Oncorhynchus tshawytscha

Chinook or King Salmon (Oncorhynchus tshawytscha) are the largest salmon. They may reach around 150 cm in length and can occasionally exceed 23 kg; other salmon rarely exceed 14 kg. These fish have black spots on the back and on the dorsal, adipose and both lobes of the caudal (tail) fin. The gums are dark at the base of the teeth. At sea, these fish are blue, green, or gray above and silver below. Small males are often dull yellow while large males are often blotchy with dull red on the side. Breeding individuals are dark olive-brown to purple. (Page and Burr 1991)

The Chinook is the least abundant of the Pacific Salmon. It is anadromous (moving from the ocean to freshwater to breed), occurring in the Pacific Ocean and coastal streams. It is found in northeast Asia and, in North America, in Arctic and Pacific drainages from Point Hope, Alaska, to the Ventura River in California, occasionally straying south to San Diego, California. This species is widely stocked outside its range, notably in the Great Lakes. (Page and Burr 1991)

In comparison to other Pacific salmon: Sockeye and Chum Salmon (O. nerka and O. keta) have no large black spots; Coho Salmon (O. kisutch) have no black spots on the lower lobe of the caudal fin and have gums that are light at the base of the teeth; and Pink Salmon (O. gorbuscha) have large oval black spots on the back and caudal fin and do not exceed 76 cm in length. (Page and Burr 1991)

Chinook Salmon spawn once and die. For detailed information on the biology and status of this species, including conservation issues, see this resource from the NOAA Fisheries Office of Protected Resources.

Adults return to natal streams from the sea to spawn (Ref. 27547). Fry may migrate to the sea after only 3 months in fresh water, some may stay for as long as 3 years, but generally most stay a year in the stream before migrating (Ref. 27547). Some individuals remain close inshore throughout their lives, but some make extensive migrations (Ref. 27547, 44894). Also found in lakes (Ref. 1998). Possibly up to 375 m depth (Ref. 6793). Epipelagic (Ref. 58426). Food in streams is mainly terrestrial insects and small crustaceans; in the sea, major food items include fishes, crustaceans, and other invertebrates (Ref. 27547). Young are preyed upon by fishes and birds (such as mergansers and kingfishers); adults are prey of large mammals and large birds (Ref. 1998). Highly regarded game fish (Ref. 27547). Flesh is usually red, but some are white; the red meat commands a higher price (Ref. 27547). Marketed fresh, smoked, frozen, and canned. Eaten steamed, fried, broiled, boiled, microwaved, and baked (Ref. 9988). Viscera said to contain high vitamin A content and used successfully as food for hatchery fish (Ref. 28971, 28977). The Alaska Salmon fishery of this species has been certified by the Marine Stewardship Council (http://www.msc.org/) as well-managed and sustainable (http://www.msc.org/html/content_485.htm).

stocked in rivers draining in to the Gulf of Maine

stocked in rivers draining in to the Gulf of Maine

Chinook Salmon are found natively in the Pacific from Monterey Bay, California to the Chukchi Sea, Alaska in North America and from the Anadyr River, Siberia to Hokkaido, Japan in Asia. It has also been introduced to many places around the world including the Great Lakes and New Zealand.

Biogeographic Regions: nearctic (Introduced , Native ); palearctic (Native ); australian (Introduced ); pacific ocean (Native )

occurs (regularly, as a native taxon) in multiple nations

Canada

Origin: Native

Regularity: Regularly occurring

Currently: Present

Confidence: Confident

Type of Residency: Year-round

United States

Origin: Native

Regularity: Regularly occurring

Currently: Present

Confidence: Confident

Type of Residency: Year-round

Global Range: Native range includes the Pacific Ocean and tributary drainages, in North America presently from the Sacramento-San Joaquin system (sometimes farther south) north to Point Hope, Alaska, and in northeastern Asia, from northern Japan to the Anadyr River. The species has been widely stocked elsewhere.

In the Columbia River basin, the Hanford Reach supports the largest population of fall chinook salmon; annual production is an estimated 20-25 million subyearling salmon (P. Hoffarth, Washington Department of Fish and Wildlife, unpublished data).

Historic Range:
North America from Ventura R. in California to Point Hope, Alaska, and the Mackenzie R. area in Canada; Northeast Asia from Hokkaido, Japan, to the Anadyr R., Russia

North Pacific and Arctic; introduced elsewhere.

