Barn owl nestbox

• Owls

There are many factors to consider when choosing a bird of prey nest box. Please read our advice carefully before purchasing. The nest box is supplied flat packed but is simple to assemble and comes with full instructions.

*Please bear in mind that barn owls are a Schedule 1 protected species and can only be inspected during the breeding season by someone with a licence.

Outside the breeding season the boxes can be checked for maintenance and cleaning.

Installation and health and safety considerations

Owners must choose a suitable site (please see the following section) and then plan how to install the box safely.
Given the varying locations and methods for installation, the RSPB does not provide detailed instructions for installing the box.
Some general principles to consider for each location include:

• Take account of the weight and bulk – how are you going to get the box safely up to the place that you have chosen?
• How will it be fixed in place – do you need to do any preparation first?
• Do you need others to help – e.g. holding ladders, passing tools and equipment, keeping others away.
• Do you need any protective clothing – e.g. the person below holding the ladder may be advised to wear a helmet!

Where to site your box

Barn owls are not woodland birds but are typically birds of open farmland. Natural sites used by barn owls are typically tree hollows and farm buildings which are close to unmanaged grassland areas in fields and ditches. These habitats are home to the barn owl’s primary food source, field voles plus other small mammals such as bank voles, wood mice and rats.

This nesting box is a universal design for offering inside farm buildings or on trees. If fixing to a pole ensure that extra perches are added to give extra space for emerging fledglings.

Interior siting in a barn or similar building

• Position the box as high as possible in the building but leave at least an 18” space between the roof and the top of the box for roosting owls and owlets (39” in if a prefabricated building with a metal or asbestos roof).
• Fix box at top and bottom fixing points with a suitable strong fixing.
• Ensure that the box entrance is visible to an owl entering the building and that there is a clear flight path to it.
• Site the box where emerging fledglings can reach beams or similar areas - add extra perches if necessary.
• Ensure there are at least 2 permanent means of entrance and exit to the building for the owls.
• Barn owls become used to regular comings and goings but avoid siting where the box is exposed to irregular activities

Exterior siting on a tree or the side of a building

• Fix to a suitable tree (not in woodland), on a pole or in a hedgerow/tree on woodland edge with an open outlook.
• Face the entrance East/NE/SE - away from the prevailing wind.
• In all cases the box should have a clear flight path to the entrance.
• Height of the top fixing point should ideally be between 3 - 5m (10 -16 ft)
• The flat roof design of the box gives an additional exercise area for growing chicks, but where possible, boxes should be installed where perches such as branches are available for emerging owlets.
• Fix box at top and bottom fixing points using a suitable strong fixing and if necessary, brace the box using additional fixings. Ensure all fixings are tightened securely but do not over-tighten against the bend, as this may damage to the box.
• Avoid siting the box above water-filled ditches, which may present a hazard to emerging chicks if they fall from the box.

Additional Advice

• Do not site box within at least 1km (½ mile) of a busy road or motorway due to the risks posed to low-flying barn owls by fast moving traffic.
• The chances of a barn owl using the box will improve if the surrounding countryside has areas of unmanaged hunting habitats for the owls where they can find small mammals.
• There is no need to add any ‘nest material’ - pellets from the owls will gradually build up and when trodden down by the birds will provide a suitable ‘scrape’ for egg laying.
• Providing a second box nearby offers a roost for the male during the breeding season.

Signs of Occupancy & Monitoring

Barn owls are usually active at dusk through to dawn, and they will often remain out of sight during the day if they start using a nest box.

• Look for pellets and/or whitewash below box or on the box itself - these are signs of potential occupancy.
• Watch for owls flying to and from the box at nightfall (keep your distance).
• Listen for hissing from the box or adults bringing food into it - these are good indicators of breeding activity - if an owl on its way to the box with food sees you, it may hold back, so keep your distance as young may be waiting for valuable meals!
• Barn owls will sometimes breed more than once in a year, so box could be active all through the spring/summer.
• Some years egg-laying can begin as early as April
• Barn owl boxes will occasionally be used by little owls, kestrels and even tawny owls.
• Consider fitting an infra-red camera to the box - this is a great way to monitor it without disturbing the owls.

Disturbance and Inspection

Barn owls in the UK have special protection and are classified as a Schedule 1 bird under the Wildlife and Countryside Act (1981). It therefore necessary to follow strict guidelines when considering any maintenance or inspection of your barn owl nest box:

• It is illegal for any unlicensed individual to disturb or photograph barn owls at the nest whilst they are breeding. This law applies to all individuals, including the owners of nest boxes.
• Inspection or maintenance of the nest box by un-licensed individuals should take place outside the breeding season, which is generally regarded as between November and January.
• Barn owls will tolerate a certain amount of regular human activity around the box and will usually sit tight, as long as there is no contact with the box or tree itself. However, any disturbance should be minimised in the first year.

Maintenance

• An annual inspection of the box outside the breeding season (Nov - Jan) is recommended.
• It is best to inspect boxes an hour before dark and during dry calm weather.
• If there are visible signs that an owl is in the box, monitor it from a distance - dusk is a good time to do this.
• Boxes filled with twigs or leaves by grey squirrels or birds should be cleared out (but please ensure that any birds’ nests are not in use). If there are owl pellets in the box, a small quantity can be left in the box as a lining. It is advisable to wear a dust mask and heavy duty gardening type gloves when clearing out boxes.
• Any bird or squirrel disturbed in a box will probably exit rapidly - be aware of the risks of this when at the top of a ladder.
• Our boxes are treated with an eco-friendly water based preservative where needed - if re-treating ensure that only environmentally friendly water-based coatings are used.