I visited this starling roost a couple of weeks ago just across the Scottish border near the Solway Firth.  After about half an hour, a couple of small flocks started to congregate and wheel around in the air above us.  Over the next hour more and more birds joined the group until the sky was full on thousands of bunched together starlings.  This Buzzard was one of a few raptors attracted to the spectacle, although I think the Peregrine had more luck.