This widely ranging species exhibits extensive geographic variation. Birds here in Honshu are G. g. japonicus. Note the whitish eyes, black lores connected to a broad black moustachial stripe, large white wing-patch, and scaled crown. They differ strikingly from birds to the north in Hokkaido (G. g. brandtii) group characterized by tawny head, streaked crown, and reddish-brown eyes. They also lack the scaled crown and black lores of G. g. japonicus. Canon PowerShot SX60.
References:
Madge, S. & Burn, H. (1994) Crows and Jays: A Guide to the Crows, Jays and Magpies of the World. Houghton Mifflin, Boston.
Madge, S., Christie, D.A. & Kirwan, G.M. (2019). Eurasian Jay (Garrulus glandarius). In: del Hoyo, J., Elliott, A., Sargatal, J., Christie, D.A. & de Juana, E. (eds.). Handbook of the Birds of the World Alive. Lynx Edicions, Barcelona. (retrieved from https://www.hbw.com/node/60727 on 26 April 2019).