Molecular genetic analyses strongly suggest that Greenland cod is not different from Pacific cod, Gadus macrocephalus - Gadus ogac is then a junior synonym of G. macrocephalus. Nevertheless, ITIS still lists Gadus ogac as a valid name.
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Cod is the common name for the demersal fish genus Gadus, belonging to the family Gadidae. Cod is also used as part of the common name for a number of other fish species, and one species that belongs to genus Gadus is commonly not called cod (Alaska pollock, Gadus chalcogrammus). The two most common species of cod are the Atlantic cod (Gadus morhua), which lives in the colder waters and deeper sea regions throughout the North Atlantic, and the Pacific cod (Gadus macrocephalus), found in both eastern and western regions of the northern Pacific. Gadus morhua was named by Linnaeus in 1758.
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The Alaska pollock or walleye pollock (Gadus chalcogrammus) is a marine fish species of the cod genus Gadus and family Gadidae. It is a semi-pelagic schooling fish widely distributed in the North Pacific, with largest concentrations found in the eastern Bering Sea.
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One member of the genus Gadus is also commonly referred to as pollock: the Alaska pollock or walleye pollock (Gadus chalcogrammus), including the form known as the Norway pollock. They are also members of the family Gadidae but not members of the genus Pollachius.
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The Atlantic cod is one of three cod species in the genus Gadus along with Pacific cod and Greenland cod. A variety of fish species are colloquially known as cod, but they are not all classified within the Gadus, though some are in the Atlantic cod family, Gadidae.
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It is found in huge schools. Molecular genetic analyses strongly suggest that Pacific cod and Greenland cod (Gadus ogac) from Greenland–the Arctic Ocean are the same species; G. ogac is then a junior synonym of G. macrocephalus. Nevertheless, ITIS still lists Gadus ogac as a valid name. This change would greatly expand the geographic range of Pacific cod.
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The Atlantic cod, Gadus morhua Cods of the genus Gadus have three rounded dorsal and two anal fins. The pelvic fins are small, with the first ray extended, and are set under the gill cover (i.e. the throat region), in front of the pectoral fins. The upper jaw extends over the lower jaw, which has a well-developed chin barbel.
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While belonging to the same family as the Atlantic pollock, the Alaska pollock is not a member of the genus Pollachius, but of the cod genus Gadus. Nevertheless, alternative trade names highlighting its placement in the cod genus, such as "snow cod", "bigeye cod", or direct deductions from the scientific names such as "copperline cod" (gadus meaning 'cod', from meaning 'copper', and meaning 'line') or "lesser cod" (from the synonymous taxon Gadus minor) have yet to find widespread acceptance. The National Oceanic and Atmospheric Administration even states that "[the common name] might never change, as common names are separate from scientific names". In addition, Norwegian pollock (Theragra finnmarchica), a rare fish of Norwegian waters, is likely the same species as the Alaska pollock.
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Fish from the Barents Sea that was initially described as own species Theragra finnmarchica (Norway pollock), but is now known to be genetically identical to Gadus chalcogrammus (Alaska pollock). Very small populations of fish genetically identical to Gadus chalcogrammus are found in the Barents Sea waters of northern Norway and Russia. This fish was initially described as its own species under the taxon Theragra finnmarchica by Norwegian zoologist Einar Koefoed in 1956. The common name used for the fish was "Norway pollock".
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Atlantic cod (Gadus morhua) live in the colder waters and deeper sea regions throughout the North Atlantic. Pacific cod (Gadus macrocephalus) is found in both eastern and western regions of the Pacific."Cod", Encyclopædia Britannica online 2008 Atlantic cod divide into several stocks, including the Arcto-Norwegian, North Sea, Faroe, Iceland, East Greenland, West Greenland, Newfoundland, and Labrador stocks. There seems to be little interchange between the stocks, although migrations to their individual breeding grounds may involve distances of or more.
