Gull ID help, please, Eastern Ontario, Canada (1 Viewer)

[Tom Lusk]

I came across a large flock of gulls in a grain field this afternoon, and gulls have always been an ID nightmare for me.
Add in different stages of maturity and I'm beat before I start!
They were 150m from the road, so major crops.
All help appreciated

 

[nartreb]

The silver-winged ones are pretty easy: those are adult Herring gulls. (Possibly a Thayer's hiding among them, but those are less common. I can see the eye color on some and they look yellow => Herring.)
The black-winged one is... a black-backed gull. Pink legs => Great Black-Backed, not Lesser. (Lesser is also scarcer.)
That leaves the immature gulls. Strong salt-and-pepper wing pattern says first-winter black-backed. Odds would favor Great Black-backed but I'm not sure. Not sure we should trust the photo enough to say the bill is uniformly dark, but if it is, that's better for Lesser Black-backed. Somebody else may have an opinion based on the bird's size or bulkiness, I won't venture to try.

 

[Harrybongo]

Hi. Agree with, Herring and adult GBbG - for reasons already mentioned. The 1st winter gull, with the very marbled/mottled appearance and large robust bill, I'd say a GBbG? ...... but I'm in no way a gull expert!

 

[aeshna5]

Hi. Agree with, Herring and adult GBbG - for reasons already mentioned. The 1st winter gull, with the very marbled/mottled appearance and large robust bill, I'd say a GBbG? ...... but I'm in no way a gull expert!

Definitely Great Black-back.

 

[Tom Lusk]

Thanks so much, everyone. I had a couple figured out correctly, but missed some. More studying to do...