This was the title of a debate at the RGS last year.
Earthwatch says:
“Could we really hear a wild wolf’s howl in Britain again? If human activity is to blame for the wolf’s demise in the UK, along with the local extinction of bears, lynx and beavers, is it now time to redress the balance and bring these captivating creatures back? Have your say – join the debate.”
The debate continues, and the debate details here still include many potentially useful comments.