Visiting Pied Jackdaw

After a few days of Chaffinches I thought I owed you a change of species?
These Pied Jackdaws arrived last year.I was told by the RSPB that they are gaining White plumage because of a change of environment or diet????
Whatever the reason,they are still handsome creatures with that crested head and bright blue eye!

Nikon D800 + Sigma 150-500 f5-6.3 O/S APO @ 500mm in DX mode + 750mm
1/160 sec. f 8 ISO 720