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Chinook Salmon


Chinook salmon are easily the largest of any salmon, with adults often exceeding 40 pounds (18 kg). Individuals over 120 pounds (54 kg) have been reported.
 
Chinook salmon are very similar to coho salmon in appearance while at sea (blue-green back with silver flanks), except for their large size, small black spots on both lobes of the tail, and black pigment along the base of the teeth.
 
Adults migrate from a marine environment into the freshwater streams and rivers of their birth in order to mate (called anadromy). They spawn only once and then die (called semelparity).  They feed on terrestrial and aquatic insects, amphipods, and other crustaceans while young, and primarily on other fishes when older.  Juvenile Chinook may spend from 3 months to 2 years in freshwater before migrating to estuarine areas as smolts and then into the ocean to feed and mature. Chinook salmon remain at sea for 1 to 6 years (more commonly 2 to 4 years), with the exception of a small proportion of yearling males (called jack salmon) which mature in freshwater or return after 2 or 3 months in salt water.
 
There are different seasonal (i.e., spring, summer, fall, or winter) "runs" in the migration of Chinook salmon from the ocean to freshwater, even within a single river system.  In the U.S., Chinook salmon are found from the Bering Strait area off Alaska south to Southern California. Historically, they ranged as far south as the Ventura River, California.  Chinook salmon also occur along the coast of Siberia and south to Hokkaido Island, Japan. 
 
Habitat: 
Juvenile Chinook may spend from 3 months to 2 years in freshwater before migrating to estuarine areas as smolts and then into the ocean to feed and mature. They prefer streams that are deeper and larger than those used by other Pacific salmon species.
 
Critical habitat has been designated for the 9 ESA-listed Chinook salmon ESUs.
 
Distribution: 
In the U.S., Chinook salmon are found from the Bering Strait area off Alaska south to Southern California. Historically, they ranged as far south as the Ventura River, California. Maps of the 17 ESUs of Chinook salmon are available on the NMFS Northwest Regional Office website.
 
Chinook salmon also occur along the coast of Siberia and south to Hokkaido Island, Japan.
 
Population Trends: 
In recent years, some populations have shown encouraging increases in population size. Population trends for specific ESUs can be found in the 2005 status review report for Pacific salmon and steelhead.
 
Threats: 
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 various human-induced and natural factors.
 
There is no single factor solely responsible for this decline, given the complexity of the salmon species life history and the ecosystem in which they reside. For more information, please visit our Pacific salmonids threats page.
 
Conservation Efforts: 
A variety of conservation efforts have been undertaken with some of the most common initiatives including captive-rearing in hatcheries, removal and modification of dams that obstruct salmon migration, restoration of degraded habitat, acquisition of key habitat, and improved water quality and instream flow.
 
The Pacific Coast Salmon Recovery Fund (PCSRF) was established by Congress in 2000 to support the restoration of salmon species. The fund is overseen by NMFS and carried out by state and tribal governments. The 2006 PCSRF report summarizes their work in detail.
 
For more information about Chinook Salmon click here.
 
 
 
Last Updated: Mar 06, 2013
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