Hogs and boar are not afraid of much once they're fully grown. They have few natural predators, and animals known to prey pigs them typically only prey on pigl

Hogs and boar are not afraid of much once they're fully grown. They have few natural predators, and animals known to prey pigs them typically only prey on piglets, as a boar can turn the tables on even the deadliest predators if they get a little lucky (black bear and cougars for example). Your best bet for audio deterrence would be firing blank shells, and that's most effective on a sounder (herd) that's already been hunted.