Slaty-backed Gull (schistisagus) / オオセグロカモメ / 큰재갈매기

(last update: December 2015)

Slaty-backed Gull (schistisagus) 2nd cycle (2CY), September 16 2009, Hokkaido, Japan. Picture: Hannu Huhtinen.

Active complete moult, moulting to 2nd cycle. All coverts and tertials replaced for 2nd gen, overall plain greyish brown with no hint of vermiculated pattern. New mantle feathers show the upperpart grey tone of adults, older scapulars and inner wing-coverts bleached to whitish, with dark shaft. Pale iris.