Backgardenplinker
Member Extraordinaire
Foxes, among others, have no natural predators, if you don't control their numbers they will wipe out countless other species. Badger numbers are getting there too, highest they have been in decades
Foxs have been here for thousands of years as a native species. Your right they don't have natural predators when adults I assume.
A natural food web needs top predators to control the lower species population numbers. The fox population will naturally boom and bust.
It would be based directly on the population of its prey. Some years prey like mice would thrive on a good fruiting year for example and on a drought it's vice versa. Large population then small. Fox numbers will follow suit.
Nature has this balanced out though and overall there is an ecosystem that maintains itself.
So when humans provide the fox's with a glut of easily available food all year round every year. Be it prey from livestock or food waste it's natural the fox population will rise and rise and need controlling. It's not their fault. It's ours. It does mean we have to do the population balancing now to maintain things.
That is for sure.