Chinook salmon are also known as king, spring, blackmouth, and tyee salmon.
Description: Chinook salmon are the largest of the Pacific salmon species; capable of reaching 120 pounds in weight and 58 inches in length (although the average adult size is typically 10 to 40 pounds). The characteristic markings of these fish during spawning season include an olive greenish-brown to bronze coloration of the body and black spots found above the lateral line and over the entire tail. They also have black gums, which earned them the name “blackmouth” from many old-time fishermen.
Range: San Joaquin River, California to Hokkaido, Japan; introduced to Chile, New Zealand, and the Great Lakes.
Abundance: Least abundant of the North American Pacific salmon.
Life History: Chinook salmon have two types of juvenile rearing behaviors; “ocean-type” and “stream-type”. Ocean-type Chinook salmon fry migrate from their natal (birth) streams to the saltwater environment within a year of emerging from the gravel. These young salmon then spend 2 to 4 years along the nearshore, relatively close to the coast. In contrast, stream-type Chinook salmon rear in freshwater streams for 1 or more years before heading out to the ocean. Once at sea, Chinook salmon usually spend 2 to 5 years feeding and growing before returning to the freshwater to spawn.
Habitat Requirements: Chinook are most often found in large streams or rivers, and many stocks spawn far inland (Chinook salmon used to spawn in Nevada!). Because river systems are often used for hydropower generation, spawning habitat has been lost on many rivers, including the Columbia and Sacramento. Spawning usually occurs in deep, fast water with cobble-size gravel.
In Our Local Watersheds: There are two runs of Chinook salmon in the Nooksack River basin; a spring run and a fall run. Returning spring Chinook salmon enter the freshwater as early as March and/or April, but wait to spawn until August and/or September. During this waiting period these adult fish hold in deep, cool pools in the river; conserving their energy for spawning. The fall Chinook salmon enter the stream systems between September and November and spawn soon after their arrival in the freshwater. Our spring runs of Chinook salmon are native populations, and we have two genetically distinct populations of these fish; one in the South Fork of the Nooksack River and one in the Middle Fork/North Fork of the Nooksack River. Our fall run of Chinook salmon is a hatchery-based population. Both spring Chinook salmon populations were listed as “Threatened” under the Endangered Species Act in 1999. The spring Chinook salmon in the South Fork of the Nooksack River are particularly imperiled and nearly extinct, with less than 100 adults returning to spawn annually during the last few years.
Did You Know? Some males in stream-type populations never migrate out to sea. Instead, they are able to mature and spawn in the freshwater without ever leaving their home stream. These fish are often referred to as “residuals”. While Chinook, coho, and sockeye salmon occasionally have residuals, chum and pink salmon never do.
For more information on Whatcom County's Chinook salmon click here.