Sorry I'm a disciple of Japanese experts.
I made my comments indeed after taking consideration of bleaching effect of the tropical sun, which makes plumage a bit paler than book drawings as winter advances into a new calendar year.
I concede I've overlooked the bill tip which is a bit pale.
In 'A gull identification handbook revised edition' by the Japanese Father & Son, in which the accuracy of the drawings are excellent, the bill tip of a Vega immature should look red but the bird in question is just pale.
For immature Vegas the upperbody's steakings -head and necks mainly - they are palest kind of brown and looks thick, again according to the book's drawings and for the Heuglins' they should be narrow and shorter. For Vega immatures, the light brown of the underbody should be still there for indirect and therefore weaker sunlight effect but the bird in question is nearly white.
If the bird was a Vega, then it looked probably a 3rd winter bird. In this case, the outer tail feathers should look white for the dark tail band is not so intense and reaching the side as the photo showing the bird flying.
Whether Heuglins tend to retain their streakings more than Vegas' immatures I do need more observation.
Others points are, Heuglins' legs should be paler than Vegas' and underwings of the latter should show some grey tinge but the photos do not show this.
Indeed I would do more field observation but maintain that my points are not without grounds.
S L Tai
[ Last edited by tsheunglai at 14/01/2014 23:20 ]
