Oncorhynchus tshawytscha (Fishes)

Species Description

The largest of all salmon, Chinook—or King—Salmon routinely weigh more than 40 pounds and can reach upwards of 120. Not surprisingly, Chinook prefer to spawn in bigger streams and rivers than other species, making their redds (a salmon "nest") in larger gravel and tolerating swifter flows than their smaller relatives.

Chinook Salmon are anadromous, which means they live part of their lives in saltwater, but begin and end their lives in fresh water streams. Chinook fry (a juvenile that is still developing in a stream) will spend anywhere between three months to two years in fresh water. Likewise, they will remain at sea from one to six years before making the run back to their home rivers to spawn.

The Endangered Species Act permits the federal government to protect imperiled species, subspecies, and distinct population segments. The term “distinct population segment” is a term of art that allows the government to protect portions of an entire species before a particular threat or population decline becomes so severe that the entire species is placed in jeopardy. For Pacific salmonids, the National Marine Fisheries Service has attempted to standardize how salmon populations are considered for protection by defining Evolutionarily Significant Units (ESUs) for each species of salmon. There are two federally protected Evolutionarily Significant Units of Chinook Salmon in the GGNP: the Central Valley Spring-Run ESU and the Sacramento River Winter-Run ESU. both are transient in the Park, present only when they swim through the GGNP’s marine waters to and from the ocean and their natal spawning streams.

Click the image above for a larger range map of this Chinook DPS.

This Chinook Salmon ESU was once abundant in California, with spawning populations in the Upper Sacramento River and several of its tributaries. Scientists believe that there may have been up to 200,000 fish in this population alone.

However, Shasta Dam blocked access to all of the ESU’s historic spawning habitat. When the dam was completed, it was not expected that this ESU would survive.

Fortunately, cold-water releases from Shasta Dam created suitable spawning conditions for the ESU for roughly 100 km downstream from the dam. The Sacramento River Winter-run Chinook Salmon are now entirely dependent on this artificially created conditions for their survival.

For many years after the dam was constructed, these artificial conditions did not seem sufficient to maintain the ESU. The population declined from 100,000 in the 1960s to perhaps several hundred individuals in the 1990s. In addition, The Sacramento River Winter-Run Chinook Salmon ESU was protected as threatened in 1990; then protected as endangered in 1994. Its endangered status was reaffirmed in 2005.

There has been some hope for this population in recent years. Since the late 1990s, the population has seen a population increase, and has hovered steadily at just under 10,000 individuals. But if the average rate of growth in the population does not change, some biologists believe that this ESU is certain to become extinct.

Conservation Action Item

Support the ESA:
Ask public officials for a strong Endangered Species Act

Chinook Salmon need cool, clean waters to reproduce successfully. Water diversions, dams, and water pollution are all lethal to their continued existence.

Salmon require strong federal protections to survive. The Endangered Species Act is our nation’s best safety net for salmon on the brink of extinction. Call your congressional delegation and tell them you support a strong Endangered Species Act so future generations can enjoy Chinook Salmon running in California’s rivers and streams.

Big Year Competitors have reported 0 sightings and taken 0 actions to help this species recover so far this year.

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