Carrion or Large-billed Crow, Japan (1 Viewer)

1 September 2019. Glover Garden, Nagasaki, Nagasaki Prefecture, Japan. This is the only photo I was able to get.

Hi!

I live in Hokkaido,
so the only 2 we basically have are:
the Large-billed and the Carrion, and rarely a Rook.
Given the shape of the forehead
(between a carrion or a Large-billed Crow),
it would have to be a Carrion, as it is more rounded.
The Large-billed Crow has a large forehead
and a tremendously larger beak.
So I personally in my humble opinion,
I would look more for a Carrion Crow or a Rook for where you saw it.
I have only been birding for a few years now, so that is me.
Wait a minute...
Are you the one who made the Gull flowchart
and are connected to CCSF?
thumbs up for that.

God Bless,

Jeff

Carrion by the head shape

Thanks. I also asked on the Kantori English Language Japan birding group. I got one reply saying Large-billed based on the bill but without anything more specific. Another commentator seemed skeptical saying about the bill "it seems to look curved but I wouldn’t be so sure watching from almost front."

I've been checking a lot of this duo over the last year orso (at inaturalist) and often they are impossible to tell apart. Slender looking Large-billeds can appear to be Carrion, and vice versa.
I would not dare label this one with 100% certainty.

cheers,
Gerben

I cant help with the photo and have limited experience only having seen many of both over two weeks at the end of February but I found in the field good views generally allowed ID but less than ideal views did not and there were always some that were far from obvious.