Here's an example of what happens when man screws with nature.
The Island of Isle Au Haut in Maine is part of Acadia National Park. Hunting is forbidden, and the deer population have no natural enemies.
Consequently, they overgraze the land and none of them ever reach 150 pounds. They are visibly skinny and appear to be half starved. It is impossible for the people to have a garden, so no one benefits from their status as a park.
What's the point?