Weasel

Dark blue dots show records since 2000
Mid blue dots show records from 1990 - 2000
Light blue dots show records from before 1990
-
Widespread.
We were emptying the moth trap one morning when there was a commotion from the blue tits in a nearby nest box. A weasel was nearby, and looking to get in. We tried chasing it off, but it didn't go far, and came straight back to the nest box when we went back to the moth trap. It stayed inside the box for a while, presumably making a meal of the single egg in there. Eventually it came out, but the blue tits continued to fuss around the box without going in for about ten minutes. Then they, too, left.
-
More information at http://www.abdn.ac.uk/mammal/weasel.shtml