Rainbow trout are native to the rivers and lakes of the west coast and northern United States. They can also be found in the central and eastern areas of the country, southern Alaska and as far south as Mexico. Like all trout, rainbows seek out water with trees, and shoreline cover that provide shade and places for fish to hide. A natural predator, rainbows eat smaller fish almost from birth. Rainbow trout enjoy a varied diet of crayfish, crustaceans and sometimes plankton. They also feed on insects such as mayflies, caddis flies, and stoneflies. Rainbow trout can be identified by the colorful broad red or pink stripe that runs along its sides. Another thing to look for are prominent black spots that cover its entire body. Rainbow trout that are anadromous, spending part of their lives in the ocean, are called steelhead trout. Steelheads are silvery when they live in the ocean.