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

(last update: December 2015)

Black-tailed Gull (crassirostris) sub-adult, August 19 2005, Tokyo, Japan. Picture: Trunck Wood.

Please visit Wood's photostream on Flickr.

Black spots on secondary centres indicate sub-adult bird. Bird in complete moult: P1-P5 new, P6 growing, P7 missing, P8-P10 old. While P6 is growing, the moult in the tail has started: central tail feathers have been shed. This tail moult will develop centrifugal, i.e. from the central tail feathers outwards. Soon (within a week) moult in the secondaries will start as well, initiated at the outermost secondary S1.