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Cod fisheries are fisheries for cod. Cod is the common name for fish of the genus Gadus, belonging to the family Gadidae, and this article is confined to three species that belong to this genus: the Atlantic cod, the Pacific cod and the Greenland cod. Although there is a fourth species of the cod genus Gadus, Alaska pollock, it is commonly not called cod and therefore currently not covered here. Cod are demersal fish found in huge schools confined to temperate waters in the northern hemisphere.
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Araneus gadus is a species of orb weaver in the spider family Araneidae. It is found in the United States. The scientific name of the species was first validly published in 1973 by Herbert Walter Levi.
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NOAA National Centers for Coastal Ocean Science. For example, it provides a sheltered spawning ground for the Pacific herring (Clupea pallasii). Juvenile Atlantic cod (Gadus morhua) hide in eelgrass beds as they grow.Hanson, A. R. (2004).
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In autumn, when many salmon die after spawning, dead fish tend to be consumed more often than live ones, and these are the main food for Steller's sea eagles that overwinter in inland rivers with unfrozen waters. On Hokkaido, eagles are attracted by abundant Pacific cod (Gadus macrocephalus) which peak in the Rausu Sea and the Nemuro Straits in February. This resource supports an important commercial fishery which in turn helps to support eagles. Alaska pollock (Gadus chalcogrammus), along with the cod, is the most important food source for wintering eagles in Japan.
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In 2014, the U.S. Food and Drug Administration revealed that the official scientific name for the fish was changed from Theragra chalcogramma back to its original taxon Gadus chalcogrammus, highlighting its close genetic relationship to the other species of the cod genus Gadus. Alaska pollock was long put in its own genus, Theragra, and classified as Theragra chalcogramma, but more recent research has shown it is rather closely related to the Atlantic cod and should therefore be moved back to Gadus, where it was originally placed. The change of the official scientific name was followed by a discussion to change the common name as well, to highlight the fish as a member of the cod genus. The common names "Alaska pollock" and "walleye pollock", both used as trade names internationally, are considered misleading by scientific and trade experts, as the names do not reflect the scientific classification.
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Publication for the 30th anniversary of the foundation of the National Cooperative Association of Squid Processors. In Norwegian waters, R. moelleri is preyed upon by haddock (Melanogrammus aeglefinus) and Atlantic cod (Gadus morhua).Grieg, J.A. 1930. The Cephalopod Fauna of Svalbard.
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The Greenland cod (Gadus ogac), commonly known also as ogac, is a species of ray-finned fish in the cod family, Gadidae. Genetic analysis has shown that it may be the same species as the Pacific cod (Gadus macrocephalus). It is a bottom-dwelling fish and is found on the continental shelf in the Arctic Ocean and northwestern Atlantic Ocean, its range extending from Alaska to West Greenland, then southwards along the Canadian coast to the Gulf of St. Lawrence and Cape Breton Island. It is a commercially harvested food fish, but landings have been greatly reduced in recent years.
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Pollock roe, also pollack roe, (also known as myeongnan-jeot and tarako) is the roe of Alaska pollock (Gadus chalcogrammus) which, despite its name, is a species of cod. Salted pollock roe is a popular culinary ingredient in Korean, Japanese, and Russian cuisines.
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Arctic Cod Aquatic species. Fisheries and Oceans Canada. is a fish of the cod family Gadidae, related to the true cod (genus Gadus). Another fish species for which both the common names Arctic cod and polar cod are used is Arctogadus glacialis.
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Fossil marine fish from the Norwich Crag include genera Chrysophrys sp. (a snapper), Acipenser (sturgeon) and Notidanus (a cow shark), and species Platax woodwardi (a batfish), Gadus morhua (Atlantic cod), Rhinoptera woodwardi (a cownose ray) and Raja clavata (thornback ray).Newton, ET (1891). The Vertebrata of the Pliocene Deposits of Britain.
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The nominate race feeds primarily on fish such as Gadus spp. and Arctic cod (Boreogadus saida), as well as the pelagic amphipod Parathemisto libellula. Other fish such as capelin (Mallotus villosus) and Myoxocephalus spp., as well as other crustaceans, polychaetes, and a few molluscs, are found in their diet but in relatively low numbers.
