Never heard of it, so I did a Google search and came up with this. Lake Winnebago Fishing Guide, Lake Poygan Fishing Guide, Bluegill, Bluegill Fishing, Walleye Guide, Walleye Fishing, Crappies, Pike, Fishing Report, Videos, Oshkosh, Winneconne, Ice Fishing, Perch
Links to a few other forums came up in the search asking about it and one reply was this was the only place they could find it.
One post also mentioned using the skin and belly meat of small fish cut into strips and soaked in a brine solution to achieve about the same results