The coho salmon has many different names. Some anglers call it a silver salmon or blueback and some call it a sea trout. Adult coho are steel-blue to slightly green on the back, brilliant silver on the sides, and white on the belly. These salmon are different than all others because the inside of their mouth is grey or black with white gums surrounding their teeth. They have a slightly forked tail with spots on the top half. Look for the 12-15 rays on the anal fin.
A Western Fish
Believe it or not, these salmon are not native to the Great Lakes. This fast growing predatory fish was brought here to help reduce the invasive alewife population and to offer trophy fishing to Great Lakes anglers. Coho are native to the Pacific Coast from southern California to northern Alaska. They are also found in Asia, south to Japan. Coho were first released in the Great Lakes beginning in 1873, but this effort failed. By 1966, the State of Michigan began stocking lots of coho and today these fish have spread to all of the Great Lakes. Coho can be found in Wisconsin waters along the shoreline of Lake Michigan from Kenosha north to Sturgeon Bay.
Wisconsin raises the coho salmon in fish hatcheries and stocks (releases) the young, called fingerlings, in streams that run into Lake Michigan. The eggs are collected from adult salmon in the autumn and are transfered to the hatcheries. The eggs are incubated for 60 days and hatch in January. After being raised for 13-15 months in a hatchery, the young fish are stocked in February, March and April along the Lake Michigan shoreline. Once in the lake, coho grow fast, eating mostly alewife and smelt. After less than two years in the lake, the fish are fully grown. From September through December adult coho migrate upstream to where they were released. Once there, they will attempt to spawn.
The coho is a very popular game fish in the Great Lakes region. Anglers like to eat this tasty fish and so does a parasite, the sea lamprey which feeds on blood and body fluids. Coho fingerlings are hunted by large carnivorous fish, birds, and mammals.
Fishing for coho starts in mid-April in southern Wisconsin near Kenosha and moves northward as the season goes on. The best way to catch coho is by trolling. Some top bait choices include plugs, spoons, and dodgers with flies. The best time to fish for coho is in the early morning and evening when they're active. Pier and shore fishing can be good, especially when casting with a spoon. Keep in mind that coho like water that is 54-57 degrees Fahrenheit. Remember: eating too much of certain kinds of fish can sometimes be harmful. Be sure to talk with an adult and follow all fish advisories issued by the Department of Natural Resources.
Cohos, chinooks, and steelhead have become popular sport fish. Fish biologists at the Wisconsin Department of Natural Resources, continue to stock them because they don't successfully reproduce on their own in rivers that feed into Lake Michigan. Waters in our state are not the clear, cold, well-oxygenated streams that chinook and their Pacific relatives, the coho and steelhead, need to spawn and reproduce. You can watch fish and egg collecting at several collection facilities along Lake Michigan tributaries. This job is done by trained fisheries biologists and technicians that work with the Department of Natural Resources.