Market hunting happened everywhere, but I would imagine that Lake Superior wasn't a big business hub. There probably wasn't train loads of ducks shipped to chicago or Minneapolis, but they were sold to local markets. Redheads and Canvasbacks sold for 2-7 dollars a pair, where most other ducks were getting .50 cents a pair maybe a dollar. So areas where redheads and Cans frequented were much bigger players in the market hunting. Places like the Dakotas. Lake Christina, Heron lake, Lake Koshkongong, Lake St Clair, obviously the Chesapeake bay among many others had well a well documented history in market gunning. They all had swarms of canvasbacks as well. But there were many other places where these ducks weren't in swarms the have documented market gunning. Lake superior could be one of them, but you will probably be the one who has to do some research on it. Your best bet is to start with you local historical society and see what you can dig up, maybe head to some of the larger towns on the lake, like duluth or superior and check there historical organizations. Then let us know what you find.