The Chinook salmon /ʃɪˈnʊk/ (Oncorhynchus tshawytscha) is the largest species in the Pacific salmon genus Oncorhynchus. The common name refers to the Chinookan peoples. Other vernacular names for the species include king salmonQuinnat salmonspring salmon, chrome hog, and Tyee salmon. The scientific species name is based on the Russian common name chavycha (чавыча).Historically, the native distribution of Chinook salmon in North America ranged from the Ventura River in California in the south to Kotzebue Sound in Alaska in the north.In 1967, the Michigan Department of Natural Resources planted Chinook in Lake Michigan and Lake Huron to control the alewife, an invasive species of nuisance fish from the Atlantic Ocean. Alewives then constituted 90% of the biota in these lakes. Coho salmon had been planted the year before and the program was a success.The Chinook is blue-green, red, or purple on the back and top of the head, with silvery sides and white ventral surfaces. It has black spots on its tail and the upper half of its body. Chinook have a Black gum line which is present in both salt and freshwater.[12] Adult fish range in size from 24 to 36 in (61 to 91 cm), but may be up to 58 in (150 cm) in length; they average 10 to 50 lb (4.5 to 22.7 kg), but may reach 130 lb (59 kg). In the Kenai River of Alaska, mature Chinook averaged 16.8 kg (37 lb).[13] The current sport-caught world record, 97.25 lb (44.11 kg), was caught on May 17, 1985, in the Kenai River (Kenai Peninsula, Alaska). The commercial catch world record is 126 lb (57 kg) caught near Rivers InletBritish Columbia, in the late 1970s.Chinook may spend one to eight years in the ocean (averaging from three to four years)[15] before returning to their home rivers to spawn. The salmon also undergo radical morphological changes as they prepare for the spawning event ahead. All salmon lose the silvery blue they had as ocean fish, and their colour darkens, sometimes with a radical change in hue. Salmon are sexually dimorphic, and the male salmon develop canine-like teeth and their jaws develop a pronounced curve or hook, called a “kype“.[16] Studies have shown that larger and more dominant male salmon have a reproductive advantage as female Chinook are often more aggressive toward smaller males.The total North Pacific fisheries harvest of the Chinook salmon in 2010 was some 1.4 million fish, corresponding to 7,000 tonnes; 1.1 million of the fish were captured in the United States, others were divided by Canada and Russia.The worlds’ largest producer and market supplier of the Chinook salmon is New Zealand. Marketed as King salmon, in 2009, New Zealand exported 5,088 tonnes of salmon equating to a value of NZ$61 million in export earnings. For the year ended March 2011, this amount had increased to NZ$85 million.Nine populations of Chinook salmon are listed under the U.S. Endangered Species Act as either threatened or endangered.The Chinook salmon is spiritually and culturally prized among certain First Nations peoples. Many celebrate the first spring Chinook caught each year with “first-salmon ceremonies”. While salmon fishing is still important economically for many tribal communities, the Chinook harvest is typically the most valuable.


Clownfish or anemonefish are fishes from the subfamily Amphiprioninae in the family Pomacentridae. Thirty species are recognized: one in the genus Premnas, while the remaining are in the genus Amphiprion. In the wild, they all form symbiotic mutualisms with sea anemones. Depending on species, anemonefish are overall yellow, orange, or a reddish or blackish color, and many show white bars or patches. The largest can reach a length of 17 cm (6.7 in), while the smallest barely achieve 7–8 cm (2.8–3.1 in).Anemonefish are omnivorous and can feed on undigested food from their host anemones, and the fecal matter from the anemonefish provides nutrients to the sea anemone. Anemonefish primarily feed on small zooplankton from the water column, such as copepods and tunicate larvae, with a small portion of their diet coming from algae, with the exception of Amphiprion perideraion, which primarily feeds on algae.[2][3] They may also consume the tentacles of their host anemone.Anemonefish and sea anemones have a symbiotic, mutualistic relationship, each providing many benefits to the other. The individual species are generally highly host specific, and especially the genera Heteractis and Stichodactyla, and the species Entacmaea quadricolor are frequent anemonefish partners. The sea anemone protects the anemonefish from predators, as well as providing food through the scraps left from the anemone’s meals and occasional dead anemone tentacles, and functions as a safe nest site. In return, the anemonefish defends the anemone from its predators and parasites.[5][6] The anemone also picks up nutrients from the anemonefish’s excrement.[7] The nitrogen excreted from anemonefish increases the number of algae incorporated into the tissue of their hosts, which aids the anemone in tissue growth and regeneration.[3] The activity of the anemonefish results in greater water circulation around the sea anemone,[8] and it has been suggested that their bright coloring might lure small fish to the anemone, which then catches them.[9] Studies on anemonefish have found that they alter the flow of water around sea anemone tentacles by certain behaviors and movements such as “wedging” and “switching”. Aeration of the host anemone tentacles allows for benefits to the metabolism of both partners, mainly by increasing anemone body size and both anemonefish and anemone respiration.In a group of anemonefish, a strict dominance hierarchy exists. The largest and most aggressive female is found at the top. Only two anemonefish, a male and a female, in a group reproduce – through external fertilization. Anemonefish are sequential hermaphrodites, meaning they develop into males first, and when they mature, they become females. If the female anemonefish is removed from the group, such as by death, one of the largest and most dominant males becomes a female. The remaining males move up a rank in the hierarchy.


