Proper management of a game preserve, or any population of wild game that we have on public and private land here in the United States requires that you cull in order to maintain a healthy and vigorous habitat. The best way to do this is through controlled hunting. I’m assuming that in this case that control is exercised by the Duke of Westminster. Here, it’s done through hunting laws and regulations, licenses, seasons, etc. Such game management is essential to the survival of the species.
They should visit my buddy in Oklahoma, who breeds champion feral hog hunting dogs!