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Otolith elemental fingerprinting for stock identification of Atlantic cod (Gadus morhua). Canadian journal of fisheries and aquatic science 51: 1942-1950 It has also been used to determine the migratory patterns of anadromous whitefish.Halden, N.M. and L.A. Friedrich. 2008. Trace-element distribution in fish otoliths: natural markers of life histories, environmental conditions and exposure to tailings effluence.
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The Murray cod (Maccullochella peelii) is a large Australian predatory freshwater fish of the genus Maccullochella in the family Percichthyidae.Dianne J. Bray & Vanessa J. Thompson (2011) Murray Cod, Maccullochella peelii. Fishes of Australia. Retrieved 29 August 2014 Although the species is called a cod in the vernacular, it is not related to the Northern Hemisphere marine cod (Gadus) species.
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Sebastidae is a family of marine fish in the order Scorpaeniformes. Their common names include rockfishes, rock perches, ocean perches, sea perches, thornyheads, scorpionfishes, sea ruffes and rockcods. Despite the latter name, they are not closely related to the cods in the genus Gadus, nor the rock cod, Lotella rhacina. Not all authorities recognise this family as distinct from Scorpaenidae.
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The rock cod (Lotella rhacina) is a temperate fish found off the coasts of southeastern Australia, Tasmania, the Great Australian Bight and northwards up the southwestern Australia coasts. They are also found around the coasts of New Zealand and California. They belong to the family Moridae and are not related to the true cods (genus Gadus). They are also known as beardie in Australia.
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Arctogadus glacialis, known also with ambiguous common names Arctic codGadiform fishes of the World (Order Gadiformes) An annotated and illustrated catalogue of Cods, Hakes, Grenadiers and other gadiform fishes known to date. FAO Fisheries Synopsis No. 125, Volume 10. 1990. and polar cod,Polar Cod University of Guelph. is an Arctic species of fish in the cod family Gadidae, related to the true cod (genus Gadus).
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Common characteristics include the positioning of the pelvic fins (if present), below or in front of the pectoral fins. Gadiformes are physoclists, which means their gas bladders do not have a pneumatic duct. The fins are spineless. Gadiform fish range in size from the codlets, which may be as small as in adult length, to the Atlantic cod, Gadus morhua, which reaches up to .
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The fisheries have been and still are the most important economic activity in Hovden. Several different fisheries are important, but the most significant are the winter- fisheries between Christmas and Easter. These fisheries are also known under the name Lofotfisket. The Cod, gadus morhua migrate from the Barents Sea to spawn along the coast of Lofoten and have to pass Vesterålen on its way.
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Genetic analyses have shown that the fish is genetically identical to the Alaska pollock. It is therefore considered to be conspecific with the Pacific species and is attributed to Gadus chalcogrammus. The history of the species in the Barents Sea is unknown. The initial specification as an own species by Koefoed was based on two specimens landed in Berlevåg, northern Norway, in 1932 (hence the Norwegian name, ).
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Bell, the Report's author, subsequently stated that political pressure by the DFO within COSEWIC was what accounted for the difference. In 1998 in a book Bell argued (Bell, K. N. I. 1998. An object lesson for demersal African fisheries from the collapse of Canadian Atlantic Cod (Gadus morhua). In L. Coetzee, J. Gon, & C. Kulongowski (Eds), African Fishes and Fisheries - diversity and utilisation. Vol.
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The small-headed cod or long-finned cod (Lepidion microcephalus) is a deepwater fish belonging to the morid cod family (Moridae), and related to the true cods (genus Gadus). It is found in the Tasman Sea, including Bass Strait, and is commercially harvested by both Australia and New Zealand. It has been found on the continental shelf, but typically its depth range is from . It grows to in total length.
