbsp;US$274 billion and by 2022 it had reached 130.9 million tonnes, valued at USD 312.8 billion.<ref name="TabLandArea" /><ref name="cd0683en" /> For the first time, aquaculture surpassed capture fisheries in aquatic animal production with 94.4 million tonnes, representing 51 percent of the world total and a record 57 percent of the production destined for human consumption.<ref name="cd0683en" />

In 2022 most aquaculture workers were in Asia (95%), followed by Africa (3%) and Latin America and the Caribbean (2%).<ref name="cd0683en" />

The contribution of aquaculture to the global production of capture fisheries and aquaculture combined has risen continuously, reaching 46.8 percent in 2016, up from 25.7 percent in 2000. With 5.8 percent annual growth rate during the period 2001–2016, aquaculture continues to grow faster than other major food production sectors, but it no longer has the high annual growth rates experienced in the 1980s and 1990s.<ref name="ca0191en" />

In 2012, the total world production of fisheries was 158 million [[tonne]]s, of which aquaculture contributed 66.6 million tonnes, about 42%.<ref name="SOFIA 2014">
[[FAO]] (2014) [http://www.fao.org/3/d1eaa9a1-5a71-4e42-86c0-f2111f07de16/i3720e.pdf The State of World Fisheries and Aquaculture 2014 (SOFIA)]</ref> The growth rate of worldwide aquaculture has been sustained and rapid, averaging about 8% per year for over 30 years, while the take from wild fisheries has been essentially flat for the last decade. The aquaculture market reached $86 billion<ref>
$86 thousand million</ref> in 2009.<ref>{{cite news
|url=https://www.washingtonpost.com/wp-dyn/content/article/2010/08/01/AR2010080103305.html
|newspaper=Washington Post
|title=Company says FDA is nearing decision on genetically engineered Atlantic salmon
|first=Les |last=Blumenthal
|date=August 2, 2010 |access-date=26 November 2017}}</ref>

Aquaculture is an especially important economic activity in China. Between 1980 and 1997, the Chinese Bureau of Fisheries reports, aquaculture harvests grew at an annual rate of 16.7%, jumping from 1.9 million tonnes to nearly 23 million tonnes. In 2005, China accounted for 70% of world production.<ref>{{cite magazine|url=https://www.wired.com/wired/archive/12.05/fish.html|title=Wired 12.05: The Bluewater Revolution|magazine=wired.com|date=May 2004}}</ref><ref>{{cite news |url=https://www.washingtonpost.com/ac2/wp-dyn/A31159-2005Jan23 | newspaper=The Washington Post | title=Fish Farming's Bounty Isn't Without Barbs | first=Juliet | last=Eilperin | date=2005-01-24 | access-date=2017-08-24 | archive-date=2018-11-28 | archive-url=https://web.archive.org/web/20181128184635/https://www.washingtonpost.com/ac2/wp-dyn/A31159-2005Jan23/ }}</ref> Aquaculture is also currently one of the fastest-growing areas of food production in the U.S.<ref name="providence1">{{Cite web|url=http://www.providence.edu/polisci/students/aquaculture/EnvironmentalImpact.html|title=Environmental Impact of Aquaculture|date=August 20, 2004|archive-url=https://web.archive.org/web/20040820172559/http://www.providence.edu/polisci/students/aquaculture/EnvironmentalImpact.html|archive-date=2004-08-20}}</ref>

About 90% of all U.S. shrimp consumption is farmed and imported.<ref>{{cite web|url=http://www.fao.org/docrep/007/y5600e/y5600e00.HTM|title=The State of World Fisheries and Aquaculture|work=fao.org}}</ref> In recent years, salmon aquaculture has become a major export in southern Chile, especially in [[Puerto Montt]], Chile's fastest-growing city.

A [[Food and Agriculture Organization|United Nations]] report titled ''The State of the World Fisheries and Aquaculture'' released in May 2014 maintained fisheries and aquaculture support the livelihoods of some 60 million people in Asia and Africa.<ref name="Aquaculture2014">{{cite news|title=Fisheries and aquaculture have good future|url=http://www.heraldglobe.com/index.php/sid/222314317/scat/9d7afd9766a94f28/ht/Fisheries-and-aquaculture-have-good-future|access-date=27 May 2014|publisher=Herald Globe|archive-url=https://web.archive.org/web/20140528013244/http://www.heraldglobe.com/index.php/sid/222314317/scat/9d7afd9766a94f28/ht/Fisheries-and-aquaculture-have-good-future|archive-date=2014-05-28}}</ref> FAO estimates that in 2016, overall, women accounted for nearly 14 percent of all people directly engaged in the fisheries and aquaculture primary sector.<ref name="ca0191en" />

In 2021, global fish production reached 182 million tonnes, with approximately equal amounts coming from capture (91.2 million tonnes) and aquaculture (90.9 million tonnes). Aquaculture has experienced rapid growth in recent decades, increasing almost sevenfold from 1990 to 2021.<ref>{{Cite web |title=Life below water {{!}} SDG 14: Life below water |url=https://datatopics.worldbank.org/sdgatlas/goals/goal14 |access-date=2024-06-08 |website=Atlas of Sustainable Development Goals 2023 |language=en }}{{Dead link|date=June 2024 |bot=InternetArchiveBot |fix-attempted=yes }}</ref>

{| class="wikitable"
| data-sheets-value="{"1":2,"2":"Category"}" |'''Category'''
| data-sheets-value="{"1":3,"3":2011}" |'''2011'''
| data-sheets-value="{"1":3,"3":2012}" |'''2012'''
| data-sheets-value="{"1":3,"3":2013}" |'''2013'''
| data-sheets-value="{"1":3,"3":2014}" |'''2014'''
| data-sheets-value="{"1":3,"3":2015}" |'''2015'''
| data-sheets-value="{"1":3,"3":2016}" |'''2016'''
|-
| data-sheets-value="{"1":2,"2":"Production"}" |'''Production'''
|
|
|
|
|
|
|-
| data-sheets-value="{"1":2,"2":"Capture"}" |Capture
|
|
|
|
|
|
|-
| data-sheets-value="{"1":2,"2":"Inland"}" |Inland
| data-sheets-value="{"1":3,"3":10.7}" |10.7
| data-sheets-value="{"1":3,"3":11.2}" |11.2
| data-sheets-value="{"1":3,"3":11.2}" |11.2
| data-sheets-value="{"1":3,"3":11.3}" |11.3
| data-sheets-value="{"1":3,"3":11.4}" |11.4
| data-sheets-value="{"1":3,"3":11.6}" |11.6
|-
| data-sheets-value="{"1":2,"2":"Marine"}" |Marine
| data-sheets-value="{"1":3,"3":81.5}" |81.5
| data-sheets-value="{"1":3,"3":78.4}" |78.4
| data-sheets-value="{"1":3,"3":79.4}" |79.4
| data-sheets-value="{"1":3,"3":79.9}" |79.9
| data-sheets-value="{"1":3,"3":81.2}" |81.2
| data-sheets-value="{"1":3,"3":79.3}" |79.3
|-
| data-sheets-value="{"1":2,"2":"Total capture "}" |'''Total capture'''
| data-sheets-value="{"1":3,"3":92.2}" |'''92.2'''
| data-sheets-value="{"1":3,"3":89.5}" |'''89.5'''
| data-sheets-value="{"1":3,"3":90.6}" |'''90.6'''
| data-sheets-value="{"1":3,"3":91.2}" |'''91.2'''
| data-sheets-value="{"1":3,"3":92.7}" |'''92.7'''
| data-sheets-value="{"1":3,"3":90.9}" |'''90.9'''
|-
| data-sheets-value="{"1":2,"2":"Aquaculture"}" |Aquaculture
|
|
|
|
|
|
|-
| data-sheets-value="{"1":2,"2":"Inland"}" |Inland
| data-sheets-value="{"1":3,"3":38.6}" |38.6
| data-sheets-value="{"1":3,"3":42}" |42
| data-sheets-value="{"1":3,"3":44.8}" |44.8
| data-sheets-value="{"1":3,"3":46.9}" |46.9
| data-sheets-value="{"1":3,"3":48.6}" |48.6
| data-sheets-value="{"1":3,"3":51.4}" |51.4
|-
| data-sheets-value="{"1":2,"2":"Marine"}" |Marine
| data-sheets-value="{"1":3,"3":23.2}" |23.2
| data-sheets-value="{"1":3,"3":24.4}" |24.4
| data-sheets-value="{"1":3,"3":25.4}" |25.4
| data-sheets-value="{"1":3,"3":26.8}" |26.8
| data-sheets-value="{"1":3,"3":27.5}" |27.5
| data-sheets-value="{"1":3,"3":28.7}" |28.7
|-
| data-sheets-value="{"1":2,"2":"Total aquaculture"}" |'''Total aquaculture'''
| data-sheets-value="{"1":3,"3":61.8}" |'''61.8'''
| data-sheets-value="{"1":3,"3":66.4}" |'''66.4'''
| data-sheets-value="{"1":3,"3":70.2}" |'''70.2'''
| data-sheets-value="{"1":3,"3":73.7}" |'''73.7'''
| data-sheets-value="{"1":3,"3":76.1}" |'''76.1'''
| data-sheets-value="{"1":3,"3":80}" |'''80'''
|-
| data-sheets-value="{"1":2,"2":"Total world fisheries and aquaculture"}" |'''Total world fisheries and aquaculture'''
| data-sheets-value="{"1":3,"3":154}" |'''154'''
| data-sheets-value="{"1":3,"3":156}" |'''156'''
| data-sheets-value="{"1":3,"3":160.7}" |'''160.7'''
| data-sheets-value="{"1":3,"3":164.9}" |'''164.9'''
| data-sheets-value="{"1":3,"3":168.7}" |'''168.7'''
| data-sheets-value="{"1":3,"3":170.9}" |'''170.9'''
|-
| data-sheets-value="{"1":2,"2":"Utilization"}" |'''Utilization'''
|
|
|
|
|
|
|-
| data-sheets-value="{"1":2,"2":"Human consumption"}" |Human consumption
| data-sheets-value="{"1":3,"3":130}" |130
| data-sheets-value="{"1":3,"3":136.4}" |136.4
| data-sheets-value="{"1":3,"3":140.1}" |140.1
| data-sheets-value="{"1":3,"3":144.8}" |144.8
| data-sheets-value="{"1":3,"3":148.4}" |148.4
| data-sheets-value="{"1":3,"3":151.2}" |151.2
|-
| data-sheets-value="{"1":2,"2":"Non-food uses"}" |Non-food uses
| data-sheets-value="{"1":3,"3":24}" |24
| data-sheets-value="{"1":3,"3":19.6}" |19.6
| data-sheets-value="{"1":3,"3":20.6}" |20.6
| data-sheets-value="{"1":3,"3":20}" |20
| data-sheets-value="{"1":3,"3":20.3}" |20.3
| data-sheets-value="{"1":3,"3":19.7}" |19.7
|-
| data-sheets-value="{"1":2,"2":"Population (billions)"}" |Population (billions)
| data-sheets-value="{"1":3,"3":7}" |7
| data-sheets-value="{"1":3,"3":7.1}" |7.1
| data-sheets-value="{"1":3,"3":7.2}" |7.2
| data-sheets-value="{"1":3,"3":7.3}" |7.3
| data-sheets-value="{"1":3,"3":7.3}" |7.3
| data-sheets-value="{"1":3,"3":7.4}" |7.4
|-
| data-sheets-value="{"1":2,"2":"Per capita apparent consumption (kg)"}" |Per capita apparent consumption (kg)
| data-sheets-value="{"1":3,"3":18.5}" |18.5
| data-sheets-value="{"1":3,"3":19.2}" |19.2
| data-sheets-value="{"1":3,"3":19.5}" |19.5
| data-sheets-value="{"1":3,"3":19.9}" |19.9
| data-sheets-value="{"1":3,"3":20.2}" |20.2
| data-sheets-value="{"1":3,"3":20.3}" |20.3<ref name="ca0191en" />
|}[[File:Aquaculture production, OWID.svg|thumb|300px|Aquaculture production by region]]

===Over-reporting by China===
China overwhelmingly dominates the world in reported aquaculture output,<ref name="ChinaStats">{{cite web |url=http://www.allcountries.org/china_statistics/13_22_output_of_aquatic_products.html |title=Output of Aquatic Products |work=China Statistics |access-date=2011-04-23 }}</ref> reporting a total output which is double that of the rest of the world put together. However, there are some historical issues with the accuracy of China's returns.

