Adult Cachinnans?

[Oliver]

Hello,

this gull swam in a small lake in northern Germany together with adult Herring Gulls. I presume that it is a Caspian Gull but want to hear your opinion, because I just saw it swimming. Compared to the Herrings it had small blackish eyes, a completely white head (the Herrings were almost in winter plumage), a different head shape and a small gonys spot. Furthermore, I think the outermost primaries are still growing. What I wondered about was the slightly darker greytone of the mantle and coverts compared to Herrings.










Thanks for your help,
Oliver

[lou bertalan]

hi oliver,

it looks fine for a female type caspian gull. outer 3(?!) primaries are shed, a bit unusual to see 3 missing but i'm sure p8 is half its way. usually old p10 is still there in mid september but it varies of course.

lou