There is a particular hush that falls over a British garden or woodland edge just as the light begins to drain from the sky. The blackbirds have finished their evensong, the midges gather in soft columns, and then — if you are still and patient — the first bat flickers past. It is one of the most accessible yet overlooked wildlife spectacles we have, and with a modest bat detector in hand, you can turn a warm evening into a genuine survey of your local hedgerows and trees.

The Twilight Shift: When and Where to Watch

Bats are creatures of habit, and their evening emergence follows a predictable rhythm. In Britain, the best months run from April through to October, with peak activity in June, July and August when females are raising pups. You do not need to stay out until midnight. Most species emerge in the first hour after sunset, so aim to be in position about twenty minutes before the sun goes down.

Choose a mild, still evening with little wind and no rain. Temperatures above 10°C are ideal. The best spots are near water — a pond, a slow river or a canal — because insects swarm there. Woodland rides, mature hedgerows and the edges of gardens with plenty of trees are also reliable. Stand quietly, avoid torchlight, and keep conversation to a whisper. Bats are not easily scared by a quiet human, but they will avoid a noisy, moving observer.

Your Bat Detector: A Simple Guide

Most bat calls are too high-pitched for human ears, which is where a bat detector comes in. For beginners, a heterodyne detector is the most practical choice. It converts ultrasonic calls into audible clicks and smacks in real time. You simply tune the dial to a frequency and listen through headphones.

• 45 kHz — the starting point for common pipistrelles, our most widespread bat.
• 55 kHz — the setting for soprano pipistrelles, a separate species that often prefers water and woodland edges.
• 20 kHz — the realm of the noctule, one of our largest bats, which often emerges early and flies high.

Scan slowly. Turn the dial a little at a time and listen for the sudden burst of a hunting bat. Headphones are essential — they keep your hands free and stop the sound from disturbing others.

Reading the Calls: Pipistrelle, Soprano and Noctule

With a little practice, you can identify the three most common bats by sound alone. The common pipistrelle at 45 kHz produces a rapid series of wet slaps, like a small stone skipped across a pond. It is the classic garden bat, often circling a single tree or hedgerow at head height.

The soprano pipistrelle is slightly smaller and its call is higher and thinner. At 55 kHz you will hear a faster, more rhythmic ticking, almost like a tiny metronome. It is especially fond of feeding over water and along woodland streams.

The noctule is a different beast altogether. Tune to 20 kHz and you may hear a loud, harsh chip-chop — sometimes audible to young ears without a detector at all. Noctules fly high and fast, often before sunset, and their calls carry a muscular, almost mechanical quality. If you hear a bat but cannot find a frequency, slowly sweep the dial until the sound snaps into focus.

Gardening and Foraging for Bats

You can make your garden a better place for bats without any special equipment. Plant night-scented flowers such as evening primrose, honeysuckle, jasmine and nicotiana. These attract moths, which are the main prey for most British bats. Leave a wild corner with long grass, a log pile and a small pond if you have space. Avoid pesticides and herbicides — a healthy insect population is the single most important thing you can provide.

Hedgerows are vital corridors. Native species like hawthorn, blackthorn, hazel and field maple support a huge range of insects. If you are out foraging while you wait for the bats, you can gather elderflowers in late May and June, wild garlic in spring, or blackberries in late summer. Just remember to keep your foraging close to your watching spot, and never strip a hedge bare — leave plenty for the wildlife that depends on it.

Respecting Bats and Staying Safe

All British bats and their roosts are protected by law. You must never handle a bat unless you are trained and licensed. If you find a grounded or injured bat, contact a local bat conservation group for advice. Use a red-filtered torch if you need light — white light disturbs them far more. Keep noise to a minimum, and do not use a bat detector right outside a known roost, as this can cause stress.

Finally, enjoy the quiet. Watching bats is not about ticking off species; it is about tuning into a hidden layer of the British countryside that carries on while most of us are indoors. Stand still, breathe slowly, and let the dusk deliver its small, winged surprises.