Arctic, Northwest to Northeast Pacific: drainages from Point Hope, Alaska to Ventura River, California, USA; occasionally strays south to San Diego in California, USA. Also in Honshu, Japan (Ref. 6793), Sea of Japan (Ref. 1998), Bering Sea (Ref. 2850) and Sea of Okhotsk (Ref. 1998). Found in Coppermine River in the Arctic. Several countries report adverse ecological impact after introduction.

The Chinook Salmon is the largest of all Pacific salmon species, often larger than 100 lbs and longer than 5 ft. It is characterized by a deep blue-green back, silvery sides and a white belly with black irregular spots on the back, dorsal fin and both lobes of the tail. It also has a small eye, black gum coloration, a thick caudal peduncle and 13-19 anal rays. For spawning, both males and females develop a reddish hue on the sides, although males may be deeper in color. Males can also be distinguished by a hooked nose and a ridged back. The Chinook fry look very different, with well developed parr marks (vertical bars) on their sides.

Range mass: 61.4 (high) kg.

Average mass: 13.6 kg.

Range length: 147.32 (high) cm.

Average length: 91.44 cm.

Other Physical Features: ectothermic ; heterothermic ; bilateral symmetry

Sexual Dimorphism: male more colorful; sexes shaped differently

Dorsal spines (total): 0; Dorsal soft rays (total): 10 - 14; Analspines: 0; Analsoft rays: 13 - 19; Vertebrae: 67 - 75

Length: 80 cm

Maximum size: 1470 mm TL

150 cm TL (male/unsexed; (Ref. 40637)); max. published weight: 61.4 kg (Ref. 27547); max. reported age: 9 years (Ref. 12193)

Differs from other Oncorhynchus by large size (to 45 kg), small black spots on both lobes of the caudal fin, black pigment along the base of the teeth, large number of pyloric caeca (>100), and variable flesh color (white to pink or red); fry and parr have large parr marks extending well below the lateral line (Healey 1991).

Distinguished by the small black spots on the back and on the upper and lower lobes of the caudal fin, and the black gums of the lower jaw (Ref. 27547). Body fusiform, streamlined, noticeably laterally compressed in large adults, somewhat deeper than other species (Ref. 6885). Gill rakers wide-spaced and rough; pelvic fins with axillary process (Ref. 27547). Fish in the sea are dark greenish to blue black on top of head and back, silvery to white on the lower sides and belly; numerous small, dark spots along back and upper sides and on both lobes of caudal; gum line of lower jaw black (Ref. 27547). In fresh water, with the approach of the breeding condition, the fish change to olive brown, red or purplish, the color change being more marked in males than in females (Ref. 27547).

nektonic

Migrate from natal rivers to the sea as fry where they may occupy depths of 200 m, return upriver to spawn.

nektonic

Migrate from natal rivers to the sea as fry where they may occupy depths of 200 m, return upriver to spawn.

The Chinook Salmon is anadromous– born in freshwater, migrating to the ocean, and returning as mature adults to their natal streams to spawn. Freshwater streams, estuaries, and the open ocean are all important habitats. The freshwater streams are relatively deep with course gravel. The water must be cool, under 14 C for maximum survival, and fast flowing. Estuaries provide a transition zone between the freshwater and saltwater and the more vegetation the better because there will be more feeding and hiding opportunities. At sea, Chinook Salmon can either stay close to shore or migrate thousands of miles to deep in the Pacific.

Habitat Regions: temperate ; saltwater or marine ; freshwater

Aquatic Biomes: pelagic ; lakes and ponds; rivers and streams; coastal

Other Habitat Features: estuarine

Habitat Type: Freshwater

Comments: Chinook salmon generally spend most (often 2-4 years but up to 6 years) of their lives in the ocean. For spawning, they migrate up to several hundred kilometers upstream to their natal stream, where eggs are deposited in gravel bottoms of large streams and rivers.

Populations may differ dramatically in the timing of adult migration and, to a lesser extent, timing of spawning. There are two basic behavioral forms, stream-type and ocean-type. Stream-type chinook are typical of northern populations (i.e., Alaska and northern B.C.) and headwater (high elevation) tributaries of southern populations. These spend one full year as juveniles rearing in fresh water before migrating to sea, perform extensive offshore oceanic migrations, and typically return to their natal river in spring or summer, several months prior to spawning; occasionally males mature without ever going to sea. The ocean-type is typical of populations on the North American coast south of 56 degrees north latitude; these migrate to sea during their first year of life (normally within 3 months of emerging from spawning gravel), spend most of their ocean life in coastal waters, then return to their natal river in fall, a few weeks before spawning.

