I’m (fairly) sure this is a Black Guillemot in winter plumage. Yes I know – it’s not black. Well they’re not, except in (summer) breeding plumage. And yes, it is difficult to see the bird in this shot. Here’s a better look. Personally, I prefer this very characteristic action shot.
Sony DSC-HX20V ƒ5.6 65mm 1/25 ISO 1000