Michael Beohm and I found a juvenile plumaged THAYER'S GULL at West Point Dam Friday morning, 11/12/04. The bird was above
the dam on the water beside the boom. It perched atop the boom at one point. The bird was present for about 30 minutes before
flying west out of sight (into Alabama). That was the only time we saw it there despite being there for several hours.
Thayer's Gull is not on the official GA list, though there have been reports in the surrounding states.
Bare in mind that Thayer's Gulls look something like Herring Gulls. Herring Gulls are at this location and can show
many variations, so keep that in mind if you look for the bird.
Size of a small Herring Gull. There were Herrings to compare it with.
Head round at all times and peaked in front.
Bill not large. Consistent with Thayer's range, but not stubby. The bill was black.
Color of the bird was a light brownish-gray with a touch of a frosty appearance.
Mantle was neatly checkered. Scapulars were dark centered.
Tertials were dark centered like shown in the Sibley book under "paler juvenile".
The tertials were not darker than the body.
The primaries on the sitting bird were darker than the body and appeared dark brown with light fringes.
The bird spread its wings a number of times and we could see:
what Sibley describes as the "dark outer webs of the primaries" (the effect of which were quite noticeable).
The underside of the primaries were light, unlike Herring Gull, with a very narrow dark trailing edge.
The secondaries were not dark like with Herring Gull.
The tail was a dark brown but not as dark as Herring Gull.
The darker primaries, webbing in primaries, dark centered tertials, and darker tail eliminated Iceland Gull from consideration.
Other birds at West Point:
Common Loons (30+)
Bald Eagles (4+)
handful of ducks
We then went down to Water F. George Reservoir:
LAUGHING GULL (10+)
SPOTTED SANDPIPER (2)
BALD EAGLE (about 8)
COMMON LOON (1)
handful of ducks and such