SCHOUTEN C (1982) Short contributions: Occurrence and passage of the Black Tern Chlidonias niger in the Ilsselmeer area. LIMOSA 55 (2): 56-58.

Black Tern Chlidonias niger In August 1981 counts of Black Terns were made in the IJsselmeer area. The birds were counted during their flight to three roosts. On 8 and 15 August 55 000 Black Terns were present in the area (fig. 1). Seventyfive percent of the terns came into the Oostvaardersplassen between one hour before sunset and sunset (fig. 2). The large number of Black Terns exceeds greatly the NW. European breeding population. Therefore the majority of the birds must come from Eastern Europe (Poland, USSR).

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