Thayer's Gull (thayeri)
(last update: January 22, 2013)
Thayer's Gull 1st cycle (1CY), December 14 2008, Half Moon Bay, California, US. Picture: Chris Gibbins.
Visit: Chris's weblog.
Bird in juvenile plumage. Note extensive dark tertial centres and pale crescents on primary tips. Almost completely uniform dark texture on underparts and in the neck. Black bill. Heavily / densely patterned undertail coverts.
