The once familiar house sparrow is in decline, and is now even absent from parts of the west of Northern Ireland. It is thought that this decline is due to a reduction in available invertebrates to feed their young, a reduction in grains and seeds to sustain them through the winter, and the loss of nest sites.
House sparrows are opportunist and will live wherever there is somewhere suitable to feed, roost and nest. We can help them out by providing these requirements. House sparrows will readily use nest boxes which can be made fairly cheaply and easily by even the least skilled handyman! Sparrows will not mind if the nest box is not a work of art, but please do ensure that the box is sturdy to prevent predators breaking into it, and that it is rain proof.
There are a number of suitable designs but if the diagram shown in the Mid Ulster Biodiversity Project poster (see in ‘Publications’ above) is followed, one 48 x 6 inch plank of timber, 0.75 inches thick, will make one nest box. (The planks used for fences are ideal). The size of the hole will determine what species of bird will be attracted to the box – house sparrows require a hole diameter of at least 30mm and ideally 32mm. The boxes can be either nailed or screwed together, and the roof should be hinged or screwed to allow access to the box to be cleaned out at the end of the year. A couple of small drainage holes should be drilled in the floor. The outside of the box can be treated with a wood preservative to extend its life, but do not treat the inside. Roofing felt can be fixed to the roof for added protection.
Although the birds will not use the boxes for breeding until the spring, you can put them up at any time of year. If put up in the Autumn or Winter, not only will this give them a chance to ‘weather in’, but some birds will roost in them on a cold winter night. Site the box in a sheltered position, on a tree or wall at about head height (or a couple of feet above if possible), preferably facing north-east to south-east. South facing boxes become too hot on a warm sunny day, while west facing boxes are open to prevailing wind and rain. As house sparrows are colonial breeders, several nest boxes can be put up in the same area, but do not put them right beside each other unless the entrance holes are facing different directions.
In addition to providing nest boxes, you can also help house sparrows by putting out seeds/grain over the winter, and by planting insect attracting flowers for the spring and summer. As chicks in the nest are fed almost exclusively on invertebrates, this will provide your sparrows with most of their needs. With any luck you could have your own colony, roosting, feeding and breeding in and around your garden, making a real contribution to helping one of our declining species.