Sockeye salmon (Oncorhynchus nerka), also called red salmonkokanee salmon, or blueback salmon, is an anadromous species of salmon found in the Northern Pacific Ocean and rivers discharging into it. This species is a Pacific salmon that is primarily red in hue during spawning. They can grow up to 84 cm (2 ft 9 in) in length and weigh 2.3 to 7 kg (5–15 lb). Juveniles remain in freshwater until they are ready to migrate to the ocean, over distances of up to 1,600 km (1,000 mi). Their diet consists primarily of zooplankton. Sockeye salmon are semelparous, dying after they spawn. Some populations, referred to as kokanee, do not migrate to the ocean and live their entire lives in freshwater.Sockeye salmon is the third-most common Pacific salmon species, after pink and chum salmon.[2] Oncorhynchus comes from the Greek ὄγκος (onkos) meaning “barb”, and ῥύγχος (rhynchos) meaning “snout”. Nerka is the Russian name for the anadromous form.[3] The name “sockeye” is an anglicization of suk-kegh (sθə́qəy̓), its name in Halkomelem, the language of the indigenous people along the lower reaches of the Fraser River (one of British Columbia‘s many native Coast Salish languages). Suk-kegh means “red fish”.[4][5]The sockeye salmon is sometimes called red or blueback salmon, due to its color.[5] Sockeye are blue tinged with silver in color while living in the ocean.[3] When they return to spawning grounds, their bodies become red and their heads turn green. Sockeye can be anywhere from 60 to 84 cm (2 ft 0 in–2 ft 9 in) in length and weigh from 2.3 to 7 kg (5–15 lb).[5] Two distinguishing features are their long, serrated gill rakers that range from 30 to 40 in number, and their lack of a spot on their tail or back.Sockeye salmon range as far south as the Columbia River in the eastern Pacific (although individuals have been spotted as far south as the 10 Mile River on the Mendocino Coast of California) and in northern Hokkaidō Island in Japan in the western Pacific. They range as far north as the Bathurst Inlet in the Canadian Arctic in the east and the Anadyr River in Siberia in the west. The farthest inland sockeye salmon travel is to Redfish Lake, Idaho, over 900 miles (1,400 km) from the ocean and 6,500 feet (2,000 m) in elevation.Completely landlocked populations of the same species also are known. Some sockeye live and reproduce in lakes and are commonly called kokanee, which is red-fish name in the Sinixt Interior Salish language and silver trout in the Okanagan language.


