Thayer's Gull (thayeri)
(last update: January 22, 2013)
Thayer's Gull 2nd cycle (3CY), February 03 2013, Boulder County, Colorado. Picture: Amar Ayyash.
2nd gen flight feathers, marked dark outerwebs of outermost primaries. No mirror on P10. Part of the scapular region grey, but all wing-coverts and tertials still pale brown. Dark iris and bi-coloured bill.