In 2001, scientists Reg Watson and [[Daniel Pauly]] expressed concerns that China was over reporting its catch from wild fisheries in the 1990s.<ref name="overreporting">{{Cite journal|author1=Watson, Reg |author2=Pauly, Daniel |year=2001 |url=http://www.mindfully.org/Water/Fish-Catch-Distortions.htm |title=Systematic distortions in world Fisheries catch trends |journal=Nature |volume=414 |issue=6863 |pages=534–6 |doi=10.1038/35107050 |pmid=11734851 |archive-url=https://web.archive.org/web/20100531152626/http://www.mindfully.org/Water/Fish-Catch-Distortions.htm |archive-date=2010-05-31 |bibcode=2001Natur.414..534W |s2cid=205023890 |url-access=subscription }}</ref><ref>{{cite journal | last1 = Pearson | first1 = Helen | year = 2001 | title = China caught out as model shows net fall in fish | journal = Nature | volume = 414 | issue = 6863| page = 477 | doi = 10.1038/35107216 | pmid=11734811| bibcode = 2001Natur.414..477P | doi-access = free}}</ref> They said that made it appear that the global catch since 1988 was increasing annually by 300,000 tonnes, whereas it was really shrinking annually by 350,000 tonnes. Watson and Pauly suggested this may have been related to Chinese policies where state entities that monitored the economy were also tasked with increasing output. Also, until more recently, the promotion of Chinese officials was based on production increases from their own areas.<ref>{{cite web|last=Heilprin |first=John  |url=http://www.seaaroundus.org/OtherWebsites/2001/CaliforniaFish_29Nov01.pdf |title=Chinese Misreporting Masks Dramatic Decline In Ocean Fish Catches|publisher=Associated Press|date=29 November 2001}}</ref><ref>{{cite news|last=Reville |first=William |url=http://www.seaaroundus.org/newspapers/2002/IrishTimes_14Mar02.pdf |title=Something fishy about the figures|publisher=The Irish Times |date=14 Mar 2002}}</ref>

China disputed this claim. The official [[Xinhua News Agency]] quoted Yang Jian, director general of the Agriculture Ministry's Bureau of Fisheries, as saying that China's figures were "basically correct".<ref>[http://www.seaaroundus.org/OtherWebsites/2001/WorldCatch_17Dec01.pdf China disputes claim it over reports fish catch] ''Associated Press'', 17 December 2002.</ref> However, the FAO accepted there were issues with the reliability of China's statistical returns, and for a period treated data from China, including the aquaculture data, apart from the rest of the world.<ref>{{Cite FTP |author=FAO|authorlink=FAO |year=2006 |url=ftp://ftp.fao.org/docrep/fao/009/a0699e/a0699e.pdf |title=The State of World Fisheries and Aquaculture (SOPHIA) |access-date=2013-05-18 |server=FTP server|url-status=dead|page=5}}</ref><ref>{{Cite web|url=http://www.fao.org/3/Y3354M/Y3354M00.htm|title=FAO Fisheries Department – FISHERY STATISTICS: RELIABILITY AND POLICY IMPLICATIONS|website=www.fao.org}}</ref>

{{clear}}

==Aquacultural methods==
===Mariculture===
{{multiple image
| align             = right
| caption_align     = left
| direction         = vertical
| width             = 200
| background color  = 
| header_background = 
| header_align      = 
| header            = 
| image1            = Fish farming in High Island, Hong Kong.jpg
| alt1              = 
| caption1          = Finfish mariculture off [[High Island, Hong Kong|High Island]], Hong Kong
| image2            = Common carp.jpg
| alt2              = 
| caption2          = [[Carp]] are one of the dominant fishes in freshwater aquaculture.<ref>{{cite web|url=ftp://ftp.fao.org/FI/STAT/summary/a-6.pdf|title=FAO summary|date=April 2018|archive-url=https://web.archive.org/web/20170518134921/ftp://ftp.fao.org/FI/STAT/summary/a-6.pdf|archive-date=2017-05-18|access-date=2017-10-18}}</ref>
| image3            = Fresh tilapia.jpg
| alt3              = 
| caption3          = The adaptable [[tilapia]] is another commonly farmed freshwater fish
| footer_background = 
| footer_align      = 
| footer            = 
}}

{{Main|Mariculture}}

[[Mariculture]] is the cultivation of marine organisms in [[seawater]], variously in sheltered coastal waters ("inshore"), open ocean ("offshore"), and on land ("onshore").  Farmed species include algae (from [[microalgae]] (such as [[phytoplankton]]) to [[macroalgae]] (such as [[seaweed]]); [[shellfish]] (such as [[shrimp]]), [[lobster]], [[oyster]]s), and [[clam]]s, and [[Marine life|marine]] [[finfish]].  Channel catfish (''Ictalurus punctatus''), hard clams (''Mercenaria mercenaria'') and Atlantic salmon (''Salmo salar'') are prominent in the U.S. mariculture.<ref>{{Cite web|url=https://www.iatp.org/files/Marine_Aquaculture_in_the_United_States_Enviro.htm|title=Marine Aquaculture in the United States: Environmental Impacts and Policy Options|website=www.iatp.org|access-date=2019-07-15}}</ref>

Mariculture may consist of raising the organisms on or in artificial enclosures such as in floating netted enclosures for salmon, and on racks or in floating cages for oysters. In the case of enclosed salmon, they are fed by the operators; oysters on racks filter feed on naturally available food. Abalone have been farmed on an artificial reef consuming seaweed which grows naturally on the reef units.<ref name="abc.net.au-2016-04-23" />

===Integrated===
{{Main|Integrated multi-trophic aquaculture}}

[[Integrated multi-trophic aquaculture]] (IMTA) is a practice in which the byproducts (wastes) from one species are recycled to become inputs ([[fertilizer]]s, [[food]]) for another. Fed aquaculture (for example, [[fish]], [[shrimp]]) is combined with inorganic extractive and organic extractive (for example, [[shellfish]]) aquaculture to create balanced systems for [[environmental sustainability]] (biomitigation), economic stability (product diversification and risk reduction) and social acceptability (better management practices).<ref name="Chopin et al. 2001">{{cite journal | last1 = Chopin | first1 = T | last2 = Buschmann | first2 = AH | last3 = Halling | first3 = C | last4 = Troell | first4 = M | last5 = Kautsky | first5 = N | last6 = Neori | first6 = A | last7 = Kraemer | first7 = GP | last8 = Zertuche-Gonzalez | first8 = JA | last9 = Yarish | first9 = C | last10 = Neefus | first10 = C | year = 2001 | title = Integrating seaweeds into marine aquaculture systems: a key toward sustainability | journal = Journal of Phycology | volume = 37 | issue = 6| pages = 975–986 | doi=10.1046/j.1529-8817.2001.01137.x| bibcode = 2001JPcgy..37..975C | s2cid = 85161308}}</ref>

"Multi-trophic" refers to the incorporation of species from different [[trophic level|trophic]] or [[nutritional]] levels in the same system.<ref name="Chopin 2006">Chopin T. 2006. Integrated multi-trophic aquaculture. What it is, and why you should care&nbsp;... and don't confuse it with polyculture. Northern Aquaculture, Vol. 12, No. 4, July/August 2006, pg. 4.</ref> This is one potential distinction from the age-old practice of aquatic [[polyculture]], which could simply be the co-culture of different fish species from the same trophic level. In this case, these organisms may all share the same biological and chemical processes, with few [[synergy|synergistic]] benefits, which could potentially lead to significant shifts in the [[ecosystem]]. Some traditional polyculture systems may, in fact, incorporate a greater diversity of species, occupying several [[Ecological niche|niches]], as extensive cultures (low intensity, low management) within the same pond. A working IMTA system can result in greater total production based on mutual benefits to the co-cultured species and improved [[ecosystem health]], even if the production of individual species is lower than in a monoculture over a short-term period.<ref name="Neori et al. 2004">{{cite journal | last1 = Neori | first1 = A | last2 = Chopin | first2 = T | last3 = Troell | first3 = M | last4 = Buschmann | first4 = AH | last5 = Kraemer | first5 = GP | last6 = Halling | first6 = C | last7 = Shpigel | first7 = M | last8 = Yarish | first8 = C | year = 2004 | title = Integrated aquaculture: rationale, evolution and state of the art emphasizing seaweed biofiltration in modern mariculture | journal = Aquaculture | volume = 231 | issue = 1–4| pages = 361–391 | doi=10.1016/j.aquaculture.2003.11.015| bibcode = 2004Aquac.231..361N }}</ref>

Sometimes the term "integrated aquaculture" is used to describe the integration of monocultures through water transfer.<ref name="Neori et al. 2004" /> For all intents and purposes, however, the terms "IMTA" and "integrated aquaculture" differ only in their degree of descriptiveness. [[Aquaponics]], fractionated aquaculture, integrated agriculture-aquaculture systems, integrated peri-urban-aquaculture systems, and integrated fisheries-aquaculture systems are other variations of the IMTA concept.

=== Urban aquaculture ===
{{Excerpt|Urban aquaculture}}

==Netting materials==
Various materials, including [[nylon]], [[polyester]], [[polypropylene]], [[polyethylene]], plastic-coated welded [[wire]], [[rubber]], patented [[rope]] products (Spectra, Thorn-D, Dyneema), [[galvanized steel]] and [[copper]] are used for netting in aquaculture fish enclosures around the world.<ref>Offshore Aquaculture in the United States: Economic considerations, implications, and opportunities, U.S. Department of Commerce, National Oceanic & Atmospheric Administration, July 2008, p. 53</ref><ref name="Braithwaite">{{cite book|pmid=15596168|year=2005|last1=Braithwaite|first1=RA|last2=McEvoy|first2=LA|title=Marine biofouling on fish farms and its remediation|volume=47|pages=215–52|doi=10.1016/S0065-2881(04)47003-5|series=Advances in Marine Biology|isbn=978-0-12-026148-2}}</ref><ref>{{cite web|url=http://www.sterlingnets.com/fishfarm.html |title=Commercial and research fish farming and aquaculture netting and supplies |publisher=Sterlingnets.com |access-date=2010-06-16| archive-url= https://web.archive.org/web/20100726100545/http://www.sterlingnets.com/fishfarm.html| archive-date= 26 July 2010 |url-status= live}}</ref><ref>{{cite web |url=http://www.industrialnetting.com/aquaculture.htm |title=Aquaculture Netting by Industrial Netting |publisher=Industrialnetting.com |access-date=2010-06-16 |archive-url=https://web.archive.org/web/20100529033431/http://www.industrialnetting.com/aquaculture.htm |archive-date=2010-05-29 }}</ref><ref>Southern Regional Aquaculture Center at {{cite web |url=http://aquanic.org/publicat/usda_rac/efs/srac/162fs.pdf |title=Caged Culture |access-date=2011-08-15 |archive-url=https://web.archive.org/web/20101119190913/http://aquanic.org/publicat/usda_rac/efs/srac/162fs.pdf |archive-date=2010-11-19 }}</ref> All of these materials are selected for a variety of reasons, including design feasibility, [[material strength]], cost, and [[corrosion resistance]].

{{Main|Copper alloys in aquaculture}}

Recently, [[Copper alloys in aquaculture|copper alloys]] have become important netting materials in aquaculture because they are antimicrobial (i.e., they destroy [[bacteria]], [[viruses]], [[fungi]], [[algae]], and other [[microbes]]) and they therefore prevent [[biofouling]] (i.e., the undesirable accumulation, adhesion, and growth of microorganisms, plants, algae, tubeworms, barnacles, mollusks, and other organisms). By inhibiting microbial growth, copper alloy aquaculture cages avoid costly net changes that are necessary with other materials. The resistance of organism growth on copper alloy nets also provides a cleaner and healthier environment for farmed fish to grow and thrive.

