Chestnut-sided Warbler at Mill Creek delta, and Mew Gulls

Observers: Chris McCreedy
Remote Name:
Date: 09/29/2004
Time: 05:55 PM -0400


A hatch-year female Chestnut-sided Warbler foraging in the Narrowleaf Willows on the west edge of the Mill Creek delta, maybe thirty meters from Mono Lake's shore. She lacked chestnut on her flanks, but had a yellow-green head and back (fading into a gray upper tail), double wingbars (with a little yellow in the wingbars), a white throat and belly, and gray cheeks. She didn't seem to be in a rush to go anywhere, calmly feeding and preening all morning. Gaines' latest is August 21. Also two Mew Gulls at the nearby Wilson Creek delta. I used to work in Union Square in San Francisco, and saw many Mew Gulls everyday, but I would still be thrilled if someone double-checked me - it's been awhile. Foraging with California Gulls, but not interacting with them. Around 70-75% the size of a CAGU, with very small bills. First winter I believe, with grey backs contrasting with brown coverts. Dark eye. No dark markings behind eye such as you would see on Sabine's or Bonaparte's Gulls, other small gulls infrequently at Mono Lake. I clearly saw the "brownish remiges" described in Sibley. I have never used remiges in a sentence before. Ring-billed gulls are a possible ID, but I have seen many Ring-billed, and these two really seemed smaller, particularly their bills. The bills did not really have the "clean-cut black tip" described on a Sibley Ring-billed Gull. The mottling on the head and belly was smudgy, like on a Mew Gull, not dark and clear, as drawn on the Sibley Ring-billed Gull. One problem I have was that the smudging wasn't exactly brown, it was more of a dirty pale gray, if they really ARE Mew Gulls, I think Sibley got a little crazy with the brown paint. Their flight feathers were also not as dark as the Sibley RBGU ff. They were calmly feeding and standing in the bay just east of where Wilson Creek hits the lake. I also saw 1500-2000 Northern Shovelers (truly awesome), 3 late Yellow Warblers, a MacGillivray's Warbler, several Common Yellowthroats and Lincon's Sparrows, but hardly any Song Sparrows! And none of them were color banded - perhaps all of our summer SOSP are gone.