3085-2

L.R. Griffen, D. Skilling, R.T. Smith and J.G. Young

The 2010 Dumfriesshire Rookery Census: Including comparisons with the surveys of 1908, 1921, 1963, 1973, 1975, 1993, 2003, 2004 and 2008

Ornithology

TDGNHAS Series III, 85 (2011), 9(3.42 MB)

Abstract

Completion of the whole-county 2010 census of Rook Corvus frugilegus nests in Dumfriesshire is the most recent in a series which began in 1908. The results confirm that the decline in the number of Rook nests, first noted in 20035 , continues and now at 12,350 is at the lowest level ever recorded. This number is less than 50% of that recorded in 1993 when 25,489 nests, the largest number for the area was counted, meaning that the number of breeding Rooks has more than halved in the 17 year intervening period since that survey. In 1993, 22 colonies each held more than 200 nests, in 2010 (as in 2008) only one colony (not the same one) had more than 200 nests, symptomatic of the unabated fragmentation of large rookeries that has occurred resulting in ever smaller average rookery size, now just 33 nests per rookery.