Pink salmon or humpback salmon (Oncorhynchus gorbuscha) is a species of anadromous fish in the salmon family. It is the smallest and most abundant of the Pacific salmon. The scientific species name is based on the Russian common name for this species gorbúša (горбуша), which literally means humpie.In the ocean, pink salmon are bright silver fish. After returning to their spawning streams, their coloring changes to pale grey on the back with yellowish-white belly (although some turn an overall dull green color). As with all salmon, in addition to the dorsal fin, they also have an adipose fin. The fish is characterized by a white mouth with black gums, no teeth on the tongue, large oval-shaped black spots on the back, a v-shaped tail, and an anal fin with 13-17 soft rays. During their spawning migration, males develop a pronounced humped back, hence their nickname “humpies”. Pink salmon average 4.8 pounds (2.2 kg) in weight.[1] The maximum recorded size was 30 inches (76 cm) and 15 pounds (6.8 kg).Pink salmon in their native range have a strict two year life cycle, thus odd and even-year populations do not interbreed. In the state of Washington, Pink salmon runs occur on odd years.[3] Adult pink salmon enter spawning streams from the ocean, usually returning to the stream where they originated. Spawning occurs between late June and mid-October, in coastal streams and some longer rivers, and in the intertidal zone or at the mouth of streams if hyporheic freshwater is available. Using her tail, the female digs a trough-shaped nest, called a redd (Scandinavian word for “nest”), in the gravel of the stream bed, where she deposits her eggs. As she expels the eggs, she is approached by one or more males, which fertilize them as they fall into the redd. Subsequently, the female covers the newly deposited zygotes, again with thrusts of her tail, against the gravel at the top of the redd. The female lays from 1,000 to 2,000 eggs in several clutches within the redd, often fertilized by different males. Females guard their redds until death, which comes within days of spawning. In dense populations, a major source of mortality for embryos is superposition of redds by later-spawning fish. The eggs hatch from December to February, depending on water temperature, and the juveniles emerge from the gravel during March and April and quickly migrate downstream to estuaries, at about one-quarter gram in weight. The fish achieve sexual maturity in their second year of life. They return to freshwater in the summer or autumn as two-year-old adults. Pink and chum salmon sometimes interbreed in nature to form the hybrid known as the miko salmon; the hybrids are sterile.Pink salmon are coldwater fish with a preferred temperature range of 5.6 to 14.6 °C, an optimal temperature of 10.1 °C, and an upper incipient lethal temperature of 25.8 °C. The native range of the species is in the Pacific and Arctic coastal waters and rivers, from the Sacramento River in northern California to the Mackenzie River in Canada; and in the west from the Lena River in Siberia to Korea and Honshu in Japan. In North America pink salmon spawn from the Mackenzie River in the Arctic[4] to as far south as tributaries of Puget SoundWashington, although they were also reported in the San Lorenzo River near Santa Cruz, California in 1915[5] and the Sacramento River in northern California in the 1950s.


Salmon /ˈsæmən/ is the common name for several species of ray-finned fish in the family Salmonidae. Other fish in the same family include troutchargrayling and whitefish. Salmon are native to tributaries of the North Atlantic (genus Salmo) and Pacific Ocean (genus Oncorhynchus). Many species of salmon have been introduced into non-native environments such as the Great Lakes of North America and Patagonia in South America. Salmon are intensively farmed in many parts of the world. Typically, salmon are anadromous: they hatch in fresh water, migrate to the ocean, then return to fresh water to reproduce. However, populations of several species are restricted to fresh water through their lives. Folklore has it that the fish return to the exact spot where they hatched to spawn. Tracking studies have shown this to be mostly true. A portion of a returning salmon run may stray and spawn in different freshwater systems; the percent of straying depends on the species of salmon.[1] Homing behavior has been shown to depend on olfactory memory.[2][3] Salmon date back to the Neogene. Salmon eggs are laid in freshwater streams typically at high latitudes. The eggs hatch into alevin or sac fry. The fry quickly develop into parr with camouflaging vertical stripes. The parr stay for six months to three years in their natal stream before becoming smolts, which are distinguished by their bright, silvery colour with scales that are easily rubbed off. Only 10% of all salmon eggs are estimated to survive to this stage. The smolt body chemistry changes, allowing them to live in salt water. While a few species of salmon remain in fresh water throughout their life cycle, the majority are anadromous and migrate to the ocean for maturation: in these species, smolts spend a portion of their out-migration time in brackish water, where their body chemistry becomes accustomed to osmoregulation in the ocean. The salmon spend about one to five years (depending on the species) in the open ocean, where they gradually become sexually mature. The adult salmon then return primarily to their natal streams to spawn. Atlantic salmon spend between one and four years at sea. When a fish returns after just one year’s sea feeding, it is called a grilse in Canada, Britain, and Ireland. Grilse may be present at spawning, and go unnoticed by large males, releasing their own sperm on the eggs.


