A tuna is a
saltwater fish
Saltwater fish, also called marine fish or sea fish, are fish that live in seawater. Saltwater fish can swim and live alone or in a large group called a school.
Saltwater fish are very commonly kept in aquariums for entertainment. Many saltwater f ...
that belongs to the
tribe
The term tribe is used in many different contexts to refer to a category of human social group. The predominant worldwide usage of the term in English language, English is in the discipline of anthropology. This definition is contested, in p ...
Thunnini, a subgrouping of the
Scombridae
The mackerel, tuna, and bonito family, Scombridae, includes many of the most important and familiar food fishes. The family consists of 51 species in 15 genera and two subfamilies. All species are in the subfamily Scombrinae, except the butterfly ...
(
mackerel
Mackerel is a common name applied to a number of different species of pelagic fish, mostly from the family Scombridae. They are found in both temperate and tropical seas, mostly living along the coast or offshore in the oceanic environment.
...
) family. The Thunnini comprise 15
species
In biology, a species is the basic unit of classification and a taxonomic rank of an organism, as well as a unit of biodiversity. A species is often defined as the largest group of organisms in which any two individuals of the appropriate s ...
across five
genera
Genus ( plural genera ) is a taxonomic rank used in the biological classification of living and fossil organisms as well as viruses. In the hierarchy of biological classification, genus comes above species and below family. In binomial nomenclat ...
,
[ the sizes of which vary greatly, ranging from the ]bullet tuna
The bullet tuna, ''Auxis rochei'', is a species of tuna, in the family Scombridae, found circumglobally in tropical oceans, including the Mediterranean Sea, in open surface waters to depths of 50 m (164 ft). The population of bullet tu ...
(max length: , weight: ) up to the Atlantic bluefin tuna
The Atlantic bluefin tuna (''Thunnus thynnus'') is a species of tuna in the family Scombridae. It is variously known as the northern bluefin tuna (mainly when including Pacific bluefin as a subspecies), giant bluefin tuna or individuals exceed ...
(max length: , weight: ), which averages and is believed to live up to 50 years.
Tuna, opah
Opahs, also commonly known as moonfish, sunfish (not to be confused with Molidae), kingfish, redfin ocean pan are large, colorful, deep-bodied pelagic lampriform fishes comprising the small family Lampridae (also spelled Lamprididae).
The famil ...
and mackerel shark
The Lamniformes (, from Greek ''lamna'' "fish of prey") are an order of sharks commonly known as mackerel sharks (which may also refer specifically to the family Lamnidae). It includes some of the most familiar species of sharks, such as the gr ...
s are the only species of fish
Fish are aquatic, craniate, gill-bearing animals that lack limbs with digits. Included in this definition are the living hagfish, lampreys, and cartilaginous and bony fish as well as various extinct related groups. Approximately 95% of li ...
that can maintain a body temperature higher than that of the surrounding water. An active and agile predator
Predation is a biological interaction where one organism, the predator, kills and eats another organism, its prey. It is one of a family of common feeding behaviours that includes parasitism and micropredation (which usually do not kill th ...
, the tuna has a sleek, streamlined body, and is among the fastest-swimming pelagic fish
Pelagic fish live in the pelagic zone of ocean or lake waters—being neither close to the bottom nor near the shore—in contrast with demersal fish that do live on or near the bottom, and reef fish that are associated with coral reef ...
– the yellowfin tuna
The yellowfin tuna (''Thunnus albacares'') is a species of tuna found in pelagic waters of tropical and subtropical oceans worldwide.
Yellowfin is often marketed as ahi, from the Hawaiian language, Hawaiian , a name also used there for the closel ...
, for example, is capable of speeds of up to . Greatly inflated speeds can be found in early scientific reports and are still widely reported in the popular literature.
Found in warm seas, the tuna is commercially fished extensively as a food fish
Food is any substance consumed by an organism for nutritional support. Food is usually of plant, animal, or fungal origin, and contains essential nutrients, such as carbohydrates, fats, proteins, vitamins, or minerals. The substance is ingest ...
, and is popular as a bluewater game fish
Game fish, sport fish or quarry refer to popular fish pursued by recreational anglers, and can be freshwater or saltwater fish. Game fish can be eaten after being caught, or released after capture. Some game fish are also targeted commerciall ...
. As a result of overfishing
Overfishing is the removal of a species of fish (i.e. fishing) from a body of water at a rate greater than that the species can replenish its population naturally (i.e. the overexploitation of the fishery's existing fish stock), resulting in th ...
, some tuna species, such as the southern bluefin tuna
The southern bluefin tuna (''Thunnus maccoyii'') is a tuna of the family (biology), family Scombridae found in open southern Hemisphere waters of all the world's oceans mainly between 30th parallel south, 30°S and 50th parallel south, 50°S, to ...
, are threatened with extinction
Extinction is the termination of a kind of organism or of a group of kinds (taxon), usually a species. The moment of extinction is generally considered to be the death of the last individual of the species, although the capacity to breed and ...
.
Etymology
The term "tuna" comes from Spanish
Spanish might refer to:
* Items from or related to Spain:
**Spaniards are a nation and ethnic group indigenous to Spain
**Spanish language, spoken in Spain and many Latin American countries
**Spanish cuisine
Other places
* Spanish, Ontario, Cana ...
''atún'' < Andalusian Arabic ''at-tūn'', assimilated from ''al-tūn'' odern Arabic : 'tuna fish' < Middle Latin
Medieval Latin was the form of Literary Latin used in Roman Catholic Church, Roman Catholic Western Europe during the Middle Ages. In this region it served as the primary written language, though local languages were also written to varying deg ...
''thunnus''. ' is derived from grc, θύννος, thýnnos used for the Atlantic bluefin tuna
The Atlantic bluefin tuna (''Thunnus thynnus'') is a species of tuna in the family Scombridae. It is variously known as the northern bluefin tuna (mainly when including Pacific bluefin as a subspecies), giant bluefin tuna or individuals exceed ...
, that name in turn is ultimately derived from ''thýnō'', meaning "to rush, dart along".
Taxonomy
The Thunnini tribe is a monophyletic
In cladistics for a group of organisms, monophyly is the condition of being a clade—that is, a group of taxa composed only of a common ancestor (or more precisely an ancestral population) and all of its lineal descendants. Monophyletic gro ...
clade
A clade (), also known as a monophyletic group or natural group, is a group of organisms that are monophyletic – that is, composed of a common ancestor and all its lineal descendants – on a phylogenetic tree. Rather than the English term, ...
comprising 15 species in five genera
Genus ( plural genera ) is a taxonomic rank used in the biological classification of living and fossil organisms as well as viruses. In the hierarchy of biological classification, genus comes above species and below family. In binomial nomenclat ...
:
:* family Scombridae
The mackerel, tuna, and bonito family, Scombridae, includes many of the most important and familiar food fishes. The family consists of 51 species in 15 genera and two subfamilies. All species are in the subfamily Scombrinae, except the butterfly ...
