California streams support the southern-most Chinook salmon runs on the west coast. Chinook salmon in California display a wide array of life history patterns that allow them to take advantage of the diverse and variable riverine and ocean environments. Chinook salmon are “anadromous” fish, migrating upstream as adults to spawn in freshwater streams, and migrating as juveniles downstream to the ocean to grow and mature. The time spent in the ocean and freshwater varies greatly among the various runs. At least seventeen distinct runs of Chinook salmon are recognized in California . These runs have been classified into six major groups, or Evolutionarily Significant Units:
•Southern Oregon and Northern California Coastal Chinook Salmon
•California Coastal Chinook Salmon
•Upper Klamath - Trinity River Chinook Salmon
•Central Valley Fall and Late Fall-run Chinook Salmon
•Central Valley Spring-run Chinook Salmon
•Sacramento River Winter-run Chinook Salmon
