| Bat partnership
Identifying UK bats
To identify bats you can use a range of information from the time of night they emerge, what they look like, their flying behavior and their calls. To listen to their call you need to use a bat detector.
We will aim to provide you with information on how you can use our bat detectors and your observation to identify the bats you see. We have also included some copies of the Field Studies Councils Guide to British Bats within our packs for you to borrow.
Calls can be variable, they can be affected by their surroundings, in different settings they can sound very different.
But don’t worry, some of our bat detectors also record the sounds they make – we can analyse these in more detail to confirm your identification. Give us some notes on their flight path, the habitat you are in, and when you saw them, was this close to sunset or afterwards? Give us a description of the site, an address or 6-figure grid reference and we can add the records to national databases where your records can help protect bats within the UK.
Bats
There are about 1,400 species of bat worldwide. The largest bats, the flying foxes have wingspans of up to 2 meters, the smallest weigh only 2 grams. Bats are mammals and share many features with us and other mammals we are familiar with.
British bats
In the UK we have 18 species of bats that are known to be breeding here. Bats eat a range of food from fruit, nectar, pollen, amphibians and fish, but all UK species only eat insects.
Pipistrelle species are amongst are our most common species.
Common pipistrelle
A very common species across the UK. They are often found flying around woodland, hedgerows and farmland. They can also be found in rural and urban settings and might be seen flying around your garden. They tend to emerge 15-20 minutes after sunset. They have an erratic flight path – circling 2-10m above the ground, around treetops and swooping through the air catching their prey.
Using our bat detectors you can also listen to their calls. They call between 45 to 70kHz, these sounds are loudest around 45kHz. You can tune the detector up and down the frequency range listening to where it is loudest. The call is described as a “wet slapping” sound. These slaps are pretty regular and 6-8 times per second. If you record their call using our bat detectors and send it to us using our forum we can analyse the “shape” of their call, their sonogram, and confirm any identification.
Soprano pipistrelle
Another common bat in the UK. They emerge around the same time as the larger common pipistrelle. Their flight pattern is also similar.
Using our bat detectors you can hear the calls between 55kHz to 80kHz. The sound is similar to the common pipistrelle but should be loudest around 55kHz.
Nathusius’ pipistrelle
This species is often found foraging near rivers, canals and lakes. Their flight is more rapid than the other pipistrelle species and they are also less manoeuvrable.
Their calls can be heard at a lower frequency than the other pipistrelles. The calls can be heard between 36 to 40KHZ and should be loudest around 38kHz.
Daubenton’s bat
Daubenton’s bat is also known as the water bat. They can often be seen 30 minutes to 90 minutes after dusk. They can often been seen flying low, in tight figures of eight, over water trawling for insects with their out-stretched feet before resting for short spells in trees. They have a lighter underbelly.
Their call can be heard between 35 to 85kHz and are loudest around 45-50kHz. Their calls come in bursts, to prevent themselves from hitting the water they send out rapid calls, these are often described as sounding like a machine gun.
Natterer’s bat
Natterer’s bats emerge about an hour after sunset. They have a slow to medium flight and can be seen flying around treetops. They often take prey directly from leaves. They can be found over water but fly less close to the surface than Daubenton’s bats. They are widespread in Gloucestershire.
Their call can be heard between 35 to 80kHz and is loudest around 50kHz.
Brandt’s bat
They emerge around 30 minutes after sunset. They fly around treetops and can often been seen in woodlands and can be seen picking their prey off plants and leaves.
Their call can be heard between 33 to 89kHz and are loudest around 45kHz. They can sometimes be mistaken for pipistrelles but have a wider frequency range.
Whiskered bat
They will begin to emerge around 30 minutes after sunset. They fly around treetops and occasionally swooping downwards and gliding around the canopy. They tend to fly regular flight paths over hedgerows and woodland edges. They have a two-tone fur.
Their calls can be heard between 32 to 89kHz and are loudest around 45kHz.
Bechstein’s bat
This is one of our rarest species. It is found, almost exclusively, in woodlands. They can be seen flying high above the canopy and sometimes nearer the ground.
Their call is very quiet but is loudest around 50kHz and sounds like a “tik”.
Noctule
Noctules are larger bats that feed on midges, beetles and moths. They can often been seen flying in the open in a straight flight path, they are one of our fastest bats. When feeding they use repeated steep dives to catch their prey. They can be sometimes been seen just before dusk and can be one of the first species to emerge.
Their call can be heard from 20-45kHz and is loudest around 25kHz. Their call is described as a repeated “chip-chop”.
Leisler’s bat
Leisler’s bats emerge around sunset. They can be seen flying in the open and around treetops, they then dive down for food. It is probably a rare species within Gloucestershire.
Their calls range from 15 to 45kHz and are loudest around 25kHz. The call is quite similar to the “chip-chop” call of the noctule bat.
Serotine
This is one of our largest species. They often take larger insects and can be seen flying around munching on their prey, sometimes they will take their meal to a feeding perch. They fly around tree-tops.
Their call ranges from 15 to 65kHz and is loudest around 25kHz, they sound like an irregular hand clap. They have also been called the “funky bat” as you can sometimes hear a syncopation in their call, they appear to miss a beat.
Barbastrelle
These bats are fast, agile fliers and often forage in open areas. They have been rarely recorded in Gloucestershire.
Their calls are heard around 32kHz and sound like short, hard smacks.
Alcathoe bat
These are usually found in old-growth deciduous forest, often near water. They forage high within the canopy. They have not been recorded in Gloucestershire.
Brown long-eared
Prey can be eaten in flight or on a perch. Their flight includes steep dives and short glides. They can be found in woodlands. A widespread and common species across Gloucestershire.
They echolocate between 25-50kHz and these are loudest around 35kHz. They are described as sounding like a Geiger counter with quiet series of clicks.
Grey long-eared bat
They can be found foraging in open spaces and catch their prey on the wing.
Their calls, like the brown long-eared bat, are very quiet and range between 29 to 63kHz.
Greater horseshoe bat
Greater horseshoe bats emerge about 30 minutes after sunset. They feed on insects in flight, but can sometimes been seen on the ground feeding. They usually fly quite low to the ground, sometimes they feed from a perch.
Their call is pretty complicated and sounds usual. It is heard around 82kHz.
Lesser horseshoe bat
They emerge about 30 minutes after sunset. They can be seen flying low over the ground hunting for their prey.
They also have a complicated call made of up of series of warbles, these can be heard around 110kHz.
We also have a range of guides in our bat detector packs to help you and your group identify bats.
For more information on UK bats visit the Bat Conservation Trust website. They also have audio recordings of the different species to help you get used to their calls.
UK Bats – Types of bats – Bat Conservation Trust
Gloucestershire bat group has lots of information on local bats and runs lots of events and activities in the area.
Gloucestershire Bat Group (glosbats.org.uk)
Gloucestershire bat group has a great guide to bats within the county.
Bats in Gloucestershire – Gloucestershire Bat Group (glosbats.org.uk)