:** tribe Thunnini: tunas
:*** genus ''Allothunnus
The slender tuna, ''Allothunnus fallai'', is a species of tuna, the only species in the genus ''Allothunnus'', found around the world in the southern oceans between latitudes 20° and 50° South, although there are two records of probable vagran ...
:'' slender tunas
:*** genus ''Auxis
''Auxis'' is a genus of ocean-dwelling ray-finned bony fish in the family Scombridae, and tribe Thunnini, also known as the tunas. ''Auxis'', commonly and collectively called the frigate tunas, is one of five genera of tunas which comprise th ...
:'' frigate tunas
:*** genus ''Euthynnus
''Euthynnus'' is a genus of ray-finned bony fish in the family Scombridae, or mackerel family, and in the tribe Thunnini, more commonly known as the tunas.
Species list
See also
* List of prehistoric bony fish
A ''list'' is any set of items ...
:'' little tunas
:*** genus ''Katsuwonus
The skipjack tuna (''Katsuwonus pelamis'') is a medium-sized perciform fish in the tuna family, Scombridae. It is otherwise known as the balaya (Sri Lanka), bakulan/kayu (North Borneo), tongkol/aya (Malay Peninsula/Indonesia), aku (Hawaii), cakal ...
:'' skipjack tunas
:*** genus ''Thunnus
''Thunnus'' is a genus of ocean-dwelling, ray-finned bony fish from the mackerel family, Scombridae. More specifically, ''Thunnus'' is one of five genera which make up the tribe Thunnini – a tribe that is collectively known as the tunas. Also ...
:'' albacores and true tunas
:**** subgenus
In biology, a subgenus (plural: subgenera) is a taxonomic rank directly below genus.
In the International Code of Zoological Nomenclature, a subgeneric name can be used independently or included in a species name, in parentheses, placed between t ...
''Thunnus (Thunnus
''Thunnus'' is a genus of ocean-dwelling, ray-finned bony fish from the mackerel family, Scombridae. More specifically, ''Thunnus'' is one of five genera which make up the tribe Thunnini – a tribe that is collectively known as the tunas. Also ...
)'': bluefin group
:**** subgenus ''Thunnus (Neothunnus
''Thunnus (Neothunnus)'' is a subgenus of ray-finned bony fishes in the Thunnini, or tuna, tribe. More specifically, ''Neothunnus'' is a subgenus of the genus ''Thunnus'', also known as the "true tunas". ''Neothunnus'' is sometimes referred t ...
)'': yellowfin group
The cladogram is a tool for visualizing and comparing the evolutionary relationships between taxa
In biology, a taxon (back-formation from ''taxonomy''; plural taxa) is a group of one or more populations of an organism or organisms seen by taxonomists to form a unit. Although neither is required, a taxon is usually known by a particular nam ...
, and is read left-to-right as if on a timeline. The following cladogram illustrates the relationship between the tunas and other tribes of the family Scombridae. For example, the cladogram illustrates that the skipjack tuna
The skipjack tuna (''Katsuwonus pelamis'') is a medium-sized perciform fish in the tuna family, Scombridae. It is otherwise known as the balaya (Sri Lanka), bakulan/kayu (North Borneo), tongkol/aya (Malay Peninsula/Indonesia), aku (Hawaii), cakal ...
s are more closely related to the true tuna
''Thunnus'' is a genus of ocean-dwelling, ray-finned bony fish from the mackerel family, Scombridae. More specifically, ''Thunnus'' is one of five genera which make up the tribe Thunnini – a tribe that is collectively known as the tunas. Also ...
s than are the slender tuna
The slender tuna, ''Allothunnus fallai'', is a species of tuna, the only species in the genus ''Allothunnus'', found around the world in the southern oceans between latitudes 20° and 50° South, although there are two records of probable vagran ...
s (the most primitive of the tunas), and that the next nearest relatives of the tunas are the bonito
Bonitos are a tribe of medium-sized, ray-finned predatory fish in the family Scombridae – a family it shares with the mackerel, tuna, and Spanish mackerel tribes, and also the butterfly kingfish. Also called the tribe Sardini, it consists of ...
s of the tribe Sardini.[
]
True species
The "true" tunas are those that belong to the genus ''Thunnus''. Until recently, it was thought that there were seven ''Thunnus'' species, and that Atlantic bluefin tuna
The Atlantic bluefin tuna (''Thunnus thynnus'') is a species of tuna in the family Scombridae. It is variously known as the northern bluefin tuna (mainly when including Pacific bluefin as a subspecies), giant bluefin tuna or individuals exceed ...
and Pacific bluefin tuna
The Pacific bluefin tuna (''Thunnus orientalis'') is a predatory species of tuna found widely in the northern Pacific Ocean, but it is migratory and also recorded as a visitor to the south Pacific.
In the past it was often included in '' T. thyn ...
were subspecies
In biological classification, subspecies is a rank below species, used for populations that live in different areas and vary in size, shape, or other physical characteristics (morphology), but that can successfully interbreed. Not all species ...
of a single species. In 1999, Collette established that based on both molecular and morphological considerations, they are in fact distinct species.
The genus ''Thunnus'' is further classified into two subgenera
In biology, a subgenus (plural: subgenera) is a taxonomic rank directly below genus.
In the International Code of Zoological Nomenclature, a subgeneric name can be used independently or included in a species name, in parentheses, placed between t ...
: ''Thunnus (Thunnus
''Thunnus'' is a genus of ocean-dwelling, ray-finned bony fish from the mackerel family, Scombridae. More specifically, ''Thunnus'' is one of five genera which make up the tribe Thunnini – a tribe that is collectively known as the tunas. Also ...
)'' (the bluefin group), and ''Thunnus (Neothunnus
''Thunnus (Neothunnus)'' is a subgenus of ray-finned bony fishes in the Thunnini, or tuna, tribe. More specifically, ''Neothunnus'' is a subgenus of the genus ''Thunnus'', also known as the "true tunas". ''Neothunnus'' is sometimes referred t ...
)'' (the yellowfin group).
:
Other species
The Thunnini tribe also includes seven additional species of tuna across four genera. They are:
:
Biology
Description
The tuna is a sleek and streamlined fish, adapted for speed. It has two closely spaced but separated dorsal fins
A dorsal fin is a fin located on the back of most marine and freshwater vertebrates within various taxa of the animal kingdom. Many species of animals possessing dorsal fins are not particularly closely related to each other, though through conv ...
on its back; The first fin is "depressible" – it can be laid down, flush, in a groove that runs along its back; it is supported by spines. Seven to 10 yellow finlet
Fins are distinctive anatomical features composed of bony spines or rays protruding from the body of a fish. They are covered with skin and joined together either in a webbed fashion, as seen in most bony fish, or similar to a flipper, as s ...
s run from the dorsal fins to the tail, which is lunate – curved like a crescent moon – and tapered to pointy tips. A tuna's pelvic fins are located below the base of the pectoral fins. Both dorsal and pelvic fins retract when the fish is swimming fast.
