The rainbow trout is distinguished by its white mouth, black spots and entire tail and its 12 or fewer anal fin rays.

The rainbow and the steelhead are the same species, differing only in spawning behavior. The rainbow spends its entire life in streams, whereas the steelhead is anadromous in that it migrates to a stream to spawn after living in the ocean or a large lake.

Rainbow trout feed on insects and fish. Many spawn in early spring with eggs laid in gravel at the head of a riffle area, but some are fall spawners. Rainbow trout as well as other trout do not normally die after spawning, like Pacific salmon (coho, chinook and pink).

Rainbow prefer water temperatures of 55-60 degrees F. They are known as great migrators or wanderers.

Some rainbow reach a hefty 16 pounds at age six, although the average rainbow caught averages five pounds. The largest caught to date in Illinois weighed 24 pounds and 13 ounces.

May, June, July and August are the best months for boat fishing for rainbow. Bank fishermen catch rainbows in the spring, casting small lures or using bait such as small alewives, nitecrawlers and spawn sacs. Winter fishing for rainbow is good in the power plant warm water discharges and they are occasionally taken while ice fishing in harbor.