Large Gull on Baseline Res - ID unknown

[Jeff Parks]

Hey all -

I stopped by Baseline Reservoir this afternoon to see what was hiding out, and the first thing I saw was a large grey Gull in with several Ring-Billed Gulls.  I quickly snapped a few pictures before scrutinizing it through the binoculars before it took off.  It was significantly larger than the RBGU's, with a dark beak and pink legs.  Based on the color, I suspect it is a first- or second-year bird.  Once home, I tried to identify it using Sibley, and the closest I came was a Western Gull.  Does anyone have any ideas on this one?  I am still working on Gull ID's, and this one is not common around here. 

thanks for any input -

Jeff Parks
Boulder, CO

[Jeff Parks]

Well, I have had a few replies, and the most common suggestion is that it is a first-year Herring Gull.  It does look very much like one of the photos on allaboutbirds.org, so I have no reason to doubt that this is a pretty solid ID. 
I don't remember where I saw it, but I completely agree with the simplified Gull ID methodology that someone posted in a blog somewhere:  "There are only two kinds of gulls, white guls and grey gulls."  I guess this one is a grey gull ...

good birding -

Jeff Parks   
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