The tuna's body is countershaded
Countershading, or Thayer's law, is a method of camouflage in which an animal's coloration is darker on the top or upper side and lighter on the underside of the body. This pattern is found in many species of mammals, reptiles, birds, fish, and ...
to camouflage
Camouflage is the use of any combination of materials, coloration, or illumination for concealment, either by making animals or objects hard to see, or by disguising them as something else. Examples include the leopard's spotted coat, the ...
itself in deeper water when seen from above, its dorsal side is generally a metallic dark blue while the ventral or under side is silvery or whitish.[ The caudal peduncle, to which the tail is attached, is quite thin, with three stabilizing horizontal ]keel
The keel is the bottom-most longitudinal structural element on a vessel. On some sailboats, it may have a hydrodynamic and counterbalancing purpose, as well. As the laying down of the keel is the initial step in the construction of a ship, in Br ...
s on each side.[
]
Physiology
''Thunnus'' are widely but sparsely distributed throughout the oceans of the world, generally in tropical and temperate waters at latitude
In geography, latitude is a coordinate that specifies the north– south position of a point on the surface of the Earth or another celestial body. Latitude is given as an angle that ranges from –90° at the south pole to 90° at the north pol ...
s ranging between about 45° north and south
South is one of the cardinal directions or Points of the compass, compass points. The direction is the opposite of north and is perpendicular to both east and west.
Etymology
The word ''south'' comes from Old English ''sūþ'', from earlier Pro ...
of the equator. All tunas are able to maintain the temperature of certain parts of their body above the temperature of ambient seawater. For example, bluefin can maintain a core body temperature of , in water as cold as . Unlike other endothermic creatures such as mammals and birds, tuna do not maintain temperature within a relatively narrow range.
Tunas achieve endothermy
An endotherm (from Greek ἔνδον ''endon'' "within" and θέρμη ''thermē'' "heat") is an organism that maintains its body at a metabolically favorable temperature, largely by the use of heat released by its internal bodily functions inste ...
by conserving the heat generated through normal metabolism
Metabolism (, from el, μεταβολή ''metabolē'', "change") is the set of life-sustaining chemical reactions in organisms. The three main functions of metabolism are: the conversion of the energy in food to energy available to run cell ...
. In all tunas, the heart operates at ambient temperature
Colloquially, "room temperature" is a range of air temperatures that most people prefer for indoor settings. It feels comfortable to a person when they are wearing typical indoor clothing. Human comfort can extend beyond this range depending on ...
, as it receives cooled blood, and coronary circulation is directly from the gills
A gill () is a respiratory organ that many aquatic organisms use to extract dissolved oxygen from water and to excrete carbon dioxide. The gills of some species, such as hermit crabs, have adapted to allow respiration on land provided they are ...
.[ The '']rete mirabile
A rete mirabile (Latin for "wonderful net"; plural retia mirabilia) is a complex of arteries and veins lying very close to each other, found in some vertebrates, mainly warm-blooded ones. The rete mirabile utilizes countercurrent blood flow within ...
'' ("wonderful net"), the intertwining of veins and arteries in the body's periphery, allows nearly all of the metabolic heat from venous blood
Venous blood is deoxygenated blood which travels from the peripheral blood vessels, through the venous system into the right atrium of the heart. Deoxygenated blood is then pumped by the right ventricle to the lungs via the pulmonary artery whic ...
to be "re-claimed" and transferred to the arterial blood via a counter-current exchange
Countercurrent exchange is a mechanism occurring in nature and mimicked in industry and engineering, in which there is a crossover of some property, usually heat or some chemical, between two flowing bodies flowing in opposite directions to each ...
system, thus mitigating the effects of surface cooling. This allows the tuna to elevate the temperatures of the highly- aerobic tissues of the skeletal muscles, eyes and brain, which supports faster swimming speeds and reduced energy expenditure, and which enables them to survive in cooler waters over a wider range of ocean environments than those of other fish.
Also unlike most fish, which have white flesh, the muscle tissue of tuna ranges from pink to dark red. The red myotomal muscles derive their color from myoglobin
Myoglobin (symbol Mb or MB) is an iron- and oxygen-binding protein found in the cardiac and skeletal muscle tissue of vertebrates in general and in almost all mammals. Myoglobin is distantly related to hemoglobin. Compared to hemoglobin, myoglobi ...
, an oxygen-binding molecule, which tuna express in quantities far higher than most other fish. The oxygen-rich blood further enables energy delivery to their muscles.[
For powerful swimming animals like ]dolphin
A dolphin is an aquatic mammal within the infraorder Cetacea. Dolphin species belong to the families Delphinidae (the oceanic dolphins), Platanistidae (the Indian river dolphins), Iniidae (the New World river dolphins), Pontoporiidae (the ...
s and tuna, cavitation
Cavitation is a phenomenon in which the static pressure of a liquid reduces to below the liquid's vapour pressure, leading to the formation of small vapor-filled cavities in the liquid. When subjected to higher pressure, these cavities, cal ...
may be detrimental, because it limits their maximum swimming speed. Even if they have the power to swim faster, dolphins may have to restrict their speed, because collapsing cavitation bubbles on their tail are too painful. Cavitation also slows tuna, but for a different reason. Unlike dolphins, these fish do not feel the bubbles, because they have bony fins without nerve endings. Nevertheless, they cannot swim faster because the cavitation bubbles create a vapor film around their fins that limits their speed. Lesions have been found on tuna that are consistent with cavitation damage.[
]
Fishing
Commerce
Tuna is an important commercial fish. The International Seafood Sustainability Foundation
International Seafood Sustainability Foundation (ISSF) was formed in 2009 as a global, non-profit partnership among the tuna industry, scientists and World Wide Fund for Nature. The multistakeholder group states its mission is "to undertake scien ...
(ISSF) compiled a detailed scientific report on the state of global tuna stocks in 2009, which includes regular updates. According to the ISSF, the most important species for commercial and recreational tuna fisheries are yellowfin (''Thunnus albacares''), bigeye (''T. obesus''), bluefin (''T. thynnus'', ''T. orientalis'', and ''T. macoyii''), albacore (''T. alalunga''), and skipjack (''Katsuwonus pelamis'').
Based on catches from 2007, the report states:
The Australian government alleged in 2006 that Japan
Japan ( ja, 日本, or , and formally , ''Nihonkoku'') is an island country in East Asia. It is situated in the northwest Pacific Ocean, and is bordered on the west by the Sea of Japan, while extending from the Sea of Okhotsk in the north ...
had illegally overfished
Overfishing is the removal of a species of fish (i.e. fishing) from a body of water at a rate greater than that the species can replenish its population naturally (i.e. the overexploitation of the fishery's existing fish stock), resulting in the ...
southern bluefin by taking 12,000 to 20,000 tonnes per year instead of the agreed upon 6,000 tonnes; the value of such overfishing would be as much as US$2 billion. Such overfishing has severely damaged bluefin stocks. According to the WWF, "Japan's huge appetite for tuna will take the most sought-after stocks to the brink of commercial extinction
Extinction is the termination of a kind of organism or of a group of kinds (taxon), usually a species. The moment of extinction is generally considered to be the death of the last individual of the species, although the capacity to breed and ...
unless fisheries agree on more rigid quotas". Japan's Fisheries Research Agency counters that Australian and New Zealand tuna fishing companies under-report their total catches of southern bluefin tuna and ignore internationally mandated total allowable catch totals.
