American Herring Gull (smithsonianus)

(last update: October 30, 2015)

Coordinators:
Amar Ayyash (US)
Bruce Mactavish (Canada)
Dave Brown (Canada)
Mars Muusse (Netherlands)

Slaty-backed Gull (schistisagus) 3rd cycle (3CY), September 16 2009, Hokkaido, Japan. Picture: Hannu Huhtinen.

Active complete moult, moulting to 3rd cycle. Very 'untidy' looking bird. P10 old 2nd gen, P1-P7 replaced for adult-like 3rd gen primaries. Much black on bill, pale iris. Old tail-feathers with much black, bleached; the central rectrices dropped. In preening bird, note the old 2nd gen secondaries, lacking the bold white tips present in new 3rd gen feathers.