Thayer's Gull (thayeri)

(last update: January 22, 2013)

Thayer's Gull 1st cycle (2CY), mid-January 2014, central California, US. Picture: Amar Ayyash.

Visit: Amar's blog for many more images!

Present flock of about >600 birds (170 1st cycles, 100 2nd cycles, 40 3rd cycles, 350 adults).

Overall barred feathers and strong bill with obvious gonydeal angle.

Blackish bill, dark iris.
First gen flight feathers; primaries with neat fringes confined to the tip of each feather.
Tertials have solidly brown centres (some notching near tips in this bird), dense barring on upper and undertail coverts, tail most dark with some proximal vermiculation on outer rectrices.
Typically scapulars are three-tones: pale brown centre, dark sub-terminal line and pale fringe (fresh new upper scaps have anchor pattern).