I assume crapping on your stand is damage since you could slip on the poo if it's wet and fall off the stand LOL, so no furbearer permit required if you own the land, however the trapping season isn't in yet. The landowner nuisance permit is free and can be done over the phone with them mailing a copy, and you can start after them after the phone call with the permit #. If you are not the landowner have them put your name on the permit. I had a farmer do that for me so I could keep trapping foxes after the season ended due to the chicken snatching issues. This would be the better option for right now since DNR officers might argue coon poop on a tree stand is not "damage" lol. Go with the health aspect, plus I am sure they are eating your corn all up. Keep in mind you can't keep/sell the pelts if taken out of season under this.