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The Western Gulf of Maine Closure Area (WGoMAC) was established in 1998 in response to the decreasing Atlantic Cod (Gadus morhua) stock. WGoMAC is located off the shores of Massachusetts, New Hampshire, and Maine and is approximately . It is rectangular and runs in straight lines from 42° 15' to 43° 15' North, and 69° 55' to 70° 15' West. It is a year long closed area that prevents groundfish fishing.
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The East Siberian cod (Arctogadus borisovi) also known as the toothed cod, is an Arctic fish closely similar to the Arctic cod Arctogadus glacialis and also related to true cods (genus Gadus). It has been differentiated in appearance from the Arctic cod by having pronounced chin barbel. Their sides and back are dark olive and the belly are light grey with dark spots. They may grow up to 60 cm.
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Keenleyside, M.H.A., and Prince, C. (1976) Spawning-site selection in relation to parental care of eggs in Aequidens paraguayensis (Pisces: Cichlidae). Canadian Journal of Zoology 54: 2135-2139. In one laboratory study, Atlantic cod (Gadus morhua) given access to an operant feeding machine learned to pull a string to get food. The researchers had also tagged the fish by threading a bead in front of their dorsal fin.
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By 2006, 54 individuals had been recorded. Sequencing of mitochondrial DNA of two specimens of Theragra finnmarchica and 10 Theragra chalcogramma (today: Gadus chalcogrammus) revealed no significant genetic differences, leading Ursvik et al. to suggest that T. finnmarchica and T. chalcogramma are the same species. An analysis of a much larger sample size (44 T. finnmarchica and 20 T. chalcogramma) using both genetic and morphological methods led to similar conclusions.
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These analyses also suggest that T. finnmarchica is a near relative of the Atlantic cod, and that both Alaska and Norway pollock should be moved to genus Gadus. Norway pollock (Theragra finnmarchica) was listed as Near Threatened in the 2010 Norwegian Red List for Species based on criteria D1: "Very small or geographically very restricted population: Number of mature individuals". It is currently not listed in the IUCN Red List.
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A. elongatus aggregates during the winter. In the Russian Federation, its spawning season has been reported to occur from April to June. It is preyed on by Gadus macrocephalus (the Pacific cod), Hemitripterus villosus, and Hexagrammos otakii. Its own diet consists of bony fish such as Engraulis japonicus and Sardinops sagax, crabs such as Erimacrus isenbeckii, Oregonia gracilis and spider crabs, euphausiids such as Euphausia pacifica, as well as cephalopods, polychaetes, and debris.
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Gadimyxa atlantica is a species of parasitic myxozoan. Together with G. arctica and G. sphaerica, they infect Gadus morhua and Arctogadus glacialis by developing coelozoically in bisporic plasmodia in their urinary systems. These 3 species' spores exhibit two morphological forms: wide and subspherical, being both types bilaterally symmetrical along the suture line. The wide spores have a mean width ranging from 7.5-10μm, respectively, while the subspherical ones range from 5.3-8μm in mean width.
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Gadimyxa sphaerica is a species of parasitic myxozoan. Together with G. arctica and G. atlantica, they infect Gadus morhua and Arctogadus glacialis by developing coelozoically in bisporic plasmodia in their urinary systems. These 3 species' spores exhibit two morphological forms: wide and subspherical, being both types bilaterally symmetrical along the suture line. The wide spores have a mean width ranging from 7.5-10μm, respectively, while the subspherical ones range from 5.3-8μm in mean width.
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Gadimyxa arctica is a species of parasitic myxozoan. Together with G. atlantica and G. sphaerica, they infect Gadus morhua and Arctogadus glacialis by developing coelozoically in bisporic plasmodia in their urinary systems. These 3 species' spores exhibit two morphological forms: wide and subspherical, being both types bilaterally symmetrical along the suture line. The wide spores have a mean width ranging from 7.5-10μm, respectively, while the subspherical ones range from 5.3-8μm in mean width.
