OUWENEEL GL (1980) Short announcements: Autumn-concentration of Pochards Aythya rerina on the Haringvliet. LIMOSA 53 (3): 105-105.

Autumn-concentration of Pochards Aythya rerina on the Haringvliet Ventjagersplaten Before the enclosure of the estuaries in the Deltagebied the Pochard Aythyaferina visited these waters only in small numbers. After the enclosure of the Haringvliet (ZH) in 1970 numbers have increased. The Ventjagersplaat is the most important concentration-area where up to 22 500 Pochards can be present in October (table I). Presumably the birds feed elsewhere during the night, resting on and between the banks on the Ventjagersplaat during daytime.

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