My father, as a farmer, was plagued by Rabbits, when he bought his farm a couple of hundred acres of downland was unusable as grazing land, it belonged to the rabbits. Groups of farmers formed Rabbit Clearance Societies which employed a man to kill rabbits on a bounty system. One of his sayings was "Never employ the same man for more than two years" in this role. Why? because his job depended on there being rabbits and so he would (unconsciously) leave a few to breed. But if you get paid by the tail and you know the job isn't yours next year you clear them better. It is a classic case of the "Tragedy of the Commons", at least as far as the Bunnies were concerned. You too can now see this for yourself in the comfort of your own chair. Tragedy of the Bunnies.