== Technology ==
Uncrewed vessels, like [[Remotely operated underwater vehicle|ROVs]] and [[Autonomous underwater vehicle|AUVs]],  are now being used in aquaculture in various ways, such as site planning, cage or net inspection, environmental monitoring, disaster assessment, and risk reduction. The use of uncrewed vessels aims to increase safety, efficiency, and accuracy of aquaculture operations.<ref>{{Cite web |title=The Use of Uncrewed Vehicles in Coastal Aquaculture |url=https://content.ces.ncsu.edu/the-use-of-uncrewed-vehicles-in-coastal-aquaculture |access-date=2024-01-11 |website=NC State Extension Publications |language=en-US}}</ref> Aquaculture is a multi-million-dollar business that relies on net and cage maintenance. Inspections used to be conducted by divers manually inspecting the nets, but uncrewed vessels are now being used to conduct faster and more efficient inspections.<ref>{{Cite web |date=2021-06-01 |title=Contributing to Faster, More Efficient Aquaculture Cage Net Inspection with Autonomous ROV Navigation |url=https://www.ecomagazine.com/news/fisheries-aquaculture/contributing-to-faster-more-efficient-aquaculture-cage-net-inspection-with-autonomous-rov-navigation |access-date=2024-01-11 |website=ECO |language=en-gb}}</ref>

Recent advances in computer vision have further improved automated monitoring, with vision-language models capable of identifying and classifying multiple fish species in underwater environments using temporally aggregated features.<ref>{{cite journal |last1=da Silva Martins |first1=João Rodrigo |last2=Bárðarson |first2=Hlynur |last3=Guðbrandsson |first3=Jóhannes |last4=Einarsson |first4=Hafsteinn |year=2025 |title=Temporal aggregation of vision–language features for high-performance fish detection |journal=Ecological Informatics |volume=83 |article-number=102534 |doi=10.1016/j.ecoinf.2025.102534 |url=https://www.sciencedirect.com/science/article/pii/S1574954125004716}}</ref>

[[Biofloc Technology|Biofloc technology]] is also used to simultaneously improve water quality and generate bacterial biomass as food for the cultured animals.<ref>{{cite journal |last1=Bentzon-Tilia |first1=Mikkel |last2=Sonnenschein |first2=Eva C. |last3=Gram |first3=Lone |title=Monitoring and managing microbes in aquaculture – Towards a sustainable industry |journal=Microbial Biotechnology |date=September 2016 |volume=9 |issue=5 |pages=576–584 |doi=10.1111/1751-7915.12392 |pmid=27452663 |language=en |issn=1751-7915|pmc=4993175 }}</ref>

==Issues==
{{See also|Aquaculture of salmon#Issues|l1=Issues with salmon aquaculture}}
[[File:Artboard 1@3x.png|thumb]]
If performed without consideration for potential local environmental impacts, aquaculture in inland waters can result in more environmental damage than [[wild fisheries of the world|wild fisheries]], though with less waste produced per kg on a global scale.<ref>Diamond, Jared, ''Collapse: How societies choose to fail or succeed,'' Viking Press, 2005, pp.&nbsp;479–485</ref> Local concerns with aquaculture in inland waters may include waste handling, side-effects of [[antibiotic]]s, competition between farmed and wild animals, and the potential introduction of [[invasive species|invasive plant and animal species]], or foreign pathogens, particularly if unprocessed fish are used to feed more marketable [[Carnivore|carnivorous]] fish. If non-local live feeds are used, aquaculture may introduce exotic plants or animals with disastrous effects. Improvements in methods resulting from advances in research and the availability of commercial feeds has reduced some of these concerns since their greater prevalence in the 1990s and 2000s .<ref>Costa-Pierce, B.A., 2002, ''Ecological Aquaculture,'' Blackwell Science, Oxford, UK.</ref><ref>{{Cite news|url=https://www.newscientist.com/article/2112298-food-made-from-natural-gas-will-soon-feed-farm-animals-and-us/|title=Food made from natural gas will soon feed farm animals – and us|last=le Page|first=Michael|date=2016-11-10|newspaper=New Scientist|language=en-US|access-date=2016-12-12}}</ref>

Fish waste is organic and composed of nutrients necessary in all components of aquatic food webs. In-ocean aquaculture often produces much higher than normal fish waste concentrations. The waste collects on the ocean bottom, damaging or eliminating bottom-dwelling life.<ref>{{Cite news|url=http://blogs.ei.columbia.edu/2016/04/13/making-fish-farming-more-sustainable/|title=Making Fish Farming More Sustainable – State of the Planet|date=2016-04-13|work=State of the Planet|access-date=2017-12-04|language=en-US}}</ref> Waste can also decrease [[dissolved oxygen]] levels in the [[water column]], putting further pressure on wild animals.<ref>{{cite journal|doi=10.1021/es0626988|pmid=16786674|title=Fish farms harm local food supply|journal=Environmental Science & Technology|volume=40|issue=11|pages=3445–6|year=2006|last1=Thacker|first1=Paul D.|bibcode=2006EnST...40.3444T|doi-access=free}}</ref> An alternative model to food being added to the ecosystem, is the installation of artificial reef structures to increase the habitat niches available, without the need to add any more than ambient feed and nutrient. This has been used in the "ranching" of abalone in Western Australia.<ref name="abc.net.au-2016-04-23" />

===Impacts on wild fish===
Some carnivorous and omnivorous farmed fish species are fed wild [[forage fish]]. Although carnivorous farmed fish represented only 13 percent of aquaculture production by weight in 2000, they represented 34 percent of aquaculture production by value.<ref>{{cite web|author=FAO|author-link=FAO|url=http://www.fao.org/3/a-y4490e/y4490E01.pdf |title=Aquaculture Production Trends Analysis |year=2000}}</ref>

Farming of carnivorous species like salmon and shrimp leads to a high demand for forage fish to match the nutrition they get in the wild. Fish do not actually produce [[omega-3 fatty acid]]s, but instead accumulate them from either consuming [[microalgae]] that produce these fatty acids, as is the case with forage fish like [[herring]] and [[sardine]]s, or, as is the case with fatty [[predatory fish]], like salmon, by eating [[prey fish]] that have accumulated omega-3 fatty acids from microalgae. To satisfy this requirement, more than 50 percent of the world [[fish oil]] production is fed to farmed salmon.<ref>{{Cite FTP |author=FAO|authorlink=FAO |title=World Review of Fisheries and Aquaculture Highlights of Special Studies |url=ftp://ftp.fao.org/docrep/fao/011/i0250e/i0250e03.pdf |server=FTP server|url-status=dead|date=August 2018 }}</ref>

Farmed salmon consume more [[wild fish]] than they generate as a final product, although the efficiency of production is improving. To produce one kilograms of farmed salmon, products from several kilograms of wild fish are fed to them – this can be described as the "fish-in-fish-out" (FIFO) ratio. In 1995, salmon had a FIFO ratio of 7.5 (meaning 7.5 kilograms of wild fish feed were required to produce one kilogram of salmon); by 2006 the ratio had fallen to 4.9.<ref>{{cite journal | last1 = Tacon | last2 = Metian | year = 2008 | title = Global overview on the use of fish meal and fish oil in industrially compounded aquafeeds: Trends and future prospects |url=http://www.nmfs.noaa.gov/aquaculture/docs/feeds/tacon_etal_global_fishmealoil_overview_2008.pdf | journal = Aquaculture | volume = 285 | issue = 1–4| pages = 146–158 | doi=10.1016/j.aquaculture.2008.08.015| bibcode = 2008Aquac.285..146T }}</ref> Additionally, a growing share of fish oil and fishmeal come from residues (byproducts of fish processing), rather than dedicated whole fish.<ref>{{Cite web|last=Urbina|first=Ian|title=The Bane of Unsustainable Fishing.|url=https://www.safinacenter.org/blog/the-bane-of-unsustainable-fishing|website=The Safina Center|date=19 June 2020 }}</ref> In 2012, 34 percent of fish oil and 28 percent of fishmeal came from residues.<ref>{{cite web |url=http://www.keepeek.com/Digital-Asset-Management/oecd/agriculture-and-food/oecd-fao-agricultural-outlook-2014_agr_outlook-2014-en#page191 |title=OECD-FAO Agricultural Outlook |year=2014 |publisher=OECD |access-date=2015-09-24 |archive-date=2015-09-25 |archive-url=https://web.archive.org/web/20150925122543/http://www.keepeek.com/Digital-Asset-Management/oecd/agriculture-and-food/oecd-fao-agricultural-outlook-2014_agr_outlook-2014-en#page191 }}</ref> However, fishmeal and oil from residues instead of whole fish have a different composition with more ash and less protein, which may limit its potential use for aquaculture.

As the salmon farming industry expands, it requires more wild forage fish for feed, at a time when seventy-five percent of the world's monitored fisheries are already near to or have exceeded their [[maximum sustainable yield]].<ref name=Alliance>[[Seafood Choices Alliance]] (2005) {{usurped|1=[https://web.archive.org/web/20150924095748/http://www.seafoodchoices.com/resources/afishianado_pdfs/Salmon_Spring05.pdf It's all about salmon]}}</ref> The industrial-scale extraction of wild forage fish for salmon farming then impacts the survivability of the wild predator fish who rely on them for food. An important step in reducing the impact of aquaculture on wild fish is shifting carnivorous species to plant-based feeds. Salmon feeds, for example, have gone from containing only fishmeal and oil to containing 40 percent plant protein.<ref>{{cite journal | last1 = Torrissen |display-authors=et al | year = 2011 | title = Atlantic Salmon (Salmo salar): The "Super-Chicken" of the Sea? | journal = Reviews in Fisheries Science | volume = 19 | issue = 3| page = 3 | doi=10.1080/10641262.2011.597890|bibcode=2011RvFS...19..257T |s2cid=58944349 }}</ref> The USDA has also experimented with using grain-based feeds for farmed [[trout]].<ref>{{cite web|url=https://www.ars.usda.gov/pacific-west-area/aberdeen-id/small-grains-and-potato-germplasm-research/docs/fish-new/|title=USDA Grains Project|publisher=USDA ARS}}</ref> When properly formulated (and often mixed with fishmeal or oil), plant-based feeds can provide proper nutrition and similar growth rates in carnivorous farmed fish.<ref>NOAA/USDA: [http://www.nmfs.noaa.gov/aquaculture/docs/feeds/the_future_of_aquafeeds_final.pdf The Future of Aquafeeds] (2011)</ref>

Another impact aquaculture production can have on wild fish is the risk of fish escaping from coastal pens, where they can interbreed with their wild counterparts, diluting wild genetic stocks.<ref>{{cite web|url=http://www.davidsuzuki.org/Oceans/Aquaculture/Salmon/|archive-url=http://arquivo.pt/wayback/20160515132005/http://www.davidsuzuki.org/Oceans/Aquaculture/Salmon/|archive-date=2016-05-15|title=Oceans|work=davidsuzuki.org}}</ref> Escaped fish can become [[invasive species|invasive]], out-competing native species.<ref>
"[http://find.galegroup.com/gtx/start.do?prodId=EAIM Aquaculture's growth continuing: improved management techniques can reduce environmental effects of the practice. (UPDATE).]" Resource: Engineering & Technology for a Sustainable World 16.5 (2009): 20–22. Gale Expanded Academic ASAP. Web. 1 October 2009.</ref><ref>{{Cite journal
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===Animal welfare===
{{See also|Pain in fish|Pain in invertebrates}}
As with the farming of terrestrial animals, social attitudes influence the need for humane practices and regulations in farmed marine animals. Under the guidelines advised by the [[Farm Animal Welfare Council]] good animal welfare means both fitness and a sense of well-being in the animal's physical and mental state. This can be defined by the [[Five Freedoms]]:
* Freedom from hunger and thirst
* Freedom from discomfort
* Freedom from pain, disease, or injury
* Freedom to express normal behaviour
* Freedom from fear and distress

However, the controversial issue in aquaculture is whether fish and farmed marine invertebrates are actually [[Sentience|sentient]], or have the perception and awareness to experience suffering. Although no evidence of this has been found in marine invertebrates,<ref name="Hastein">{{cite journal|last1=Håstein|first1=T.|last2=Scarfe|first2=A. D.|last3=Lund|first3=V. L.|year=2005|title=Science-based assessment of welfare: Aquatic animals|journal=Revue Scientifique et Technique (International Office of Epizootics)|volume=24|issue=2|pages=529–47|doi=10.20506/rst.24.2.1590|pmid=16358506|doi-access=free}}</ref> recent studies conclude that fish do have the necessary receptors ([[nociceptors]]) to sense noxious stimuli and so are likely to experience states of pain, fear and stress.<ref name="Hastein" /><ref>{{cite journal|last1=Chandroo|first1=K.P|last2=Duncan|first2=I.J.H|last3=Moccia|first3=R.D|year=2004|title=Can fish suffer?: Perspectives on sentience, pain, fear and stress|journal=Applied Animal Behaviour Science|volume=86|issue=3–4|pages=225–250|doi=10.1016/j.applanim.2004.02.004}}</ref> Consequently, welfare in aquaculture is directed at vertebrates, finfish in particular.<ref name="Conte">{{cite journal|last1=Conte|first1=F.S.|year=2004|title=Stress and the welfare of cultured fish|journal=Applied Animal Behaviour Science|volume=86|issue=3–4|pages=205–223|doi=10.1016/j.applanim.2004.02.003}}</ref>

====Common welfare concerns====
Welfare in aquaculture can be impacted by a number of issues such as stocking densities, behavioural interactions, [[fish diseases and parasites#Disease|disease]] and [[fish diseases and parasites#Parasites|parasitism]]. A major problem in determining the cause of impaired welfare is that these issues are often all interrelated and influence each other at different times.<ref name="Huntingford">{{Cite journal|last1=Huntingford|first1=F. A.|last2=Adams|first2=C.|last3=Braithwaite|first3=V. A.|last4=Kadri|first4=S.|last5=Pottinger|first5=T. G.|last6=Sandoe|first6=P.|last7=Turnbull|first7=J. F.|year=2006|title=Current issues in fish welfare|url=http://cognition.icapb.ed.ac.uk/resources/pdf/jfbwelfare06.pdf|journal=Journal of Fish Biology|volume=68|issue=2|pages=332–372|doi=10.1111/j.0022-1112.2006.001046.x|bibcode=2006JFBio..68..332H |s2cid=84511123 |archive-url=https://web.archive.org/web/20120426045124/http://cognition.icapb.ed.ac.uk/resources/pdf/jfbwelfare06.pdf|archive-date=2012-04-26|access-date=2011-12-12}}<!-- also here: http://www.senasa.gov.ar/Archivos/File/File3393-huntingford2006.pdf --></ref>