Lampreys (sometimes inaccurately called lamprey eels) are an ancient extant lineage of jawless fish of the order Petromyzontiformes, placed in the superclass Cyclostomata. The adult lamprey may be characterized by a toothed, funnel-like sucking mouth. The common name “lamprey” is probably derived from Latin lampetra, which may mean “stone licker” (lambere “to lick” + petra “stone”), though the etymology is uncertain.[3] The plural form lamprey is sometimes seen. There are about 38 known extant species of lampreys and five known extinct species.[5] Parasitic carnivorous species are the most well-known, and feed by boring into the flesh of other fish to suck their blood;[6] but only 18 species of lampreys engage in this micropredatory lifestyle.[7][8] Of the 18 carnivorous species, nine migrate from saltwater to freshwater to breed (some of them also have freshwater populations), and nine live exclusively in freshwater. All non-carnivorous forms are freshwater species.[9] Adults of the non-carnivorous species do not feed; they live off reserves acquired as ammocoetes (larvae), which they obtain through filter feeding.Lampreys live mostly in coastal and fresh waters and are found in most temperate regions except those in Africa. Some species (e.g. Geotria australisPetromyzon marinus, and Entosphenus tridentatus) travel significant distances in the open ocean,[10] as evidenced by their lack of reproductive isolation between populations. Other species are found in land-locked lakes. Their larvae (ammocoetes) have a low tolerance for high water temperatures, which may explain why they are not distributed in the tropics. Lamprey distribution may be adversely affected by overfishing and pollution. In Britain, at the time of the Conquest, lampreys were found as far upstream in the River Thames as Petersham. The reduction of pollution in the Thames and River Wear has led to recent sightings in London and Chester-le-Street.Distribution of lampreys may also be adversely affected by dams and other construction projects due to disruption of migration routes and obstruction of access to spawning grounds. Conversely, the construction of artificial channels has exposed new habitats for colonisation, notably in North America where sea lampreys have become a significant introduced pest in the Great Lakes. Active control programs to control lampreys are undergoing modifications due to concerns of drinking water quality in some areas.Adults superficially resemble eels in that they have scaleless, elongated bodies, and can range from 13 to 100 cm (5 to 40 inches) in length. Lacking paired fins, adult lampreys have large eyes, one nostril on the top of the head, and seven gill pores on each side of the head



The Pacific viperfishChauliodus macouni, is a predatory fish that lives in the abyssal depths of the deep sea. In daytime it can be found from 200–5000 m below the ocean surface. At night it swims up into shallower depths of less than 200m where food is more plentiful. Pacific viperfish will mostly eat crustaceans and small fish. They typically reach lengths of up to 1 foot and are considered an example of deep-sea gigantism.According to O’Day (1973) luminescent silhouetting may aid the fish in mating, spacing themselves out as they hunt, maintaining conspecific aggregations, warning potential predators of their own formidable size, or perhaps allowing them to escape from predators by temporarily blinding them. These functions, however, remain speculative.Pacific viperfish can be characterized by its large mouth, long fang-like teeth and long dorsal fin ray (as much as half its body length). They are iridescent dark silver-blue color in life with pale fins. They can also be a light black color with blue fins.As most fish species, the Pacific viperfish has several parasites. In 2018, Susumu Ohtsuka, Dhugal J. Lindsay and Kunihiko Izawa described a new genus and species of pennellid copepodProtosarcotretes nishikawai, from a single ovigerous female infecting a Pacific viperfish collected from the deep-waters of Suruga Bay, Japan. According to the authors, the new genus had the most plesiomorphic states in the first to fourth legs of pennellid copepods.


