Black-tailed Gull (crassirostris) / ウミネコ / 괭이갈매기

(last update: December 2015)

Coordinators:
Kim Seog-min (South Korea)
Hideo Shimura (Japan)
Peter Adriaens (Belgium)
Mars Muusse (Netherlands)

Black-tailed Gull (crassirostris) sub-adult, August 01 2016, Chidiwa Unzen city, Nagasaki, Japan. Picture: Nobuo Fukushima.

Please visit Nobuo's website.

Bird in complete moult, moulting probably moulting into 4th basic plumage (4CY). P4 replaced and P5 growing, outer primary P7-P10 still old 2nd generation. No moult in tail. Note the old adult-like secondaries which are grey with large white tips, laking the dark centres you'll normally find in 2Cy and 3CY birds in mid-summer.