If you've visited Isle Royale as an angler, or even as a non-angler, you've probably heard of at least a few of the fish species present in the park. Lake trout, brook trout, and lake whitefish may all come to mind if you've fished the Lake Superior waters of the park. Northern pike, yellow perch, and perhaps walleye might be on your list of fish from inland lakes of the park. But did you know there are over 40 documented species of fish at Isle Royale. Some of these species are found only in Lake Superior waters and others are found only in the inland lakes or streams. A few species exist in both areas. Species diversity ranges from highly sought species such as lake trout and salmon to rainbow smelt and cisco or minnow species that may be mostly unknown, but are important contributors to the overall species assemblage.