No interactions present.
GB-b Gull does have a pale "window" in the inner primaries, but it is not usually very distinct - and appears much as seen in this photo.
Other ID clues are the very heavy bill, relatively indistinct dark tail band, and coarsely marked upperparts.
Andy: Try and remember to add the scientific name when you post an ID (if you click on "get recommended" after entering the English name it will be done automatically in most cases). The scientific name is what Ispot uses to link to other observations of the same species.
GBBG also usually shows slight yellow at base of bill even in first winter birds.
GB-b Gulls frequently do have a paler base to the bill from their first winter, but this is not always the case. Some will have all black bills until at least their first summer - and in many others the paler base would not be vsible in a photo like this one.
Lat/Lng: 57.222082933351, -5.6745457649231
OS grid ref: NG782205