Report 26874: Possible footprints found near Mackinaw River

We are building a house near the Mackinaw River, so there is a lot of dirt pushed around. We have had lots of rain this year so that dirt turns to mud, I have been looking at the ground for arrow heads, and have seen several bare footprints ranging in size from a size 13 to three inches longer than my size 13's.  I have only been finding them since late September, and during cold spells as well.  Can't imagine anyone wandering around a construction site barefooted and in cold mud.