Why Swifts Need a Helping Hand

Swifts are extraordinary birds. They spend almost their entire lives on the wing, eating, sleeping and even mating in the air. But when it comes to nesting, they are fussy. They need a high, dark cavity with an unobstructed entrance and a clear drop below. Traditionally, they used holes under the eaves of old buildings. Modern construction and renovations have sealed many of these gaps. The UK swift population has fallen sharply in recent decades. Putting up a specialised nest box is one of the most effective things you can do in a wildlife garden. It is practical, rewarding and surprisingly straightforward.

Choosing the Right Box and Position

Not all nest boxes suit swifts. A standard garden box with a small round hole is useless. Swifts need a specialist swift box, usually a shallow, rectangular chamber with an entrance slot or oval hole at one end. The box should be made from durable, weatherproof material such as exterior-grade plywood or a moulded wood-concrete composite. Avoid boxes with perches; swifts do not need them and perches can attract predators.

Position is everything. The box must be at least five metres above ground, ideally higher. It should sit under the eaves, tight against the wall, with the entrance facing roughly north, east or west. Avoid direct hot sun from the south, which can overheat chicks. Most importantly, the entrance must have a clear, unobstructed flight path. There should be no trees, wires or walls within a few metres. Below the box, there must be a clear drop of at least three metres. Swifts drop out of the nest and need air under their wings immediately. If they land on the ground, they cannot take off again.

Installing the Box Under the Eaves

You will need a safe ladder, a drill, rust-proof screws and a helper. Never work alone at height. If you are not confident, ask a qualified installer. Here is the sequence:

• Choose a sheltered spot under the eaves, ideally on a gable end or a wall that gets morning sun but not all-day heat.
• Hold the box in place and check the entrance is clear. Look up and down: can a swift swoop in and drop out without clipping anything?
• Mark the screw holes. Drill pilot holes into the wall. Use wall plugs if the surface is brick or render.
• Fix the box tightly. It should not wobble. Swifts are sensitive to movement.
• Add a thin layer of wood shavings or dry grass inside. Swifts do not bring nesting material; they need a soft base for eggs.
• Seal any gaps around the box with draught-proofing strip, but do not block the entrance.

If you have a brick wall, you can also use a built-in swift brick during renovations. These are designed to sit flush with the wall and look neat. But a surface-mounted box is fine for most homes.

Playing Swift Calls to Attract Prospecting Birds

Swifts are social. Young birds looking for their first nest site are drawn to the sounds of other swifts. You can exploit this by playing swift attraction calls near the box. These are recordings of swifts screaming in flight. Play them from a small speaker placed just below or beside the nest box.

Timing matters. Start in early May, when swifts return from Africa. Play the calls in the morning and late afternoon, for about 20 minutes at a time. Do not play them all day; that can confuse birds and annoy neighbours. Keep the volume moderate. The aim is to mimic a small colony, not a full-blown swift party. Continue until mid-July. If a pair takes up residence, stop playing calls. Once swifts breed, they return to the same site year after year. Even if no birds nest this season, prospecting swifts may remember your box for next year.

The Wetland Connection: Feeding Swifts from Your Pond

Swifts eat flying insects, and they need a lot of them. A single swift can catch thousands of insects a day. This is where wetland nature in your garden becomes vital. A wildlife pond, even a small one, produces clouds of midges, mayflies and caddisflies. These insects emerge from the water and drift upwards, exactly where swifts hunt. Adding a pond with native marginal plants such as water mint, marsh marigold and lesser spearwort boosts insect numbers. Avoid fish, which eat larvae. If you do not have space for a pond, a bog garden or a rain garden with damp-loving plants will help. Swifts also feed over marshes, wet meadows and canals. If you live near such habitats, your nest box is even more valuable.

Patience, Persistence and a Little Luck

Swifts do not always move in straight away. It can take two or three years. But the wait is worth it. The sight of a swift screaming past your eaves on a summer evening is a thrill. Keep the box clean and maintained. Check it from the ground each spring. If wasps or sparrows move in, gently clear the box in winter. Do not disturb active nests. With a well-placed box, a little sound, and a garden that hums with wetland insects, you are giving one of our most spectacular migrants a real home. And that is a fine thing to do for UK wildlife.