Chinook Salmon

Oncorhynchus tshawytscha

Chinook salmon are also known as king, blackmouth, tyee and spring salmon.

Chinook salmon life stages - check out the dark spots all over the tail fin

Chinook salmon life stages - check out the dark spots all over the tail fin

Description: Chinook salmon are the largest of the Pacific salmon species; capable of reaching 120 pounds in weight and 58 inches in length early in the 20th Century but rare today; the average adult size is typically 10 to 40 pounds.  In the ocean, a Chinook has a silvery body ventrally, a bluish-green back covered with numerous black spots and black spots on both lobes of the caudal (tail) fin. The characteristic markings of these fish during spawning season include an olive greenish-brown to bronze coloration of the body and the same spotting as when in the ocean.  Chinook have teeth in black gums, (blackmouth), a feature together with spots on the entire tail fin distinguishes Chinook from coho which have teeth in white gums and spots only on dorsal lobe of tail fin.

In Whatcom County: There are two runs of Chinook salmon in the Nooksack River Basin; a spring run and a fall run. Spring run Chinook enter freshwater as early as March, but wait to spawn until mid-August through September. During this period, adults hold in deep, cool pools in the river; conserving their energy for spawning because all adult salmon stop feeding when in freshwater. Fall Chinook enter freshwater between September and late October to spawn soon after their arrival at the spawning site. In 1999, Puget Sound Chinook were listed as “threatened under the federal Endangered Species Act The spring Chinook salmon in the South Fork of the Nooksack River are particularly “threatened” and could become “endangered”.

Range: Sacramento- San Joaquin Basin northward to Alaska rivers of the southern Chukchi Sea; Siberian rivers of East Siberian Sea southward along coast to the Kamchatka Peninsula.  Chinook far more numerous in eastern Pacific than in Asia

Life History: Chinook salmon has two types of juvenile rearing behaviors; “ocean-type” and “stream-type”. Ocean-type fry leave for the estuary within a few months of emergence from gravel (typical of fall Chinook and many spring Chinook). Stream-type juveniles remain in freshwater for several months to a year before migrating to the ocean (typical of other spring Chinook). Once at sea, Chinook salmon usually spend 2 to 5 years feeding and growing before returning to freshwater to spawn. 

Spawning Season: Spring Chinook spawn from mid-August through September; fall Chinook spawn from September through October.

Habitat Requirements: Chinook are most often found in large streams or rivers, and many stocks spawn far inland (Chinook once spawned in Montana and Nevada). Spawning usually occurs in deep, fast water with cobble-size gravel. Spring Chinook require deep pools of cool water for up to a few months while maturing before spawning

Did You Know: Chinook is the least abundant of the Pacific salmon. It is the only salmon whose common name Chinook is capitalized because it is a proper noun from the indigenous Chinook Tribe of the Columbia River. The Sacramento River may have adult Chinook throughout the year with Winter, Spring, Summer and Fall stocks. Spring run Chinook are locally of great importance for the Lummi Nation’s First Salmon Ceremony in the spring. Chinook have been successfully introduced into the Great Lakes where they complete their life cycle entirely in freshwater. Also, successfully introduced in New Zealand’s South Island and southern Chile.