Depth: 0 - 200m.
Recorded at 200 meters.

Habitat: benthopelagic.

benthopelagic; anadromous (Ref. 51243); freshwater; brackish; marine; depth range 0 - 375 m (Ref. 58426)

Depth range based on 186 specimens in 1 taxon.
Water temperature and chemistry ranges based on 47 samples.

Environmental ranges
  Depth range (m): 0.055 - 268
  Temperature range (°C): 1.708 - 14.897
  Nitrate (umol/L): 1.787 - 27.924
  Salinity (PPS): 32.706 - 35.017
  Oxygen (ml/l): 2.801 - 8.585
  Phosphate (umol/l): 0.304 - 2.300
  Silicate (umol/l): 2.592 - 43.395

Graphical representation

Depth range (m): 0.055 - 268

Temperature range (°C): 1.708 - 14.897

Nitrate (umol/L): 1.787 - 27.924

Salinity (PPS): 32.706 - 35.017

Oxygen (ml/l): 2.801 - 8.585

Phosphate (umol/l): 0.304 - 2.300

Silicate (umol/l): 2.592 - 43.395
 
Note: this information has not been validated. Check this *note*. Your feedback is most welcome.

This species has been introduced or released in Dutch waters.

This species has been introduced or released in Dutch waters.

Non-Migrant: No. All populations of this species make significant seasonal migrations.

Locally Migrant: Yes. At least some populations of this species make local extended movements (generally less than 200 km) at particular times of the year (e.g., to breeding or wintering grounds, to hibernation sites).

Locally Migrant: Yes. At least some populations of this species make annual migrations of over 200 km.

Anadromous; migrates up to several hundred km upstream to the stream in which they were spawned. Different races differ in the timing of adult migration and spawning. Oregon coastal chinook stocks vary in ocean migration; some stocks migrate north, some migrate south, and one stock has a mixed north and south migration (see Nehlsen et al. 1991). There are two basic behavioral forms, stream-type and ocean-type (see Salo 1991). Stream-type chinnok is typical of Asian populations and of northern populations and headwater tributaries of southern populations in North America; spends one or more years as fry or parr in fresh water before migrating to sea, performs extensive offshore oceanic migrations, returns to natal river in spring or summer, several months prior to spawning; occasionally males mature without ever going to sea. Ocean-type is typical of populations on the North American coast south of 56 degrees north latitude; migrates to sea during first year of life (normally within 3 months of emerging from spawning gravel), spends most of ocean life in coastal waters, return to natal river in fall, a few days or weeks before spawning.

Anadromous. Fish that ascend rivers to spawn, as salmon and hilsa do. Sub-division of diadromous. Migrations should be cyclical and predictable and cover more than 100 km.

While in freshwater, Chinook Salmon fry and smolts feed on plankton and then terrestrial and aquatic insects, amphipods and crustaceans. After migrating to the ocean, the maturing adults feed on large zooplakton, herring, pilchard, sandlance and other fishes, squid, and crustaceans. Once the adult salmon have re-entered freshwater, they do not feed. In the Great Lakes, Chinook Salmon were introduced to control the invasive alewife population (National Wildlife Federation, 2002; Delaney and ADFG, 1994; Government of Canada, 2002).

Animal Foods: fish; insects; mollusks; aquatic crustaceans; zooplankton

Primary Diet: carnivore (Piscivore , Insectivore , Eats non-insect arthropods, Molluscivore ); planktivore

Adults return to natal streams from the sea to spawn (Ref. 27547). Fry may migrate to the sea after only 3 months in fresh water, some may stay for as long as 3 years, but generally most stay a year in the stream before migrating (Ref. 27547). Some individuals remain close inshore throughout their lives, but some make extensive migrations (Ref. 27547, 44894). Also found in lakes (Ref. 1998). Possibly up to 375 m depth (Ref. 6793). Epipelagic (Ref. 58426). Food in streams is mainly terrestrial insects and small crustaceans; in the sea, major food items include fishes, crustaceans, crabs and other invertebrates (Ref. 9137, 27547). Young are preyed upon by fishes and birds (such as mergansers and kingfishers); adults are prey of large mammals and large birds (Ref. 1998).