Fangtooths are beryciform fish of the family Anoplogastridae (sometimes spelled “Anoplogasteridae”) that live in the deep sea. The name is from Greek anoplo meaning “unarmed” and gaster meaning “stomach”. With a circumglobal distribution in tropical and cold-temperate waters, the family contains only two very similar species in one genus, with no known close relatives.While understandably named for their disproportionately large, fang-like teeth and unapproachable visage, fangtooths are actually quite small and harmless to humans: the larger of the two species, the common fangtooth, reaches a maximum length of just 16 cm (6.3 in);[2] the shorthorn fangtooth is less than half this size[3] though currently known only from juvenile specimens.The head is small with a large jaw and appears haggard, riddled with mucous cavities delineated by serrated edges and covered by a thin skin. The eyes are relatively small, set high on the head; the entire head is a dark brown to black and is strongly compressed laterally, deep anteriorly and progressively more slender towards the tail. The fins are small, simple, and spineless; the scales are embedded in the skin and take the form of thin plates. As compensation for reduced eyes, the lateral line is well-developed and appears as an open groove along the flanks.In adults, the largest two fangs of the lower jaw are so long, the fangtooths have evolved a pair of opposing sockets on either side of the brain to accommodate the teeth when the mouth is closed. According to BBC’s Blue Planet, episode “The Deep”, the fangtooth has the largest teeth of any fish in the ocean, proportionate to body size, and are so large, they can never close their mouths. The juveniles are morphologically quite different – unlike the adults, they possess long spines on the head and preoperculum, larger eyes, a functional gas bladder, long and slender gill rakers, much smaller and depressible teeth, and are a light gray in colour. These differences once caused the two life stages to be classed as distinct species, with one in another genusCaulolepis.The pelagic fangtooths are among the deepest-living fish, found as far as 5,000 m (16,000 ft) down.[1] They are more commonly found between 200 and 2,000 m (660 and 6,560 ft), however, and juveniles apparently stay within the upper reaches of this range. They may undergo diel migrations as is common with many deep-sea fish: by day these fish remain in the gloomy depths and towards evening they rise to the upper layers of the water column to feed by starlight, returning to deep water by daybreak. Fangtooths may form small schools or go alone. They are thought to use contact chemoreception to find prey, relying on luck to bump into something edible.The smaller teeth and longer gill rakers of juveniles suggest they feed primarily by filtering zooplankton from the water, while the deeper-living adults target other fish and squid. The fangtooths’ oversized teeth and mouths are a common feature among the miniature beasts of the deep (cf. viperfishesdaggertoothsbristlemouthsbarracudinasanglerfishes), thought to be an advantage in these lean waters where anything encountered (even if it is larger than the fish) must be considered a possible meal. The fangtooths in turn are preyed upon by other large pelagic fish, such as tuna and marlin and some species of sharks.Fangtooths are known to be robust when compared to many other deep-sea fish;[5] they have been kept alive for months in aquariums despite conditions which are significantly different from their usual deep-sea habitat.Fangtooths have planktonic larvae and are assumed to not be egg guarders; spawning frequency and time are not certain, but some activity has been reported from June–August. The juveniles of common fangtooths begin to assume adult form from about 8 cm (3.1 in) in length, at which time they begin to descend into deeper water.[8] Onset of maturity is not known, but common fangtooths are known to be mature at 16 cm (6.3 in). They are probably slow-growing, as are most deep-sea fish.


The Atlantic wolffish (Anarhichas lupus), also known as the seawolfAtlantic catfishocean catfishdevil fishwolf eel (the common name for its Pacific relative), woof or sea cat, is a marine fish of the wolffish family Anarhichadidae. The numbers of the Atlantic wolffish in US waters are rapidly being depleted, most likely due to overfishing and bycatch, and is currently a Species of Concern according to the U.S. National Oceanic and Atmospheric Administration‘s National Marine Fisheries Service. Apart from their unique appearance wolffish are distinguished by the natural antifreeze they produce to keep their blood moving fluidly in their very cold habitat, involvement by both the male and female in brood bearing, and the large size of their eggs. They are also an important factor in controlling green crab and sea urchin populations, which can become overly disruptive to habitats if left unchecked. Wolffish population success is also an important indicator of the health of other bottom-dweller populations, such as Atlantic cod. The Atlantic wolffish has retained the bodily form and general external characteristics of small blennies (Blennioidei). The largest specimen recorded measured 1.5 m (5 ft) long and weighed almost 18 kg (40 lb).