Picking up on Sapper's tale - one problem with urban foxes is that they may be carrying various illnesses, and without any form of control (either by natural predator or by farmers) the risk is that diseases will be spread among the urban fox population, if not more widely.
My favourite urban fox moment (since put into a song)when I was living in central London was seeing one heading down my street one morning. It then apparently made its way into the lifts of the block of flats where I lived, and was seen later on an upper floor, so presumably had managed the lift controls in some way. (OK, OK, so probably it entered the lift when it was standing open and someone on an upper floor summoned the lift so that's how it happened, but I prefer my version). As that was the time when there were the big Countryside Alliance demos in London it made me think about the notion of an urban hunt, probably on motorbikes ....