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As the only flying mammal, bats are fascinating creatures who sleep upside down and use echolocation to navigate. There are 1,400 species of bats in the world – and more are still being discovered.

A Daubenton’s bat with short ears, brown fur, and a pale grey underside stretches grey wings in flight. Known as the 'water bat', Daubenton’s bats fly close to water to fish insects from its surface

Bat facts

Scientific name: Chiroptera

Diet: Small flying insects

Predators: Birds of prey or domestic cats

Size: Pipistrelle bats measure 3-5cm with a wingspan of 19-25cm. The greater horseshoe bat and the noctule bat have a wingspan up to 38cm

Weight: 3-9g. Larger species can weigh up to 40g

Lifespan: 4-5 years

Creatures of night

Britain is home to 18 different species of bat – from the common pipistrelle, a tiny bat weighing less than a two-pence coin, to the noctule with a wingspan of up to 40cm.

One of the species you’re most likely to see on our network is the Daubenton’s bat. Also known as the ‘water bat’, they’re regular nightly visitors to our canals and major consumers of flying insects.

Despite common misconceptions, bats aren’t blind. They can actually see very well. However, they use their ears more than their eyes at night. Bats shout as they fly, using the returning echo to detect what’s ahead – known as echolocation. These sounds are so high in frequency that we cannot hear them without bat detectors.

Bats and our canals

Many of our 200-year-old tunnels, bridges, buildings, and aqueducts are home to bats. This means we have to take care when working with any of our heritage structures or trees in case bats, which are protected by law, are present.

Our canals and rivers provide important passages for bats, bringing nature into our towns, cities, and intensively farmed landscapes. These corridors bypass the perils of roads and provide safe links in an increasingly fragmented countryside.

How to identify a bat

Bat species are a variety of shapes and sizes. In the UK, they range from black and grey to reddish brown. Generally speaking, they have short snouts, large ears, fur-covered torsos, and skeletal wings.

What bats will you find in the UK?

Take a walk along a canal at dusk and you might spot one of 18 bat species living in the UK.

  • Alcathoe's bat

    Known to live in Yorkshire and the south of England, Alcathoe's bat has reddish-brown fur and short brown ears. It measures up to 4cm with a 20cm wingspan.

  • Barbastelle bat

    The barbastelle bat is a rare creature, found in ancient woodlands in the south. The barbastelle has an upturned nose with small eyes and wide ears joined at the base. It measures 4.5cm with a 27cm wingspan.

  • Brown long-eared bat

    So-called for its long ears (measuring 2.8cm), the long-eared bat uses its ears to navigate and find food. It has light brown fur and a pale underside. Long-eared bats have a body of around 4.5cm and a wingspan of up to 25cm.

  • Daubenton’s bat

    Known as the ‘water bat’, Daubenton’s bat often roosts in trees. Daubenton’s bats have short ears with fluffy brown fur, a pale grey underside, and a pink face. Distinctive by its large feet, this bat measures around 4.5cm with a 25cm wingspan. You might spot these bats flying low over the water, like a hovercraft.

  • Grey long-eared bat

    Similar to the brown long-eared bat, the grey long-eared bat is a rarer species only found in the south of England. Grey long-eared bats have darker fur and measure 4.5cm with a 25cm wingspan.

  • Horseshoe bats

    Found in the southwest of England and Wales, lesser and greater horseshoe bat populations are declining. In summer, they roost in roof spaces and hide in underground sites, like caves, in winter. Greater horseshoes measure 6.4cm with a 34cm wingspan and a distinctively fleshy nose (shaped like a horseshoe).

  • Noctule

    Noctule bats roost in trees mainly, forage widely, and are one of the largest bats found in the UK. It has golden fur with a darker face, measuring 7.5cm with a 36cm wingspan.

  • Pipistrelle

    There are three kinds of the smallest bats in the UK: common, soprano, and Nathusius’ pipistrelle bats. Known for roosting in houses, trees, and bat boxes, pipistrelles forage everywhere and live in colonies of over 1,000. They’re black and brown, measuring only 3.5cm with a 22cm wingspan.

  • Serotine

    Found in the south, serotine bats return to the same roost every year. They have dark brown fur and a brown or black face. These bats measure 6.4cm with a 36cm wingspan.

  • Whiskered and Brandt’s bat

    Typically found in woodlands and by the water, these two species are very similar with more fur around their eyes and face than other bats. They measure 4cm with a 24cm wingspan.

What do bats eat?

Bats venture out at dusk to hunt prey. They usually eat flying insects, like moths, mosquitoes, midges, flies, and other nocturnal insects. They use a highly sophisticated form of radar (echolocation) to detect their prey. The high-pitch squeak echoes off the object and tells the bat its size, location, velocity, and even texture.

Pipistrelle bats can eat around 3,000 insects a night, roughly a third of their weight. Daubenton’s bats typically feed close to their roosts but have been known to travel as far as 10km along canals. They take their prey from close to the water or directly from the water surface.

When food is scarce (for instance, in a wet, cold summer), bats can go into semi-hibernation, known as a ‘torpor’. In this state, they can conserve energy until temperatures rise.

Where do bats live?

With climate change pushing warmer temperatures, some bats are moving further up the country to the north. If winter temperatures exceed seven degrees, bats might wake up from hibernation to feed before going back to sleep.

Bats live in a variety of habitats. They like to make their homes with easy access to feeding sites, in pollution-free areas. From bridge cavities to woodlands, there are plenty of spaces to spot them along our canals.

Tips to spot bats

Elusive creatures of the night, bats are often glimpsed as a small flitter in the corner of our eyes. You’ll see them around dusk as they venture out to hunt their insect prey.

What's the best time of year to spot a bat?

Bats are most commonly seen in the summer when they’ve woken from their winter hibernation.

The best time of year to see a bat is between May and September. You’re most likely to spot them flying in the first half hour after sunset.

It’s important not to disturb a hibernating bat. Waking up uses vital energy reserves.

Threats to bats

Construction and development work that results in habitat loss remains the biggest threat to bats. In the days when Britain was covered in trees, bats often roosted in hollowed-out tree trunks or caves. However, now that so much deforestation has taken place, bats have been forced to seek alternative roosts.

Other species to look out for

Family nature guide 2019

Download your free nature guide

Identify footprints and read fascinating facts about the creatures who make their homes along our canals and rivers

Last Edited: 14 June 2024

photo of a location on the canals
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