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The saffron cod (Eleginus gracilis) is a commercially harvested fish closely related to true cods (genus Gadus). It is dark grey-green to brown, with spots on its sides and pale towards the belly. It may grow to 60 cm and weigh up to 1.3 kg. Its range spans the North Pacific, from Korea and the Sea of Okhotsk in the west to the northern Gulf of Alaska and eastern Banks Island in the east.
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In the interior there is a relict lake, Lake Mogil'noe (or Molginoye), which is separated from Kildin Strait by an isthmus through which seawater filters that replenishes the lake. The brackish lake holds a unique species of cod (Gadus morhua kildinensis) that has adapted to it. The island is long by and wide at the widest part. Kildin Strait, which separates it from the mainland, is long and varies in width from to about .
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The tadpole cod (Guttigadus globosus) is a deepwater fish found in the oceanic islands off New Zealand and in the mid South Atlantic at depths ranging from 1200 to 1600 m. The tadpole cod is a member of the family Moridae, the morid cods, related to the true cods (of genus Gadus, family Gadidae). Like the familiar Atlantic cod, it has small whiskers (barbels) on its mouth. Specimens have been measured up to 18 cm.
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ICES, published in the ICES Report AFWG 2007, ACFM:16. Estimation method: Standard VPA. Gadus morhua (Atlantic cod) The Northeast Atlantic is the world's largest population of cod. By far the largest part of this population is the North- East Arctic Cod, as it is labelled by the ICES, or the Arcto-Norwegian cod stock, also referred to as skrei, a Norwegian name meaning something like "the wanderer", distinguishing it from coastal cod.
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Haisborough Sands and its surrounding shoals are known to be spawning grounds for Sand eels Ammodytes, Lemon sole Microstormus Kitt and sole Solea solea. The sands also provide nursery grounds for Cod Gadus morhua, Herring Clupea harengus, Mackerel Scomber scombrus, Sole, Lemon sole and Plaice Pleuronectes platessa. There are small numbers of Harbour porpoise regularly observed within the boundaries of the sands. The common seals Phoca vitulina which are resident in the Wash are occasionally observed in this area.
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The Pacific cod, Gadus macrocephalus, is a species of ray-finned fish in the family Gadidae. It is a bottom-dwelling fish found in the northern Pacific Ocean, mainly on the continental shelf and upper slopes, to depths of about . It can grow to a length of a meter or so and is found in large schools. It is an important commercial food species and is also known as gray cod or grey cod, and grayfish or greyfish.
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At various times in the past, taxonomists included many species in the genus Gadus. Most of these are now either classified in other genera, or have been recognized as forms of one of three species. All these species have a number of common names, most of them ending with the word "cod", whereas other species, as closely related, have other common names (such as pollock and haddock). However, many other, unrelated species also have common names ending with cod.
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In 1977, The Berelson Company of San Francisco, California, US, working with Sugiyo, introduced them internationally. Kanikama is still their common name in Japan, but internationally they are marketed under names including Krab Sticks, Ocean Sticks, Sea Legs and Imitation Crab Sticks. Legal restrictions now prevent them from being marketed as "Crab Sticks" in many places, as they usually do not have crab meat. Most crab sticks today are made from Alaska pollock (Gadus chalcogrammus) of the North Pacific Ocean.
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It is home to a wide range of species due to the nutrient-rich waters. This includes benthic and pelagic fish, such as capelin (Mallotus villosus) and cod (Gadus morhua). This attracts migratory seals such as harp (Pagophilus groenlandicus) and hooded seal (Cystophora cristata) and ringed (Pusa hispida) and bearded seal (Erignathus barbatus). The bay is home during spring time to bowhead (Balaena mysticetus) and humpback (Megaptera novaeangliae) whales, as well as Pilot (Globicephala melas), killer whales (Orcinus orca) and narwhal (Monodon monoceros).
