The coho salmon (Oncorhynchus kisutch; Karuk: achvuun) is a species of anadromous fish in the salmon family and one of the five Pacific salmon species. Coho salmon are also known as silver salmon or "silvers". The scientific species name is based on the Russian common name kizhuch (кижуч).
During their ocean phase, coho salmon have silver sides and dark-blue backs. During their spawning phase, their jaws and teeth become hooked. After entering fresh water, they develop bright-red sides, bluish-green heads and backs, dark bellies and dark spots on their backs. Sexually maturing fish develop a light-pink or rose shading along the belly, and the males may show a slight arching of the back. Mature adults have a pronounced red skin color with darker backs and average 28 inches (71 cm) and 7 to 11 pounds (3.2 to 5.0 kg), occasionally reaching up to 36 pounds (16 kg). They also develop a large kype (hooked beak) during spawning. Mature females may be darker than males, with both showing a pronounced hook on the nose.
The eggs hatch in the late winter or early spring after six to seven weeks in the redd. Once hatched, they remain mostly immobile in the redd during the alevin life stage, which lasts for 6–7 weeks. Alevin no longer have the protective egg shell, or chorion, and rely on their yolk sacs for nourishment during growth. The alevin life stage is very sensitive to aquatic and sedimental contaminants. When the yolk sac is completely resorbed, the alevin leaves the redd. Young coho spend one to two years in their freshwater natal streams, often spending the first winter in off-channel sloughs, before transforming to the smolt stage. Smolts are generally 100–150 mm (3.9–5.9 in) and as their parr marks fade and the adult's characteristic silver scales start to dominate. Smolts migrate to the ocean from late March through July. Some fish leave fresh water in the spring, spend summer in brackish estuarine ponds, and then return to fresh water in the fall. Coho salmon live in salt water for one to three years before returning to spawn. Some precocious males, known as "jacks", return as two-year-old spawners. Spawning males develop kypes, which are strongly hooked snouts and large teeth.
The traditional range of the coho salmon runs along both sides of the North Pacific Ocean, from Hokkaidō, Japan and eastern Russia, around the Bering Sea to mainland Alaska, and south to Monterey Bay, California.Coho salmon have also been introduced in all the Great Lakes, as well as many landlocked reservoirs throughout the United States. A number of specimens, (more than 20), were caught in waters surrounding Denmark and Norway in 2017. Their source is currently unknown, but the salmon species is farmed at several locations in Europe, making it probable that the animal has slipped the net at such a farm.
The total North Pacific harvest of coho salmon in 2010 exceeded 6.3 million fish, of which 4.5 million were taken in the United States and 1.7 million in Russia. This corresponds to some 21,000 tonnes in all.Coho salmon are the backbone of the Alaskan troll fishery; however, the majority are caught by the net fishery (gillnet and seine). Coho salmon average 3.5% by fish and 5.9% by weight of the annual Alaska salmon harvest. The total North Pacific yields of the pink salmon, chum salmon and sockeye salmon are some 10–20 fold larger by weight.
In North America, coho salmon is a game fish in fresh and salt water from July to December, especially with light fishing tackle. It is one of the most popular sport fish in the Pacific Northwest of the United States and Canada. Its popularity is due in part to the reckless abandon which it frequently displays chasing bait and lure while in salt water, and the large number of coastal streams it ascends during its spawning runs. Its habit of schooling in relatively shallow water, and often near beaches, makes it accessible to anglers on the banks, as well as in boats.
It is also pursued by fly fisherman in salt water.
Ocean-caught coho is regarded as excellent table fare. It has a moderate to high amount of fat, which is considered to be essential when judging taste. Only spring chinook and sockeye salmon have higher levels of fat in their meat. Due to the lower fat content of coho, when smoking, it is best to use a cold-smoking rather than hot-smoking process.
Historically coho, along with other species, has been a staple in the diet of several indigenous peoples, who would also use it to trade with other tribes farther inland. The coho salmon is also a symbol of several tribes, representing life and sustenance.
In their freshwater stages, coho feed on plankton and aquatic invertebrates in the benthos and water column, such as Chironomids, midge larvae, and terrestrial insects that fall into the water.Upon entering the marine environment, they switch to a diet of plankton and fish, with fish making up most of their diets after a certain size. Adult coho feed on a vast variety of prey items that depend on the region they reside in during their second year at sea. Spawning habitats are small streams with stable gravel substrates.