Optimal stocking density is often defined by the [[carrying capacity]] of the stocked environment and the amount of individual space needed by the fish, which is very species specific. Although behavioural interactions such as [[shoaling and schooling|shoaling]] may mean that high stocking densities are beneficial to some species,<ref name="Hastein" /><ref name=Ashley>{{cite journal|last1=Ashley|first1=Paul J.|year=2007|title=Fish welfare: Current issues in aquaculture|journal=Applied Animal Behaviour Science|volume=104|issue=3–4|pages=199–235|doi=10.1016/j.applanim.2006.09.001}}</ref> in many cultured species high stocking densities may be of concern. Crowding can constrain normal swimming behaviour, as well as increase aggressive and competitive behaviours such as cannibalism,<ref>{{cite journal|vauthors=Baras E, Jobling M|year=2002|title=Dynamics of intracohort cannibalism in cultured fish|journal=Aquaculture Research|volume=33|issue=7|pages=461–479|doi=10.1046/j.1365-2109.2002.00732.x|doi-access=free}}</ref> feed competition,<ref>{{cite journal|author1=Greaves K.|author2=Tuene S.|year=2001|title=The form and context of aggressive behaviour in farmed Atlantic halibut (Hippoglossus hippoglossus L.)|journal=Aquaculture|volume=193|issue=1–2|pages=139–147|doi=10.1016/S0044-8486(00)00476-2|bibcode=2001Aquac.193..139G }}</ref> territoriality and dominance/subordination hierarchies.<ref name="Ellis">{{cite journal|author1=Ellis T.|author2=North B.|author3=Scott A.P.|author4=Bromage N.R.|author5=Porter M.|author6=Gadd D.|year=2002|title=The relationships between stocking density and welfare in farmed rainbow trout|journal=Journal of Fish Biology|volume=61|issue=3|pages=493–531|doi=10.1111/j.1095-8649.2002.tb00893.x|bibcode=2002JFBio..61..493E }}</ref> This potentially increases the risk of tissue damage due to abrasion from fish-to-fish contact or fish-to-cage contact.<ref name="Hastein" /> Fish can suffer reductions in food intake and [[feed conversion ratio|food conversion efficiency]].<ref name="Ellis" /> In addition, high stocking densities can result in water flow being insufficient, creating inadequate oxygen supply and waste product removal.<ref name=Ashley /> [[Dissolved oxygen]] is essential for fish respiration and concentrations below critical levels can induce stress and even lead to [[asphyxiation]].<ref name="Ellis" /> Ammonia, a nitrogen excretion product, is highly toxic to fish at accumulated levels, particularly when oxygen concentrations are low.<ref>{{cite journal|author1=Remen M.|author2=Imsland A.K.|author3=Steffansson S.O.|author4=Jonassen T.M.|author5=Foss A.|year=2008|title=Interactive effects of ammonia and oxygen on growth and physiological status of juvenile Atlantic cod (''Gadus morhua'')|journal=Aquaculture|volume=274|issue=2–4|pages=292–299|doi=10.1016/j.aquaculture.2007.11.032|bibcode=2008Aquac.274..292R }}</ref>

Many of these interactions and effects cause stress in the fish, which can be a major factor in facilitating fish disease.<ref name="Conte" /> For many parasites, infestation depends on the host's degree of mobility, the density of the host population and vulnerability of the host's defence system.<ref>{{cite journal|author=Paperna I|year=1991|title=Diseases caused by parasites in the aquaculture of warm water fish|journal=Annual Review of Fish Diseases|volume=1|pages=155–194|doi=10.1016/0959-8030(91)90028-I}}</ref> Sea lice are the primary parasitic problem for finfish in aquaculture, high numbers causing widespread skin erosion and haemorrhaging, gill congestion, and increased mucus production.<ref>{{cite journal|author1=Johnson S.C.|author2=Treasurer J.W.|author3=Bravo S.|author4=Nagasawa K.|author5=Kabata Z.|year=2004|title=A review of the impact of parasitic copepods on marine aquaculture|journal=Zoological Studies|volume=43|issue=2|pages=229–243}}</ref> There are also a number of prominent viral and bacterial [[pathogen]]s that can have severe effects on internal organs and nervous systems.<ref>{{cite journal|author1=Johansen L.H.|author2=Jensen I.|author3=Mikkelsen H.|author4=Bjorn P.A.|author5=Jansen P.A.|author6=Bergh O.|year=2011|title=Disease interaction and pathogens exchange between wild and farmed fish populations with special reference to Norway|url=https://brage.bibsys.no/xmlui/bitstream/11250/108947/1/Aquacult_315_3-4_2011_167-186.pdf |archive-url=https://ghostarchive.org/archive/20221009/https://brage.bibsys.no/xmlui/bitstream/11250/108947/1/Aquacult_315_3-4_2011_167-186.pdf |archive-date=2022-10-09 |url-status=live|journal=Aquaculture|volume=315|issue=3–4|pages=167–186|doi=10.1016/j.aquaculture.2011.02.014|bibcode=2011Aquac.315..167J |hdl=11250/117164|hdl-access=free}}</ref>

====Improving welfare====
The key to improving welfare of marine cultured organisms is to reduce stress to a minimum, as prolonged or repeated stress can cause a range of adverse effects. Attempts to minimise stress can occur throughout the culture process. Understanding and providing required environmental enrichment can be vital for reducing stress and benefit aquaculture objects such as improved growth body condition and reduced damage from aggression.<ref>{{cite journal|last1=Jones|first1=N.A.R.|last2=Webster|first2=M.|last3=Salvanes|first3=A.G.V.|year=2021|title=Physical enrichment research for captive fish: Time to focus on the DETAILS |url=https://onlinelibrary.wiley.com/doi/full/10.1111/jfb.14773|journal=Journal of Fish Biology|volume=99|issue=3|pages=704–725|doi=10.1111/jfb.14773|pmid=33942889|bibcode=2021JFBio..99..704J |hdl=10023/23362|s2cid=233719781|hdl-access=free}}</ref> During grow-out it is important to keep stocking densities at appropriate levels specific to each species, as well as separating size classes and grading to reduce aggressive behavioural interactions. Keeping nets and cages clean can assist positive water flow to reduce the risk of water degradation.

Not surprisingly disease and parasitism can have a major effect on fish welfare and it is important for farmers not only to manage infected stock but also to apply disease prevention measures. However, prevention methods, such as vaccination, can also induce stress because of the extra handling and injection.<ref name=Ashley /> Other methods include adding antibiotics to feed, adding chemicals into water for treatment baths and biological control, such as using [[cleaner fish|cleaner wrasse]] to remove lice from farmed salmon.<ref name=Ashley />

Many steps are involved in transport, including capture, food deprivation to reduce faecal contamination of transport water, transfer to transport vehicle via nets or pumps, plus transport and transfer to the delivery location. During transport water needs to be maintained to a high quality, with regulated temperature, sufficient oxygen and minimal waste products.<ref name="Conte" /><ref name=Ashley /> In some cases [[anaesthetics]] may be used in small doses to calm fish before transport.<ref name=Ashley />

Aquaculture is sometimes part of an environmental rehabilitation program or as an aid in conserving endangered species.<ref>{{cite book|author=Food and Agriculture Organization of the United Nations|url=https://books.google.com/books?id=mZ0eOg8ld5QC&q=aquaculture%20and%20rehabilitation%20and%20ex-situ&pg=PA25|title=Aquaculture Development|via=google.be|year=1997|publisher=Food & Agriculture Org. |isbn=978-92-5-103971-7}}</ref>

===Coastal ecosystems===
Aquaculture is becoming a significant threat to [[Aquatic ecosystem|coastal ecosystems]]. About 20 percent of mangrove forests have been destroyed since 1980, partly due to [[shrimp farm]]ing.<ref name="autogenerated1">{{Cite journal | doi = 10.1016/S0921-8009(98)00044-5 | last1 = Nickerson | first1 = DJ | year = 1999 | title = Trade-offs of mangrove area development in the Philippines | journal = Ecol. Econ. | volume = 28 | issue = 2| pages = 279–298 }}</ref> An [[extended cost]]–benefit analysis of the [[Total Economic Value|total economic value]] of shrimp aquaculture built on mangrove ecosystems found that the [[Externality|external]] costs were much higher than the external benefits.<ref>{{Cite journal | doi = 10.1007/s00267-003-0286-9 | pmid = 16151655 | last1 = Gunawardena | first1 = M | last2 = Rowan | first2 = JS | year = 2005 | title = Economic Valuation of a Mangrove Ecosystem Threatened by Shrimp Aquaculture in Sri Lanka | journal = Journal of Environmental Management | volume = 36 | issue = 4| pages = 535–550| bibcode = 2005EnMan..36..535G | s2cid = 27718582}}</ref> Over four decades, {{convert|269000|ha}} of Indonesian mangroves have been converted to shrimp farms. Most of these farms are abandoned within a decade because of the [[toxin]] build-up and [[nutrient]] loss.<ref>{{cite book|first=Don |last=Hinrichsen|title=Coastal Waters of the World: Trends, Threats, and Strategies|url={{google books |plainurl=y |id=fQy8BwAAQBAJ}}|date=1 February 1999|publisher=Island Press|isbn=978-1-55963-383-3}}</ref><ref>[http://atlas.aaas.org/index.php?part=2&sec=natres&sub=meatfish Meat and Fish] {{Webarchive|url=https://web.archive.org/web/20110624030256/http://atlas.aaas.org/index.php?part=2&sec=natres&sub=meatfish |date=2011-06-24}} [[American Association for the Advancement of Science]] Atlas of Population and Environment. Retrieved 4 January 2010.</ref>

====Pollution from sea cage aquaculture====
[[File:Salmon aquaculture in Norway.jpg|thumb|Salmon aquaculture, Norway]]
[[Aquaculture of salmon|Salmon farms]] are typically sited in pristine coastal ecosystems which they then pollute. A farm with 200,000 salmon discharges more fecal waste than a city of 60,000 people. This waste is discharged directly into the surrounding aquatic environment, untreated, often containing antibiotics and [[pesticide]]s."<ref name=Alliance /> There is also an accumulation of [[heavy metals]] on the [[benthos]] (seafloor) near the salmon farms, particularly [[copper]] and [[zinc]].<ref name="FAO coho">
{{cite web|author=FAO |url=http://www.fao.org/fishery/culturedspecies/Oncorhynchus_kisutch/en |title=Cultured Aquatic Species Information Programme ''Oncorhynchus kisutch'' (Walbaum, 1792)|access-date= 8 May 2009}}</ref>

In 2016, mass fish kill events impacted salmon farmers along Chile's coast and the wider ecology.<ref>{{Cite news|url=https://www.theguardian.com/environment/2016/mar/10/chiles-salmon-farms-lose-800m-as-algal-bloom-kills-millions-of-fish|title=Chile's salmon farms lose $800m as algal bloom kills millions of fish|agency=Reuters|date=2016-03-10|newspaper=The Guardian|access-date=2016-05-07}}</ref> Increases in aquaculture production and its associated effluent were considered to be possible contributing factors to fish and molluscan mortality.<ref>{{Cite news|url=http://www.abc.net.au/news/2016-05-04/wave-of-dead-sea-creatures-hits-chile-beaches/7384576|title=Wave of dead sea creatures hits Chile's beaches|date=2016-05-04|website=ABC News|language=en-AU|access-date=2016-05-07}}</ref>

Sea cage aquaculture is responsible for nutrient enrichment of the waters in which they are established. This results from fish wastes and uneaten feed inputs. Elements of most concern are nitrogen and phosphorus which can promote algal growth, including harmful algal blooms which can be toxic to fish. Flushing times, current speeds, distance from the shore and water depth are important considerations when locating sea cages in order to minimize the impacts of nutrient enrichment on coastal ecosystems.

The extent of the effects of pollution from sea-cage aquaculture varies depending on where the cages are located, which species are kept, how densely cages are stocked and what the fish are fed. Important species-specific variables include the species' food conversion ratio (FCR) and nitrogen retention.

