During an ecological appraisal close to marshland in Kent, one of our ecologists was lucky enough to encounter a barn owl, watching this magnificent bird hunt for several minutes. This ghost-like apparition flew silently by whilst searching for prey, such as field voles, shrews and woodmice. Interestingly this encounter was well before dusk on a cold January day.
According to recent and historical studies, diurnal barn owls are on the increase in the UK¹. This may be a worrying trend, particularly since this behaviour in owls does not appear as common in other countries, such as Germany and France¹. The main theory for day flying owls is a shortage in prey availability² which forces these birds to hunt whenever the opportunity arises. In freezing winter conditions, hunting becomes even more difficult for the barn owl, as voles are less likely to be active at night.
In addition, whilst specialised fringed and hooked feathers allow them to glide silently and slowly above the ground, they are not particularly water-proof, which severely limits their hunting capability during spells of rain. This can be catastrophic, particularly for young birds who have not yet established a home range with well-known foraging sites. Historically, during bad weather, barn owls would have stayed close to a farm building to hunt rats and mice, however, modern grain storage has dramatically reduced this abundance of easy prey.
Whilst it is known that this species can successfully breed using boxes integrated with barn and farm building conversions to substitute natural nesting sites³, the impacts resulting from the loss of key foraging areas are usually less apparent. Since barn owls are only legally protected from disturbance during the breeding season, the wider habitat that they depend on for survival can often be overlooked.
Optimising hunting habitat is the key to their winter survival. This means that the retention and enhancement of strips and patches of good quality, tussocky grassland within suburban and rural developments is likely to benefit the local barn owl population.
Given the chance, barn owls can be adaptable and opportunistic hunters, so with careful design at an early stage their needs can be integrated into development proposals. For some schemes, this species can even benefit from development. For example, the installation of solar farms on former arable land can offer barn owls new hunting habitat in the form of meadow grassland beneath the panels as well as an ideal perch from which to launch².
If you are planning a barn conversion or rural development, please contact us today to discuss barn owl survey and mitigation.
1. Martin,. J. 2013. The daylight activity of flying barn owls. British Birds.
2. The Barn Owl Trust 2016. www.barnowltrust.org.uk
3. English Nature. 2002. Barn owls on site: a guide for developers and planners.