Wolves and Bears

Yeah, right...that's the Scottish double positive indicative of an emphatic negative.
We're on an island, there is a finite amount of land, and it isn't connected to any continental hinterland and the sea crossing to the continent is over twenty miles.
It's all used by people, even if it's by foot, for sheep, for deer or trees.
Even after the ice age there wasn't enough time before the seas rose and the lands seperated for the full Eurasian flora and fauna to reach the British Isles. Ireland's closer than Europe, but they got even less than we did.
Wolves, lynx and bears don't do well next to people and their farm animals, they really don't. To make it worse the populations would very quickly become inbred and the whole 'island fauna' situation would develop.
Mini elephants on the Med isles in the past, giant swans, pigmy rhinos and the like, all gone now though.
Island animals have a hard time when the human population is actively using the land.
Someone decided he could just fence off an entire highland estate and create his own wilderness park in the Cairngorms....in a country with a responsible right of access, and the land contained Munros that folks challenge themselves to complete. He kept coming back to planning, got every loudmouthed supposed 'expert' to write to the broadsheets...it's still didn't fly. Besides, after the debacle of the last lynx escapee, and the claim of the sheep it killed (you note the owners claim that it was, "Most unlikely", yet the sheep were killed with a bite to the neck)
http://www.walesonline.co.uk/news/wales-news/escaped-lynx-accused-killing-seven-13871560
I don't think the local farmers will be in favour.
M