===Freshwater ecosystems===
Whole-lake experiments carried out at the [[Experimental Lakes Area]] in Ontario, Canada, have displayed the potential for cage aquaculture to source numerous changes in freshwater ecosystems. Following the initiation of an experimental [[rainbow trout]] cage farm in a small [[Boreal ecosystem|boreal]] lake, dramatic reductions in [[mysis]] concentrations associated with a decrease in dissolved oxygen were observed.<ref>{{Cite journal|last1=Paterson|first1=Michael J.|last2=Podemski|first2=Cheryl L.|last3=Findlay|first3=Wilhelmina J.|last4=Findlay|first4=David L.|last5=Salki|first5=Alex G.|date=2010-11-03|editor-last=Sprules|editor-first=Gary|title=The response of zooplankton in a whole-lake experiment on the effects of a cage aquaculture operation for rainbow trout (Oncorhynchus mykiss)|journal=Canadian Journal of Fisheries and Aquatic Sciences|language=en|volume=67|issue=11|pages=1852–1861|doi=10.1139/F10-106|bibcode=2010CJFAS..67.1852P |issn=0706-652X}}</ref> Significant increases in ammonium and total phosphorus, a driver for [[eutrophication]] in freshwater systems,<ref>{{Cite journal|last=Schindler|first=D. W.|date=1974-05-24|title=Eutrophication and Recovery in Experimental Lakes: Implications for Lake Management |journal=Science|volume=184|issue=4139|pages=897–899|doi=10.1126/science.184.4139.897 |pmid=17782381|bibcode=1974Sci...184..897S|s2cid=25620329|issn=0036-8075}}</ref> were measured in the [[hypolimnion]] of the lake. Annual phosphorus inputs from aquaculture waste exceeded that of natural inputs from atmospheric deposition and inflows,<ref>{{Cite journal|last1=Bristow|first1=Corben E.|last2=Morin|first2=Antoine|last3=Hesslein|first3=Ray H.|last4=Podemski|first4=Cheryl L.|date=2008-11-04|title=Phosphorus budget and productivity of an experimental lake during the initial three years of cage aquaculture|journal=Canadian Journal of Fisheries and Aquatic Sciences|volume=65|issue=11|pages=2485–2495|doi=10.1139/f08-155|bibcode=2008CJFAS..65.2485B |issn=0706-652X}}</ref> and phytoplankton biomass has had a fourfold annual increase following the initiation of the experimental farm.<ref>{{Cite journal|last1=Findlay|first1=David L.|last2=Podemski|first2=Cheryl L.|last3=Kasian|first3=Susan E.M.|date=2009-10-21|editor-last=Smith|editor-first=Ralph|title=Aquaculture impacts on the algal and bacterial communities in a small boreal forest lakeThis paper is part of the series "Forty Years of Aquatic Research at the Experimental Lakes Area".|journal=Canadian Journal of Fisheries and Aquatic Sciences|language=en|volume=66|issue=11|pages=1936–1948|doi=10.1139/F09-121|bibcode=2009CJFAS..66.1936F |issn=0706-652X}}</ref>

===Genetic modification===
A type of salmon called the AquAdvantage salmon has been [[Genetically modified organism|genetically modified]] for faster growth, although it has not been approved for commercial use, due to controversy.<ref>Mcleod C, J Grice, H Campbell and T Herleth (2006) [http://www.conversations.canterbury.ac.nz/documents/Salmon%20Report.pdf Super Salmon: The Industrialisation of Fish Farming and the Drive Towards GM Technologies in Salmon Production] {{Webarchive|url=https://web.archive.org/web/20130505015144/http://www.conversations.canterbury.ac.nz/documents/Salmon%20Report.pdf |date=2013-05-05 }} CSaFe, Discussion paper 5, [[University of Otago]].</ref> The altered salmon incorporates a growth hormone from a [[Chinook salmon]] that allows it to reach full size in 16–28 months, instead of the normal 36 months for Atlantic salmon, and while consuming 25 percent less feed.<ref>Robynne Boyd, [http://blogs.scientificamerican.com/plugged-in/would-you-eat-aquadvantage-salmon-if-approved/ Would you eat AquAdvantage salmon if approved?] ''Scientific American'' online, 26 April 2013.</ref> The U.S. Food and Drug Administration reviewed the AquAdvantage salmon in a draft environmental assessment and determined that it "would not have a significant impact (FONSI) on the U.S. environment."<ref>FDA: [https://web.archive.org/web/20121231004929/http://www.fda.gov/AnimalVeterinary/DevelopmentApprovalProcess/GeneticEngineering/GeneticallyEngineeredAnimals/ucm280853.htm AquAdvantage Salmon]</ref><ref>{{Cite book|last1=Black|first1=K. D.|title=Encyclopedia of Ocean Sciences|publisher=Academic Press|year=2001|isbn=978-0-12-227430-5|editor=Steele, John H.|pages=[https://archive.org/details/encyclopediaofoc0000unse/page/1578 1578–84]|chapter=Mariculture, Environmental, Economic and Social Impacts of|doi=10.1006/rwos.2001.0487|editor2=Thorpe, Steve A.|editor3=Turekian, Karl K.|chapter-url=https://archive.org/details/encyclopediaofoc0000unse/page/1578}}</ref>

===Fish diseases, parasites and vaccines===
A major difficulty for aquaculture is the tendency towards monoculture and the associated risk of widespread [[Fish diseases and parasites|disease]]. Aquaculture is also associated with environmental risks; for instance, [[shrimp farm]]ing has caused the destruction of important [[mangrove forest]]s throughout [[southeast Asia]].<ref>{{Cite book| editor = Steele, John H.| editor2 = Thorpe, Steve A.| editor3 = Turekian, Karl K.| publisher = Academic Press| doi = 10.1006/rwos.2001.0487| chapter = Mariculture, Environmental, Economic and Social Impacts of| title = Encyclopedia of Ocean Sciences| pages = [https://archive.org/details/encyclopediaofoc0000unse/page/1578 1578–84]| year = 2001| last1 = Black| first1 = K. D.| isbn = 978-0-12-227430-5| chapter-url = https://archive.org/details/encyclopediaofoc0000unse/page/1578}}</ref>

In the 1990s, disease wiped out China's farmed [[Farrer's scallop]] and [[Chinese white shrimp|white shrimp]] and required their replacement by other species.<ref>"[http://china.nlambassade.org/binaries/content/assets/postenweb/c/china/zaken-doen-in-china/import/kansen_en_sectoren/agrofood/rapporten_over_agro_food/an-overview-of-chinas-aquaculture An Overview of China's Aquaculture]", page 6. Netherlands Business Support Office (Dalian), 2010.</ref>

====Needs of the aquaculture sector in vaccines====
Aquaculture has an average annual growth rate of 9.2%, however, the success and continued expansion of the fish farming sector is highly dependent on the control of fish pathogens including a wide range of viruses, bacteria, fungi, and parasites. In 2014, it was estimated that these parasites cost the global salmon farming industry up to 400 million Euros. This represents 6–10% of the production value of the affected countries, but it can go up to 20% (Fisheries and Oceans Canada, 2014). Since pathogens quickly spread within a population of cultured fish, their control is vital for the sector.
Historically, the use of antibiotics was against bacterial epizootics but the production of animal proteins has to be sustainable, which means that preventive measures that are acceptable from a biological and environmental point of view should be used to keep disease problems in aquaculture at an acceptable level. So, this added to the efficiency of vaccines resulted in an immediate and permanent reduction in the use of antibiotics in the 90s. In the beginning, there were fish immersion vaccines efficient against the vibriosis but proved ineffective against the furunculosis, hence the arrival of injectable vaccines: first water-based and after oil-based, much more efficient (Sommerset, 2005).

====Development of new vaccines====
It is the important mortality in cages among farmed fish, the debates around DNA injection vaccines, although effective, their safety and their side effects but also societal expectations for cleaner fish and security, lead research on new vaccine vectors. Several initiatives are financed by the European Union to develop a rapid and cost-effective approach to using bacteria in feed to make vaccines, in particular thanks to lactic bacteria whose DNA is modified (Boudinot, 2006). In fact, vaccinating farmed fish by injection is time-consuming and costly, so vaccines can be administered orally or by immersion by being added to feed or directly into water. This allows vaccinating many individuals at the same time while limiting the associated handling and stress.
Indeed, many tests are necessary because the antigens of the vaccines must be adapted to each species or not present a certain level of variability or they will not have any effect. For example, tests have been done with two species: ''Lepeophtheirus salmonis'' (from which the antigens were collected) and ''Caligus rogercresseyi'' (which was vaccinated with the antigens), although the homology between the two species is important, the level of variability made the protection ineffective (Fisheries and Oceans Canada, 2014).

====Recent vaccines development in aquaculture====
There are 24 vaccines available and one for lobsters. The first vaccine was used in the USA against enteric red mouth in 1976. However, there are 19 companies and some small stakeholders are producing vaccines for aquaculture nowadays. The novel approaches are a way forward to prevent the loss of 10% of aquaculture through disease. Genetically modified vaccines are not being used in the EU due to societal concerns and regulations. Meanwhile, DNA vaccines are now authorised in the EU.
There are challenges in fish vaccine development, immune response due to lack of potent adjuvants. Scientists are considering microdose application in future. But there are also opportunities in aquaculture vaccinology due to the low cost of technology, regulations change and novel antigen expression and delivery systems.<ref name=adams2019/>
In Norway subunit vaccine (VP2 peptide) against infectious pancreatic necrosis is being used. In Canada, a licensed DNA vaccine against Infectious hematopoietic necrosis has been launched for industry use.
Fish have large mucosal surfaces, so the preferred route is immersion, intraperitoneal and oral respectively. [[Nanoparticle]]s are in progress for delivery purposes. The common antibodies produced are IgM and IgT. Normally booster is not required in fish because more memory cells are produced in response to the booster rather than an increased level of antibodies.
mRNA vaccines are alternative to DNA vaccines because they are more safe, stable, easily producible at a large scale and mass immunization potential. Recently these are used in cancer prevention and therapeutics. Studies in rabies has shown that efficacy depends on dose and route of administration. These are still in infancy.<ref name=adams2019>{{cite journal |last1=Adams |first1=Alexandra |title=Progress, challenges and opportunities in fish vaccine development |journal=Fish & Shellfish Immunology |date=July 2019 |volume=90 |pages=210–214 |doi=10.1016/j.fsi.2019.04.066|pmid=31039441|bibcode=2019FSI....90..210A |hdl=1893/29828 |s2cid=141624380 |hdl-access=free }}</ref>

====Economic gains====
In 2014, the aquaculture produced fish overtook wild caught fish, in supply for human food. This means there is a huge demand for vaccines, in prevention of diseases. The reported annual loss fish, calculates to >10 billion USD. This is from approximately 10% of all fishes dying from infectious diseases.<ref name=adams2019/>
The high annual losses increases the demand for vaccines. Even though there are about 24 traditionally used vaccines, there is still demand for more vaccines. The breakthrough of DNA-vaccines has sunk the cost of vaccines.<ref name=adams2019/>

The alternative to vaccines would be antibiotics and chemotherapy, which are more expensive and with bigger drawbacks. DNA-vaccines have become the most cost-efficient method of preventing infectious diseases. This bodes well for DNA-vaccines becoming the new standard both in fish vaccines, and in general vaccines.<ref>{{cite journal |last1=Thorarinsson |first1=R |last2=Wolf |first2=JC |last3=Inami |first3=M |last4=Phillips |first4=L |last5=Jones |first5=G |last6=Macdonald |first6=AM |last7=Rodriguez |first7=JF |last8=Sindre |first8=H |last9=Skjerve |first9=E |last10=Rimstad |first10=E |last11=Evensen |first11=Ø |title=Effect of a novel DNA vaccine against pancreas disease caused by salmonid alphavirus subtype 3 in Atlantic salmon (Salmo salar). |journal=Fish & Shellfish Immunology |date=January 2021 |volume=108 |pages=116–126 |doi=10.1016/j.fsi.2020.12.002 |pmid=33285168|s2cid=227949940 |doi-access=free |bibcode=2021FSI...108..116T |hdl=11250/2830510 |hdl-access=free }}</ref>

===Salinization/acidification of soils===
Sediment from abandoned aquaculture farms can remain hypersaline, [[acid]]ic and eroded. This material can remain unusable for aquaculture purposes for long periods thereafter. Various chemical treatments, such as adding [[Lime (material)|lime]], can aggravate the problem by modifying the physicochemical characteristics of the sediment.<ref>{{Cite journal|last1=Martinez-Porchas|first1=Marcel|last2=Martinez-Cordova|first2=Luis R.|date=2012-04-29|title=World Aquaculture: Environmental Impacts and Troubleshooting Alternatives|journal=The Scientific World Journal|volume=2012|article-number=389623|doi=10.1100/2012/389623|issn=2356-6140|pmc=3353277|pmid=22649291 |doi-access=free }}</ref>

===Plastic pollution===
Aquaculture produces a range of marine debris, depending on the product and location. The most frequently documented type of plastic is expanded polystyrene (EPS), used extensively in floats and sea cage collars (MEPC 2020). Other common waste items include cage nets and plastic harvest bins. A review of aquaculture as a source of marine litter in the North, Baltic and Mediterranean Seas identified 64 different items, 19 of which were unique to aquaculture . Estimates of the amount of aquaculture waste entering the oceans vary widely, depending on the methodologies used. For example, in the European Economic Area loss estimates have varied from a low of 3,000 tonnes to 41,000 tonnes per year.<ref>{{Cite web |last=Environment |first=U. N. |date=2021-10-21 |title=Drowning in Plastics – Marine Litter and Plastic Waste Vital Graphics |url=http://www.unep.org/resources/report/drowning-plastics-marine-litter-and-plastic-waste-vital-graphics |access-date=2022-03-23 |website=UNEP – UN Environment Programme |language=en}}</ref>

