As promised, here are the first set of cat tracks: the illusive bobcat. At least, I think so: they seem to fit the shape and size for a bobcat, and bobcats are at least somewhat common in the UP. We found these tracks on the inland side of Porter's Island, out beyond the end of Hunter's Point at Copper Harbor. The tracks extended for quite a way along the shoreline, but we never found any signs that it had been hunting -- at least successfully.
Any of my friends who are more familiar with tracks than I am -- feel free to correct me about the identity! I'm certain that these are not wolf tracks -- too close to town, and wolves are pretty uncommon on the mainland. But if there's something else I haven't though of, let me know.