How temperature affects juvenile coho salmon

Water temperature influences many aspects of a salmon’s life cycle, including egg development, juvenile appetite and growth, migration, and distribution. Coho salmon (Oncorhynchus kisutch), like most salmonids, need cool water for rearing, and they typically reside in a stream for a minimum of one year after hatching. Historically, coho were found throughout most of the 67-mile (108-kilometer) mainstem of Redwood Creek in Humboldt County, north coastal California. During at least the last decade, however, juvenile coho distribution in this area was limited to the last 12 miles (20 km) of the mainstem and a few large low-gradient tributaries.