Just like it was a necessity for a gamekeeper's livelihood to kill every hawk, eagle, falcon, kite or harrier that appeared over the land he was looking after?
There is almost always an alternative to killing. If, because of our way of life, we are unable to share the land with our fellow creatures, then it is surely encumbent on us to take steps to deter them. Done successfully this should have the added advantage of being a more permanent solution. Killing a batch of animals only allows others of the same or another species to extend their territories.