The biggest threat is the so-called conservationists. Conservationists have shifted from "sustainable use" to animal rights. An animal that does not have a "use" is a parasite. An animal that has a "use" will always be welcome on private land, while an animal that has no "use" will most likely be unwelcome. This might not sit well with many people, but it is reality. If you want animals to survive, don't make them useless. Unless you want just a handful of animals in public reserves. And even then, you will have to be prepared to spend a lot of money on protecting them from poachers.