Most are left where they lay, If they are close to homes and such efforts will be made to move them. It doesnt take long for the buzzards to find them, the bones will be scattered about but to my knowledge dont present any problems. On another note it simply foolish to think that letting mass quanities of elmer fudds come on a your property and hunt hogs in a conventional matter will do anything to help. Hogs do resond to hunting pressure just like deer do. Feral hogs are mostly nocturnal to begin with and will go strictly nocturnal when pressured. That's where taking to the air is so effective as they can be made to move out of their day time bedding areas. You can kill more hogs in a day of flying than the average hunter will see in a lifetime.