AL and Shoals Birders:
As I said in notes to ALBIRDS yesterday, an adult Iceland Gull was below
Wilson Dam yesterday morning. The bird was on the southernmost concrete
wall extending from the dam in a row of Herring and Ring-billed gulls
facing me as I was scoping from the south overlook. What attracted my
attention initially is a mark I've found helpful in detection of these
in a crowd -- white or nearly white underside to the tip of the folded
wing (compared to the black and white patterns shown by Herring and
Ring-billed). Once I was clued in to this feature, other identifying
characters could be seen, and occasionally it would stretch a wing to
show the under-primary pattern. After a short period it started feeding
below the dam, unfortunately staying at distance but still allowing some
photos of the wing pattern. Sue Moske refound it that afternoon, but I
haven't seen any reports from today.
Though many features are good for Thayer's, I believe this bird likely
has some intergradation with Kumlien's based on the wing pattern above
and below. Both are now ensconced under the moniker of Iceland, so it
doesn't matter for the species identification, but still is an
interesting challenge (in a gull nerd sort of way).
I've uploaded some distant photos with explanations of many of the
characters useful for identifying Thayer's in general, and discussing
the Kumlien's issue. We don't get the opportunity to study an adult
often in Alabama, so this was a fun experience. Photos begin at:
ICGU ad 020423 Wilson Dam Lauderdale Co AL GregDJackson - 4632b.jpg
photo - Greg D. Jackson photos at pbase.com
<https://pbase.com/gdjackson/image/173363427>
Greg
Greg D. Jackson
Birmingham, AL
g_d_jackson@xxxxxxxxxxxxx
