A Veritable Almanac!
Birds that nest in holes will readily use the bird box described here; there is a need for suitable nesting places for birds with gardens playing an increasingly important role. To highlight this need, in my garden Blue Tits made a nest in a hole left in the wall by the removal of a waste outlet pipe. The hole was left exposed and the nest was made in the cavity between the two courses of bricks.
Click on Plan below to make bigger!
I thought perhaps this would be an ideal location for the placement of a more suitable wooden nest box. I added a trellis to grow honeysuckle up it and perhaps eventually partially conceal the box. Remember to leave the entrance hole clear, a Blue Tit likes a clear path to the entrance of the box.
If you feed birds that come into your garden keep the feeding area well away from potential nesting sites. The feeding activity around a bird table could put nesting birds off.
My Version of the nest boxes made from 6 inch by 1 inch (150mm x 25mm) rough sawn pressure treated wood available at many DIY stores. Though not recommended by various ornithological societies, I have used pressure treated wood for my bird box. Treated timber used to be a problem because of the arsenic content. This is not the case today; ordinary members of the public who buy pressure treated wood have a much safer product, but be cautious about using old reclaimed wood that may be of the CCA* variety.
*CCA (Chromated Copper Arsenate)
If preferred use ordinary untreated wood, I once made a bird box from Iroko a very hard wood which has excellent natural preservative qualities. This wood can be used and left untreated. The resulting bird box I made from this has been used for thirty years. Initially by Blue Tits but eventually Great Tits enlarged the hole and have been using it successfully for a great number of years.
The usual precautions should be taken when cutting and machining woods.
Iroko has the potential to cause asthma, dermatitis and nettle type rash.
Here is an open fronted nest box I installed about three feet from the ground. I’m hoping a Robin will take up residence when the pyracantha (firethorn) has grown around it to camouflage it from predators.
If there is no natural shelter, it is best to mount a box facing somewhere between south-east and north, to avoid strong direct sunlight and the heaviest rain. The box should be tilted slightly forwards so that the roof may deflect the rain from the entrance.
Hole-Size Guide for Bird Boxes
25mm Blue Tits, Coal Tits and Marsh Tits
28mm Great Tits, Tree Sparrows and Pied Flycatcher
32mm Nuthatches, House Sparrow
45mm Starling (Larger Box Required)
In a suburban garden the most likely birds to use a hole-type nest box are the Blue Tit and Great Tit.
Larger mature gardens leading on to surrounding woodland may attract other species like Coal Tits* and Nuthatches.
*Coal Tits will nest low down in the hollow of a tree from a height of about 1 metre!
Remember do not put perches on bird boxes they’re not needed and potentially help predators to gain access into the box.