Subject: Glaucous Gull in Asotin Co., WA
Date: Jan 23 14:06:22 1998
From: Deb Beutler - dbeutler at wsunix.wsu.edu


I see that I have been "scooped"

On Fri, 23 Jan 1998 09:28:46 EST Richard Rowlett wrote:

>Probably everyone knows this already, but there is a GLAUCOUS GULL on the
>sand/mud bar with the Ring-billeds and Herring and one other (Glaucous-winged
>I think but maybe a hybrid of some sort) at Swallows Park, Clarkston, at 3pm
>Thursday, Jan 21.

I was at Swallow's Park on Wednesday, Jan. 21, around 3 pm, and saw the
GLAUCOUS GULL. I didn't see a gull that looked like a Glaucous-winged or a
hybrid Richard saw (but my gull identification skills are not very good; I'm
working on it).

LOCATION: Swallow's Park is located on the Snake River on the Washington
side, in Clarkston, Asotin Co., WA. To get there, from US 12, follow the
signs towards the town of Asotin (I can't remember the number of the
highway). Follow this highway under the bridge at Fleshman Way. Just after
the bridge, the is a big sign for Swallow's Park. There are at least three
driveways for this park; the gull mud flat is visible from the farthest
(upriver) parking area. The Idaho Birding Guide gives good directions to
the park in the Lewiston section.

The gull was on the mud bar with about thirty Herring and Ring-billed gulls.


The following is a transcript of my field notes on the Glaucous Gull. I am
posting so that gull experts can tell me if I am wrong or if I have missed
some thing. I am fairly new at this gull identification thing so any input
would be appreciated.


The bird was standing on the mud bar with the other gulls. It was obviously
lighter than the other gulls. I looked at it with a Bausch and Lomb
Discoverer zoom spotting scope set on 25x at a distance of 150 feet. It was
overcast but the light hadn't faded too much (after the gull left, the
clouds became thicK and the light faded. I studied the gull for about
fifteen minutes and checked the National Geographic field guide just briefly
to make sure it wasn't a Herring Gull. Then I made the following notes:

Size and Shape: The bird was identical to the nearby adult and third winter
Herring Gulls (HEGU) nearby except for light primaries. Same size and shape.

Eye color: Same as the HEGU; light whitish-yellow, no obvious iris ring.

Bill: Same size and shape as the HEGU. The bill was mostly yellow; about
3/4 the way down the bill, there was a black stripe on both the upper and
lower mandible; the stripe was about as wide as a Ring-billed Gull. The
very tip of the bill was yellow. Gape was yellow. There was no red on the
bill.

Head: Mostly white but with some splotches of light gray-brown. Not as
streaked as the HEGU.

Mantle: slightly lighter than the HEGU. Most of the feathers were light
gray but some were white marbled with buff-brown. The gull appears to be
molting from a juvenile plumage to an adult plumage.

Belly: All white

Primaries: very light colored. At a distance they appear pure white but in
the scope I could see they were marbling with buff-brown but it was very
light. Primaries extended beyond the tail.

Tail: appears to be all white or has slight marbling.

As I was writing my field notes, the bird flew away with a few HEGUs. In
flight, the gull appeared completely light on the top and underside of the
wing. The color of the mantle seemed to blend into wings and they appeared
to be the same color. They were clearly not black or spotted in any way.

I concluded it was either: Glaucous, Glaucous-winged or partial albino
Herring Gull.

Then I went home and spent an hour with my three main field guides: National
Geographic, Peterson's Western Birds, and Audubon Master Guide Volume 2 and
concluded it was a Glaucous Gull(GLGU) in third basic (winter) plumage. I
eliminated GWGU because they tend to have darker eyes than HEGU or GLGU and
a different bill shape and color, particularly in third winter. The wing
pattern didn't match either. The bill matched the description of the third
winter GLGU in Master Guide. The wing pattern seemed to suggest GLGU except
for the primaries which I assumed could still be juvenile plumage. The
primaries weren't black as in HEGU or darker than the mantle as in GWGU. I
assumed that a partial albino HEGU would be white in areas other than just
the primaries and would have a bill more liKe a third winter HEGU (small
blacK smudge on the lower mandible with a small red dot). Therefore, I
decided it was a Glaucous Gull.

Apparently, Richard Rowlett has confirmed this identification so I feel a
bit more confident about it.


Cheers

Deb Beutler
Department of Zoology
P.O. Box 644236
Washington State Univerisity
Pullman, Whitman Co., WA
dbeutler at wsunix.wsu.edu