In recent years, opening day fish auctions at Tokyo's Tsukiji fish market
is a major tourist attraction for both domestic and overseas visitors in Tokyo.
The area contains retail markets, restaurants, and associated restaurant supply stores. Before 2018, it was the largest wholesale fish and seafood market in the wor ...
and Toyosu Market
The is a wholesale market in Tokyo, located in the Toyosu area of the Kōtō ward. There are two markets for seafood, one for general wholesale and one for bidding, and one market for fruits and vegetables, with each in its own building. Tourist ...
have seen record-setting prices for bluefin tuna, reflecting market demand. In each of 2010, 2011, 2012, 2013 and 2019, new record prices have been set for a single fish – the current record is 333.6 million japanese yen
The is the official currency of Japan. It is the third-most traded currency in the foreign exchange market, after the United States dollar (US$) and the euro. It is also widely used as a third reserve currency after the US dollar and the ...
(US$3.1 million) for a bluefin, or a unit price of JP¥ 1,200,000/kg (US$5,057/lb). The opening auction price for 2014 plummeted to less than 5% of the previous year's price, which had drawn complaints for climbing "way out of line". A summary of record-setting auctions are shown in the following table (highlighted values indicate new world records):
In November 2011, a different record was set when a fisherman in caught an tuna. It was captured inadvertently using a dragnet. Due to the laws and restrictions on tuna fishing in the United States, federal authorities impounded the fish because it was not caught with a rod and reel. Because of the tuna's deteriorated condition as a result of the trawl net, the fish sold for just under $5,000.
File:TunaFish.JPG, Tuna being weighed on Greek quay-side
File:Tsukiji Fish market and Tuna edit.jpg, Tuna at Tsukiji fish market
is a major tourist attraction for both domestic and overseas visitors in Tokyo.
The area contains retail markets, restaurants, and associated restaurant supply stores. Before 2018, it was the largest wholesale fish and seafood market in the wor ...
, Tokyo
File:Tuna cut half japan.jpg, Tuna cut in half for processing at Tsukuji fish market
Methods
Besides for edible purposes, many tuna species are caught frequently as game, often for recreation or for contests in which money is awarded based on weight. Larger specimens are notorious for putting up a fight while hooked, and have been known to injure people who try to catch them, as well as damage their equipment.
* Phoenicia
Phoenicia () was an ancient thalassocratic civilization originating in the Levant region of the eastern Mediterranean, primarily located in modern Lebanon. The territory of the Phoenician city-states extended and shrank throughout their histor ...
n technique for trapping and catching Atlantic bluefin tuna
The Atlantic bluefin tuna (''Thunnus thynnus'') is a species of tuna in the family Scombridae. It is variously known as the northern bluefin tuna (mainly when including Pacific bluefin as a subspecies), giant bluefin tuna or individuals exceed ...
called '' Almadraba'', still used today in Portugal, Spain, Morocco and Italy which uses a maze of nets. In Sicily, the same method is called ''Tonnara
''Mattanza'', literally 'slaughter' or 'killing' in Italian, also known as ''Almadraba'' in Spanish and ''Almadrava'' in Portuguese, is a traditional tuna fishing technique that uses a series of large nets to trap and exhaust the fish.
There ar ...
''.
* Fish farming (cage system)[
* ]Tuna ranching
A tuna is a saltwater fish that belongs to the tribe Thunnini, a subgrouping of the Scombridae (mackerel) family. The Thunnini comprise 15 species across five genera, the sizes of which vary greatly, ranging from the bullet tuna (max length: ...
* Longline fishing
Longline fishing, or longlining, is a commercial fishing angling technique that uses a long ''main line'' with baited hooks attached at intervals via short branch lines called ''snoods'' or ''gangions''.[Purse seine
Seine fishing (or seine-haul fishing; ) is a method of fishing that employs a surrounding net, called a seine, that hangs vertically in the water with its bottom edge held down by weights and its top edge buoyed by floats. Seine nets can be dep ...]
s
* Pole and line
* Harpoon gun
A harpoon cannon is a whaling implement developed in the late 19th century and most used in the 20th century. It would be mounted on the bow of a whale catcher, where it could be easily aimed with a wide field of view at the target. Powered by b ...
* Big game fishing
Big-game fishing, also known as offshore sportfishing, offshore gamefishing or blue-water fishing, is a form of recreational fishing targeting large game fish, usually done on a large body of water such as the ocean.
History
Big-game fishing st ...
* Fish aggregating device
A fish aggregating (or aggregation) device (FAD) is a man-made object used to attract ocean-going pelagic fish such as marlin, tuna and mahi-mahi (dolphin fish). They usually consist of buoys or floats tethered to the ocean floor with concrete bloc ...
Association with whaling
In 2005, Nauru
Nauru ( or ; na, Naoero), officially the Republic of Nauru ( na, Repubrikin Naoero) and formerly known as Pleasant Island, is an island country and microstate in Oceania, in the Central Pacific. Its nearest neighbour is Banaba Island in Ki ...
, defending its vote from Australian criticism at that year's meeting of the International Whaling Commission
The International Whaling Commission (IWC) is a specialised regional fishery management organisation, established under the terms of the 1946 International Convention for the Regulation of Whaling (ICRW) to "provide for the proper conservation of ...
, argued that some whale
Whales are a widely distributed and diverse group of fully aquatic placental marine mammals. As an informal and colloquial grouping, they correspond to large members of the infraorder Cetacea, i.e. all cetaceans apart from dolphins and ...
species have the potential to devastate Nauru's tuna stocks, and that Nauru's food security and economy relies heavily on fishing. Despite this, Nauru does not permit whaling
Whaling is the process of hunting of whales for their usable products such as meat and blubber, which can be turned into a type of oil that became increasingly important in the Industrial Revolution.
It was practiced as an organized industry ...
in its own waters and does not allow other fishing vessels to take or intentionally interact with marine mammals in its Exclusive Economic Zone. In 2010 and 2011, Nauru supported Australian proposals for a western Pacific-wide ban on tuna purse-seining in the vicinity of marine mammals – a measure which was agreed by the Western and Central Pacific Fisheries Commission at its eighth meeting in March 2012.
Association with dolphins
Dolphin
A dolphin is an aquatic mammal within the infraorder Cetacea. Dolphin species belong to the families Delphinidae (the oceanic dolphins), Platanistidae (the Indian river dolphins), Iniidae (the New World river dolphins), Pontoporiidae (the ...
s swim beside several tuna species. These include yellowfin tuna in the eastern Pacific Ocean, but not albacore. Tuna schools are believed to associate themselves with dolphins for protection against sharks, which are tuna predator
Predation is a biological interaction where one organism, the predator, kills and eats another organism, its prey. It is one of a family of common feeding behaviours that includes parasitism and micropredation (which usually do not kill th ...
s.
