Gull ID Please

To say that I'm gull ID challenged is a huge understatement. This was taken yesterday in Northern Utah as these gulls were feeding on dead carp. I'm curious about the larger, mostly white gull in the center. The bird has mud on its lower legs. Another view below.

Thanks for any help.

Ron

Here's a look at the wingspread.

My first thought was 'First Year Glaucous Gull" and I believe this is right after looking it up in the Peterson Field Guide. If you photographed this in Salt Lake City it would be a very good find - but certainly within the limits of its range.

What points me to this ID is its large size, coloration and marking on the bill

- Luke

Thank you Luke. Yes, this bird was photographed very near to SLC.

Its been 15 years since I got to see the "white-winged gulls" each winter in NJ, but I too think this is a First Winter Glaucous Gull. It looks very large compared to the other gulls.

New question for everyone: what other gulls are in these two images?

Looks like a Ring-billed Gull front left, a Ist year Herring Gull (perhaps) at the back left and a Herring Gull on the right in the orginal post?

Second image, ring-billed front left, Herring near the right side of the frame?

I'm with all of you on glaucous, ring-billed and herring. I was thinking of the possiblity of a California gull in the second image (gull on the right), but the mantle doesn't seem dark enough, althought the bill seems smaller than a typical herring.