Steelhead trout don't necessarily die after they've returned to their native streams to spawn, but with the exception of the Atlantic salmon, salmon almost always do. The steelhead is a rainbow trout and has black spots and a red band down its side. Salmon lack the red band and are silver or dark colored above, with much larger spots along the back, the dorsal fin and the tail.
Chinook salmon are also much larger than steelheads. The chinook can grow to over 3 feet long and can weigh 40 pounds. Steelheads are a bit shorter than chinook salmon. They usually only weigh about 9 or 10 pounds, though some have been known to weigh as much as 20 pounds. Still, steelheads prey on young salmon, possibly because they compete with salmon for food and good spawning sites.
The steelhead doesn't develop the kype, the hooked jaw that male salmon develop during the breeding season. Steelhead trout also don't make the famously arduous trip that salmon make to return to their natal waters to breed.
The color of the salmon's flesh ranges from pale pink to bright red. The flesh of the trout is white and flaky, while salmon flesh is oily and robust.