Commercial fishing vessels used to exploit this association by searching for dolphin pods. Vessels would encircle the pod with nets to catch the tuna beneath. The nets were prone to entangling dolphins, injuring or killing them. Public outcry and new government regulations, which are now monitored by NOAA
The National Oceanic and Atmospheric Administration (abbreviated as NOAA ) is an United States scientific and regulatory agency within the United States Department of Commerce that forecasts weather, monitors oceanic and atmospheric conditio ...
have led to more dolphin-friendly methods, now generally involving lines rather than nets. There are neither universal independent inspection programs nor verification of dolphin safety, so these protections are not absolute. According to Consumers Union, the resulting lack of accountability means claims of tuna that is "dolphin safe
Dolphin-safe labels are used to denote compliance with laws or policies designed to minimize dolphin fatalities during fishing for tuna destined for canning.
Some labels impose stricter requirements than others. Dolphin-safe tuna labeling origina ...
" should be given little credence.
Fishery practices have changed to be dolphin friendly, which has caused greater bycatch
Bycatch (or by-catch), in the fishing industry, is a fish or other marine species that is caught unintentionally while fishing for specific species or sizes of wildlife. Bycatch is either the wrong species, the wrong sex, or is undersized or juve ...
including shark
Sharks are a group of elasmobranch fish characterized by a cartilaginous skeleton, five to seven gill slits on the sides of the head, and pectoral fins that are not fused to the head. Modern sharks are classified within the clade Selachimo ...
s, turtle
Turtles are an order of reptiles known as Testudines, characterized by a special shell developed mainly from their ribs. Modern turtles are divided into two major groups, the Pleurodira (side necked turtles) and Cryptodira (hidden necked tu ...
s and other oceanic fish
Pelagic fish live in the pelagic zone of ocean or lake waters—being neither close to the bottom nor near the shore—in contrast with demersal fish that do live on or near the bottom, and reef fish that are associated with coral reefs ...
. Fishermen no longer follow dolphins, but concentrate their fisheries around floating objects such as fish aggregation device
A fish aggregating (or aggregation) device (FAD) is a man-made object used to attract ocean-going pelagic fish such as marlin, tuna and mahi-mahi (dolphin fish). They usually consist of buoys or floats tethered to the ocean floor with concrete bloc ...
s, also known as FADs, which attract large populations of other organisms. Measures taken thus far to satisfy the public demand to protect dolphins can be potentially damaging to other species as well.
Aquaculture
Increasing quantities of high-grade tuna caught at sea are reared in net pens and fed bait fish. In Australia, former fishermen raise southern bluefin tuna
The southern bluefin tuna (''Thunnus maccoyii'') is a tuna of the family (biology), family Scombridae found in open southern Hemisphere waters of all the world's oceans mainly between 30th parallel south, 30°S and 50th parallel south, 50°S, to ...
(''Thunnus maccoyii'') and another bluefin species. Farming its close relative, the Atlantic bluefin tuna
The Atlantic bluefin tuna (''Thunnus thynnus'') is a species of tuna in the family Scombridae. It is variously known as the northern bluefin tuna (mainly when including Pacific bluefin as a subspecies), giant bluefin tuna or individuals exceed ...
, ''Thunnus thynnus'', is beginning in the Mediterranean
The Mediterranean Sea is a sea connected to the Atlantic Ocean, surrounded by the Mediterranean Basin and almost completely enclosed by land: on the north by Western and Southern Europe and Anatolia, on the south by North Africa, and on the e ...
, North America
North America is a continent in the Northern Hemisphere and almost entirely within the Western Hemisphere. It is bordered to the north by the Arctic Ocean, to the east by the Atlantic Ocean, to the southeast by South America and the Car ...
and Japan. Hawaii
Hawaii ( ; haw, Hawaii or ) is a state in the Western United States, located in the Pacific Ocean about from the U.S. mainland. It is the only U.S. state outside North America, the only state that is an archipelago, and the only stat ...
approved permits for the first U.S. offshore farming of bigeye tuna in water deep in 2009.
Japan is the biggest tuna consuming nation and is also the leader in tuna farming research. Japan first successfully farm-hatched and raised bluefin tuna in 1979. In 2002, it succeeded in completing the reproduction cycle and in 2007, completed a third generation. The farm breed is known as Kindai tuna. Kindai is the contraction of Kinki University in Japanese (Kinki daigaku). In 2009, Clean Seas, an Australian company which has been receiving assistance from Kinki University managed to breed southern bluefin tuna in captivity and was awarded the second place in World's Best Invention of 2009 by ''Time'' magazine.
Food
Fresh and frozen
The fresh or frozen flesh of tuna is widely regarded as a delicacy in most areas where it is shipped, being prepared in a variety of ways. When served as a steak
A steak is a thick cut of meat generally sliced across the muscle fibers, sometimes including a bone. It is normally grilled or fried. Steak can be diced, cooked in sauce, such as in steak and kidney pie, or minced and formed into patties, ...
, the meat of most species is known for its thickness and tough texture. In the U.K., supermarkets began flying in fresh tuna steaks in the late 1990s, which helped to increase the popularity of using fresh tuna in cooking; by 2009, celebrity chefs regularly featured fresh tuna in salads, wraps, and char-grilled dishes.
Served raw
Various species of tuna are often served raw in Japanese cuisine
Japanese cuisine encompasses the regional and traditional foods of Japan, which have developed through centuries of political, economic, and social changes. The traditional cuisine of Japan (Japanese: ) is based on rice with miso soup and other ...
as sushi
is a Japanese cuisine, Japanese dish of prepared , usually with some sugar and salt, accompanied by a variety of , such as seafood, often raw, and vegetables. Styles of sushi and its presentation vary widely, but the one key ingredient is " ...
or sashimi
is a Japanese delicacy consisting of fresh raw fish or meat sliced into thin pieces and often eaten with soy sauce.
Origin
The word ''sashimi'' means "pierced body", i.e. "刺身" = ''sashimi'', where 刺 し = ''sashi'' (pierced, stuck) ...
.
Commercial sashimi tuna may have their coloration fixated by pumping carbon monoxide
Carbon monoxide (chemical formula CO) is a colorless, poisonous, odorless, tasteless, flammable gas that is slightly less dense than air. Carbon monoxide consists of one carbon atom and one oxygen atom connected by a triple bond. It is the simple ...
(CO) into bags containing the tuna, and holding it at 4 °C. For a 2-inch tuna steak, this requires 24 hours. The fish is then vacuum sealed and frozen. In Japan, color fixation using CO is prohibited.
Tuna consumption increases the risk of getting cancer.