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Concerns about the environmental impact of these compounds has increased since the 1990s. These surfactants have a mild to medium estrogenic function.Comparison of protein expression in plasma from nonylphenol and bisphenol A-exposed Atlantic cod (Gadus morhua) and turbot (Scophthalmus maximus) by use of SELDI-TOF. Larsen Bodil K; Bjornstad Anne; Sundt Rolf C; Taban Ingrid C; Pampanin Daniela M; Andersen Odd Ketil International Research Institute of Stavanger (IRIS) AS, Mekjarvik 12, N-4070 Randaberg, Norway Aquatic toxicology (Amsterdam, Netherlands) (2006), 78 Suppl 1 S25-33.
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Dried Capelin (Mallotus villosus), or ammassat Because the majority of Greenland is covered by permanent glaciers, the sea is the source for most food.Kleivan, "Greenland Eskimo," 522 Seafood dishes include various fishes (often smoked), mussels, and shrimp. Ammassat or capelin is commonly eaten and can easily be dried. Atlantic halibut, redfish, deepwater redfish, Greenland halibut, and lumpfish are fished from the west coast, as are Greenland cod (Gadus ogac) and shorthorn sculpin (Myoxocephalus scorpius), but these two are eaten only as a last resort.
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Canadian Atlantic Cod (Gadus morhua), are cold water fish, which weigh 2 to 3 kg in the wild. Atlantic Cod were originally found in the Atlantic Ocean, along the borders of both Canada and England and all the way down to the southern United States. Heavy fishing in these areas, in the late 1800s and early 1900s led to a massive decline in Cod population. Today, they are grown in onshore temperature controlled, seawater tanks as eggs and eventually taken to sea cages when more developed.
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Cobb was a well- known "professional" naturalist of his day and his reputation was based on his keen knowledge of the commercial fisheries industry which was reflected in his many publications. He was a skilled compiler of fisheries catch statistics, and he produced well-received books on the fisheries of both Pacific salmon, Oncorhynchus spp., and Pacific cod, Gadus macrocephalus. Cobb's position as Dean of the College of Fisheries at the University of Washington emphasized his role as a leading national expert on fisheries.
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SeaChoice has four main themes of work: # Seafood Progress – an online service for Canadian retailers to assess and report on their performance around sustainable seafood commitments and procurement. # Priority Species – species produced in Canada or imported into Canada that enter the supply chain via fisheries and aquaculture Atlantic cod (Gadus morhua) is one of 14 SeaChoice priority species for conservation and management.operations that have sustainability challenges for which we are seeking solutions. # Eco-labels – their proactive engagement with eco-label initiatives to improve labelling standards and ensure certifications remain credible.
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Their growth rate is high, especially in their early life phases but slows as they attain sexual maturity. Their life cycle is thought to take just over a single year to complete, based on statolith analysis but the larger squid of over 500mm mantle length are thought to be 18 months to two years old. T.sagittatus juvenile The European flying squid preys on fish, crustaceans and cephalopods. In the more northerly part of its range small Atlantic herring (Clupea harenqus) are the main prey as are Atlantic cod (Gadus morhua).
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Similarly, on Great Island in Newfoundland, 25% of the stomach contents were fish but 68% of regurgitants were fish. The most regularly reported fish eaten in Nova Scotia and Newfoundland were capelin (Mallotus villosus), Atlantic cod (Gadus morrhua), Atlantic tomcod (Microgadus tomcod), Atlantic mackerel (Scomber scombrus), Atlantic herring (Clupea harengus) and sand lance (Ammodytes hexapterus). Other prey often includes various squid, Jonah crabs (Cancer borealis), rock crabs (Cancer irroratus), sea urchins, green crabs (Carcinus maenas), starfish (Asterias forbesi and Asterias rubens) and other echinoderms, crustaceans and mollusks when they come across the opportunity.
