Photo 5: LBBG sub-adult, September 17 2001, Vuurtorenvlakte Maasvlakte, the Netherlands.

Probably a 4cy LBBG with a relatively small mirror on p10 and lacking the p9 mirror. P9 is still old, p5 is full-grown. The outer tail-feather (R6) is just visible near the full-grown tip of p5. Note the hardly visible black isolated spot near the centre, an indication for sub-adultness.