Comments: In fresh water juveniles feed opportunistically on terrestrial and aquatic insects. In salt water they eat crustaceans as well as other bottom invertebrates. Adults eat mostly fishes.

Spawning Chinook Salmon are the keystone species in many streams because so many other species rely on them for food. In the ocean, they are often one of the top predators. Chinook Salmon are now the top predator in the Great Lakes where they were introduced to control other non-native fish species (University of Wisconsin Sea Grant Institute, 2002).

Ecosystem Impact: keystone species

For young Chinook Salmon, predation is very high. Many species eat the fry and smolts, including striped bass, American shad, sculpins and sea gulls. Reaching adulthood does not release them from predation, however, as they are still prey to many animals when they return to spawn. Most common are bears, orcas, sea lions, seals, otters, eagles, terns and cormorants. People have made predation worse by concentrating adult salmon at dams and weirs (Pacific States Marine Fisheries Commission, 1996; National Wildlife Federation, 2002; NOAA, 2001; University of California at Berkeley).

Known Predators:

• striped bass (Morone saxatilis)
• American shad (Alosa sapidissima)
• sculpins (Cottoidei)
• gulls (Laridae)
• bears (Ursinae)
• killer whales Orcinus orca 
• sea lions (Otariidae)
• seals (Phocidae)
• otters (Lutrinae)
• eagles (Accipitridae)
• terns (Laridae)
• cormorants (Phalacrocoracidae)

Oncorhynchus tshawytscha is prey of:
Cottoidei
Phalacrocoracidae
Accipitridae
Laridae
Otariidae
Phocidae
Lutrinae
Ursinae
Alosa sapidissima
Morone saxatilis
Orcinus orca

This list may not be complete but is based on published studies.

Oncorhynchus tshawytscha preys on:
non-insect arthropods
Actinopterygii
zooplankton
Mollusca
Crustacea
Insecta

This list may not be complete but is based on published studies.

Whirling Disease 3. Parasitic infestations (protozoa, worms, etc.)

Epitheliocystis. Bacterial diseases

Enteric Redmouth Disease. Bacterial diseases

Edwardsiellosis. Bacterial diseases

Aeromonosis. Bacterial diseases

Feeds on insects, crustaceans and fishes

Feeds on insects, crustaceans and fishes

External fertilization in Chinook Salmon requires precise communication in order to ensure proper timing of gamete release. During the courtship, which can last up to several hours, the male vibrates and crosses in front of the female, while the female is preparing for spawning by digging the redd. The female has been shown to selectively choose larger males, who vibrate more. A few seconds before depositing her eggs, the female will shake quickly next to the male, inducing sperm release (Berejikian, Tezak, and LaRae, 2001).

Other Communication Modes: vibrations

Perception Channels: tactile ; chemical

The female digs a nest (called a redd) in the gravel and then deposits her eggs and the male deposits sperm. After 90-150 days (depending on temperature) the eggs hatch, and the alevins (fry with yolksacs attached to the underside) stay in the gravel until the yolksac is used up. The fry then emerge from the gravel in the spring and feed and grow for a few months to two years, depending on the stream system. They then migrate downstream as smolts, following the natural current. The smolts undergo huge physiological changes in their transition from freshwater to salt water. They then spend the next 1-7 years growing and maturing at sea. Growth rates in the ocean are much faster, and perhaps as much as 99% of the somatic growth occurs as sea. Mature adults will then return to their natal streams to spawn. Once the adults have re-entered freshwater, they no longer feed, and they complete sexual maturation during the freshwater migration (Pacific States Marine Fisheries Commission, 1996; National Wildlife Federation, 2002; NOAA, 2001; Delaney and ADFG, 1994; University of California at Berkeley; Government of Canada, 2002; Ewing and Ewing, 2002; Satterfield and Finney, 2002).