File:Tuna_Sushi.jpg,
File:Tuna salad 001.jpg,
File:tuna steak.JPG,
File:Tekkadon_001.jpg,
File:Katsuobushi 02.jpg,
File:Mojama de atun.JPG,
Canned
Tuna is canned in edible oil
An oil is any nonpolar chemical substance that is composed primarily of hydrocarbons and is hydrophobic (does not mix with water) & lipophilic (mixes with other oils). Oils are usually flammable and surface active. Most oils are unsaturated ...
s, in brine
Brine is a high-concentration solution of salt (NaCl) in water (H2O). In diverse contexts, ''brine'' may refer to the salt solutions ranging from about 3.5% (a typical concentration of seawater, on the lower end of that of solutions used for br ...
, in water, and in various sauces. Tuna may be processed and labeled as "solid", "chunked" ("chunk") or "flaked". When tuna is canned and packaged for sale, the product is sometimes called tuna fish (U.S.), a calque
In linguistics, a calque () or loan translation is a word or phrase borrowed from another language by literal word-for-word or root-for-root translation. When used as a verb, "to calque" means to borrow a word or phrase from another language wh ...
(loan translation) from the German
German(s) may refer to:
* Germany (of or related to)
**Germania (historical use)
* Germans, citizens of Germany, people of German ancestry, or native speakers of the German language
** For citizens of Germany, see also German nationality law
**Ger ...
'' Thunfisch''. Canned tuna is sometimes used as food for pets, especially cats.
;Australia
Canned tuna was first produced in Australia in 1903 and quickly became popular.['' Choice'': Jan/Feb 2004.]
In the early 1980s canned tuna in Australia was most likely southern bluefin, it was usually yellowfin, skipjack, or tongol
''Thunnus tonggol'' is a species of tuna of tropical Indo-West Pacific waters.
It is commonly known as the longtail tuna or northern bluefin tuna.Hutchins, B. & Swainston, R. (1986). ''Sea Fishes of Southern Australia.'' pp. 104 & 141. Allen, G. ...
(labelled "northern bluefin" or "longtail").
Australian standards once required cans of tuna to contain at least 51% tuna, but those regulations were dropped in 2003.['' Choice'', August 2003.] The remaining weight is usually oil or water.
;United States
The product became more plentiful in the United States in the late 1940s. In 1950, 8,500,000 pounds of canned tuna were produced, and the U.S. Department of Agriculture
The United States Department of Agriculture (USDA) is the federal executive department responsible for developing and executing federal laws related to farming, forestry, rural economic development, and food. It aims to meet the needs of com ...
classified it as a "plentiful food".
In the United States, 52% of canned tuna is used for sandwich
A sandwich is a food typically consisting of vegetables, sliced cheese or meat, placed on or between slices of bread, or more generally any dish wherein bread serves as a container or wrapper for another food type. The sandwich began as a po ...
es; 22% for tuna salad
Tuna salad starts with a blend of two main ingredients: tuna and mayonnaise. The tuna used is usually pre-cooked, canned, and packaged in water or oil. Pickles, celery, relish, and onion are foremost among the ingredients that are often added. Whe ...
s; and 15% for tuna casserole
Tuna casserole is a casserole primarily made with pasta (or rice) and canned tuna, with peas and corn sometimes added. The dish is often topped with potato chips, corn flakes, bread crumbs or canned fried onions. Tuna casserole is a common dish ...
s and dried, prepackaged meal kit
A meal kit is a subscription service–foodservice business model where a company sends customers pre-portioned and sometimes partially-prepared food ingredients and recipes to prepare homecooked meals. Services that send pre-cooked meals ...
s, such as General Mills
General Mills, Inc., is an American multinational manufacturer and marketer of branded processed consumer foods sold through retail stores. Founded on the banks of the Mississippi River at Saint Anthony Falls in Minneapolis, the company orig ...
's Tuna Helper
A tuna is a saltwater fish that belongs to the tribe Thunnini, a subgrouping of the Scombridae ( mackerel) family. The Thunnini comprise 15 species across five genera, the sizes of which vary greatly, ranging from the bullet tuna (max lengt ...
line.["Tuna". ''Modern Marvels'', 4 February 2010.] Other canned tuna dishes include tuna melt
A melt sandwich is a type of hot sandwich containing cheese (sometimes grated) and some type of filling such as meat or vegetables. The sandwich is then heated until the cheese is melted. It is the filling that establishes the melt sandwich as ...
s (a type of sandwich where the tuna is mixed with mayonnaise and served on bread with cheese melted on top); salade niçoise
''Salade niçoise'' (), ''salada nissarda'' in the Niçard dialect of the Occitan language, ''insalata nizzarda'' in Italian, is a salad that originated in the French city of Nice. It is traditionally made of tomatoes, hard-boiled eggs, Niçois ...
(a salad made of tuna, olives, green beans, potatoes, hard-boiled eggs and anchovy dressing); and tuna burgers (served on buns).
In the United States, the Food and Drug Administration
The United States Food and Drug Administration (FDA or US FDA) is a List of United States federal agencies, federal agency of the United States Department of Health and Human Services, Department of Health and Human Services. The FDA is respon ...
(FDA) regulates canned tuna (see part ''c'').
;Precooked
As tunas are often caught far from where they are processed, poor interim conservation can lead to spoilage. Tuna is typically gutted
Disembowelment or evisceration is the removal of some or all of the organs of the gastrointestinal tract (the bowels, or viscera), usually through a horizontal incision made across the abdominal area. Disembowelment may result from an accident ...
by hand, and later precooked for prescribed times of 45 minutes to three hours. The fish are then cleaned and fillet
Fillet may refer to:
*Annulet (architecture), part of a column capital, also called a fillet
*Fillet (aircraft), a fairing smoothing the airflow at a joint between two components
*Fillet (clothing), a headband
*Fillet (cut), a piece of meat
*Fille ...
ed, canned (and sealed), with the dark lateral blood meat often separately canned for pet food
Pet food is animal feed intended for consumption by pets. Typically sold in pet stores and supermarkets, it is usually specific to the type of animal, such as dog food or cat food. Most meat used for animals is a byproduct of the human food indu ...
( cat or dog
The dog (''Canis familiaris'' or ''Canis lupus familiaris'') is a domesticated descendant of the wolf. Also called the domestic dog, it is derived from the extinct Pleistocene wolf, and the modern wolf is the dog's nearest living relative. Do ...
). The sealed can is then heated under pressure (called " retort cooking") for 2–4 hours. This process kills any bacteria, but retains the histamine
Histamine is an organic nitrogenous compound involved in local immune responses, as well as regulating physiological functions in the gut and acting as a neurotransmitter for the brain, spinal cord, and uterus. Since histamine was discovered in ...
that may have been produced by those bacteria, and so may still taste spoiled. The international standard sets the maximum histamine level at 200 milligrams per kilogram. An Australian study of 53 varieties of unflavored canned tuna found none to exceed the safe histamine level, although some had "off" flavors.
;Light and white
In some markets, depending upon the color of the flesh of the tuna species, the can is marked as "light" or "white" meat, with "light" meaning a greyish pink color and "white" meaning a light pink color. In the United States, only albacore can legally be sold in canned form as "white meat tuna"; in other countries, yellowfin is also acceptable.
