Brown Trout, Salmo trutta
Identifying characteristics: (Non-Native Fish) Two dorsal fins including one adipose fin, broad square tongue with 11-12 large teeth, light pectoral fins, square 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 degrees 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.
Rainbow Trout, Oncorhynchus mykiss
Although not native to Michigan, rainbow trout have become one of the state’s favorite sport fish. From the inland lakes and streams to the Great Lakes, rainbows provide countless hours of angling enjoyment to all manner of fishermen.
Native to the Pacific watershed, rainbow trout came to Michigan when eggs were imported from California in 1876. First stocked in the Au Sable River, then four years later in the Lake Michigan watershed, rainbows can now be found in all corners of the state. Large specimens that inhabit the Great Lakes but travel inland to spawn in streams have come to be called steelhead.
Like any trout, stream rainbows can be caught by a variety of techniques; live bait, artificial lures and flies all produce. In large lakes, rainbows can be caught by trolling or by fishing with bait or jigging through the ice in winter. Though most commonly associated with clear-water lakes in northern Michigan, rainbow trout have been successfully stocked into a number of southern Michigan lakes as well, where they provide a unique fishery. Fishing after dark at the thermocline — the depth at which there is a major change in temperature — with live bait, salmon eggs or corn is the principle technique.
When many Great Lakes area anglers think about rainbows, however, they’re dreaming of steelhead, fish that are hatched (or stocked) in a river, migrate to out to the big water to mature, then return to their natal streams to reproduce. Although there is an open-water, off-shore fishery for steelhead in the summer in Lake Michigan, the bulk of anglers pursue them during their spawning runs, from the piers or in the streams. Steelhead begin filtering upstream in October and fishing for them continues through May, though between fish that have completed spawning (popularly called “drop-backs”) but have yet to migrate back out into the big lake and a few summer-run fish, there are almost always some steelhead in the streams.
Anglers can catch steelhead with a wide variety of techniques. They are often taken on spawn, either loose eggs tied in bags or whole skein cut into chunks, fished on the bottom or below a bobber. But other fishermen enjoy casting for them with spinners and plugs and still others, fishing from boats, simply drop crankbaits downstream and allow them to work in the current. Fly fishermen using nymphs or egg patterns fish along the bottom, though swinging large streamers in the current is catching on in popularity.
Michigan is one of the best steelhead fishing states in the country. Virtually all Great Lakes tributaries attract some steelhead with some of the best-known fisheries at the Manistee, Pere Marquette and St. Joseph Rivers in the Lake Michigan watershed, the Au Sable River off of Lake Huron and the Huron River in the Lake Erie watershed.
Brook Trout, Salvelinus fontinalis
Identifying characteristics: (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 degrees 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 continous 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.