Adults migrate up to 4,827 km upstream to spawn (Ref. 6850). Migration from the sea begins in December so that the the first fish are near river mouths by spring (Ref. 27547). Once a female selects a spot, she begins to dig a nest, driving away other females during the period of nest building. The female is attended by a larger, dominant male and several smaller males who drive away other males. While the female digs the nest, the male courts her by coming to rest beside her and quivering; by swimming about over her, touching her dorsal fin with his body and fins; and occasionally nudging her side gently with his snout (Ref. 28978). Upon completion of the nest, the female drops into it and is immediately joined by the dominant male. The fish open their mouths, vibrate, and eggs and sperm are released. At this point smaller males may dart into the nest and release sperm. The female then quickly moves to the upstrem edge of the nest and begins to dig. The eggs are covered and a new nest is made. The whole process is repeated until the female releases all her eggs, which may take several days. The male then leaves the female and may mate with another female. The female guards the nest for as long as she can. Spent adults usually die a few days after spawning. (Ref. 1998, 27547).Reproductive strategy: synchronous ovarian organization, determinate fecundity (Ref. 51846).

The average age of spawning adults is 4-6 years, however, they can spend up to 8 years in the ocean or return after less than one year. The average age is slightly younger in the south with 2/3/4 year-olds most common; 5/6/7 year-olds are most common in the north. Often, females are older than males at sexual maturity. There is high mortality early because of high natural predation, and those smolts that do not reach a certain size before their first winter at sea will not survive colder temperatures. Human modification of the environment has led to even higher mortality, mainly due to siltation and decreased water flow which have reduced the availability of oxygen to the eggs and fry (Pacific States Marine Fisheries Commission, 1996; Delaney and ADFG, 1994; Government of Canada, 2002).

Range lifespan
Status: wild: 8 (high) years.

Average lifespan
Status: wild: 3-4 years.

Average lifespan
Status: wild: 9.0 years.

Average lifespan
Status: wild: 2.5 years.

Average lifespan
Status: wild: 5.0 years.

Average lifespan
Status: wild: 7.0 years.

Maximum longevity: 9 years (wild) Observations: As in other species of salmon, these animals normally age and die shortly after spawning. It is not considered ageing but rather sudden death. Although normally semelparous, the chinook salmon has alternative iteroparous life histories. Male jacks and parr mature early and parr can survive reproduction and mate again (Unwin et al. 1999).

The Chinook Salmon have seasonal runs in which all adults return to their natal streams and spawn at approximately the same time of year. Sexual maturity can be anywhere from 2-7 years, so within any given run, size will vary considerably. Salmon are semalparous, and shortly after spawning they die.

After migrating back to the exact place of birth, with very little straying, the adults span in the course gravel of the river. The female first digs a redd in the gravel with an undulating motion of her tail, while the male stands guard. The female then deposits her eggs (3000-14000) in the nest, sometimes in 4-5 different packets within a single redd. The male then deposits his sperm, and both parents guard the redd until they die, sometime within the next 25 days. Spawning is timed so that the fry will emerge in the spring, the time where the stream has the highest productivity.

Many streams have more than one run, with each run going to a slightly different location in the stream. In each location, different environmental factors will affect the timing of the run, all timed so the fry emerge in the spring. For example, in a stream with spring and summer runs, often the spring run will go to higher elevation and with the colder temperature, the eggs will take longer to hatch (Pacific States Marine Fisheries Commission, 1996; National Wildlife Federation, 2002; Matthews and Waples, 1991; NOAA, 2001; Delaney and ADFG, 1994; Government of Canada, 2002).

Breeding season: Spawning season varies, but the most common runs are in the summer and fall with some streams having runs in the spring and winter as well.

Range number of offspring: 3000 to 14000.

Range gestation period: 90 to 150 days.

Range age at sexual or reproductive maturity (female): 1 to 8 years.

Average age at sexual or reproductive maturity (female): 0.75 years.

Range age at sexual or reproductive maturity (male): 1 to 8 years.

Average age at sexual or reproductive maturity (male): 0.75 years.

Key Reproductive Features: semelparous ; seasonal breeding ; gonochoric/gonochoristic/dioecious (sexes separate); sexual ; fertilization (External ); oviparous

There is no parental care in Chinook Salmon, as both parents die before the young emerge. However, the decomposing adult carcasses provide necessary nutrients to the eggs and fry.

