Rook
Corvus frugilegus
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Distribution Britain 2,237 (-0.4%) Ireland 919 (-1.2%)
Numbers breeding: Britain 855,000 Ireland 520,000 European status: 3,500,000 (39% in Britain and Ireland =1) British population trend: making up losses (+40% survey 1975-96) How likely are you to record it? 2250 squares (50.1%) Ranked 21 [8] |
By the end of the 19th century Rooks were almost everywhere that they could find decent trees to nest in. They colonised Orkney in autumn 1846 (bred 1847) and Lewis in October 1893 (breeding from 1895). Shetland was colonised in 1952. The numbers probably increased in Ireland earlier this century. The most dense populations are recorded in the Aberdeen area and through much of Ireland. Some colonies are very large — many thousands of nests — and there is no CBC index. However there was a survey of the UK population in 1975 which indicated a decline possibly connected with pesticide usage and even with Dutch Elm disease. However a repeat survey in 1996 indicated a recovery of 40% and the five-year BBS index (1994-98) increased by 10%. Good prospects for a species seemingly unaffected by changes in agriculture.
From
The
State of the Nations Birds
Copyright © 2000 by Chris Mead