2.4

CC Chinook salmon can be distinguished from other salmon species by heavy spotting on their tails and black coloration inside their lower jaw and at the base of their teeth. CC Chinook salmon are nearly identical in appearance to other Chinook salmon and are separated from other Chinook based on their geographic distribution and genetic differences. CC Chinook salmon in the Eel River average around 56 cm (22 in.) in length.

An abundance of CC Chinook salmon has likely decreased by more than 90% from historical numbers, though reliable estimates are lacking, especially for the Eel River watershed. The Eel River once supported a cannery with catches over 500,000 Chinook and Coho combined per year in the late 19th century. In ‘good’ years, historic runs were on the order of 600,000 fish combined in the ESU, perhaps dropping to 30,000-50,000 in ‘bad’ years. Present numbers total approximately 5,000-20,000 fish each year.

CC Chinook are all fall–run salmon; the spring- run life history has been lost throughout the ESU. CC Chinook typically return to their natal rivers after spending two or three years at sea between September and early November, often following large early winter storms. Spawning in the larger basins peaks between late October and December, and eggs hatch after 40-60 days. The majority of CC Chinook salmon juveniles emerge from the gravel in the late winter or spring and migrate downstream within a few months. Smolts use food-rich tidal or flooded habitats with overhanging cover or undercut banks to forage before migrating to sea.

CC Chinook salmon in the Eel River are more closely related to populations in northern watersheds than those on found along the Mendocino Coast. Chinook salmon of unknown origin occasionally migrate to coastal basins south of the Russian River (e.g., Lagunitas Creek, Marin County), and are under consideration to be in included in the CC Chinook salmon ESU in the future based on their reported genetic similarities.