; Ventresca tuna
Ventresca tuna (from '' ventre'', the Italian word for belly), is a luxury canned tuna, from the fatty bluefin tuna belly, also used in sushi as toro.
Nutrition
Canned light tuna in oil is 29% protein
Proteins are large biomolecules and macromolecules that comprise one or more long chains of amino acid residues. Proteins perform a vast array of functions within organisms, including catalysing metabolic reactions, DNA replication, respo ...
, 8% fat
In nutrition science, nutrition, biology, and chemistry, fat usually means any ester of fatty acids, or a mixture of such chemical compound, compounds, most commonly those that occur in living beings or in food.
The term often refers spec ...
, 60% water, and contains no carbohydrate
In organic chemistry, a carbohydrate () is a biomolecule consisting of carbon (C), hydrogen (H) and oxygen (O) atoms, usually with a hydrogen–oxygen atom ratio of 2:1 (as in water) and thus with the empirical formula (where ''m'' may or ma ...
s, while providing 200 calorie
The calorie is a unit of energy. For historical reasons, two main definitions of "calorie" are in wide use. The large calorie, food calorie, or kilogram calorie was originally defined as the amount of heat needed to raise the temperature of on ...
s in a 100 gram reference amount (table). It is a rich source (20% or more of the Daily Value, DV) of phosphorus
Phosphorus is a chemical element with the symbol P and atomic number 15. Elemental phosphorus exists in two major forms, white phosphorus and red phosphorus, but because it is highly reactive, phosphorus is never found as a free element on Ear ...
(44% DV) and vitamin D
Vitamin D is a group of fat-soluble secosteroids responsible for increasing intestinal absorption of calcium, magnesium, and phosphate, and many other biological effects. In humans, the most important compounds in this group are vitamin D3 (c ...
(45% DV), and a moderate source of iron
Iron () is a chemical element with symbol Fe (from la, ferrum) and atomic number 26. It is a metal that belongs to the first transition series and group 8 of the periodic table. It is, by mass, the most common element on Earth, right in f ...
(11% DV).
Mercury and health
Mercury content in tuna can vary widely. Among those calling for improved warnings about mercury in tuna is the American Medical Association
The American Medical Association (AMA) is a professional association and lobbying group of physicians and medical students. Founded in 1847, it is headquartered in Chicago, Illinois. Membership was approximately 240,000 in 2016.
The AMA's state ...
, which adopted a policy that physicians should help make their patients more aware of the potential risks. A study published in 2008 found that mercury distribution in the meat of farmed tuna is inversely related to the lipid content, suggesting that higher lipid concentration within edible tissues of tuna raised in captivity might, other factors remaining equal, have a diluting effect on mercury content. Mackerel tuna
''Euthynnus affinis'', the mackerel tuna, little tuna, wavyback skipjack tuna, kawakawa, or tongkol is a species of ray-finned bony fish in the family Scombridae, or mackerel family. It belongs to the tribe Thunnini, better known as the tunas. ...
is one species of tuna that is lower in mercury concentration than skipjack or yellowfin, but this species is known as "black meat" or "dark meat" tuna, which is a lower grade for canning because of the color, unfavorable flavor, and poor yield.
In March 2004, the United States FDA
The United States Food and Drug Administration (FDA or US FDA) is a federal agency of the Department of Health and Human Services. The FDA is responsible for protecting and promoting public health through the control and supervision of food s ...
issued guidelines recommending that pregnant women, nursing mothers, and children limit their intake of tuna and other predatory fish. The Environmental Protection Agency provides guidelines on how much canned tuna is safe to eat. Roughly speaking, the guidelines recommend one can of light tuna per week for individuals weighing less than , and two cans per week for those who weigh more. In 2007, it was reported that some canned light tuna such as yellowfin tuna
The yellowfin tuna (''Thunnus albacares'') is a species of tuna found in pelagic waters of tropical and subtropical oceans worldwide.
Yellowfin is often marketed as ahi, from the Hawaiian language, Hawaiian , a name also used there for the closel ...
is significantly higher in mercury than skipjack, and caused Consumers Union and other activist groups to advise pregnant women to refrain from consuming canned tuna. In 2009, a California appeals court upheld a ruling that canned tuna does not need warning labels as the methylmercury
Methylmercury (sometimes methyl mercury) is an organometallic cation with the formula . It is the simplest organomercury compound. Methylmercury is extremely toxic, and its derivatives are the major source of organic mercury for humans. It is a ...
is naturally occurring.
A January 2008 report revealed potentially dangerous levels of mercury
Mercury commonly refers to:
* Mercury (planet), the nearest planet to the Sun
* Mercury (element), a metallic chemical element with the symbol Hg
* Mercury (mythology), a Roman god
Mercury or The Mercury may also refer to:
Companies
* Merc ...
in certain varieties of sushi
is a Japanese cuisine, Japanese dish of prepared , usually with some sugar and salt, accompanied by a variety of , such as seafood, often raw, and vegetables. Styles of sushi and its presentation vary widely, but the one key ingredient is " ...
tuna, reporting levels "so high that the Food and Drug Administration could take legal action to remove the fish from the market."
Management and conservation
The main tuna fishery management bodies are the Western and Central Pacific Fisheries Commission
The Western and Central Pacific Fisheries Commission (WCPFC) is both a general and a tuna regional fisheries management organisation established to conserve and manage tuna and other highly migratory fish stocks across the western and central area ...
, the Inter-American Tropical Tuna Commission
, motto =
, formation =
, type = tuna regional fishery management organisation
, status = International organization
, purpose = Fisheries management
, headquarters = La Jolla, San Diego, United Sta ...
, the Indian Ocean Tuna Commission
, motto =
, formation =
, type = International organization
, status =
, purpose = Fisheries
, headquarters = Victoria, Seychelles
, membership = 32 state me ...
, the , and the Commission for the Conservation of Southern Bluefin Tuna
The Commission for the Conservation of Southern Bluefin Tuna (CCSBT) is a Regional fisheries management organisation and international organization with the purpose of managing the stocks of the critically endangered Southern bluefin tuna.
The s ...
. The five gathered for the first time in Kobe
Kobe ( , ; officially , ) is the capital city of Hyōgo Prefecture Japan. With a population around 1.5 million, Kobe is Japan's seventh-largest city and the third-largest port city after Tokyo and Yokohama. It is located in Kansai region, whic ...
, Japan
Japan ( ja, 日本, or , and formally , ''Nihonkoku'') is an island country in East Asia. It is situated in the northwest Pacific Ocean, and is bordered on the west by the Sea of Japan, while extending from the Sea of Okhotsk in the north ...
in January 2007. Environmental organizations made submissions on risks to fisheries and species. The meeting concluded with an action plan drafted by some 60 countries or areas. Concrete steps include issuing certificates of origin to prevent illegal fishing
Illegal, unreported and unregulated fishing (IUU) is an issue around the world. Fishing industry observers believe IUU occurs in most fisheries, and accounts for up to 30% of total catches in some important fisheries.
