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

(last update: December 2015)

Slaty-backed Gull (schistisagus) 3rd cycle (4CY), March 11 2012, Choshi, Japan. Picture: Peter Adriaens.

Please also visit Peter's Pbase account and his Picasaweb albums for many more pictures!

3rd cycle with still black in the tail, brown on the tertials and a brown hue on several of the wing-coverts, obvious black on the bill and extensive winter streaking. Note also dark centres of greater primary coverts. Upperparts at this age often paler than in typical adult.

In flight: Primary pattern typical, with outer webs darker than inner webs, and with white tongue-tips on P5-8. The blackish outer webs of P8-10 reach up to the primary coverts.