[3] Its body is long, subcylindrical in front, compressed in the caudal portion, smooth and slippery, the rudimentary scales being embedded and almost hidden in the skin. Atlantic wolffish vary in color, usually seen as purplish-brown, a dull olive green, or blueish gray.[2] An even dorsal fin extends the whole length of the back, and a similar fin from the vent to the caudal fin, as in blennies. The pectorals are large and rounded and the pelvic fins are entirely absent. Its obtuse, eel-like body type makes the fish swim slowly, undulating from side to side, like an eel. The Atlantic wolffish’s distinguishing feature, from which it gets its common name, is its extensive teeth structure. Its dentition distinguishes the Atlantic wolffish from all the other members of the family Anarhichadidae. Both the lower and upper jaws are armed with four to six fang-like, strong, conical teeth. Behind the conical teeth in the upper jaw, there are three rows of crushing teeth. The central row has four pairs of molars and the outer rows house blunted conical teeth. The lower jaw has two rows of molars behind the primary conical teeth. The wolffish’s throat is also scattered with serrated teeth.Atlantic wolffish inhabit both the west and east coasts of the Atlantic. In the west Atlantic, they are seen as far north as the Davis Strait, of the Canadian territory of Nunavut, populating the shores of GreenlandNewfoundland, and Nova Scotia, extending as far south as Cape Cod. Although they are seldom seen south of Cape Cod, there have been sightings in New Jersey. The most dense populations are in Georges Bank, the Gulf of Maine and the Great South Channel.[4] In the eastern Atlantic, they range from Russia’s White Sea and Novaya Zemlya, through the Nordic countries and British Isles, to the Bay of Biscay. Atlantic wolffish are primarily stationary fish, rarely moving from their rocky homes. They are benthic dwellers, living on the hard ocean floor, frequently seen in nooks and small caves. They like cold water, at depths of 20 to 500 m (66–1,640 ft).[5] They are usually found in water temperatures of −1 to 11 °C (30–52 °F). Since they can live in near-freezing waters (salt water only freezes at slightly below 0 °C or 32 °F), to keep their blood moving smoothly, they contain a natural antifreeze. Three related species (Atlantic, northern and spotted wolffish) occur in the north Atlantic.[5] The northern wolffish has loose gelatinous flesh, but the other species are esteemed as food, both fresh and preserved.[5] They are marketed in Britain as “Scotch halibut” and “Scarborough woof”, or, simply “woof” in other areas of the northeast coast, and are a popular ingredient in fish and chips.


The eagle rays are a group of cartilaginous fishes in the family Myliobatidae, consisting mostly of large species living in the open ocean rather than on the sea bottom.Eagle rays feed on mollusks and crustaceans, crushing their shells with their flattened teeth. Devil and manta rays filter plankton from the water. They are excellent swimmers and are able to breach the water up to several metres above the surface. Compared with other rays, they have long tails, and well-defined, rhomboidal bodies. They are ovoviviparous, giving birth to up to six young at a time. They range from 0.48 to 9.1 m (1.6 to 29.9 ft) in length.Nelson’s book Fishes of the World treats cownose rays, mantas, and devil rays as subfamilies in the Myliobatidae. However, most authors (including William Toby White) have preferred to leave the Rhinopteridae and Mobulidae outside of the Myliobatidae.[2] White (2014) retained three genera (AetobatusAetomylaeus, and Myliobatis) in the Myliobatidae, while a fourth (Pteromylaeus) was synoymized with Aetomylaeus.[2] A 2016 paper placed Aetobatus in its own family, the Aetobatidae.This obscure genus is distributed in the Eastern Atlantic OceanIndian Ocean, and Pacific Ocean. These rays were named because they lack a sting on the tail.The common eagle rayM. aquila, is distributed throughout the Eastern Atlantic, including the Mediterranean Sea and the North Sea. Another important species is the bat eagle rayM. californica, in the Pacific Ocean. These rays can grow extremely large, up to 1.8 m (6 ft) including the tail. The tail looks like a whip and may be as long as the body, and is armed with a sting. Eagle rays live close to the coast in depths of 1 to 30 m (3 to 98 ft) and in exceptional cases they are found as deep as 300 m (980 ft). The eagle ray is most commonly seen cruising along sandy beaches in very shallow waters, its two wings sometimes breaking the surface and giving the impression of two sharks traveling together.Eagle rays unlike stingrays tend to live in the open ocean rather than on the bottom of the sea. Compared with other rays, their tails are quite long and they are a well-defined rhomboidal shape featuring distinct wings.