The barn owl is a truly awe-inspiring bird, as anyone lucky enough to have witnessed this silent white hunter will testify. They are mainly confined to lowland farmland, and their diet preference for small rodents has earned them the nickname ‘farmer’s friend’. Sightings, however, are few and far between, with recent estimates suggesting there may be fewer than 50 breeding pairs in Northern Ireland. This alarming statistic places the barn owl high on the priority list in terms of conservation efforts, and UWT is the lead partner in delivering action for the species.
Barn owls in Northern Ireland
Barn owl numbers have never been high in Northern Ireland, as our country represents the edge of its north-western range in Europe. Historically low numbers are due to our rather damp, Atlantic-influenced climate: barn owls find hunting difficult in wet weather and struggle to survive cold winters. However, there is no doubt that the population has plummeted in the last 40-50 years, leaving the species extremely vulnerable to extinction.
How do you know it's a barn owl?
Three owl species are found in the wild in Northern Ireland: the barn owl, the long-eared owl, and the short-eared owl. Despite the distinctive colouration of the barn owl, it can be confused with other species, particularly if only glimpsed for a few seconds. Barn owls are rarely seen during the daytime; sightings at dusk or dawn, or in the middle of the night, are much more likely. Their underparts appear white overall, and a good view of the owl may reveal its honey-coloured upperparts. The adult call, an eerie screech, is distinctive, but even more unmistakable is the loud snoring sound the chicks make in mid-summer.
Habitat is another useful indicator. Barn owls may be seen hunting over open countryside in lowland areas, scanning fields, grassy woodland edges or marshes for small rodents and other food items. In Ireland, the barn owl's diet is thought to comprise mainly mice, pygmy shrews and small rats, but they do eat frogs and even starlings when food is scarce.
Their habit of nesting in disused farm buildings or ruins is well known, with actual nests consisting of a pile of debris (pellets containing regurgitated bones and hair from prey items, and feathers) on a convenient ledge. Less well known is their use of cavities in old trees as nest sites - generally isolated, hedgerow, or woodland-edge trees will be used, as barn owls tend to avoid dense woodland.
What is being done to protect the barn owl?
A barn owl Species Action Plan (SAP) for Northern Ireland was published in 2006, detailing the work required to increase the barn owl population and expand its range. UWT is the lead partner in the implementation of this plan, and a working group has been established as a framework for achieving this.
Barn owl SAP steering group minutes and documents are available to download below:
Minutes of Meeting March 2008
Minutes of Meeting September 2008
Minutes of Meeting February 2009
Sightings Appeal
Barn owls are very elusive birds and are extremely scarce, so there are huge gaps in our knowledge in terms of their ecology, distribution and behaviour. You can help to fill in some of these gaps - if you have seen a barn owl in your area or know of any active roost or nest sites, please contact Maeve Rafferty on tel. 028 4483 3966 or email: barnowls@ulsterwildlifetrust.org
This vital information will be used to identify hotspots or 'target areas' for barn owl work. Please be assured that records will be treated with sensitivity and can be kept confidential on request.
Barn Owl Fieldworkers Scheme
This initiative stems from a meeting held in May 2008, organised by UWT and attended by barn owl enthusiasts across the country. The scheme aims to harness existing volunteer fieldworkers to re-survey historical nest locations and survey new or possible breeding or roosting locations. Fieldworkers have to date been engaged in two main areas of work: undertaking a nest box audit and searching for new nest/roost sites in response to the sightings appeal. Click here for more information on the scheme.
There were 24 registered Barn Owl Fieldworkers working all over Northern Ireland in 2009. Information was provided on 50 nest boxes, and more than 40 sightings were followed up on. Two new nest sites have been discovered as part of the scheme, although one of these failed last year due to the death of the female (see Careful Rodent Control section below). Pellets collected from nest and roost sites have been analysed and recorded, and eventually this work will fill those knowledge gaps concerning barn owl diet and habitat preference in Northern Ireland.
Barn Owl Survey 2010
A new survey will be launched this year, based on the study of selected 2 x 2 km² grid squares (tetrads) located within barn owl hotspots. These hotspots have been identified by mapping breeding season records of barn owls, from a variety of sources, over the past ten years. We hope to have results available from this first survey season in winter 2010.
Other ways to help
Habitat Provision
Farmers and landowners can make a massive contribution by providing suitable feedling and nest habitats. A leaflet with guidelines on both is available on request from UWT or RSPB, and your local DARD agri-environment advisor will also be able to provide guidance.
Nest boxes can be provided, but Ulster Wildlife Trust recommends nest boxes only be erected in areas where barn owls have been sighted, and ideally in areas lacking natural nest sites. Design plans for barn owl nestboxes are available to download for free from this website:
Barn Owl Trust http://www.barnowltrust.org.uk/infopage.html?Id=42
'Boxes, Baskets and Platforms', a book on artificial nest sites for owls and other birds of prey, is available to purchase from the Hawk and Owl Trust website http://www.hawkandowl.org/
Click here for further information on which nest box design to use, where to site them and how to erect them. If you've erected a nest box, please let us know by emailing barnowls@ulsterwildlifetrust.org
Careful rodent control
Barn owls are susceptible to secondary poisoning by eating rats or mice which have ingested quantities of rodenticide. While barn owls will only take live prey, there is a risk they may consume a rodent before it dies. It only takes three poisoned mice or rats for the chemical, usually an anticoagulant rat poison, to build up to toxic levels in the barn owl.
Although there is no evidence to suggest that rodenticides are a factor in the decline of the barn owl in Northern Ireland, the sub-lethal effects of exposure to these chemicals are poorly understood. Two barn owl carcasses found in Northern Ireland this year, one of these the female from a known nest site, were found to have trace quantities of commonly used rat poisons. This demonstrates for the first time that our barn owls are being exposed to rodenticides, a fact which is well documented in other parts of the UK.
If you have an infestation of rats or mice, please follow the Campaign for Responsible Rodenticide Use Code on the Think Wildlife website. This set of simple guidelines will provide you with all the information you need to treat the infestation effectively, whilst reducing the risk of poisoning to barn owls and other wildlife.
Found a dead barn owl?
Report this to UWT immediately, so that the carcass can be sent for Post Mortem analysis via the Predatory Bird Monitoring Scheme.
Useful links
http://www.habitas.org.uk/priority/species.asp?item=48
http://www.ni-environment.gov.uk/biodiversity/sap_uk/sap_ni.htm
