Subject: Re: Thayer's Gull Question
Date: Oct 28 20:47:34 1997
From: Eugene Hunn - hunnhome at accessone.com
Gene Hunn, Seattle, hunnhome at accessone.com
My id routine is roughly as follows, assuming, of course, an adult:
Pink legs? Yes. That rules out California, Ring-billed, Mew, etc., not to
mention Lesser Black-backed.
Mantle as pale or paler than all the hulking Glaucous-wings, Westerns, and
their hybrid spawn? Yes. Also rules out Slaty-backed, etc. Go on.
Wing with sharply contrasting black tips? Yes. Rules out Glaucous-wings and
Glaucous-winged X Western hybrids (the latter mostly have dark gray wing
tips, and not so sharply contrasting) again plus Iceland including Kumlien's
Iceland Gull, with wing tips of some shade of gray.
Eye not glaring pale yellow? Yes (that is, no, it's not glaring pale
yellow). Rules out Herring. The iris may vary from pale brown to rich yellow.
Head more round and bill less heavy than the other pink-footed gulls? Yes.
Rules out Herring, etc. again. Now you're beginning to feel confident about it.
Finally, check to see if the black on the wing tip is limited, that is, less
extensive and more interrupted by white "windows" than is normally the case
with Herring and Ring-billed Gulls (which have mantles as pale or slightly
paler than Thayer's) and that from the underside the primaries look pale
gray, not blackish (as in Herring Gulls). You can see this best in flight
but it is also noticeable when the bird is standing or sitting as you can
see the top of the wing and front and the underside of the tip of the wing
in back, which should appear pale.
If the legs are a deeper pink than the other pink-footed gulls nearby, fine,
but I wouldn't rely too heavily on that mark.
Not infrequently, however, I find a bird that otherwise fits Thayer's Gull
but that has a paler eye, more like a Herring Gull, or that has dark gray
rather than black on the wing tips, more like a Kumlien's Iceland Gull. In
such cases I shrug my shoulders. By the way, I saw one like the latter at
Green Lake last Sunday. It could have been a dark Kumlien's, but hey....
If the bird is a first year bird... [save that for another thread].
Gene Hunn.
At 08:07 AM 10/28/97 -0700, you wrote:
>Hi Tweeters,
>
>I have been over to the Sequim-Dungeness area three times in the last two
>weeks (wonder why?) and have tentatively ID'd a moderately large number of
>Thayer's Gulls mixed in with the other gulls (Usually Bonaparte's, Mew,
>Glaucous-winged, California, and 'Puget- Sound': Glaucous-winged X Western
>Gulls). For example, at the John Wayne Marina, a Thayer's in a flock of
>about 40 Gulls, and on the rock wall in the parking lot at the Three Crabs
>Restaurant, 3 Gulls, one of which was a Thayer's. Features I use to try
>to ID a winter adult Thayer's: Smaller than the typical Glaucous-winged X
>Western Gull, with a less imposing bill and 'softer' rounder look to the
>head, bubble-gum colored legs, more mottled on the head and neck, dark
>primaries but not extensive like Mew or California, red dot on bill,
>lighter eye color.
>
>Sometimes I will be looking at a group of 60 gulls and can convince myself
>that 6 of them are probably Thayer's. My question is: am I fooling
>myself? Are these just a normal variation of hybrids...the details about
>the 'webbing' on the wing tip usually pointed out in field guides escapes
>me... Even when I'm birding with much better amateur birders, their
>reaction when I point one of these gulls out is typically:' Yeah, I can go
>with that', as if the ID is tentative and 'statistical', rather that
>positive. But the experts don't seem to have any trouble with the
>ID...what are they doing?
>
>
>Rick Romea "We might as well be walking on the sun"
>Seattle, WA - Smashmouth
>
>rromea at stioptronics.com
>206-523-5831 (Home)
>206-827-0460 X 316 (Work)
>
>
>