The Hour When the Countryside Changes Hands

There is a moment on a warm summer evening, somewhere between twenty and forty minutes after sunset, when the character of the countryside quietly changes. The swallows have gone up, the bees have settled, and the air above the hedge suddenly fills with small, fast, jinking shapes. Bats. They have been there all day, tucked into gaps you walk past without noticing, and now they are out on the night shift.

Britain has around eighteen resident bat species, depending on how you count the rare visitors, and every one of them is legally protected. That protection covers the animals themselves and the places they rest — including roosts you may not even know you have. Learning a little about their habits turns an ordinary dusk into something worth sitting still for, and it makes you a better neighbour to the wildlife already sharing your patch.

Where British Bats Spend the Day

Bats are not nest-builders. They are opportunists, squeezing into whatever offers warmth, shelter and a narrow entrance. Different species favour different addresses:

• Pipistrelles, our commonest bats, tuck into roof voids, behind hanging tiles, under soffits, in cavity walls and behind loosenened flashing. A gap the width of a thumb is enough.
• Brown long-eared bats prefer roomier lofts, often roosting along the ridge beam, and are notoriously hard to spot because they are quiet and well hidden.
• Lesser and greater horseshoes need large, stable, humid spaces — old stone barns, church roofs, cellars and mine workings, mostly in the west and along the Welsh borders.
• Noctules, barbastelles and others roost in trees, using woodpecker holes, splits in trunks and lifted bark.
• Daubenton's bats often roost under bridges over slow rivers, emerging low and fast over the water.
• Caves, tunnels, ice houses and mines are the hibernation sites that carry bats through the winter.

In summer, females gather in maternity roosts to raise a single pup each. Because bats return to the same sites year after year, a roost is a long-term commitment — which is why any roofing, loft conversion, tree felling or barn repair should be checked before work begins. If in doubt, a local bat group or your county wildlife trust can point you towards proper advice.

What They Eat, and How They Find It

Every British bat eats insects, and they eat a staggering number of them. A single pipistrelle can take around three thousand small flies and midges in a night, hunting by echolocation: bursts of ultrasound that bounce back off prey and landscape, painting a picture in sound. Most of those calls sit above the range of human hearing, though the ticking chirp of a noctule high overhead is sometimes just audible.

Their menus differ with their bodies. Pipistrelles snap up midges, small moths and flies in open air. Brown long-eared bats hover and glean moths and beetles straight off leaves, often carrying larger prey to a feeding perch to chew in peace. Daubenton's bats trawl the water surface with their feet and tail membrane for caddisflies and mayflies. Noctules fly fast and high, taking chafers and larger moths at a hundred metres or more.

Telling What You Are Watching

You do not need equipment to enjoy bats, but a little pattern recognition deepens the pleasure:

• Small, erratic, jinking flight a few metres up, around trees and gardens — almost certainly a pipistrelle.
• Large, straight, powerful flight high against the fading sky, often before full dark — a noctule.
• Low, level, direct flight just above a river or canal — Daubenton's.
• Slow, fluttering, close-to-foliage movement, later in the evening — a brown long-eared bat.
• Flickering flight very close to the ground or a hedgerow, with calls too faint to hear — likely a horseshoe.

A simple heterodyne bat detector, tuned between 20 and 55 kHz, will confirm much of this, and the change in rhythm when a bat closes in on prey — a rapid "feeding buzz" — is one of the loveliest sounds of a summer night.

Watching Them Humanely

The pleasure of a dusk vigil depends on disturbing as little as possible. Bats leaving a roost are vulnerable, and a badly placed torch or a curious cat can do real harm.

• Stand ten to fifteen metres back from a roost entrance, and never directly beneath it.
• Use a torch sparingly, with a red filter if you have one. Keep the beam low and short. Never shine light into a roost or loft hatch.
• Avoid ladders, drones and sudden noise at emergence time. Watching from a garden bench is plenty.
• Never handle a bat. If you find a grounded one, keep pets and children away, cover it loosely if needed and ring a licensed bat worker or wildlife rescue for advice.
• Keep cats indoors from dusk until dawn through the summer months.
• Check before any building or tree work — roosts are protected even when the bats are out feeding.

A Slower Evening, and a Friendlier Patch

Bat-watching is really a lesson in doing less. Arrive early, sit down, put the phone away and give it twenty unhurried minutes. The first bat often appears exactly where you stopped expecting one.

You can also make your corner of the countryside easier to live in. A small pond or even a sunken basin with a stone ramp draws in insects and, in time, Daubenton's bats. Night-scented plants such as evening primrose, honeysuckle, jasmine and tobacco flower feed moths, which feed bats. Leave rough grass, dead wood and native hedgerow alone where you can.

Lighting matters more than most people realise. Swap constant dusk-to-dawn lamps for motion sensors, choose warm white over harsh cool white, shield fittings so the beam points down, and keep light levels low. Skip insecticides, especially near water. If you hang a bat box, put it three to five metres up on a sheltered south or south-east wall, away from windows and exterior lights, and give it a season or two to be found.

Then simply keep the appointment. Same bench, same time, most evenings through June and July. Over a summer you will learn the exact minute the pipistrelles appear, which night the noctule returns, and how the whole hedge comes alive at the boundary between day and dark. It is slow living at its most rewarding — and it costs nothing but a little patience and a warm mug in your hands.