Possibly the first known colony of Black-headed Gulls
Chroicocephalus ridibundus on a roof in Amsterdam (Hoofddorppleinbuurt, 5 June 2018). The total number of nests remains unknown as they nest there between solar panels. A best guess... about 10 nests?? (update: turns out they're already nesting 'in good numbers' on roofs in the Westhaven area (annually?) and Amsterdam Zuidoost (2 pairs in 2015, thanks Ruud!).
About three pairs of Common terns
Sterna hirundo nest among the Black-headed Gulls.
Herring Gulls
Larus argentatus (photo above) and Lesser black-backed Gulls
Larus fuscus also nest in the area, but their nests are more widespread and difficult to detect.
