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Red Bluff Fish & Wildlife Office
Pacific Southwest Region

Hatchery Evaluation - Winter Chinook Salmon

A winter Chinook adult at Livingston Stone National Fish Hatchery prior to spawning

A winter Chinook adult at Livingston
Stone National Fish Hatchery prior to spawning
Photo Credit: Source FWS

Conservation & Monitoring

Sacramento winter Chinook salmon were first protected under the endangered species act in 1989. Livingston Stone NFH was completed in 1998 for the purpose of propagating winter Chinook to speed recovery of the population. The winter Chinook propagation program captures up to 120 returning adults each year and spawns them in the hatchery. Adult winter Chinook are captured primarily at the Keswick Dam fish trap, the terminus of upstream migration.

Winter Chinook hatchery-origin juveniles being released into the Sacramento River at dusk.

Winter Chinook hatchery-origin juveniles being
released into the Sacramento River at dusk.
Photo Credit: USFWS

The hatchery evaluation program applies the best available fish culture practices and genetic tools to ensure that the propagation program does not negatively affect the ability of the naturally-reproducing population to adapt to their environment. Research conducted by scientists of the hatchery evaluation program and other institutions have resulted in a several scientific publications that have advanced our knowledge of the species and that are also applicable to salmon worldwide.

The fish produced at Livingston Stone NFH are released into the Sacramento river to migrate to the ocean and mature, eventually returning to the river as adults to spawn in the wild. Winter Chinook enter the Red Bluff and Redding areas from December through March and spawn primarily from May through July. After spawning, Chinook salmon die, and biologists use information collected from their carcasses to learn about the population.

Winter Chinook Carcass

Winter Chinook Carcass
Photo Credit: USFWS

Sacramento River Carcass Survey

The winter Chinook carcass survey has been a cooperative effort between the U.S. Fish and Wildlife Service and the California Department of Fish and Game dating back to 1996. The survey is conducted in the mainstem Sacramento River in the primary spawning areas of winter Chinook, extending from the upstream limit of migration at Keswick Dam downstream to about confluence of Cottonwood Creek.

A biologist retrieves a winter Chinook salmon carcass from the Sacramento River.

A biologist retrieves a winter
Chinook salmon carcass from the Sacramento River Photo Credit: USFWS

Different reaches of river are surveyed daily, seven days per week, from May through August. Salmon carcasses are counted, and marked with metal tags. Subsequent resampling of the carcasses provides the basis of the information that is used to estimate the abundance of winter Chinook salmon using a “mark-and-recapture” type of estimate. Additonal information collected from salmon carcasses includes: gender, length, parental origin (i.e., natural- or hatchery-origin as determined by presence or absence of an adipose fin), and spawning location. Tissue samples are collected for genetic analyses.

Did You Know?

 

Last updated: August 22, 2014