VEGELIN JCG (1989) Short contributions: Breeding of Herring Gulls Lams argentatus and Lesser Black-backed Gulls Larus fuscus on roofs in IJmuiden. LIMOSA 62 (3): 154-155.

European Herring Gull Larus argentatus Lesser Black-backed Gull Larus fuscus Mass breeding of Herring Gulls (71 pairs in 1987, 139-142 pairs in 1988) and Lesser Black-backed Gulls (2 pairs in 1987, 4-7 pairs in 1988) in a mixed colony on roofs of buildings in the IJmuiden harbour area (Noord-Holland) is reported. Roof nesting in the Netherlands has been reported only incidentally for the Herring Gull and never for the Lesser Black-backed Gull.

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