I do not know where you live, so your exposure to the actual wilderness might be limited, but if you had any real exposure, you would know that without big pred

I do not know where you live, so your exposure to the actual wilderness might be limited, but if you had any real exposure, you would know that without big predators (like wolves in the northern part of the world) or hunting, the herbivores would bread to use all the available resources they can get. Yes, ecosystems (that is, set of different species including plants) self regulate themselves, but species try to maximize their numbers. If their numbers get too big, they starve and by some unlucky coincidences, they my become extinct due to resource exhaustion. I actually hope that humans would be better in this.