Poaching doesn´t neccessarily mean shooting is involved. Many poachers use snares. They don´t make a noise and it´s required to catch someone putting the snare or taking the snared animal. Poachers who use snares definitely avoid running into someone when collecting their prey even if it means to abandon an animal. Poachers who use rifles would also avoid to get caught. So signalling the position would keep poachers away. After all police would put much more effort in catching someone who assaulted or killed a person than they would put in catching a poacher.
When I started hunting, hunters in neighbouring areas reported to my host that there was a new rifle in town even before I came in with the kill. So poachers using rifles would probably be detected real fast.