From my experience the majority of the time it is likely a neighbor that is trespassing or someone who the neighbor allowed to hunt. I would try an figure out whose property that he came off of and maybe show them the pics to see who it is. Many years ago we had a group trespassing on us. Talked to the neighbor and he said that he let a group on his place, but specifically told them to stay off of ours and explained exactly where the property line is. He never let that group hunt again.
Traditions only last if you pass them down to your kids!