Steelheads are an ocean-going form of rainbow trout. Steelheads are longer than rainbow trout, ranging from 20-36 inches long. After migrating to the ocean, their color changes to a silvery-grey and they lose the broad red band along their sides that they share with the rainbows. Both steelhead and rainbow trout are highly desired sport fish. Steelhead have declined due to a variety of human and natural causes: water pollution, dams, groundwater pumping and other results of urbanization.

What they eat: Mostly insects, but also any smaller fish from the time they are born. Generally speaking, as they grow, they eat more fish and fewer insects.

Where they live: Tributaries of the Pacific Ocean in Asia and North America.

Claim to fame: Like salmon, steelhead return to their original hatching ground to spawn, but rejuvenate afterwards to return to the ocean and repeat the cycle.

Source: Wikipedia