CLOSED: Herring Gull?

I saw some gulls in Juneau, Alaska. Are they Herring Gulls? And how do you tell the difference between adult Herring Gulls and Western Gulls. I think they really look alike.

Thanks,
Cui

Yep, American Herring Gulls.

Western is darker grey, and has a dark brown eye (yellow in AmHG); it is also a slightly bulkier bird with a thicker bill.

Resin

The darker grey back of Western Gulls is definitely one big difference (though it's hard to tell when photos are over exposed).

For the eye color, I think I saw some Western Gulls (I assume they are) with yellow eyes. Look at the left side one. Is that a Western Gull?

Thanks,
Cui

A better cut photo

Cui

In southern California? They have paler eyes there than further north in their range.

Resin

I saw it in Santa Cruz, quite in the northern part of California. That's really tricky!

Thanks,
Cui