Salmonid species on the west coast of the United States have experienced dramatic declines in abundance during the past several decades as a result of human-induced and natural factors.
The U.S. National Marine Fisheries Service (NMFS) has identified seven populations, called Evolutionary Significant Units (ESUs), of coho salmon in Washington, Oregon and California.Four of these ESUs are listed under the U.S. Endangered Species Act (ESA). These are the Lower Columbia River (threatened), Oregon Coast (threatened), Southern Oregon and Northern California Coasts (threatened), and Central California Coast (endangered). The long-term trend for the listed populations is still downward, though there was one recent good year with an increasing trend in 2001.
The Puget Sound/Strait of Georgia ESU in Washington is an NMFS "Species of Concern".Species of Concern are those species for which insufficient information prevents resolving the U.S. National Oceanic and Atmospheric Administration's concerns regarding status and threats and whether to list the species under the ESA.
On May 6, 1997, NMFS, on behalf of the Secretary of Commerce, listed as threatened the Southern Oregon/Northern California Coast coho salmon ESU. [ citation needed ]The coho salmon population in the Southern Oregon/Northern California region has declined from an estimated 150,000–400,000 naturally spawning fish in the 1940s to fewer than 10,000 naturally producing adults today. These reductions are due to natural and man-made changes, including short-term atmospheric trends (such as El Niño, which causes extremes in annual rainfall on the northern California coast), predation by the California sea lion and Pacific harbor seal, and commercial timber harvesting.
More than 680,000 coho salmon returned to Oregon in 2009, double that of 2007. The Oregon Department of Fish and Wildlife required volunteers to herd fish into hatchery pens. Some creeks were reported to have so many fish, "you could literally walk across on the backs of coho," claimed a Portland television station. Lower temperatures in 2008 North Pacific waters brought in fatter plankton, which, along with greater outflows of Columbia River water, fed the resurgent populations. The 2009 run was so large, food banks were able to freeze 40 tonnes (39 long tons; 44 short tons) for later use.
Salmon is the common name for several species of ray-finned fish in the family Salmonidae. Other fish in the same family include trout, char, grayling, and whitefish. Salmon are native to tributaries of the North Atlantic and Pacific Ocean. 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.
The salmon run is the time when salmon, which have migrated from the ocean, swim to the upper reaches of rivers where they spawn on gravel beds. After spawning, all Pacific salmon and most Atlantic salmon die, and the salmon life cycle starts over again. The annual run can be a major event for grizzly bears, bald eagles and sport fishermen. Most salmon species migrate during the fall.
The eulachon, also called the candlefish, is a small anadromous ocean fish, a smelt found along the Pacific coast of North America from northern California to Alaska.
The chum salmon is a species of anadromous fish in the salmon family. It is a Pacific salmon, and may also be known as dog salmon or keta salmon, and is often marketed under the name silverbrite salmon. The name chum salmon comes from the Chinook Jargon term tzum, meaning "spotted" or "marked", while keta in the scientific name comes from the Evenki language of Eastern Siberia via Russian.
The Chinook salmon is the largest species of Pacific salmon as well as the largest in the genus Oncorhynchus. Its common name is derived from the Chinookan peoples. Other vernacular names for the species include king salmon, Quinnat salmon, spring salmon, chrome hog, Blackmouth, and Tyee salmon. The scientific species name is based on the Russian common name chavycha (чавыча).
The sockeye salmon, also called red salmon, kokanee 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 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.
Pink salmon or humpback salmon 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.
Oncorhynchus is a genus of fish in the family Salmonidae; it contains the Pacific salmon and Pacific trout. The name of the genus is derived from the Greek ὄγκος + ῥύγχος, in reference to the hooked jaws of males in the mating season.
The quillfish, Ptilichthys goodei, is a species of perciform fish, the only species in the genus Ptilichthys and family Ptilichthyidae. It is an elongated, eel-like fish that reaches 34 cm in length. It is native to the north Pacific Ocean, from the Bering Sea south to Oregon.
Lagunitas Creek is a 24 miles (39 km)-long northward-flowing stream in Marin County, California. It is critically important to the largest spawning runs of endangered coho salmon in the Central California Coast Coho salmon Evolutionary Significant Unit. The stream's headwaters begin on the northern slopes of Mt. Tamalpais in the Coast Range and terminate in southeast Tomales Bay, 1.5 miles (2.4 km) northwest of Point Reyes Station, California. Lagunitas Creek feeds several reservoirs on Mt. Tamalpais that supply a major portion of the county's drinking water.