==Ecological benefits==
{{see also|Nitrate vulnerable zone}}
While some forms of aquaculture can be devastating to ecosystems, such as shrimp farming in [[mangroves]], other forms can be beneficial. Shellfish aquaculture adds substantial [[filter feeding]] capacity to an environment which can significantly improve [[water quality]]. A single [[oyster]] can filter 15 gallons of water a day, removing microscopic algal cells. By removing these cells, shellfish are removing nitrogen and other nutrients from the system and either retaining it or releasing it as waste which sinks to the bottom. By harvesting these shellfish, the nitrogen they retained is completely removed from the system.<ref>{{cite journal|doi=10.2134/jeq2010.0203|pmid=21488516|title=Nutrient Bioassimilation Capacity of Aquacultured Oysters: Quantification of an Ecosystem Service|journal=Journal of Environmental Quality|volume=40|issue=1|pages=271–7|year=2011|last1=Higgins|first1=Colleen B.|last2=Stephenson|first2=Kurt|last3=Brown|first3=Bonnie L.|bibcode=2011JEnvQ..40..271H }}</ref> Raising and harvesting kelp and other macroalgae directly remove nutrients such as nitrogen and phosphorus. Repackaging these nutrients can relieve [[eutrophic]], or nutrient-rich, conditions known for their low [[Oxygen saturation|dissolved oxygen]] which can decimate [[species diversity]] and [[species abundance|abundance]] of marine life. Removing algal cells from the water also increases light penetration, allowing plants such as [[eelgrass]] to reestablish themselves and further increase oxygen levels.{{citation needed|date=October 2020}}<ref>{{cite journal |last1=Newell |first1=Roger |title=Top-down control of phytoplankton by oysters in Chesapeake Bay, USA |journal=Marine Ecology Progress Series |date=2007 |pages=293–298|doi=10.3354/meps341293 |doi-access=free}}</ref>

Aquaculture in an area can provide for crucial [[ecological function]]s for the inhabitants. Shellfish beds or cages can provide habitat structure. This structure can be used as shelter by invertebrates, small fish or [[crustacean]]s to potentially increase their abundance and maintain biodiversity. Increased shelter raises stocks of prey fish and small crustaceans by increasing recruitment opportunities in turn providing more prey for higher trophic levels. One study estimated that 10 square meters of [[oyster reef]] could enhance an ecosystem's [[biomass]] by 2.57&nbsp;kg<ref>{{cite journal|doi=10.3354/meps264249|title=Estimated enhancement of fish production resulting from restoring oyster reef habitat: quantitative valuation|journal=Marine Ecology Progress Series|volume=264|pages=249–264|year=2003|last1=Peterson|first1=CH|last2=Grabowski|first2=JH|last3=Powers|first3=SP|bibcode=2003MEPS..264..249P|doi-access=free}}</ref> [[Herbivore]] shellfish will also be preyed on. This moves energy directly from [[primary producer]]s to higher [[trophic level]]s potentially skipping out on multiple energetically costly trophic jumps which would increase biomass in the ecosystem.{{citation needed|date=October 2020}}

[[Seaweed farming]] is a [[carbon dioxide removal|carbon negative]] crop, with a high potential for [[climate change mitigation]].<ref>{{Cite journal|last1=Duarte|first1=Carlos M.|last2=Wu|first2=Jiaping|last3=Xiao|first3=Xi|last4=Bruhn|first4=Annette|last5=Krause-Jensen|first5=Dorte|date=2017|title=Can Seaweed Farming Play a Role in Climate Change Mitigation and Adaptation?|journal=Frontiers in Marine Science|language=en|volume=4|page=100 |doi=10.3389/fmars.2017.00100|issn=2296-7745|doi-access=free|bibcode=2017FrMaS...4..100D |hdl=10754/623247|hdl-access=free}}</ref> The IPCC [[Special Report on the Ocean and Cryosphere in a Changing Climate]] recommends "further research attention" as a mitigation tactic.<ref>{{Cite book|last1=Bindoff|first1=N. L.|title=IPCC Special Report on the Ocean and Cryosphere in a Changing Climate|last2=Cheung|first2=W. W. L.|last3=Kairo|first3=J. G.|last4=Arístegui|first4=J.|last5=Guinder|first5=V. A.|last6=Hallberg|first6=R.|last7=Hilmi|first7=N. J. M.|last8=Jiao|first8=N.|last9=Karim|first9=Md S.|year=2019|pages=447–587|chapter=Chapter 5: Changing Ocean, Marine Ecosystems, and Dependent Communities|ref={{harvid|IPCC SROCC Ch5|2019}} <!-- ipcc:20200202 -->|display-authors=4|chapter-url=https://www.ipcc.ch/site/assets/uploads/sites/3/2019/11/09_SROCC_Ch05_FINAL.pdf|first10=L.|last16=Williamson|first16=P.|last15=Tagliabue|first15=A.|last14=Suga|last12=Purca Cuicapusa|last13=Rinkevich|first13=B.|first12=S. R.|last11=O'Donoghue|first11=S.|last10=Levin|first14=T.}}</ref> Regenerative ocean farming is a polyculture farming system that grows a mix of seaweeds and shellfish while sequestering carbon, decreasing nitrogen in the water and increasing oxygen, helping to regenerate and restore local habitat like reef ecosystems.<ref>{{Cite web|last=Carr|first=Gabriela|date=2021-03-15|title=Regenerative Ocean Farming: How Can Polycultures Help Our Coasts?|url=https://smea.uw.edu/currents/regenerative-ocean-farming-how-can-polycultures-help-our-coasts/|url-status=live|access-date=2021-10-29|website=School of Marine and Environmental Affairs|language=en-US|archive-url=https://web.archive.org/web/20210316015237/https://smea.uw.edu/currents/regenerative-ocean-farming-how-can-polycultures-help-our-coasts/ |archive-date=2021-03-16}}</ref>

==Prospects==
Global [[wild fisheries]] are in decline, with valuable habitat such as [[estuary|estuaries]] in critical condition.<ref>[[Tietenberg, Tom]] (2006) ''Environmental and Natural Resource Economics: A Contemporary Approach''. Page 28. Pearson/Addison Wesley. {{ISBN|978-0-321-30504-6}}</ref> The aquaculture or [[fish farm|farming]] of [[piscivorous]] fish, like [[salmon]], does not help the problem because they need to eat products from other fish, such as [[fish meal]] and [[fish oil]]. Studies have shown that [[Aquaculture of salmon|salmon farming]] has major [[Salmon farming issues|negative impacts]] on wild salmon, as well as the [[forage fish]] that need to be caught to feed them.<ref name="Salmon Run">Knapp G, Roheim CA and Anderson JL (2007) [http://search.worldwildlife.org/cs.html?url=http://www.worldwildlife.org/what/globalmarkets/wildlifetrade/WWFBinaryitem4985.pdf&qt=The+Great+Salmon+Run&col=&n=4 ''The Great Salmon Run: Competition Between Wild And Farmed Salmon''] {{Webarchive|url=https://web.archive.org/web/20130805065108/http://search.worldwildlife.org/cs.html?url=http://www.worldwildlife.org/what/globalmarkets/wildlifetrade/WWFBinaryitem4985.pdf&qt=The+Great+Salmon+Run&col=&n=4 |date=2013-08-05 }} [[World Wildlife Fund]]. {{ISBN|978-0-89164-175-9}}</ref><ref>{{cite news |url=https://www.washingtonpost.com/wp-dyn/content/article/2007/12/13/AR2007121301190.html | newspaper=The Washington Post | title=Salmon Farming May Doom Wild Populations, Study Says | first1=Juliet | last1=Eilperin | first2=Marc | last2=Kaufman | date=2007-12-14}}</ref> Fish that are higher on the [[trophic level|food chain]] are less efficient sources of food energy.<ref name="Slobodkin1960">{{Cite journal
 |last=Slobodkin
 |first=L.B.
 |title=Ecological Energy Relationships at the Population Level
 |journal=The American Naturalist
 |volume=94
 |issue=879
 |pages=261–267
 |year=1960
 |doi=10.1086/282124
 |quote=The overall transfer efficiency of energy between trophic levels is a function of three separate processes... the overall between-level transfer efficiency ranges from 2 to 24%.
}}</ref>

Apart from fish and shrimp, some aquaculture undertakings, such as seaweed and filter-feeding bivalve molluscs like [[oyster]]s, [[clam]]s, [[mussel]]s and [[scallop]]s, are relatively benign and even environmentally restorative.<ref name="uscnews.usc.edu" /> Filter-feeders filter pollutants as well as nutrients from the water, improving water quality.<ref>{{cite journal
|title=Some aspects of water filtering activity of filter-feeders
|url=http://cat.inist.fr/?aModele=afficheN&cpsidt=17195907
|access-date=September 26, 2009
|author=OSTROUMOV S. A.
|journal=Hydrobiologia
|year=2005
|volume=542
| issue=1 |page=400
|doi=10.1007/s10750-004-1875-1
| bibcode=2005HyBio.542..275O |citeseerx=10.1.1.457.7375
|s2cid = 25050083}}</ref> [[Seaweeds]] extract nutrients such as inorganic nitrogen and [[phosphorus]] directly from the water,<ref name="Chopin et al. 2001" /> and filter-feeding [[mollusk]]s can extract nutrients as they feed on particulates, such as [[phytoplankton]] and [[detritus]].<ref name="Rice 2008">{{cite web
|url=http://mdsg.md.cgclientx.com/sites/default/files/files/105-Environmental%20Effects.pdf
|author=Rice, M.A.
|title=Environmental impacts of shellfish aquaculture
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|author-link=Michael A. Rice
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|archive-date=2015-10-05
}}</ref>

Some profitable aquaculture cooperatives promote sustainable practices.<ref>{{cite web
|url=http://ictsd.net/i/environment/11849/
|title=Aquaculture: Issues and Opportunities for Sustainable Production and Trade
|publisher=ITCSD
|date=July 2006
|access-date=2008-09-01
|archive-url=https://web.archive.org/web/20081120073308/http://ictsd.net/i/environment/11849/
|archive-date=2008-11-20
}}</ref> New methods lessen the risk of biological and chemical [[pollution]] through minimizing fish stress, fallowing netpens, and applying [[integrated pest management]]. [[Vaccine]]s are being used more and more to reduce [[antibiotic]] use for disease control.<ref>{{Cite web|last=Pew Oceans Commission|date=January 6, 2005|title=Marine Aquaculture in the United States|url=http://iis-db.stanford.edu/pubs/12217/marine_aquaculture_pew_2001.pdf|archive-url=https://web.archive.org/web/20050106122419/http://iis-db.stanford.edu/pubs/12217/marine_aquaculture_pew_2001.pdf|archive-date=2005-01-06}}</ref>

Onshore recirculating aquaculture systems, facilities using [[polyculture]] techniques, and properly sited facilities (for example, offshore areas with strong currents) are examples of ways to manage negative environmental effects.<ref name="SustainableMarineAquaculture">''The Sustainable Marine Aquaculture'', AENSI Web, 2012. https://www.aensiweb.com/old/aeb/2012/18-23.pdf</ref>

[[Recirculating aquaculture systems]] (RAS) recycle water by circulating it through filters to remove fish waste and food, and then recirculating it back into the tanks. This saves water, and the waste gathered can be used in [[compost]] or, in some cases, could even be treated and used on land. While RAS was developed with freshwater fish in mind, scientists associated with the [[Agricultural Research Service]] have found a way to rear saltwater fish using RAS in low-salinity waters.<ref name="Growing Premium Seafood-Inland!">{{cite web
|url= https://agresearchmag.ars.usda.gov/2009/feb/seafood
|title=Growing Premium Seafood-Inland!
|publisher=USDA Agricultural Research Service
|date=February 2009}}</ref> Although saltwater fish are raised in offshore cages or caught with nets in water that typically has a salinity of 35 [[parts per thousand]] (ppt), scientists were able to produce healthy pompano, a saltwater fish, in tanks with a salinity of only 5&nbsp;ppt. Commercializing low-salinity RAS is predicted to have positive environmental and economic effects. Unwanted nutrients from the fish food would not be added to the ocean, and the risk of transmitting diseases between wild and farm-raised fish would be greatly reduced. The price of expensive saltwater fish, such as the pompano and cobia used in the experiments, would be reduced. However, before any of this can be done researchers must study every aspect of the fish's lifecycle, including the amount of ammonia and nitrate the fish will tolerate in the water, what to feed the fish during each stage of its lifecycle, the [[stocking rate]] that will produce the healthiest fish, etc.<ref name="Growing Premium Seafood-Inland!" />

