Steelhead trout are actually rainbow trout that have spent a part of its life in the sea.  The difference between a steelhead and a rainbow is slight; however, due to their exposure to different habitats they have minor differences in color and shape.  When hooked, steelhead put up an acrobatic fight much like rainbows.  Steelhead's are also just as stunning as they are combatant, boasting the same vibrant colors of reddish-pink on a background of steely silver.

Color: Silvery sheen when near salt water. In fresh water, reddish-pink and silver sides, black spots
Dark to light green top and white belly

Size: 5 to 12 pounds average, depending on population and habitat. Up to 30+ pounds

Method: Cast and retrieve, flies, drift boat, trolling, eggs, bobber tactics

Gear: Medium-action spinning and fly rods

Range: Southcentral, Southeast, Alaska Peninsula

Season: Peak May - October

Table fare: Pale, reddish meat similar to trout Tasty pan-fried or baked

Record: 42 pounds, 3 ounces, Bell Island 1970
 
Appearance

Steelhead are more streamline and trimmer than rainbows.  In the ocean, steelhead's have a solid silver sheen.  However, when in freshwater, they develop the same vibrant side colors of red and pink, which sets them apart from the ordinary.  Coloration along the back is usually darker and ranges from blue-green to olive.  The belly is white and the lower sides darken into silver.  Steelhead's are also speckled with small black spots that appear on the lateral line, upper fins and tail.  In some populations, adults also have spots on their lower sides.  The color and overall body shape of Steelhead's are determined mainly by age, sex, and habitat.  Steelhead's fresh from the ocean are typically more silver than rainbows.  During spawning season, body color tends to darken and the two different types of fish become harder to tell apart.  Juvenile Steelhead's (called smolts) also closely resemble rainbows, but just before migrating to the ocean they develop their silver sheen.  The color of silver is necessary for survival in the ocean.

Location

Steelhead's annually enter coastal streams along the Gulf of Alaska, Alaska Peninsula and eastern panhandle.  Steelhead have not been documented west of the Susitna River and north of the Chignik River system; however, this area does thrive with rainbow trout.  In the ocean, steelhead can be caught as far west as the Aleutians.

Diet

Fish growth is almost always regulated by the availability of food, size of the habitat and the temperature of the water.  The first food steelhead will actively consume includes plankton, crustaceans, vegetation and insects.  As they move into deeper and larger water, they will begin eating eggs and salmon carcasses.  Within two to three years they will begin eating other live fish.  Upon reaching the ocean, steelhead dine mostly on fish and squid.
Angling Methods

Due to the spawning migrations triggered at different times, steelhead fishing is productive during nearly all spring, summer and fall months.  Medium-action spinning and fly rods with cast and retrieve methods work well.  Steelhead will take several different types of tackle including baits, lures, wobbling spoons, weighted spinners, flies, streamers, muddlers, yarn and egg patterns.  Fluorescent colors can sometimes work the best and some populations will prefer certain colors over others.  As with other fish, their diet will determine the gear.  Drift boat fishing and bobber fishing also are popular methods.  Depending on the depth of the water, fishing near the bottom and in deep holes can be effective.  Also, try faster water behind structures such as log jams and rocks. 

Life History

Steelhead's live a spontaneous lifestyle; groups from the same populations spawn at different times and winter in various places.  Some adults will leave the ocean and enter their natal fresh water streams as early as July.  “Summer steelhead,” as they’re sometimes called, aren’t common in Alaska except for Southeast (its still worth checking out).  Instead, most steelhead will begin their spawning migrations through August and October and even into winter.  Still, other Steelhead's in Southeast will begin their spring migrations in-between mid-April and June.  It’s not uncommon to see ocean fresh, silver steelhead intermixed with brightly colored ones, which have waited all winter for the arrival of
the spring spawners.

Actual spawning occurs mid-April through June.  Actual spawning and the sites chosen are very similar to methods used by salmon.  A female digs a nest, called a redd, and deposits the eggs while they are fertilized by a male.  Next, the female covers the eggs with gravel and leaves. 
Steelhead's do not usually die after spawning; this is especially true for those over 28-inches.  After traveling hundreds of river miles, many spawned out steelhead are battered and skinny as they begin to make their way back downstream.  As a strong survivor, their stores of body fat and silvery sheen will have returned by the time they reach the ocean.  Most fish will spend a year at sea before joining the spawning migrations again.

Meanwhile, the eggs hatch during spring months.  The tiny steelhead, called alevins at this stage, will remain underneath the gravel and receive nutrition from their attached egg sacs.  When the sac is depleted, the small fish, now called fry, emerge from the gravel and enter the stream current.  As they grow, they spend the summer in the shelter of shallow areas near shore.  The small steelhead, now two to three inches in length, will spend their first winter in fresh water.  In most cases, steelhead will wait approximately three years before heading downstream to the ocean.  In this stage they are called smolt and they average about six inches in length.

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