Parental Investment: no parental involvement

Overall, chinook salmon generally spawn at 2-7 years of age (typically 3-5) in fall, depending on the population. A small proportion of males (called jacks) mature after only spending about 6 months or 18 months at sea, and still others mature without having migrated to sea at all. Eggs hatch in about 2-3 months and alevins complete development in another 1-2 months (depending on temperature, hence related to latitude and elevation). Juveniles stay in fresh water for a few days or 1 year (rarely more). Adults die soon after spawning. Several distinct spawning populations may occur in one stream; these may differ in duration of juvenile rearing, size and date of ocean entrance, timing of adult return and spawning, age composition of spawners, fecundity, and egg size (see Nehlsen et al. 1991).

The Chinook Salmon has 17 distinct Evolutionarily Significant Units, (ESU) in the US only, two of which are endangered and seven of which are threatened.

ENDANGERED:

Sacramento River Winter Run,

Upper Columbia River Spring Run

THREATENED:

Snake River Fall Run,

Snake River Spring/Summer Run,

Central Valley Spring Run,

California Coastal,

Puget Sound,

Lower Columbia,

Upper Willamette,

CANDIDATE:

Central Valley Fall Run

NOT WARRANTED:

S. Oregon/N. California Coastal,

Upper Klamath Trinity,

Oregon Coastal,

Washington Coastal,

Mid Columbia Spring Run,

Upper Columbia Summer/Fall Run,

Deschules Summer/Fall Run

Many agencies have been set up to protect this species, including the Pacific Fisheries Management Council, the North Pacific Fisheries Management Council, and the National Marine Fisheries Service. The federal Magnuson-Stevens Act was made to protect the Essential Fish Habitat, the waters and substrates necessary to fish for spawning, breeding, feeding and growing to maturity. The Sustainable Fisheries Act has amended the Magnuson-Stevens Act.

The main causes for the declining fish populations are overfishing, damming and diverting water, habitat destruction, and introducing hatchery populations. Overfishing has decreased population sizes enough that all other causes, along with natural predation, can have extreme effects, and population sizes decrease rapidly. Damming causes decline because it blocks adults from returning to their birthplace and because smolts often get sucked into the turbines of hydroelectric dams and are killed. Diverting water away from salmon streams causes water temperature to rise, reducing the oxygen carrying capacity of the water. Temperatures could also become fatally high in the summer. Reduced water levels could expose eggs in the winter, or flows could be too low to carry smolts out to sea. Habitat destruction, including logging, clearing rivers, pollution, and wetlands destruction, take away shade and necessary protection for juveniles. After logging has changed runoff patterns, streams may contain too much silt and become uninhabitable. Pollution can cause many physiological problems, including increased susceptibiity to pathogens. Introducing hatchery populations adds to the decline because the introduced populations interbreed with the native populations and can reduce resistence to disease (Pacific States Marine Fisheries Commission, 1996; National Wildlife Federation, 2002; NOAA, 2001; University of Wisconsin Sea Grant Institute, 2002; Arkoosh and Collier, 2002).

US Federal List: endangered

CITES: no special status

State of Michigan List: no special status

Canada

Rounded National Status Rank: N4 - Apparently Secure

United States

Rounded National Status Rank: N4 - Apparently Secure

Rounded Global Status Rank: G5 - Secure

Reasons: Still widespread and locally numerous in large range in the North Pacific Ocean and associated streams; many stocks have been extirpated and many others have declined; habitat has been degraded by logging and other activities, and dams have impeded movements; releases of hatchery stock probably have masked declines/extirpations of some native stocks; see separate files for various chinook salmon populations.

Current Listing Status Summary

Status: Endangered
Date Listed: 04/06/1990
Lead Region:   National Marine Fisheries Service (Region 11)   
Where Listed: Sacramento River winter-run ESU

Status: Endangered
Date Listed: 08/02/1999
Lead Region:   National Marine Fisheries Service (Region 11)   
Where Listed: Upper Columbia spring-run ESU

Status: Threatened
Date Listed: 08/02/1999
Lead Region:   National Marine Fisheries Service (Region 11)   
Where Listed: Lower Columbia River ESU

Status: Threatened
Date Listed: 04/22/1992
Lead Region:   National Marine Fisheries Service (Region 11)   
Where Listed: Snake River spring/summer-run ESU

Status: Threatened
Date Listed: 12/29/1999
Lead Region:   National Marine Fisheries Service (Region 11)   
Where Listed: CA coastal

Status: Threatened
Date Listed: 04/22/1992
Lead Region:   National Marine Fisheries Service (Region 11)   
Where Listed: Snake River fall-run ESU

