Observed on the river side in Helmsdale, North Eastern Scotland. Not really certain about this - all help appreciated.
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I'd go for Pied, as the back is rather dark and blotchy and the rump is black. Admittedly, the flanks are not that dusky.
My Flickr photos...
Lat/Lng: 58.119166666667, -3.6501666666667
OS grid ref: ND028156