Great Black-backed x Yellow-legged Gull

[Ingo Rösler]

Hi,

this bird was ringed as one of three pullus of a mix pair Great Black-backed (male) X Yellow-legged Gull (female) at 21.05.2010 in Frankfurt.
2009 this pair was breeding for the first time: 2 chicks / 1 got fledged
2010 3 chicks / all got fledged; 1 with yellow colourring, 2 only metalrings; 1 metalringed was found dying at 11.07.2010 in Frankfurt
2011 2 chicks / 1 goot fledged (yellow colourring) last recording 31.07.2011 in Frankfurt

In early juvenile stadium , these birds look more similar to YLG than GBBG.
In sice they were slightly taler than a YLG.
This was the first recording after ringing of this bird.

The grey of mantle is darker than YLG but much paler than GBBG, alot of mantle feathers already moulted into grey of this 2cy bird just like YLG (further than GBBG).
Tertials more like GBBG with broad irregular white tip.
Broad tail-bar more like YLLG.

regards
ingo