Nest boxes for Barn Owls

Loss of nest sites is, without doubt, one of the major factors in the overall decline of the Barn Owl. It is hoped that these notes will encourage individuals and groups to undertake nest box schemes in a bid to counteract this decline. Remember, even a single nest box can mean survival for your local owls.

What is a nest box?
What is a nest box? Quite simply it is a substitute for the bird’s natural nest-site and also provides a safe retreat within large buildings and barns. Enclosed stone barns which have permanent access to the outside are, usually, the most favoured nest-sites but isolated trees and trees on the edge of woodland can also be effective nest-sites. Open Dutch-type barns are normally only used for roosting unless hay bales are left undisturbed in them. If a favoured roosting site is known, then this is the position to choose for your nest box. The operator can often find this position by looking for the accumulation of pellets (often beneath beams). If an Owl is able to use a box as a winter roost this will considerably increase the chance of it nesting there the following year.

Nest box Location
It is absolutely essential that the box should be rainproof. If the box is not watertight it should only be used in dry locations. If it is exposed to the elements only durable and watertight materials should be used. A poor box is worse than no box. Remember to knock nails flat and remove any lining paper or metal edges. A useful refinement is a baker’s tray sawn in half. This will provide two platforms about 18” in depth. One of these can be fitted to the front of the box so that owlets can come out and stretch their wings during development. Boxes should be secured as firmly as possible and sited high above the ground in the darkest corner, out of draughts and where there is permanent access. Since height is important the easiest time to erect the box is when the barn is full of hay bales. Where beams are available the box can be nailed to one of these with 3” nails to give a firm fixing. If the barn is a metal one the box needs to be firmly roped, wired or C-clamped to the steelwork. It will be found that every site demands its own solution. A layer of pine needles or similar material is a useful addition to the box when it is first installed. Once discovered, a box will normally be used every year and in this way populations can be significantly increased. But remember, the Barn Owl population is at a low ebb, so don’t despair if your box is not occupied immediately. It can sometimes take years.

Nest box Design
Boxes should be straightforward in design (see drawings below) and can be made from tea-chests, packing cases or similar types of boxes, or, if they can be obtained, wooden barrels.

Barn Owl nest box design document (in PDF format) can be downloaded by clicking: here

Barn Owl, Tawny Owl and Little Owl nest box design document (in PDF format) can be downloaded by clicking: here

Nest box information document (in PDF format) can be downloaded by clicking: here

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