Images taken during a visit to the gull colony of IJmuiden Forteiland, the Netherlands, on April 23, 2019, as part of our research project.
Shown are European Herring Gulls, Lesser Black-backed Gulls, and hybrids.
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European Herring Gulls
Now in its 20th calendar year.
With partner YBUW:
Lesser Black-backed Gulls
Born in the Rotterdam Maasvlakte colony but settling in IJmuiden.
With a messy plumage and a tertial spot. He is older than 14 calendar years.
Back from spending the winter in Morocco.
(Presumed) Hybrid Lesser Black-backed Gull x Yellow-legged Gull
With partner Lesser Black-backed Gull YCPL: