OUWENEEL GL (1985) Short contributions: Summering Red-necked Grebes Podiceps grisegena on the Grevelingen. LIMOSA 58 (2): 74-75.

Red-necked Grebe Podiceps grisegena In 1982-83, from July till September a flock of Rednecked Grebes was observed in the eastern part of the Grevelingen, Delta area (maximum 22 birds on 19 September 1982). In 1984, on every visit there were Red-necked Grebes present (maximum 7 on 7 July). During May-June 2-3 birds were present. Flocks of non-breeding Great Crested Grebes P. cristatus are summering at the same place. During July- August up till 25 Black-necked Grebes P. nigricollis may occur. The Red-necked Grebes usually did not mix up with other grebes

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