Steelhead or Rainbow Trout
(A writing to Dewey Gillespie from a very respected friend AJH)
 

Most fishermen think of the steelhead as an errant rainbow trout which left fresh water to go to sea in some evolutionary coincidence, but the biologist feel that these trout, the closest relatives of the Atlantic salmon, were historically anadromous and that some became landlocked to produce non-migratory rainbows.
The rainbow and the steelhead are the same fish, although the sea instinct is handed down in some, while others, sometimes in the same waters, are stay-at-homes. Rainbow trout of the Great Lakes migrate up rivers and tributary creeks and are locally called steelhead. The largest rainbows reach maturity in deep lakes or at sea. The steelhead, coming fresh from the sea in silver and then regaining his vivid red stripe in fresh water, while retaining the metallic head that gave the sea run fish its name. The fighting qualities of the steelhead are very good. In my opinion, nothing excels the Lordly Atlantic Salmon on a fly rod.