Rainbow Trout are native to the cold water rivers and lakes along western North America and the Russian far east. Adult stream-dwelling Rainbow Trout are typically between 1-5lbs, while those living in lakes can grow as large as 20lbs. The sea-going form of Rainbow Trout is commonly known as steelhead and can grow to over 30lbs. Typically, Rainbow Trout spawn during spring months in freshwater. There are more than 13 native subspecies of Rainbow Trout found in North America where these fish have adapted to coastal and inland waterways.