Many hole-nesting bird species have suffered declines in recent decades, and although planting trees can provide a long-term solution, in the short term a variety of nestboxes can help make good the shortages. Different species, of course, like different sorts of boxes:
Hole-fronted boxes: Great for tits, sparrows and even Nuthatches. Make sure your box is squirrel and woodpecker-proof by fixing a metal panel around the hole to stop them enlarging it to gain access to eggs and young. Boxes can be placed against buildings, on posts, or fastened securely to tree trunks.
Open fronted boxes: These are used by Robins, Wrens, Spotted Flycatchers and the like. They generally need to be situated in a more covered position, both for protection against the elements, and to deter predators.
Wall-mounted boxes: These suit eave-nesting species such as House Martin (below) and Swift, but some need considerable installation work – Swift boxes, for example, are sometimes built into a new structure. If you have outhouses or sheds which can be left partly open, Swallows, Wrens and other species may nest inside.
The best time to put a new box up, or to clean out a previously used box, is late summer or early autumn.