Redwood Creek is a mostly perennial stream in Marin County, California. 4.7 miles (7.6 km) long, it drains a 7-square-mile (18 km2) watershed which includes the Muir Woods National Monument, and reaches the Pacific Ocean north of the Golden Gate at Muir Beach.
The coastal cutthroat trout, also known as the sea-run cutthroat trout, blue-back trout or harvest trout, is one of the several subspecies of cutthroat trout found in Western North America. The coastal cutthroat trout occurs in four distinct forms. A semi-anadromous or sea-run form is the most well known. Freshwater forms occur in both large and small rivers and streams and lake environments. The native range of the coastal cutthroat trout extends south from the southern coastline of the Kenai Peninsula in Alaska to the Eel River in Northern California. Coastal cutthroat trout are resident in tributary streams and rivers of the Pacific basin and are rarely found more than 100 miles (160 km) from the ocean.
The bocaccio is a northeast Pacific species in the Sebastidae (rockfish) family. Other names for this species include salmon grouper, grouper, tom cod (juveniles), and slimy. In Greek, sebastes means "magnificent", and paucispinis is Latin for "having few spines".
San Gregorio Creek is a river in San Mateo County, California. Its tributaries originate on the western ridges of the Santa Cruz Mountains whence it courses southwest through steep forested canyons. The San Gregorio Creek mainstem begins at the confluence of Alpine and La Honda Creeks, whence it flows 12 miles (19 km) through rolling grasslands and pasturelands until it meets the Pacific Ocean at San Gregorio State Beach. It traverses the small unincorporated communities of La Honda, San Gregorio, Redwood Terrace and Sky Londa.
The aquaculture of salmonids is the farming and harvesting of salmonids under controlled conditions for both commercial and recreational purposes. Salmonids, along with carp, and tilapia are the three most important fish species in aquaculture. The most commonly commercially farmed salmonid is the Atlantic salmon. In the U.S. Chinook salmon and rainbow trout are the most commonly farmed salmonids for recreational and subsistence fishing through the National Fish Hatchery System. In Europe, brown trout are the most commonly reared fish for recreational restocking. Commonly farmed nonsalmonid fish groups include tilapia, catfish, sea bass, and bream.
Boise Creek is a stream in Humboldt County, California, United States. From its origin on Orleans Mountain it flows 8.5 miles to join the Klamath River about 2.25 miles southeast of Orleans, California. The creek lies within the Six Rivers National Forest and is part of the Lower Klamath River Watershed.
Scott Creek, also called Scotts Creek, is a 12.2-mile-long (19.6 km) stream and surfspot in Santa Cruz County, California. It is a few miles north of Davenport and a few miles south of Waddell Creek.
Salmon population levels are of concern in the Atlantic and in some parts of the Pacific. Salmon are anadromous - they rear and grow in freshwater, migrate to the ocean to reach sexual maturity, and then return to freshwater to spawn. Determining how environmental stressors and climate change will affect these fisheries is challenging due to their lives split between fresh and saltwater. Environmental variables like warming temperatures and habitat loss are detrimental to salmon abundance and survival. Other human influenced effects on salmon like overfishing and gillnets, sea lice from farm raised salmon, and competition from hatchery released salmon have negative effects as well.
Juvenile fish go through various stages between birth and adulthood. They start as eggs which hatch into larvae. The larvae are not able to feed themselves, and carry a yolk-sac which provides their nutrition. Before the yolk-sac completely disappears, the tiny fish must become capable of feeding themselves. When they have developed to the point where they are capable of feeding themselves, the fish are called fry. When, in addition, they have developed scales and working fins, the transition to a juvenile fish is complete and it is called a fingerling. Fingerlings are typically about the size of fingers. The juvenile stage lasts until the fish is fully grown, sexually mature and interacting with other adult fish.
Cottus asper is a species of fish in the sculpin family known by the common name prickly sculpin. It is native to the river drainages of the Pacific Slope of North America from Seward, Alaska south to the Ventura River of Southern California. It extends east of the Continental Divide in the Peace River of British Columbia. It has also been introduced to several reservoirs in Southern California.
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