The Barn Owl is a bird of open country such as farmland or grassland with some interspersed woodland. It prefers to hunt along the edges of woods. It has an effortless wavering flight as it quarters pastures or similar hunting grounds. Like most owls, the Barn Owl flies silently; tiny serrations on the leading edges of its flight feathers help to break up the flow of air over its wings, thereby reducing turbulence and the noise that accompanies it. The Barn Owl feeds primarily on small vertebrates, particularly rodents. In the UK the breeding season usually starts in late March to early April with nest sites being in tree holes and also buildings such as barns. The eggs hatch in the second half of May and the young are fledged during the second half of July although they will keep returning to the nest until August.
Barn owls, their eggs and young are protected under Schedule 1 of the Wildlife and Countryside Act 1981 (as amended). This legislation was introduced in response to a decline of approximately 70% in barn owl numbers since the 1930s. In addition, it is an offence to intentionally or recklessly disturb a nesting barn owl.
The requirement for a barn owl survey may be raised by the land owner, developer or planning authority. Usually, barn owl surveys will be requested in relation to planning applications to re-develop buildings located in rural surroundings. A barn owl survey involves an initial desk study to obtain records of barn owls and/or nest sites for the surrounding area followed by a site visit to identify evidence of barn owl roosting or nesting, such as live or dead owls, feathers, droppings, pellets, nest debris and eggs. This will then allow an assessment to be made regarding the type and level of use of the site by barn owls.
Where barn owl nest and/or roost sites are being redeveloped or destroyed alternative nesting or roosting provision has to be provided. Some larger scale projects may also impact upon barn owl feeding areas, in which case mitigation plans will need to include the provision of compensatory or additional patches of barn owl feeding habitat.