Some 16 countries now use [[geothermal energy]] for aquaculture, including China, [[Israel]], and the United States.<ref name="earth-policy">{{Cite book |editor-last=Brown |editor-first=Lester Russell |editor-link=Lester Brown|url={{google books |plainurl=y |id=-oK7QgAACAAJ}}|title=Plan B 2.0: Rescuing a Planet Under Stress and a Civilization in Trouble |date=2006 |publisher=W. W. Norton & Company |isbn=978-0-393-32831-8 |language=en|chapter-url=http://www.earth-policy.org/Books/PB2/pb2ch10.pdf |chapter=Stabilizing Climate|archive-url=https://web.archive.org/web/20070926235731/http://www.earth-policy.org/Books/PB2/pb2ch10.pdf |archive-date=2007-09-26 |page= 199}}</ref> In California, for example, 15 fish farms produce tilapia, bass, and catfish with warm water from underground. This warmer water enables fish to grow all year round and mature more quickly. Collectively, these California farms produce 4.5 million kilograms of fish annually.<ref name="earth-policy" />

===Global goals===
The UN [[Sustainable Development Goal 14]] ("life below water"), Target 14.7 includes aquaculture: "By 2030, increase the economic benefits to [[Small Island Developing States|small island developing states]] and [[least developed countries]] from the sustainable use of marine resources, including through sustainable management of fisheries, aquaculture and [[Sustainable tourism|tourism]]".<ref>United Nations (2017) Resolution adopted by the General Assembly on 6 July 2017, [[:File:A RES 71 313 E.pdf|Work of the Statistical Commission pertaining to the 2030 Agenda for Sustainable Development]] ([https://undocs.org/A/RES/71/313 A/RES/71/313])</ref><ref>Ritchie, Roser, Mispy, Ortiz-Ospina. "[https://sdg-tracker.org/oceans SDG 14 – Measuring progress towards the Sustainable Development Goals]." ''SDG-Tracker.org, website'' (2018).</ref> Aquaculture's contribution to GDP is not included in SDG Target 14.7, but methods for quantifying this have been explored by FAO.<ref name="Cai2019" />

== National laws, regulations, and management ==
Laws governing aquaculture practices vary greatly by country<ref>{{Cite web |title=Fisheries & Aquaculture Fact Sheets |url=http://www.fao.org/fishery/nalo/search/en |access-date=2021-07-25 |website=National Aquaculture Legislation Overview |publisher=Food and Agriculture Organization of the United Nations; Fisheries Division |location=Rome}}</ref> and are often not closely regulated or easily traceable.

In the United States, land-based and nearshore aquaculture is regulated at the [[National Aquaculture Act of 1980|federal]] and state levels;<ref>{{Cite web |title=U.S. Aquaculture Legislation Timeline |url=http://www.oceaneconomics.org/LMR/Aquaculture/fedPolicy.aspx |date=2007-08-01 |website=National Ocean Economics Program |publisher=Middlebury Institute of International Studies |location=Monterey, CA |access-date=2015-06-08 |archive-date=2015-06-02 |archive-url=https://web.archive.org/web/20150602071942/http://www.oceaneconomics.org/LMR/Aquaculture/fedPolicy.aspx }}</ref> however, no national laws govern [[offshore aquaculture]] in U.S. [[exclusive economic zone]] waters. In June 2011, the Department of Commerce and [[National Oceanic and Atmospheric Administration]] released national aquaculture policies<ref>{{Cite web|title=Commerce and NOAA release national aquaculture policies to increase domestic seafood production, create sustainable jobs, and restore marine habitats|url=http://www.noaanews.noaa.gov/stories2011/20110609_aquaculture.html|access-date=2015-06-08|website=www.noaanews.noaa.gov}}</ref> to address this issue and "to meet the growing demand for healthy seafood, to create jobs in coastal communities, and restore vital ecosystems." Large aquaculture facilities (i.e. those producing {{convert|20000|lb|kg}} per year) which discharge [[industrial wastewater|wastewater]] are required to obtain permits pursuant to the [[Clean Water Act]].<ref name=NPDES>
{{cite web |title=Aquaculture NPDES Permitting |url=https://www.epa.gov/npdes/aquaculture-npdes-permitting |date=2023-03-21 |website=National Pollutant Discharge Elimination System (NPDES) |publisher=U.S. Environmental Protection Agency (EPA) |location=Washington, D.C.}}</ref> Facilities that produce at least {{convert|100000|lb|kg}} of fish, molluscs or crustaceans a year are subject to specific national discharge standards.<ref>{{cite web |title=Concentrated Aquatic Animal Production Effluent Guidelines |url=https://www.epa.gov/eg/concentrated-aquatic-animal-production-effluent-guidelines |date=2023-06-22 |publisher=EPA}}</ref> Other permitted facilities are subject to effluent limitations that are developed on a case-by-case basis.<ref name=NPDES/>

==By country==
Aquaculture by Country:

{{World topic|Aquaculture in|title=Aquaculture by country|noredlinks=yes|state=show}}

==History==
[[File:Delta Pride Catfish farm harvest.jpg|thumb|left|Workers harvest catfish from the Delta Pride Catfish farms in Mississippi|alt= Photo of dripping, cup-shaped net, approximately {{convert|6|ft|m}} in diameter and equally tall, half-full of fish, suspended from crane boom, with four workers on and around larger, ring-shaped structure in water]]

The [[Gunditjmara]], a local [[Aboriginal Australian people]] in south-western [[Victoria (Australia)|Victoria]], Australia, may have raised [[short-finned eel]]s as early as about 4,580 [[BCE]].<ref name="bbnhl">{{cite web|title= National Heritage Places – Budj Bim National Heritage Landscape|url= http://www.environment.gov.au/heritage/places/national/budj-bim |access-date=30 January 2020|website=Australian Government. Dept of Agriculture, Water and the Environment}} See also attached documents: National Heritage List ''Location and Boundary Map'', and ''Government Gazette'', 20 July 2004.</ref> Evidence indicates they developed about {{convert|100|km2|sqmi|abbr=on}} of volcanic [[floodplain]]s in the vicinity of [[Lake Condah]] into a complex of channels and dams, and used woven [[Fishing trap|traps]] to capture [[eel]]s, and to preserve them to eat all year round.<ref>[http://www.abc.net.au/science/news/stories/s806276.htm Aborigines may have farmed eels, built huts] ABC Science News, 13 March 2003.</ref><ref>[http://www.lakecondah.com/budjbim.html Lake Condah Sustainability Project] {{Webarchive|url=https://archive.today/20130103171935/http://www.lakecondah.com/budjbim.html|date=2013-01-03}}. Retrieved 18 February 2010.</ref> The local [[Budj Bim heritage areas|Budj Bim Cultural Landscape]], a [[World Heritage Site]], is one of the oldest known aquaculture sites in the world.<ref>{{cite news|last1= Neal|first1= Matt |title= Ancient Indigenous aquaculture site Budj Bim added to UNESCO World Heritage list|newspaper= ABC News|date= 6 July 2019|url= https://www.abc.net.au/news/2019-07-06/indigenous-site-joins-pyramids-stonehenge-world-heritage-list/11271804|access-date= 14 July 2019 | quote = Not only does Budj Bim bust the myth that all Indigenous people were nomadic and not agriculturally inclined, it is also considered one of the oldest aquaculture sites in the world.}}</ref><ref name="bbwhl">{{cite web|date= 6 July 2019|title=World heritage Places – Budj Bim Cultural Landscape|url= http://www.environment.gov.au/heritage/places/world/budj-bim|access-date= 11 March 2020|website=Australian Government. Dept of the Environment and Energy}}</ref>

[[Oral tradition]] in China tells of the culture of the common carp, ''[[Cyprinus carpio]]'', as long ago as 2000–2100 BCE (around 4,000 years [[before present|BP]]), but the earliest significant evidence lies in the literature, in the earliest monograph on fish culture called ''The Classic of Fish Culture'', by [[Fan Li]], written around 475 BCE ({{circa|2475}} BP).<ref>{{cite web|title=History of Aquaculture|url= http://www.fao.org/docrep/field/009/ag158e/AG158E02.htm |access-date=August 23, 2009|publisher=Food and Agriculture Organization, United Nations}}</ref> Another ancient Chinese guide to aquaculture , wriiten by Yang Yu Jing around 460 BCE, shows that carp farming was becoming more sophisticated. The [[Jiahu]] site in China has circumstantial archeological evidence as possibly the oldest aquaculture locations, dating from 6200BCE (about 8,200 years BP), but this is speculative.<ref name="jiahu">{{cite news|last1= Smith|first1= Kiona N.|date= 17 September 2019|title= Aquaculture may be the future of seafood, but its past is ancient|work=[[Ars Technica]]|url= https://arstechnica.com/science/2019/09/fish-farming-may-be-much-older-than-we-thought/|access-date= 17 September 2019|archive-url=https://web.archive.org/web/20190917164315/https://arstechnica.com/science/2019/09/fish-farming-may-be-much-older-than-we-thought/|archive-date= 17 September 2019}}</ref> When the waters subsided after river floods, some fish, mainly [[carp]], were trapped in lakes. Early aquaculturists fed their brood using [[nymph (biology)|nymphs]] and [[silkworm]] faeces, and ate them.<ref name="sr">{{cite journal|last1=Sisma-Ventura|first1= Guy |last2= Tütken|first2= Thomas|last3= Zohar|first3= Irit|last4= Pack|first4= Andreas|last5= Sivan|first5= Dorit|last6= Lernau|first6= Omri|last7= Gilboa|first7= Ayelet|last8= Bar-Oz|first8= Guy|date= 2018|title= Tooth oxygen isotopes reveal Late Bronze Age origin of Mediterranean fish aquaculture and trade|journal=Scientific Reports|volume= 8|issue= 1 |page=14086|bibcode=2018NatSR...814086G|doi=10.1038/s41598-018-32468-1|pmc=6148281|pmid=30237483}}</ref>

[[Ancient Egyptians]] might have farmed fish (especially [[gilt-head bream]]) from [[Lake Bardawil]] about 1,500 BCE (about 3,500 BP), and they traded them with [[Canaan]].<ref name=sr/>

''[[Gim (food)|Gim]]'' cultivation is the oldest aquaculture in [[Korea]].<ref name="Gang">{{Cite web|last=강|first=제원 |title= gim|script-title= ko:김|url= http://encykorea.aks.ac.kr/Contents/Index?contents_id=E0008581|website=[[Encyclopedia of Korean Culture]]|publisher= [[Academy of Korean Studies]]|language=ko}}</ref> Early cultivation methods used [[bamboo]] or [[oak]] sticks;<ref name="Gang" /> newer methods utilizing nets replaced them in the 19th century.<ref name="Gang" /><ref name="EB">{{Cite web|title=gim|script-title=ko:김|url= http://premium.britannica.co.kr/bol/topic.asp?article_id=b03g1434a|archive-url= https://web.archive.org/web/20210224072904/http://premium.britannica.co.kr/bol/topic.asp?article_id=b03g1434a|archive-date= February 24, 2021|access-date=5 June 2017|website=[[Encyclopædia Britannica]]|language= ko}}</ref> [[Gim (food)#Floating rafts|Floating rafts]] have been used for mass production since the 1920s.<ref name="Gang" />

[[Japanese people]] cultivated [[seaweed]] by providing bamboo poles and, later, nets and [[oyster]] shells to serve as anchoring-surfaces for [[spore]]s.<ref>{{Cite web|last=Anitei|first=Stefan|title=... Make Unusual Aquaculture|url= https://news.softpedia.com/news/Make-Unusual-Aquaculture-45797.shtml|access-date= 2021-02-17|website= softpedia|date= 30 January 2007|language=english|archive-date=2021-09-29|archive-url= https://web.archive.org/web/20210929121940/https://news.softpedia.com/news/Make-Unusual-Aquaculture-45797.shtml}}</ref>

