VENNEMA P (1989) Seasonal variation in numbers of Blackbirds Turdus merula on a roost in Peize. LIMOSA 62 (4): 207-208.

Blackbirds Turdus merula Counts on a communal roost of Blackbirds at Peize (North-Drenthe) during January-December 1988 showed that the roost was used throughout the year (fig. 1). Peak numbers were reached in January, followed by a decline to a lower summer level. The numbers temporarily increased during late summer. The built-up of the winter population started in October and reached a peak in December.

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