YLG (L. michahellis michahellis) 13⁺cy CU9, Missouriweg - Maasvlakte, the Netherlands, April 29 2002 (51.59N,04.02E).

At least from the early 90's, but maybe during the 80's as well, Yellow-legged Gulls (L. michahellis) can be found in the breeding colonies of Europoort, Rotterdam. These adult YLG may breed with both Herring Gulls (argenteus) or Lesser Black-backed Gull (graellsii or 'Dutch intergrade'). If possible, the offspring are ringed as well. This adult YLG was ringed as adult at the nest, June 10 1994, now at least in 13cy. A metal ring was added as well, left leg "Arnhem 6.028.686".  

As is common in YLG, the orbital ring is red and the red spot on the gonydeal angle extends on the upper mandible (rare in argenteus). Note the yellow legs and the mirror on p10, merging with the white tip. The grey tone of the upper-parts is slightly paler grey than in British LBBG graellsii. 

(mixed pair: male LBBG x female YLG)

(2002 male LBBG)

Note the small black markings on both the upper and lower mandible. It might be a young adult male.

(2003 male LBBG, partner of CU9)

CU9 is breeding on the exact same spot as last year. The male has a red orbital ring and a clear yellow iris without black speckling. It has some faint black on both the lower and the upper mandible and the red gonydeal spot is confined to the lower mandible. Both P9 and P10 have a mirror, P10 has a large mirror and the complete moult hasn't started yet: P1 is still present by June 02 2003.

Successfully raised two youngs.

(2004)