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Peacock, E., Derocher, A. E., Thiemann, G. W., & Stirling, I. (2011). Conservation and management of Canada’s polar bears (Ursus maritimus) in a changing Arctic 1 1 This review is part of the virtual symposium “Flagship Species–Flagship Problems” that deals with ecology, biodiversity and management issues, and climate impacts on species at risk and of Canadian importance, including the polar bear (Ursus maritimus), Atlantic cod (Gadus morhua), Piping Plover (Charadrius melodus), and caribou (Rangifer tarandus). Canadian Journal of Zoology, 89(5), 371-385.Ferguson, S. H., Higdon, J. W., & Westdal, K. H. (2012).
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The direct selection for biological traits through fishery practices is the result of fishery management regulations, and gear restrictions and selectivities. The most obvious artificial selection for traits through management legislation can be observed in the imposed regulations on size, sex, seasonality, and locations. Catch size regulations vary with specificity to the targeted species and is often used to prevent exploitation during a specific part of the life cycle for the organism. Such regulations arose in response to the effects of FIE observed by the fisheries of Atlantic Cod (Gadus morhua).
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Aega psora is a facultive parasite which temporarily attaches itself to its host and is able to survive independently. It probably spends the rest of the time resting on the seabed. It has been found as an external parasite on the Atlantic cod (Gadus morhua), the Greenland shark (Somniosus microcephalus), a shark in the genus Squalus, the common skate (Raja batis), the thorny skate (Amblyraja radiata) and the barndoor skate (Dipturus laevis). Large numbers have also been found in the stomach of a Greenland shark, though whether living as a parasite or as a commensal is unclear.
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This interaction may not always be negative. Studies have shown that certain invasive species have begun to shift cascades; and as a consequence, ecosystem degradation has been repaired. An example of a cascade in a complex, open- ocean ecosystem occurred in the northwest Atlantic during the 1980s and 1990s. The removal of Atlantic cod (Gadus morhua) and other ground fishes by sustained overfishing resulted in increases in the abundance of the prey species for these ground fishes, particularly smaller forage fishes and invertebrates such as the northern snow crab (Chionoecetes opilio) and northern shrimp (Pandalus borealis).
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Along the west side of the watershed, steep hills rise abruptly to highland plateaus (the Cape Breton Highlands) at elevations of . Extensive wetland and bog deposits occur in the upper reaches of the watershed, specifically in the Cape Breton Highlands, the Boisdale Hills and the East Bay Hills. Large wetlands in the highland portions of the Middle River and Baddeck River serve to store and release water slowly to these major sub-watersheds within the Bras d'Or Lake. The most common fish of the boreal group found in the area are cod (Gadus morhua), white hake (Urophycis tenuis) and winter skate (Raja ocellatus).
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Several genes involved in mammalian nociception, such as brain-derived neurotrophic factor (BDNF) and the cannabinoid CB1 receptor are regulated in the fish brain after a nociceptive event. Somatosensory evoked potentials (SEPs) are weak electric responses in the CNS following stimulation of peripheral sensory nerves. These further indicate there is a pathway from the peripheral nociceptors to higher brain regions. In goldfish, rainbow trout, Atlantic salmon (Salmo salar) and Atlantic cod (Gadus morhua), it has been demonstrated that putatively non-noxious and noxious stimulation elicit SEPs in different brain regions, including the telencephalon which may mediate the co-ordination of pain information.
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1 for some of the 10 management (sub) units addressed in the reportStatus of Atlantic Cod, Gadus morhua, in Canada that COSEWIC had commissioned from Dr. K.N.I. Bell. That contradiction between the report and the listing reflected political pressure from the DFO; such bureaucratic pressure had been evident through three years of drafts. The 1998 designation followed on from a deferral in 1997 and bureaucratic tactics including what one COSEWIC insider characterised as "a plan to make it late".COSEWIC: armpit-length committee Press interest before the 1998 meeting had, however, likely deterred a further deferral.
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White fish (Atlantic cod) White fish fillet (halibut – on top) contrasted with an oily fish fillet (salmon – at bottom) Whitefish or white fish is a fisheries term for several species of demersal fish with fins, particularly Atlantic cod (Gadus morhua), whiting (Merluccius bilinearis), haddock (Melanogrammus aeglefinus), hake (Urophycis), pollock (Pollachius), and others. Whitefish (Coregonidae) is also the name of several species of Atlantic freshwater fish. Whitefish live on or near the seafloor, and can be contrasted with the oily or pelagic fish which live in the water column away from the seafloor. Whitefish do not have much oil in their tissue, and have flakier white or light-coloured flesh.
