According to my RSPB bird book, the overwintering population is thought to be around 3000, and increasing - no doubt a consequence of global warming. Even so, it must be a rarety in Nithsdale. I have seen them in winter in my garden, too, although not this year so far.
Stunning bird, there are a couple around here, the female is more active when there are chicks. Also have a goshawk that frequents the oak trees behind the house along with a few red kites & buzzards that love to soar.
The commonest bird of prey around these parts (North Yorkshire) is now the Red Kite - I often see them overhead from my garden. Amazing, when you think that only a few years ago they were unknown outside mid-Wales.