Here are a couple of facts for you. First, every living creature, including your good self, has three essential requirements for survival. The first is habitat, in other words a home, shelter, somewhere to live. The second is sustenance, food and drink, found by many creatures within their habitat. Finally, we have protection, a degree of safety from those who would do us harm; protection if not always for each individual, at least for the species.
The second fact is that every living creature is either a hunter or is hunted. A predator or prey species and sometimes both. For prey species to survive, they must greatly outnumber the creatures that hunt them. If, for example, skylark numbers fall, the badgers, stoats, weasels, foxes, hedgehogs, crows, magpies, birds of prey…