Status: Threatened
Date Listed: 08/02/1999
Lead Region:   National Marine Fisheries Service (Region 11)   
Where Listed: Upper Willamette River ESU

Status: Threatened
Date Listed: 08/02/1999
Lead Region:   National Marine Fisheries Service (Region 11)   
Where Listed: Puget Sound ESU

Status: Threatened
Date Listed: 12/29/1999
Lead Region:   National Marine Fisheries Service (Region 11)   
Where Listed: Central Valley spring-run ESU

Population detail:

Population location: Central Valley spring-run ESU�U.S.A. (CA), including all naturally spawned populations of spring-run Chinook salmon in the Sacramento River and its tributaries in California, including the Feather River, as well as the Feather River Hatchery springrun Chinook program
Listing status: T

Population location: Lower Columbia River ESU�U.S.A. (OR, WA), including all naturally spawned populations of Chinook salmon from the Columbia River and its tributaries from its mouth at the Pacific Ocean upstream to a transitional point between Washington and Oregon east of the Hood River and the White Salmon River, and includes the Willamette River to Willamette Falls, Oregon, exclusive of spring-run Chinook salmon in the Clackamas River, as well as 17 artificial propagation programs: See 223.102
Listing status: T

Population location: Puget Sound ESU�U.S.A. (WA), including all naturally spawned populations of Chinook salmon from rivers and streams flowing into Puget Sound including the Straits of Juan De Fuca from the Elwha River, eastward, including rivers and streams flowing into Hood Canal, South Sound, North Sound and the Strait of Georgia in Washington, as well as 26 artificial propagation programs: See 223.102
Listing status: T

Population location: Sacramento River winter-run ESU�U.S.A. (CA), including all naturally spawned populations of winter-run Chinook salmon in the Sacramento River and its tributaries in California, as well as two artificial propagation programs: See 224.101(a)
Listing status: E

Population location: Snake River fall-run ESU�U.S.A. (ID, OR, WA), including all naturally spawned populations of fallrun Chinook salmon in the mainstem Snake River below Hells Canyon Dam, and in the Tucannon River, Grande Ronde River, Imnaha River, Salmon River, and Clearwater River, as well as four artificial propagation programs: See 223.102.
Listing status: T

Population location: Snake River spring/summer-run ESU�U.S.A. (ID, OR, WA), including all naturally spawned populations of spring/summer-run Chinook salmon in the mainstem Snake River and the Tucannon River, Grande Ronde River, Imnaha River, and Salmon River subbasins, as well as 15 artificial propagation programs: See 223.102.
Listing status: T

Population location: Upper Columbia spring-run ESU� U.S.A. (WA), including all naturally spawned populations of Chinook salmon in all river reaches accessible to Chinook salmon in Columbia River tributaries upstream of the Rock Island Dam and downstream of Chief Joseph Dam in Washington (excluding the Okanogan River), the Columbia River from a straight line connecting the west end of the Clatsop jetty (south jetty, Oregon side) and the west end of the Peacock jetty (north jetty, Washington side) upstream to Chief Joseph Dam in Washington, as well as six artificial propagation programs: See 224.101(a).
Listing status: E

Population location: Upper Willamette River ESU�U.S.A. (OR), including all naturally spawned populations of spring-run Chinook salmon in the Clackamas River and in the Willamette River, and its tributaries, above Willamette Falls, Oregon, as well as seven artificial propagation programs: See 223.102.
Listing status: T

Population location: U.S.A.(CA) from Redwood Creek south to Russian R., inclusive, all naturally spawned populations in mainstems and tributaries
Listing status: T

For most current information and documents related to the conservation status and management of Oncorhynchus tshawytscha, see its USFWS Species Profile

Global Short Term Trend: Decline of 10-30%

Comments: At least 50 stocks have been extirpated; see Nehlsen et al. (1991) for a review of the status of various at-risk/special concern populations from California, the Oregon coast, the Columbia River basin, and Puget Sound. Of 866 stocks in British Columbia and Yukon, Slaney et al. (1996) categorized 17 as extirpated, 47 as high risk, 6 as moderate risk, 7 as special concern, 330 as unthreatened, and 459 as unknown status. Regarding spring runs outside the Sacramento-San Joaquin population: the run in Salmon River drainage (North and South forks, and Wooley Creek, California) apparently was stable at 1000-1500 adults in the 1980s; the flood of 1964 reduced available habitat for population in the South Fork of the Trinity River, and the population there now is much smaller than previously; most individuals in the Klamath-Trinity drainage are derived from hatchery stock. Ratner et al. (1997) conducted a population viability analysis of spring chinook salmon in the South Umpqua River, Oregon (this is part of the Oregon Coast ESU) and found a 95% probability of persistence of 200 years with no further habitat destruction; with continued habitat destruction, the population was projected to be almost certainly extirpated within 100 years.

