Tweets,

I was doing a bit of gull watching this afternoon at the Cedar River Park in Renton, enjoying excellent views of a 1st winter Glaucous, mucho Glaucous-wingeds, several Westerns, Herrings, Thayers, Californias, Ring-billeds, and Mew when I noticed a huge white-headed, black-primaried, chequered-coverted gull standing next to three Glaucous-wingeds and dwarfing them in breadth of chest and weight of bill. The legs were whitish-flesh and the bill strikingly two-toned, pale pinkish or flesh at the base with a black tip, much like a 1st winter glaucous. The eye appeared dark. The entire head and belly were clean white with some grayish smudging on the sides of the breast, some duskiness about the eye, with finely scaled or barred upper back and a distinctive pattern of clearly defined rows of whitish checks on a gray background across what I take to be the coverts and scapulars. The exposed primaries were solid dull black with very fine white margins on the tips of at least the outer 4-5. I couldn't see the tail well but it appeared to fall a bit short of the wing-tips.

Of course I'd left the house without camera, cell phone, or field guides so had to dash home first to check it against the guides and to try to get in touch with somebody who might be able to verify it. I first spotted it about 3:15 PM and it was after 4 when I got home, given the nasty traffic on I-405, so let's hope it's still there tomorrow.

Discussion: The very contrasty plumage in a 1st or 2nd winter bird doesn't fit other large gulls, except Yellow-footed (Baja), Lesser Black-backed , and Slaty-backed, but it was decidedly larger than either Lesser Black-backed or Slaty-backed. Yellow-footed has a 3-year development sequence, so should show more adultish mantle color by now. The closest fit in my guides is the 2nd winter Great Black-backed in Sibley's guide, but without the pale eye and with the upper back with less gray.

Gene Hunn.
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