The Fish

(Non-Native Fish) Two dorsal fins including one adipose fin, broad square tongue with 11-12 large teeth, light pectoral fins, squire tail, 9-10 rays in the anal fin.

Brown trout is something of a misnomer for many Great Lakes members of this species, since lake-run browns are predominately silver in color. In addition, the body spots, so characteristic of their stream-dwelling cousins, are often obscured in lake-dwellers.

Brown trout are close relative of the Atlantic salmon, and also were brought to North American waters as exotics. These natives of Europe and western Asia were introduced into New York and Michigan waters in 1883. Brown trout have thrived in their new home, and have become firmly established in all of our upper Great Lakes waters.

Lake dwelling brown trout are a wary lot. They hide in shallow water weed beds and rocky, boulder-strewn areas, and prefer a water temperature of 65-75°F. Since brown trout spawn in tributary streams in September and October, they begin to take up residence near stream outlets in spring and early summer.

After ascending a particular stream, brown trout spawners choose shallow, gravelly or rocky areas. The female creates a shallow depression (redd) in the gravel, in which the spawning fish deposit the eggs and sperm. When the process is completed, the female covers the redd with gravel.

The average lake run adult weighs 8 pounds, although individuals can grow to be much larger. Young browns are preyed upon by larger fish and by predatory birds such as mergansers. The diet of adult brown trout includes insects and their larvae, crustaceans, mollusks, amphibians, small rodents and other fish. They enjoy a rather long life-span, it appears, since researchers have observed them at up to 13 years of age.

(Native Fish) Brook trout have a long, streamlined body with a large mouth that extends past the eye. Color variations include olive, blue-gray, or black above with a silvery white belly and wormlike markings (vermiculations) along the back. They have red spots sometimes surrounded by bluish halos on their sides. The lower fins have a white front edge with black and the remainder being reddish orange. The tail fin is square or rarely slightly forked. During breeding time in the fall male brook trout can become very bright orange-red along the sides.

The brook trout is native to Michigan’s waters and is the state fish of Michigan. They can be found throughout most of the state in many creeks, streams, rivers, lakes, and in the Great Lakes. Brook trout require cool, clear, spring-fed streams and pools. They can be found under cover of rocks, logs, and undercut banks and have been described as stationary. Larger brook trout often inhabit deep pools moving to shallow water only to feed. They prefer temperatures from 57–60°F.

Spawning generally occurs in the months of October and November. Mature brook trout seek riffle areas with gravel in spring-fed streams, spring seepage areas of ponds, lake shores with swift currents, or lake bottoms where groundwater seepage occurs for spawning. Female brook trout use their tails to create a spawning bed (or redd) in gravelly areas. Redds may measure 1 – 2 feet in size. Female brook trout can produce between 100 – 400 eggs depending upon the size and age of the individual. After spawning the female covers the eggs with gravel. Brook trout eggs must get continuous amounts of oxygen in order for the eggs to survive. Depending upon water temperatures the eggs will incubate 2 to 3 months before hatching into sac fry.

The sac fry remain in the redd until their yolk sac is absorbed. Then, when they are about 1 ½ inches long, they venture away from the redd to feed. It takes about 2 to 3 years for them to mature and they usually do not live longer than 6 years. Brook trout living in streams often reach sizes between 7-9 inches. Great lake brook trout or coasters can attain larger sizes up to 25 inches and 10 pounds.

Brook trout have been described as voracious feeders with the potential to consume large numbers of zooplankton, crustaceans, worms, fish, terrestrial insects, and aquatic insects. Ephemeroptera, Trichoptera, and Diptera often make up a large component of their diet. However, they will often feed on whatever is most readily available.

Brook trout are avidly sought after by sport anglers, for food as well as for the sport. They can be caught by using various bait and lures including worms, crickets, grasshoppers, wet and dry flies, spoons, and spinners.

(Non-Native Fish) Two dorsal fins including one adipose fin, mouth and gums are light, small spots along rays on entire tail, 10-12 rays in anal fin

Steelhead is a name given to rainbow trout which live in the Great lakes. Rainbow trout are native to the Pacific Ocean along North America and to rivers and other fresh waters of North America west of the Rocky Mountains. They are a popular game fish, and for this reason have been introduced all over the United States.

Great lakes steelhead are usually found in waters less than 35 feet deep at temperatures of 58-62°F. They are often found near stream outlets, especially in spring and early summer. In the lake-dwelling part of their life cycle, they wander along the shoals eating plankton, minnows, surface and bottom insects and other aquatic life.

Although they feed primarily in mid-depths, they do take surface insects, including fly fishermen's flies. Larger rainbows will eat other small fish if available.

Great Lakes steelhead enter their spawning streams from late October to early May. At the present most spawning occurs in the spring, although more steelhead are beginning to spawn in fall. Spawning takes place in a bed of fine gravel, usually in a riffle above a pool.

Steelhead don't necessarily die after this; they may live to reproduce for as many as five successive years. Most rainbow trout return home to spawn in the stream in which they were born or planted.

Trout eggs hatch in four to seven weeks, depending on water temperature. Young trout may travel downstream to the lake in their first summer, or they may remain from one to three years in their home stream before migrating lakeward.

Individual growth varies greatly even within the same population. Most Great lakes steelhead reach sexual maturity at age three to five years, ahead of females. A mature 16-inch fish living in the Great lakes may continue to grow throughout its life and could reach 36 inches in length and up to 20 pounds in weight. However, average adult size for steelhead in 9 to 10 pounds while life expectancy in the Great Lakes is six to eight years.

Larger fish, fish-eating birds and mammals and sea lamprey are the steelhead's natural enemies. In turn, the steelhead finds itself competing with other salmon and trout, other predatory fishes and a variety of bottom feeders, for its food. It also competes with salmon and trout for spawning grounds.

Steelhead are valiant fighters and their flesh is outstanding no matter how it is cooked. An unbeatable combination that makes them one of the most popular North American sport fish.