Following on from an exceptional breeding season in 2007, recorded numbers of Suffolk’s breeding barn owls have soared to their highest level since a national census was completed in 1932. With records still to come in, it is likely that the total number of breeding pairs will exceed 200. Barn owls have now recolonised former strongholds and are seen in places where they have been absent for over 20 years.
“It’s not all good news however, as heavy rain in early spring resulted in the owls’ principal prey items - short-tailed voles - being in short supply with the result that there have been low broods this year with no second broods at all, especially in the Waveney Valley. However this year’s owlets will reach maturity quickly and hopefully be able to mate this coming spring,” says barn owl specialist Steve Piotrowski who heads the Suffolk Community Barn Owl Project – a partnership between Suffolk Wildlife Trust and the Suffolk Ornithologists’ Group*.
The county's barn owl population before the 2nd World War was estimated to be around 350 pairs, but from around 1945 numbers fell dramatically, a decline that continued through to the 1980s with barn owl populations reaching an all-time low of 125 pairs in 1991.
During the early 1900s the barn owl was thought to be well distributed and considered to be the most common of the owls. The owls' favourite hunting grounds include rough grassland where it finds its quarry of small mammals such as voles, mice and shrews. However, since 1939 a hefty 96% of Suffolk's unimproved grassland has been lost. This has been due to the fragmentation of rough grassland caused by modern agriculture, and the intensive management of field margins, watercourses, hedgerows, woodland edges and roadside verges.
“The current situation highlights the importance of small mammal habitat such as rough grassland for barn owl and a lot of my time is spent visiting farms to advise on the management of such grassland and suitable barn owl box locations. This summer the Project has monitored 780 barn owl boxes throughout Suffolk and there are lots of orders for new boxes so this should rise to 850 in 2009.”
A reduction in farmyard foraging due to improvements in the methods of handling grain and the lethal effects of organochlorine pesticides have also taken their toll. The construction of major new road networks not only fragmented habitat but also enabled traffic to travel faster, resulting in more road deaths. It is this loss of habitat that has largely been to blame for the barn owls' decline. As the population recovers, the provision of properly sited nest boxes – to which the barn owl take readily - is relieving competition for the few remaining natural nest sites.
As one of Suffolk's characteristic species, targets for the barn owl have been included in Suffolk's Biodiversity Action Plan to stimulate conservation action. “If anyone out there would like to help the Suffolk Community Barn Owl Project, they can adopt a box for £20 a year - it makes the perfect gift. In addition to an initial certificate and barn owl box allocation, each year we will send you an e-newsletter with details of occupation and breeding success.”
For more information contact Oka at Suffolk Wildlife Trust on 01473 890089 or visit www.suffolkwildlifetrust.org/barnowl.html