West coast Gull

[William McBay]

While looking through some old video footage I came across a Gull that I took in Golden Gate Park, San Francisco. I remember that it caused some head scratching at the time. The footage was taken in May and the only other Gulls present were Western Gulls. This bird was smaller and appeared to have an injured leg. The plumage appeared bleached and the primaries were not black. Do you think it is a small "smithsonianus" or something else? Any comments would be welcome. I apologise for the quality of the videograbs.

[Colin Key]

Irrespective of plumage (which appears a bit "dirty", but could be due to photo artifacts), the bill on this brute looks like Larus marinus to me.

Colin (non gull expert :ohdear:)

[adriaens]

I have to say, I am a little bit puzzled as to why opinions like this are posted sometimes... I know it is the nature of the internet that anyone can post anything, but this does not really help.
Anyway, Colin, you are right that the bird has a heavy bill, and that this provides a clue to its identity.

[MichaelF]

My guess would be hybrid Glaucous-winged × Western. They both also have stout bills.

[Sherpa]

Colin, a quick word of advice and please take this in good spirit.

Great Black-backed Gull is extremely rare in the Pacific and there are no records for California as far as I know. That alone should set alarm bells ringing.

Adriaens was very polite but others might not be. If you feel compelled to write something about a subject you don't know a great deal about, please pause for a second, search around on the internet for clues and think twice about hitting the submit button.

[JanJ]

Colin publicly smacked, perhaps not such a good idea! However, he is not into gulls that´s for sure.
Not the most clear pic. but the contrast between dark secondaries and obviously pale innner primaries and obviously darker outers suggest som kind of hybrid. Heavy bill confirms in such case probably Western x Glaucous-winged.

JanJ

[William McBay]

I am aware of the problem hybrids between Glaucous-winged and Western Gull on the west coast, but this bird did not strike me as being as large as I would have expected, despite the fairly stout bill. The Western Gulls had huge deep bills, while I did not see any Glaucous-winged Gulls during my stay (work trip). I did see the Glaucous-winged Gull at Saltholme last year and it's bill was definitely more akin in size, if not shape. I do wonder if Thayer's Gull can be positively excluded.

[MichaelF]

I'd think safe to exclude Thayers - never seen one, but from pics I've seen it is structurally about the same as Iceland Gull, smallish, with a small, dainty bill, nothing like this hulking brute.

[Scott M]

Images of western x Glaucous-winged can be found at http://larus.hp.infoseek.co.jp/hybrid_2.htm and are of similar structure and plumage. Glaucous-winged hybrid of some type for me.