Coho salmon
  • Illustration by Joseph R. Tomelleri ©

    Oncorhynchus kisutch - scientific name

    Identification:

    Coho salmon can be hard to identify. Learn more about identifying Atlantic salmon, Chinook salmon, coho salmon, rainbow (steelhead) trout and brown trout.

    Two dorsal fins including one adipose fin, dark blue to green back with silver sides, white belly, and wide caudal peduncle. Inside of mouth white and gums between teeth gray or white, but tongue may be black. Small dark spots on back, sides and typically on upper lobe of caudal fin. Thirteen or more rays in anal fin.  The average adult Great Lakes coho salmon weighs five pounds.

    Fishing:

    Coho can be caught in Lake Michigan at any time, though the best fisheries on the lake's east side occur in early spring and again in late summer and early fall. The fish seem to travel the big lake counter clockwise; in the spring, the southern Lake Michigan ports of St. Joseph and New Buffalo boast excellent fisheries with anglers trolling near shore -- or high in the water column off shore -- often with crankbaits and floating/diving artificial minnows. There is often good fishing for anglers who use spawn bags or spoons off the piers as well.

    Fishing by both surf fishermen and trolling anglers occurs in Platte Bay as the fish stage for their spawning runs. Although they are caught in a number of rivers, there is a notable fishery in late October in the Manistee River and migrating fish are caught in the St. Joseph River as late as Christmas.

    The best fishing is in the Anna River watershed, which produces a good fishery for both open-water anglers in Munising Bay in spring and fall and through the ice in winter as well.

    Diet:

    In the Great Lakes, larger coho feed primarily on smelt and alewives; however they are opportunistic feeders and will feed on a number of species if they are available as forage. They compete primarily with steelhead for food.

    Life History:

    Coho’s typically migrate later than the other salmon and travel longer distances. Although natural reproduction has been documented, the fishery is largely sustained through stocking. The bulk of coho are planted in the Platte River, just downstream from the state's coho hatchery.

    Depending on the tributary, coho spawning runs occur from early September to November. Females excavate redds, or nests, in tributary stream gravel beds. Both male and female adults die soon after spawning. The next spring the eggs hatch and the young remain in the gravel for two to three weeks. They emerge in the late spring, as fry, and wait until their second spring before descending to the Great Lakes as smolts. Once in the lakes, they may stay near shore for a few months, and then seek deeper waters.

    Background Information:

    This is the fish that really started the Great Lakes salmon fishery. Like Chinook, coho are native to the Pacific coast of North America and parts of Asia. They were successfully introduced into the Great Lakes in 1966, when smolts where stocked in two Lake Michigan tributary streams; Platte River and Bear Creek (Big Manistee River tributary). There was excitement from anglers and fish managers when coho made their first spawning run in the fall of 1967. Since that time, the coho has become a popular sport fish, and many people come from all over the world to fish Michigan's great coho fishery.