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Lake Superior fish identification tips

Fishing Wisconsin

Identifying fish can seem easy at times but many times can be a challenge. It is not any different for Lake Superior anglers who can be confused when trying to determine whether the fish they have caught is a lake trout, splake or a "coaster" brook trout.

Lake trout / Splake / "Coaster" brook trout comparison

A splake is a hybrid cross of a female lake trout and a male brook trout that are presently stocked in the Chequamegon Bay / Apostle Island area. Tail shape is one of the better indicators of which one you have caught. The thumbnails below link to larger photos. Click on these photos to learn more about how to identify these unique fish in Lake Superior.  

lake trout, splake and "coaster" brook trout coaster brook trout

Steelhead / Coho salmon / Chinook salmon comparison

Steelhead can be correctly identified by using the following link to two illustrations.

identification guide for steelhead

Whitefish / Herring / Hybrid (Mule Whitefish) comparison

Mule whitefish, a natural 'sterile' hybrid, are occasionally caught by anglers in the Chequamegon Bay / Apostle Islands area. Anglers can be confused when trying to determine whether the fish they have caught is a lake whitefish, mule whitefish or a lake herring (cisco). The shapes of the mouth and the nose are the best indicators of which one you have caught.

The picture below shows all three for comparison.

Lake Whitefish (top) have an under-slung mouth.
Mule Whitefish (middle) have a slightly under-slung mouth.
Lake Herring (bottom) have a terminal mouth that opens evenly at the nose of the fish.

Whitefish / Herring / Hybrid (Mule Whitefish) comparison
Comparison of a Whitefish / Herring / Hybrid (Mule Whitefish)
Wisconsin DNR Photo