The latest Breeding Birds Survey showed numbers of kestrels, often seen hovering over major roads looking for small rodents, plunged by more than a third between 2008 and 2009.
The dramatic drop came on top of long-term declines which saw kestrel numbers fall by a fifth between 1995 and 2008, the survey run by the British Trust for Ornithology (BTO) found. The ‘motorway falcon’, as the bird is known, used to be a common sight by roadsides. It was the subject of Ken Loach's famous 1969 film Kes, about a working class Yorkshire lad who has a pet kestrel. The bird also inspired Gerard Manley Hopkins' poem The Windhover.
However intensive farming and a run of difficult winters has led to a decline in the kestrel’s main food source which is small mammals like field mice and voles.
Grahame Madge, of the Royal Society for the Protection of Birds, blamed intensive farming for the fall in numbers. He pointed out that the decline in kestrels and sparrow hawks, questions the theory that the birds of prey are causing a decline in song birds. "Kestrels depend on rough grassland where they can feed on beetles, voles and other small mammals. They are a widespread countryside bird so these figures are alarming. We also believe pesticides and cold winters are behind the losses which have happened in a short space of time and are gathering pace," he said.
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http://www.telegraph.co.uk/earth/earthnews/7897122/Kestrel-numbers-fall.html