BOUWMEESTER J & DIJK J VAN (1991) Short contributions: Roofnesting of Common Tern Sterna hirundo at Aalsmeer.. LIMOSA 64 (1): 25-26.

In 1990 25 pairs of Common Terns Sterna hirundo bred on the immense flat roof of the flower-auction building in Aalsmeer (close to Schiphol-Amsterdam). The species has probably used this site for nesting since 1985 or earlier. In the eighties Common Terns established two colonies (1990: c. 800 and 35 pairs) in the middle of traffic roundabouts in Amsterdam. Probably due to disturbance there some terns nested on roofs close to the smallest of these two colonies (1987: I, 1988: 2). The Aalsmeer terns may also have orginated from these new colonies on roundabouts near Amsterdam.

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