I had this very distinctive Jackdaw the other day in Filey, feeding with 'regular' Jackdaws in the horse field by the clifftop in the Country Park. Knowing that they're seemingly not (yet) doable in the field, and being aware of the intergrade and ID issues of Jackdaw subspecies, I'm putting it out there more out of a will for documenting than anything else.
On current understanding, however, you could argue it's very hard to rule out the (highly) migratory Russian race,
C. m. Soemmerringii; the supposedly classic features of this subspecies are its broad, long, white neck collar, contrasting sharply with a pale nape and ear-coverts and the blackish cap and underparts (e.g.
Svensson & Shirihai, van Duivendijk, etc). A larger, heavier bill is another feature and, while a bit subjective, is arguably shown by this bird, too.
I've seen several candidate Scandinavian Jackdaws here on the coast, but with so much known overlap in features, they're a bit of a cul-de-sac; but comparing this bird with examples in the books and online (see for example the Dutch Birding article
here) of Russian
Soemmerringii, I think I'd struggle to find a better candidate.
