Thayer's Gull (thayeri)

(last update: January 22, 2013)

Thayer's Gull 2nd cycle (3CY), 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).

Bi-coloured bill hardly developed in this bird (much like 1st cycle here), dark iris, and the legs are clean, deep pink.
Second gen flight feathers. The underside of the longest primary (P10) is visible: no sign of a mirror here (typical of Thayer's and unlike Kumlien's). Primaries are darkest part of the bird, dark brown, with neat fringes confined to the tip of each feather.
Typically, the closed wing is predominantly brown and the tertials have solidly brown centres, and rather uniform mid brown greater coverts. But this bird more contrastingly patterned with darker shaft streaks on median coverts and vermiculation on tips of tertials and all visible greater coverts.
This bird has a few greyish feathers in the scapulars.