Midnitemo is bang on the nail about "feral", hunger turns you into a stone cold killer, it's in the eyes, you get that thousand yard stare, the look an Axe murderer has just before he chops you up
I got through the week on Three Rabbits, Five Wood pigeons and various small birds like Blackbirds and Sparrows. I collected Brambles, wild Apples and other fruit along an old abandoned railway line. This sounds like a lot of food but when you are walking all day to find it you are burning a lot of calories and you are always hungry. You slowly become obsessed with finding food, and that nice little birdie singing on the bush would look great with a stick up its arse over your fire. This was in Autumn with a good bounty of natural food and it was not comfortable by any means, having to do it in January would be a nightmare. In all reality this would have to be an absolute last resort, with threat of life to make me have to do this again. It can only be sustained for a short time, then you will have to seek shelter in more permanent buildings that have the resources near at hand. Our picture perfect countryside is a capable killer when you have to solely live off it.