Your best bet is SSS.When people stop by looking for the dog well you haven't seen anything.Oh and those shots they heard well that was target practice.
I would just go over to the owner and/or contractor and let them know,"Hello, I noticed a dog attacking my livestock going to this property. Just wanted to let you know if you are ever missing a dog just come on over to the property line,because I leave animals I shoot out for buzzards to eat."...