Ringed as adult male at Zeebrugge (51.21N 03.11E) on June 08 2000 . A male (code M1, based on comparison with its partner), aggressive in defending its territory at the colony of Zeebrugge. This individual shows only very little black markings on both upper mandible and the cutting edge of the lower mandible early May, but such markings were not detected on May 29 2003 (although distance and light conditions were worse on that date). The iris is clear yellow. The red gonydeal spot continues on the upper mandible. P1 is still old by May 29 2003, but head moult is in progress.

This sub-adult BWAD from Zeebrugge is now paired with green AH6, born in the colony Maasvlakte, the Netherlands (51.59N, 04.02E). AH6 was ringed as pullus on July 20 1992, now in 12cy and believed to be a hybrid Yellow-legged Gull (michahellis) x Herring Gull (argenteus). This couple nicely demonstrates the migration of LBbG from the Netherlands to the growing colony of Zeebrugge.