Sunday, 1 December 2013

13 is unlucky for the wise Barn owl.

A hunting Barn owl
2013 appears to have been the poorest breeding season for barn owls in Britain since 1958. This year's round of 73 Annual Monitoring Site visits by the Barn Owl Trust has now revealed the extent of the devastation. On average nesting occurs at 51% of sites, this year's figure is a mere 12% and 47% of nest sites are completely unoccupied. At the 12% of sites where pairs have managed to survive and breed, the average number of young in the nest is just two rather than the four or five that are needed for population recovery.

This national scenario was played out near to where I live in Hampshire, when a neighbouring farmer found a Barn owl back in June, lying dead on a clutch of eggs in one of the nest boxes he had put up specifically for it. The very late cold spring, lack of small mammals and the huge effort of egg laying, had all been too much for this particular female.

A few regions of eastern England did buck the trend however, with between one and two-thirds of traditional nest sites producing young with average broods of between three and five.

This is a real setback for a breeding population which, since the turn of the century has probably risen from around 4500 pairs to nearer 8000 pairs in Britain, maybe more. The BTO’s Breeding Bird Survey - which records the population trends of UK's breeding birds, supports this increase in numbers. It reports an almost three-fold increase between 1995 and 2012, whilst data from its new Bird Atlas suggests that this bird has also seen an almost 70% increase in range expansion in Britain since the Barn Owl Survey of Britain and Ireland in 1987.

With the enormous abundance of food in the form of berries, nuts and fruits this autumn, I imagine that many small mammals will fare well over-winter and may be in good numbers come next year. If the British weather can resist from showing off all its extremes in 2014, and just deliver an average year , then hopefully the delightful Barn owl will bounce straight back with a good breeding season, and continue its recent success story.

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