Dog without a collar or owner does not have any right to exist in the woods of PA. We have enough problems with coyotes and a domestic dog gets much bigger than a coyote who (by itself) is limited to killing fawns and weak or injured deer. An 80 lb dog can kill a healthy deer especially in snow where a deer breaks through and the dog can run on top the hard crust easily running down deer. I had an experience with 2 dogs, One-German Shepherd Mix and other Rottweiler Mix; these 2 dogs ran down a doe and had her cornered in our front yard. When she tried to fend one dog off the other attcked tearing up her hind quarters. There was a foot of snow on the ground and she couldn't get away from them, she broke through, they ran on top the snow's hard crust. Both dogs are now Dead and I will kill every dog I see attacking deer. And do it with no apologies. I have a dog and I love dogs but dog without collar or owner risks getting shot if he runs in front of me.