Rainbow trout, who’s sea-going cousin is the Steelhead Trout, is a common fresh water trout who is known for putting up a hard fight. The average length of a rainbow trout is 15-20 inches. The body of a rainbow trout is somewhat compressed with a rounded snout and a larglankuth. Stream residents and spawners are darker with more intense coloring and lake residents are lighter, brighter and more silvery. They range from steel-blue, blue-green, yellow-green to almost brown and most all have a number of small black spots.
Rainbow trout are most commonly found in fresh water mainly west of the Rocky Mountains. They have also been introduced into New Zealand, Australia, South America, Africa, Japan, southern Asia, Europe and Hawaii. The rainbow trout species spawn from March to August in smaller streams. The female digs and spawns in several nests depositing 800-1000 eggs in each redd (depression in bottom where eggs are laid). These eggs usually hatch 4-7 weeks later. The life expectancy can be as low as 3-4 years but they generally live 6-8 years. They first feed on plankton then insects and as they grow older, crustaceans and other fish.
Certain environmental factors affect rainbow trout feeding methods. Bright sunlight with calm conditions will drive rainbow trout into deeper waters where the fish will then wait to feed or they may seek a preferred food available within the deeper waters. If a breeze picks up and the light levels drop, rainbow trout will move back to the shallows and resume feeding on what they had earlier left. Some smaller rainbow trout will take risks going into unfavorable conditions to get a preferred food but it is not common.