data on the wintering of the rook, corvus frugilegus linnaeus, 1758 (aves: corvidae) in plovdiv, bulgaria

In the current study we report a short summary on the wintering of the Rook in the town of Plovdiv. During our field study we estimated that no less than 29 706 ± 8722 Rooks are roosting in Plovdiv. Our findings revealed that the number of wintering individuals of this species has increased in a ten years period by 35 times in comparison to a previous study and reached a maximum in February when 59 280 Rooks were counted. Further investigation on that matter is needed so that the wintering pattern of the Rooks could be revealed entirely.