Is this a California Gull or a Herring Gull? (1 Viewer)

Back in November I saw and photographed this bird at the Rio Jiboa in El Salvador. I identified it as a first-winter California Gull based on the pink basal two-thirds to the bill and on the dark greater coverts that are evident in the photos of both the sitting and flying bird. I have subsequently been told by someone with far more knowledge in this area than me that it is in fact a Herring Gull. I have very little experience with California Gulls or with the American subspecies of Herring Gull, so I am looking for someone who can confirm or refute this identification.
Thanks

Tom

I am not a gull expert, but just looked at these two birds in Sibley and from that would say yes to American Herring and nay to California gull. A couple of points that Sibley makes are
-California should have all dark primaries, herring has pale inner primaries (easily seen in the flight shot)
-California should have all dark greater coverts, but the dark feathers I see in flight are the secondaries, the coverts are all quite light.

HTH
Niels

hi tom,
i think this is indeed an american herring gull (smithsonianus). it has obvious pale wingpanels (inner primaries) which is wrong for california gull. structural it seems to be a heavier bird than a cal. gull. the pink based bill is normal in first winter smithsonianus as opposed to argentatus. it also is shorter and higher than the bill of california gull. the underwing is two-toned with lighter primaries whereas california gull would be rather plain brown on underwing.

The bird doesn't look like a California Gull. Too bulky and brown, and the tail is darker than the primaries (should be the reverse with a California).

However, if it is a pure smithsonius it has a few quirks as well. I see no trace of grey on the mantle, so it would be first winter. But... that bill is awfully pink for a first winter smith in November, it should be more like half and half with blending in the middle. Instead the bill is almost all pink in the second photo, with just a bit of black at the tip -- not typical at all for November, in my opinion.

What's up with the tail as well? OK, call the obvious patterning in the outer tail feathers, T5 & T6 as range of variation -- but it looks to me in the second photo like T3 and T4 have some lesser but still distinct patterning as well, maybe even a tad on T2.

Just seems a bit odd to me, though that goes with the territory with gulls...