Illegal fishing takes pl ...
and greater transparency in the setting of regional fishing quotas. The delegates were scheduled to meet at another joint meeting in January or February 2009 in Europe.
In 2010, Greenpeace
Greenpeace is an independent global campaigning network, founded in Canada in 1971 by Irving Stowe and Dorothy Stowe, immigrant environmental activists from the United States. Greenpeace states its goal is to "ensure the ability of the Earth t ...
International added the albacore, bigeye tuna, Pacific bluefin tuna
The Pacific bluefin tuna (''Thunnus orientalis'') is a predatory species of tuna found widely in the northern Pacific Ocean, but it is migratory and also recorded as a visitor to the south Pacific.
In the past it was often included in '' T. thyn ...
, Atlantic bluefin tuna
The Atlantic bluefin tuna (''Thunnus thynnus'') is a species of tuna in the family Scombridae. It is variously known as the northern bluefin tuna (mainly when including Pacific bluefin as a subspecies), giant bluefin tuna or individuals exceed ...
, southern bluefin tuna
The southern bluefin tuna (''Thunnus maccoyii'') is a tuna of the family (biology), family Scombridae found in open southern Hemisphere waters of all the world's oceans mainly between 30th parallel south, 30°S and 50th parallel south, 50°S, to ...
, and yellowfin tuna
The yellowfin tuna (''Thunnus albacares'') is a species of tuna found in pelagic waters of tropical and subtropical oceans worldwide.
Yellowfin is often marketed as ahi, from the Hawaiian language, Hawaiian , a name also used there for the closel ...
to its seafood red list, which are fish "commonly sold in supermarkets around the world, and which have a very high risk of being sourced from unsustainable fisheries."
Bluefin tuna have been widely accepted as being severely overfished
Overfishing is the removal of a species of fish (i.e. fishing) from a body of water at a rate greater than that the species can replenish its population naturally (i.e. the overexploitation of the fishery's existing fish stock), resulting in the ...
, with some stocks at risk of collapse. According to the International Seafood Sustainability Foundation
International Seafood Sustainability Foundation (ISSF) was formed in 2009 as a global, non-profit partnership among the tuna industry, scientists and World Wide Fund for Nature. The multistakeholder group states its mission is "to undertake scien ...
(a global, nonprofit partnership between the tuna industry, scientists, and the World Wide Fund for Nature
The World Wide Fund for Nature Inc. (WWF) is an international non-governmental organization founded in 1961 that works in the field of wilderness preservation and the reduction of human impact on the environment. It was formerly named the Wor ...
), Indian Ocean yellowfin tuna, Pacific Ocean (eastern and western) bigeye tuna, and North Atlantic albacore tuna are all overfished. In April 2009, no stock of skipjack tuna
The skipjack tuna (''Katsuwonus pelamis'') is a medium-sized perciform fish in the tuna family, Scombridae. It is otherwise known as the balaya (Sri Lanka), bakulan/kayu (North Borneo), tongkol/aya (Malay Peninsula/Indonesia), aku (Hawaii), cakal ...
(which makes up roughly 60% of all tuna fished worldwide) was considered to be overfished.
The BBC #REDIRECT BBC #REDIRECT BBC #REDIRECT BBC
Here i going to introduce about the best teacher of my life b BALAJI sir. He is the precious gift that I got befor 2yrs . How has helped and thought all the concept and made my success in the 10th board ex ...
documentary '' South Pacific'', which first aired in May 2009, stated that, should fishing in the Pacific continue at its current rate, populations of all tuna species could collapse within five years. It highlighted huge Japanese and European tuna fishing vessels, sent to the South Pacific international waters after overfishing their own fish stocks to the point of collapse.
A 2010 tuna fishery assessment report, released in January 2012 by the Secretariat of the Pacific Community, supported this finding, recommending that all tuna fishing should be reduced or limited to current levels and that limits on skipjack fishing be considered.
Research indicates that increasing ocean temperatures are taking a toll on the tuna in the Indian Ocean, where rapid warming of the ocean has resulted in a reduction of marine phytoplankton
Phytoplankton () are the autotrophic (self-feeding) components of the plankton community and a key part of ocean and freshwater ecosystems. The name comes from the Greek words (), meaning 'plant', and (), meaning 'wanderer' or 'drifter'.
Ph ...
. The bigeye tuna catch rates have also declined abruptly during the past half century, mostly due to increased industrial fisheries, with the ocean warming adding further stress to the fish species.
See also
* Environmental impact of fishing
The environmental impact of fishing includes issues such as the availability of fish, overfishing, fisheries, and fisheries management; as well as the impact of industrial fishing on other elements of the environment, such as bycatch. These is ...
* Got Mercury?
* List of tuna dishes
This is a list of notable tuna dishes, consisting of foods and dishes prepared using tuna as a primary ingredient. Tuna is a versatile ingredient that is used in a variety of dishes, including entrees, sandwiches, sushi, salads, appetizers, soups ...
* Natal homing
Natal homing, or natal philopatry, is the homing process by which some adult animals return to their birthplace to reproduce. This process is primarily used by aquatic animals, such as sea turtles and Pacific salmon. Scientists believe that the m ...
References
Further references
* Clover, Charles. 2004. '' The End of the Line: How Overfishing Is Changing the World and What We Eat''. Ebury Press, London.
* FAO
The Food and Agriculture Organization of the United Nations (FAO)french: link=no, Organisation des Nations unies pour l'alimentation et l'agriculture; it, Organizzazione delle Nazioni Unite per l'Alimentazione e l'Agricoltura is an intern ...
: Species Catalog Vol. 2 Scombrids of the World. FAO Fisheries Synopsis No. 125, Volume 2. FIR/S125 Vol. 2.
* FAO
The Food and Agriculture Organization of the United Nations (FAO)french: link=no, Organisation des Nations unies pour l'alimentation et l'agriculture; it, Organizzazione delle Nazioni Unite per l'Alimentazione e l'Agricoltura is an intern ...
: Review of the state of world marine fishery resources
Tuna and tuna-like species – Global, 2005
Rome.
* Majkowski, Jacek (1995
In: ''Review of the state of world marine fishery resources'', FAO Fisheries technical paper 457, FAO, Rome. .
* Majkowski J, Arrizabalaga H, Carocci F and Murua H (2011
"Tuna and tuna-like species"
In: ''Review of the state of world marine fishery resources'', pages 227–244, FAO Fisheries technical paper 569, FAO, Rome. .
* Standard of Identity for Canned Tuna (United States), Code of Federal Regulations: 21 CFR 161.190 – Canned tuna.
* Viñas J and Tudela S (2009
"A validated methodology for genetic identification of tuna species (genus ''Thunnus'')"
''PLoS One'', 4(10): e7606.
Further reading
Bluefin Tuna, Chinese Cobra and Others Added to Red List of Threatened Species
Scientific American, 18 November 2014
How Hot Tuna (and Some Sharks) Stay Warm
National Science Foundation, 27 October 2005
{{Authority control
Commercial fish
Oily fish
Scombridae
Sport fish