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Handbook of North American Birds Volume VI: Diurnal Raptors (Part 1). Yale University Press. The same Norwegian study coincided that another eagle when trying to fly with an Atlantic cod (Gadus morhua) weighing about , the fish was quickly dropped as it was apparently deemed too heavy. The widely reported case of a white-tailed eagle carrying off a 3.5-year-old girl in Norway flight by the back of her dress only to drop her mostly unharmed below the eagle's eyrie, which was included in the Guinness Book of World Records, is considered most likely to be apocryphal since she weighed approximately , far too heavy for any living eagle to lift in flight.
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The distinction between demersal species of fish and pelagic species is not always clear cut. The Atlantic cod (Gadus morhua) is a typical demersal fish, but can also be found in the open water column, and the Atlantic herring (Clupea harengus) is predominantly a pelagic species but forms large aggregations near the seabed when it spawns on banks of gravel. Two types of fish inhabit the demersal zone: those that are heavier than water and rest on the seabed, and those that have neutral buoyancy and remain just above the substrate. In many species of fish, neutral buoyancy is maintained by a gas-filled swim bladder which can be expanded or contracted as the circumstances require.
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Gadus morhua (Atlantic cod) range map Cod populations or stocks can differ significantly both in appearance and biology. For instance, the cod stocks of the Baltic Sea are adapted to low-salinity water. Organisations such as the Northwest Atlantic Fishery Organization (NAFO) and ICES divide the cod into management units or stocks; however these units are not always biologically distinguishable stocks. Some major stocks/management units on the Canadian/US shelf are the Southern Labrador-Eastern Newfoundland stock (NAFO divisions 2J3KL), the Northern Gulf of St. Lawrence stock (NAFO divisions 3Pn4RS), the Northern Scotian Shelf stock (NAFO divisions 4VsW), which all lie in Canadian waters, and the Georges Bank and Gulf of Maine stocks in United States waters.
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Thiamine deficiency in eggs results from an unbalanced diet abundant in fatty prey fish, such as young sprat, from which the supply of thiamine is insufficient in proportion to the supply of energy and unsaturated fatty acids for salmon. Relationships between fish stock changes in the Baltic Sea and the M74 syndrome: The M74 syndrome is connected to a weak Atlantic cod (Gadus morhua) stock and strong year classes of sprat in the Baltic Sea. Since the collapse, heavy fishing mortality as well as predation on cod eggs by sprat and food competition between sprat and young-of-the-year cod has inhibited cod recovery. Coincidentally with the decline in the cod stock since 1982, and following the consequent reduction in predation pressure, the sprat stock increased rapidly, and salmon therefore had more food.
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Simpson, M.R., Gauthier, J., Benoît, H.P., MacDonald, D., Hedges, K., Collins, R., Mello, L. & Miri, C. (2016). A pre- COSEWIC assessment of the Common Lumpfish (Cyclopterus lumpus, Linnaeus 1758) in Canadian Atlantic and Arctic waters. Canadian Science Adversary. However, fish were secondary to birds overall in Norway. Per two studies from Sweden, fish were usually the main food unlike in Norway and Finland and could comprise from 51-60% of the diet. Fish were also somewhat dominant in the foods from two studies in Belarus, making up 48.1-53.7% of the diet.Ivanovsky, V.V. (2010). White-tailed eagle Haliaeetus albicilla in the Byelorussian Poozerie: materials on the biology of the species within the range. Russian Ornithological Journal, 19: 1876-1887. Fish similarly were important to nesting eagles in Hokkaido, where 54% of 533 prey items were fish, led by the Alaska pollock (Gadus chalcogrammus) at 18.4%.
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