Degree of Threat: A : Very threatened throughout its range communities directly exploited or their composition and structure irreversibly threatened by man-made forces, including exotic species

Comments: Initial cause of decline was adverse effects of logging, mining, irrigation withdrawals, and overfishing, then construction of hydroelectric dams blocked migrations and resulted in high mortality of smolts in turbines (Nehlsen et al. 1991, Williams et al. 1992). Spawning runs continue to be threatened by construction of dams and degradation of natural environment. Extinctions or large declines of some local native populations in recent decades may have been masked by releases of non-native hatchery stock (Williams et al. 1992).

Juveniles incur high mortality as they migrate through today's river systems and out to sea. Sources of mortality include hydroelectric turbines, mechanical bypass facilities (including transportation by barge or truck), and predation by non-native fishes. Gas bubble trauma (GBT)associated with total dissolved gas supersaturation (TDGS) at spillways also causes mortality and detrimental sublethal effects, but passage of juveniles through spillways may be the least damaging of the routes for juvenile passage at dams (Backman et al. 2002). In the Columbia River basin, adults were rarely observed with GBT, despite high TDGS levels (Backman and Evans 2002).

Concurrent with the construction of fish hatcheries, bacterial kidney disease became prevalent and may now play a significant role in mortality.

A change in climate, beginning around 1977, led to poor ocean survival.

See also threats comments for individual populations (ESUs).

Not Evaluated

Management Requirements: See Nehlsen et al. (1991) for general management recommendations for anadromous salmonids.

Allendorf et al. (1997) proposed criteria for prioritizing Pacific salmon stocks for conservation; data limitations introduce subjectivity into the process, so expert judgment and peer review should be incorporated into the process.

See Thomas et al. (1993) for information on habitat management for this and other at-risk fish species in the Pacific Northwest. Utter et al. (1989) recommended a conservative policy for stock transfers, based on distinct genetic differences among populations in different areas. See recovery plan for Sacramento-San Joaquin Delta native fishes (USFWS 1995).

Limiting flow fluctuations at all discharges below Priest Rapids Dam (Columbia River) would further protect subyearling fall chinook salmon (Tiffan et al. 2002). This would enhance production of invertebrate prey and reduce the stranding salmon on dewatered substrate or in disconnected pools.

Yearlings migrating downstream experience higher survival when spill is used specifically to pass fishes through nonturbine routes past hydroelectric dams (Muir et al. 2001).

Needs: Meffe (1992) gave reasons why the hatchery approach to recovery ultimately will fail, and he emphasized that overharvest and habitat destruction need to be addressed in a major landscape-level effort. See Nehlsen et al. (1991) for general protection recommendations for anadromous salmonids. See recovery plan for Sacramento-San Joaquin Delta native fishes (USFWS 1995).

The Chinook Salmon is very important to commercial, recreational, and subsistence fishermen. It has always been central to the Native American lifestyle on the Pacific coast, and now much of the economy of the Pacific Northwest is based on it. Despite being relatively rare (compared to other Pacific Salmon species) it is the most commercially valuable. It is also now an important big game fish in the Great Lakes and is a big tourist draw in both the Pacific and Great Lakes regions

(Pacific States Marine Fisheries Commission, 1996; National Wildlife Federation, 2002; Delaney and ADFG, 1994; University of Wisconsin Sea Grant Institute, 2002).

Positive Impacts: food ; ecotourism ; controls pest population

Comments: Important both as a commercial and sport fish (Healey 1991). This species made up the majority of the Columbia River harvest in the late 1800s. The largest commercial catches have been along the coast of British Columbia, with sizable catches also south to California and north to Alaska. The fall run in the California portion of the Klamath River supports important ocean and river fisheries.

fisheries: highly commercial; aquaculture: commercial; gamefish: yes; aquarium: public aquariums; price category: very high; price reliability: reliable: based on ex-vessel price for this species