Steelhead, also known as steelhead trout, is the anadromous form of the coastal rainbow trout or Columbia River redband trout. They are native to cold-water tributaries of the Pacific basin in Northeast Asia and North America. Steelhead are iteroparous, meaning they can spawn multiple times in their lifetime, although survival is only around 10-20% .

Steelhead are ocean-going predatory fish with a typical lifespan of four to six years. They predominantly feed on zooplankton when they are young and then transition to eating fish, some rodents, mollusks, and crustaceans. Steelhead are generally more streamlined in shape and silvery or brassy in color as adults, earning them their name. The main defining physical characteristic for which the Steelhead is distinguished and earns its namesake is a chrome underside and olive-grey back reminiscent of a steel beam.

Steelhead spawn in freshwater, and smolts migrate to the ocean to forage for several years before returning to their natal streams to spawn. Steelhead trout that migrate to the ocean typically grow larger than the ones that stay in freshwater. Steelhead are vulnerable to many stressors and threats, including blocked access to spawning grounds and habitat degradation caused by dams and culverts.

Steelhead are viewed as a prized fish, not only for their high-fat content and succulent orange meat but also for their connection to the native environment. They have long served as an indicator for water quality, biological diversity, and overall ecosystem health, and they reserve a particular degree of recognition and respect amongst human populations that have historically relied on the diversity of.