[[Ancient Rome|Romans]] bred fish in ponds and farmed oysters in coastal lagoons before 100 [[common era|CE]].<ref>{{cite journal|author1= McCann, Anna Marguerite|year= 1979|title= The Harbor and Fishery Remains at Cosa, Italy, by Anna Marguerite McCann|journal=Journal of Field Archaeology|volume=6|issue=4|pages=391–411|doi= 10.1179/009346979791489014 |jstor=529424}}</ref>
[[File:00 Ixelles - Abbaye - La Cambre 1.JPG|thumb|right|[[Fish pond]] of the [[La Cambre Abbey]] in [[City of Brussels|Brussels]], Belgium]]
In [[Middle Ages|medieval Europe]], early Christian [[monastery|monasteries]] adopted Roman aquacultural practices.<ref>
Jhingran, V.G., Introduction to aquaculture. 1987, United Nations Development Programme, Food and Agriculture Organization of the United Nations, Nigerian Institute for Oceanography and Marine Research.</ref> Aquaculture spread because people away from coasts and big rivers were otherwise dependant on fish which required salting in order to be preserved.<ref>{{cite book|last= Kurlansky|first= Mark|url= https://archive.org/details/isbn_9780965033503|title= Salt: A World History|year= 2002|url-access= registration}}</ref> Fish was an important food source in medieval Europe, when in average 150 days per year were days [[Fasting and abstinence in the Catholic Church|of fasting and abstinence]], and meat was prohibited.<ref name=wilmart>{{cite journal |last= Wilmart|first= Mickaël|date= 2001|title= Les étangs de Marcoussis. Un exemple d'exploitation piscicole dans la région parisienne à la fin du XVe siècle|url= https://shs.hal.science/halshs-00425001/document|journal= Bulletin de la Société historique et archéologique de Corbeil, de l'Essonne et du Hurepoix|issue= 71|pages= 7–18|access-date=8 May 2024}}</ref> Improvements in transportation during the 19th century made fresh fish easily available and inexpensive, even in inland areas, rendering aquaculture less popular. The 15th-century fishponds of the [[Třeboň|Trebon Basin]] in the present-day [[Czech Republic]] are maintained as a tentative [[UNESCO World Heritage Site]].<ref>{{cite web|title=Fishpond Network in the Trebon Basin|url= https://whc.unesco.org/en/tentativelists/1509/ |archive-url= https://web.archive.org/web/20151003161228/http://whc.unesco.org/en/tentativelists/1509/|archive-date=3 October 2015 |access-date=1 Oct 2015|publisher=[[UNESCO]]}}</ref>

[[Aquaculture in Samoa|Samoans]] practised "a traditional form of [[giant clam]] ranching".<ref>
{{cite book
 |author               = IBP Inc.
 |year                 = 2015
 |title                = Samoa Fishing and Aquaculture Industry Handbook - Strategic Information and Regulations
 |url                  = https://books.google.com/books?id=wV-zCwAAQBAJ
 |publication-place    = Washington DC
 |publisher            = International Business Publications, USA
 |page                 = 37
 |isbn                 = 978-1-5145-1948-6
 |access-date          = 21 April 2024
 |quote                = [...] in Samoa [...] a traditional form of giant clam ranching was practiced on village reefs or on lagoon [sic] where a community place giant clams in a fenced off area for special occasion or reserves for seafood supply in bad weather.
}} 
</ref>

[[Hawaii]]ans constructed [[Hawaiian aquaculture|oceanic fish ponds]]. A remarkable example is the [[Menehune Fishpond|"Menehune" fishpond]] dating from at least 1,000&nbsp;years ago, at Alekoko. Legend records its construction by the mythical [[Menehune]] dwarf-people.<ref>{{cite journal|last1= Costa-Pierce|first1= B.A.|year= 1987|title= Aquaculture in ancient Hawaii|url=http://hawaiiseed.org/wp-content/uploads/2012/11/aquaculture-ancient-hawaii-article.pdf |archive-url=https://ghostarchive.org/archive/20221009/http://hawaiiseed.org/wp-content/uploads/2012/11/aquaculture-ancient-hawaii-article.pdf |archive-date=2022-10-09 |url-status= live|journal= BioScience|volume=37|issue=5|pages=320–331|doi=10.2307/1310688|jstor=1310688}}</ref>

In the first half of the 18th century, German [[:de:Stephan Ludwig Jacobi|Stephan Ludwig Jacobi]] experimented with [[external fertilization]] of [[brown trout]] and [[salmon]]. He wrote an article "{{lang | de | Von der künstlichen Erzeugung der Forellen und Lachse}}" (''On the Artificial Production of Trout and Salmon'') summarizing his findings, and earning him a reputation as the founder of artificial fish-rearing.<ref>{{Cite web|title=Ein Lipper macht sich Gedanken ...|url=https://lippisches-landesmuseum.de/sonderausstellungen/archiv/2011/ein-lipper-macht-sich-gedanken/|access-date=2019-09-18|website=Lippisches Landesmuseum Detmold|language=de|quote=Stephan Ludwig Jacobi, vor 300 Jahren in Kalletal-Hohenhausen geboren, veröffentlichte 1768 den Aufsatz "Von der künstlichen Erzeugung der Forellen und Lachse" in den "Lippischen Intelligenzblättern" – und gilt damit zu Recht als Begründer der künstlichen Fischaufzucht.|archive-date=2019-12-09|archive-url=https://web.archive.org/web/20191209215057/https://lippisches-landesmuseum.de/sonderausstellungen/archiv/2011/ein-lipper-macht-sich-gedanken/}}</ref>  By the latter decades of the 18th century, oyster-farming had begun in estuaries along the Atlantic Coast of North America.<ref>{{cite web|date= 22 May 2015|title= A Brief History of Oystering in Narragansett Bay|url=http://web.uri.edu/quadangles/a-brief-history-of-oystering-in-narragansett-bay/|access-date=1 October 2015|publisher=URI Alumni Magazine, University of Rhode Island}}</ref>

The word "aquaculture" appeared in an 1855 newspaper article in reference to the harvesting of ice.<ref>{{Cite news |title= The cultivation of ice (1855) - on Newspapers.com|newspaper=The Baltimore Sun|url= https://www.newspapers.com/clip/3797987/the_cultivation_of_ice_1855/|access-date=2015-12-10}}</ref> It also appeared in descriptions of the terrestrial agricultural practise of [[subirrigation|sub-irrigation]] in the late-19th century<ref>{{Cite news|title= Agricultural. New agricultural practises by A. N. Cole. Subirrigation, methods and results (1888) - on Newspapers.com|newspaper=Oakland Tribune|url= https://www.newspapers.com/clip/3798119/agricultural_new_agricultural/|access-date= 2015-12-10}}</ref> before becoming associated primarily with the cultivation of aquatic plant- and animal-species. (The [[Oxford English Dictionary]] records the common modern usage of "aquaculture" from 1887;<ref>
{{oed | aquaculture}}
</ref>
and that of "aquiculture" from 1867.<ref>
{{oed | aquiculture}}
</ref>)

In 1859, Stephen Ainsworth of [[West Bloomfield, New York]], began experiments with [[brook trout]]. By 1864, Seth Green had established a commercial fish-hatching operation at Caledonia Springs, near [[Rochester, New York]]. By 1866, with the involvement of W. W. Fletcher of [[Concord, Massachusetts]], artificial [[Fish hatchery|fish-hatcheries]] operated both in both Canada and in the United States.<ref>Milner, James W. (1874). "The Progress of Fish-culture in the United States". United States Commission of Fish and Fisheries Report of the Commissioner for 1872 and 1873. 535 – 544 <http://penbay.org/cof/cof_1872_1873.html></ref> When the [[Dildo Island]] fish hatchery opened in [[Newfoundland]] in 1889, it was the largest and most advanced in the world. The word "aquaculture" was used in descriptions of the hatcheries experiments with cod and lobster in 1890.<ref>{{Cite news|title= Food from the sea. Remarkable results of the experiments in cod and lobster,(aquaculture, 1890) - on Newspapers.com|newspaper=Pittsburgh Dispatch|url= https://www.newspapers.com/clip/3798097/food_from_the_sea_remarkable_results/|access-date=2015-12-10}}</ref>

By the 1920s, the American Fish Culture Company of [[Carolina, Rhode Island]], founded in the 1870s, was one of the leading producers of trout.  During the 1940s, they perfected the method of manipulating the day- and night-cycle of fish so that they could be artificially spawned year-round.<ref>[[Michael A. Rice|Rice, M.A.]] 2010. "A brief history of the American Fish Culture Company 1877–1997". [[Rhode Island Historical Society|Rhode Island History]] 68(1):20–35. [http://works.bepress.com/cgi/viewcontent.cgi?article=1009&context=michael_rice web version] {{Webarchive|url= https://web.archive.org/web/20131203013521/http://works.bepress.com/cgi/viewcontent.cgi?article=1009&context=michael_rice|date=2013-12-03}}</ref>

Californians harvested wild [[kelp]] and attempted to manage supply around 1900, later labeling it a wartime resource.<ref>{{cite journal|last1= Neushul|first1= Peter|year= 1989|title= Seaweed for War: California's World War I Kelp Industry|journal=Technology and Culture|volume= 30|issue= 3|pages= 561–583|doi= 10.2307/3105951|jstor= 3105951|s2cid= 111835074 }}</ref>

{{clear}}

==See also==<!-- PLEASE RESPECT ALPHABETICAL ORDER -->
{{Portal|Water|Marine life}}
* [[Agroecology]]
* [[Alligator farm]]
* [[Certification for Aquaculture Professionals]]
* [[Fisheries science]]
* [[Fishery]]
* [[Industrial agriculture (animals)#Aquaculture|Industrial aquaculture]]
* [[List of commercially important fish species]]
* [[Maggot farming|Maggots used as food for fish]]
* [[Oyster farming]]
* [[Recirculating aquaculture system]]
* [[Resource decoupling]]

==Sources==
{{Free-content attribution
| title = The State of World Fisheries and Aquaculture 2024
| publisher = FAO
| page numbers = p.10
| documentURL = https://openknowledge.fao.org/items/06690fd0-d133-424c-9673-1849e414543d
| license statement URL = 
| license = [[CC BY 4.0]]
}}

==References==
{{Reflist|30em}}

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* Wyban, Carol Araki (1992) ''Tide and Current: Fishponds of Hawai'I'' [[University of Hawaiʻi]] Press:: {{ISBN|978-0-8248-1396-3}}
* Timmons, M.B., Ebeling, J.M., Wheaton, F.W., Summerfelt, S.T., Vinci, B.J., 2002. Recirculating Aquaculture Systems: 2nd edition. Cayuga Aqua Ventures.
* {{cite journal | last1 = Piedrahita | first1 = R.H. | year = 2003 | title = Reducing the potential environmental impacts of tank aquaculture effluents through intensification and recirculation | journal = Aquaculture | volume = 226 | issue = 1–4| pages = 35–44 | doi=10.1016/s0044-8486(03)00465-4| bibcode = 2003Aquac.226...35P }}
* {{cite journal | last1 = Klas | first1 = S. | last2 = Mozes | first2 = N. | last3 = Lahav | first3 = O. | year = 2006 | title = Development of a single-sludge denitrification method for nitrate removal from RAS effluents: Lab-scale results vs. model prediction | journal = Aquaculture | volume = 259 | issue = 1–4| pages = 342–353 | doi=10.1016/j.aquaculture.2006.05.049| bibcode = 2006Aquac.259..342K }}
{{Refend}}

===Free content work===
{{Free-content attribution
| title = In brief, The State of World Fisheries and Aquaculture, 2018
| author = FAO
| publisher = FAO
| page numbers =
| source =
| documentURL = http://www.fao.org/3/ca0191en/ca0191en.pdf
| license statement URL = https://commons.wikimedia.org/wiki/File:In_brief,_The_State_of_World_Fisheries_and_Aquaculture,_2018.pdf
| license = CC BY-SA 3.0 IGO}}

{{Free-content attribution
| title = Drowning in Plastics – Marine Litter and Plastic Waste Vital Graphics
| publisher = United Nations Environment Programme
| documentURL = https://www.unep.org/resources/report/drowning-plastics-marine-litter-and-plastic-waste-vital-graphics
| license statement URL = https://commons.wikimedia.org/wiki/File:United_Nations_Environment_Programme_Drowning_in_Plastics_%E2%80%93_Marine_Litter_and_Plastic_Waste_Vital_Graphics.pdf
| license = Cc BY-SA 3.0 IGO}}

==Further reading==
* Holmer, Marianne. ''Aquaculture in the Ecosystem''. Dordrecht, Netherlands: Springer, 2008.
* Molyneaux, Paul. ''Swimming in Circles: Aquaculture and the End of Wild Oceans''. New York: Thunder's Mouth Press, 2006.
* Stickney, Robert R. ''Aquaculture: An Introductory Text''. Oxford, UK; Cambridge, MA: CABI Publishing, 2005.
* World Bank. ''Changing the Face of the Waters: The Promise and Challenge of Sustainable Aquaculture''. Washington, DC: World Bank, 2007.

==External links==
{{Wiktionary}}
{{Commons category|Aquaculture}}
* [https://www.whoi.edu/know-your-ocean/ocean-topics/ocean-resources/aquaculture/ Aquaculture topic page from Woods Hole Oceanographic Institution]
* {{Cite web|title = Aquaculture Factsheet|url = http://waittinstitute.org/aquaculture/|access-date = 2015-06-08|publisher = Waitt Institute|archive-url = https://web.archive.org/web/20150617102308/http://waittinstitute.org/aquaculture/|archive-date = 2015-06-17}}
* [https://web.uri.edu/crc/ The Coastal Resources Center]
* [https://web.archive.org/web/20120118205534/http://aquaculture.noaa.gov/ NOAA aquaculture]
* [http://www.aquaculturehub.org The University of Hawaiʻi's AquacultureHub]
{{Library resources box |by=no |onlinebooks=no |others=no |about=yes |label=Aquaculture}}

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