Sparrowhawk (Eurasian Sparrowhawk)
Accipiter nisus
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Distribution Britain 2,178 (19.6%) Ireland 663 (-17.0%)
Numbers breeding: Britain 32,000 — Ireland 11,000 European status: 155,000 (28% in Britain and Ireland =1) British population trend: recovered — now stable? (+294% CBC){+162%} How likely are you to record it? 600 squares (13.7%) Ranked 58[57=] |
This scourge of the small woodland birds now breeds throughout Britain and Ireland, except the Western Isles, Shetland and other areas without trees. This was the situation to 1950 despite the best attempts of gamekeepers to destroy them. The only of success was that the populations in some areas increased during the two world wars. When many keepers were away on other duties. In the late 1950s it became clear that they had crashed and were missing from large areas, particularly of South-east England. The culprits were the organo-chlorine pesticides like Dieldrin, Aldrin and DDT, and their metabolites, which built up in the food chain and poisoned the top predators. This caused many deaths and disrupted the female's calcium metabolism leading to many failed breeding attempts. The chemicals were banned and the birds made good most of their losses (not yet complete in the South-east). They also took to the new conifer forests, where they have to put up with Goshawk predation, and started breeding in towns. Full recovery seems likely.
Newton, I., Dale. L. & Rothery, P. 1997 Bird Study: 44, 129-135.
From
The
State of the Nations Birds
Copyright © 2000 by Chris Mead