Oncorhynchus mykiss are only native to the Pacific Coast of North America, extending from Alaska down to the border between California and Mexico. However, they have been introduced throughout the United States. and in every continent except for Antarctica for game fishing purposes. There are two forms: freshwater resident and anadromous. The resident form is commonly called rainbow trout while the anadromous form is called steelhead.
Biogeographic Regions: nearctic (Introduced , Native ); palearctic (Introduced ); oriental (Introduced ); ethiopian (Introduced ); neotropical (Introduced ); australian (Introduced )
Other Geographic Terms: cosmopolitan