Bats can be commonly found in the UK.
As a protected species, you may need to carry out a bat survey should you find a bat on development land. As experienced ecologists, our range of ecology services can help you to establish the presence of bats, and take the appropriate steps to avoid damage to their habitat as well as ensure any development plans can go ahead legally. You will need a bat survey licence if there is a possibility of disturbing bats.
Read our Bat Survey Guidelines to discover what is involved in a bat survey, why you may need one, and how the process works.
We answer some of the most popular questions about bats below.
Why do bats sleep upside down?
Not all bats do. Some species will wedge themselves into small crevices on a building or in a tree. However, many species are free hanging. Their toes will automatically grip surfaces and are equipped with claws for better purchase (these are absent from its fingers).
Some bats will also eat upside down. We call areas where a bat does this ‘feeding perches’, which are not necessarily in the same place as its roosting spot during the day.
Where do bats live?
Bats live in roosts. Different species prefer to roost in different places. Some will utilise holes in trees, others prefer caves or underground tunnels. Several species will roost in buildings, with some preferring larger open spaces, such as in a loft, while others will wedge themselves into small crevices between roof tiles, or anywhere else they can find!
How many species of bat are there?
There are more than 1,400 species of bat worldwide, comprising around 20% of all known mammal species.
What bats are in the UK?
In the UK there are 18 different species. Of the UK species all but one breed here. The remaining species, the greater mouse-eared bat, is restricted to just one bat that has been hibernating in southern England since 2002.
Why not check out our interactive Bat Quiz? Put your knowledge to the test!
How large are bats?
The smallest UK species are the common pipistrelle and soprano pipistrelle. Pipistrelles have a body length of 35-45mm and a wingspan of around 200mm. The pipistrelles are exceptionally light, weighing around 5g (the same as an A4 sheet of paper).
The greater mouse-eared bat is technically the largest species in the UK, but the noctule tops the list for the more common species. The noctule is only slightly longer than the pipistrelles, measuring 37-48mm, but has a wingspan of 320-400mm. The noctule is also significantly heavier, weighing 18-40g.
It can be tricky to spot the difference between the species when in flight. However, when it is still light during a bat survey the larger species, including the noctule, serotine and Leisler’s bats, do stand out.
Are bats blind?
No! The bats in the UK have smaller eyes compared to some other species around the world, but they can see through them. However, they are much better at navigating and foraging using echolocation.
How do bats use ultrasound?
Echolocation is the process by which bats emit sound waves and listen for the returning echo. The frequency at which they ‘call’ varies between species, however, the soundwaves they emit are usually at too high a frequency for humans to hear.
Recording bat calls are an integral part of how ecological consultancies identify bats. Specific detectors are used capture the sound during bat surveys, and computer programs are later used to represent the calls visually.
When do bats hibernate?
Bats will generally hibernate from November onwards. There are still unanswered questions about where many bats go to hibernate. Bats may start feeding on warmer nights as early as March and will emerge fully over April.
What time do bats come out at night?
This varies between bats but also depends on other factors including the cover around their roost and the prevailing weather conditions. The first species to emerge will start leaving their roost anytime from sunset onwards, while others prefer to wait for the cover of darkness. Bats will usually return to their roost in the hours before sunrise.
What do bats eat?
All bat species in the UK feed on insects, including midges, moths, beetles and flies. Bats elsewhere in the world can have different diets, including fruit and flowering plants. There are even three species of vampire bats in Central and South America that subsist on blood!
How long do bats live?
The lifespan of a UK bat can vary a lot. The most common species, the pipistrelles, have an average lifespan of four to five years. The longest-lived species include Brandt’s bat, which can live up to 40 years, and the greater horseshoe, which can make it to 30.
Do bats carry rabies?
Some bats carry rabies viruses EBLV-1 and EBLV-2 but the disease is very rare in the UK. When spread, it is usually by the bite of an infected bat, but it can also be spread if the saliva of an infected bat gets into open wounds or mucous membrane. Therefore, you should avoid handling or approaching a bat.
What to do if you find a bat
The Bat Conservation Trust (BCT) provides a guide on what to do if you find a bat that may be grounded, exposed, or lost. It sets out how to assess the situation, how to contain the bat safely if it needs help, and provides details for the National Bat Helpline. An important point is that you should avoid handling the bat if possible; however, if you do need to touch it then wear thick gloves as there is a small risk of rabies transmission.
If you have found a bat during building works, there are additional processes you need to follow. Both bats and their roosting places are legally protected. Works should stop immediately, and you should consult an ecology consultant, who will be able to advise on the next steps. Please call us on 01865 893346 or contact us today if you require assistance.
How are bats protected?
The Wildlife and Countryside Act (1981) (as amended) makes it an offence to:
Intentionally kill, injure or take a bat;
Possess or control any live or dead specimen or anything derived from a bat;
Intentionally or recklessly damage, destroy or obstruct access to any structure or place used for shelter or protection by a bat; and
Intentionally or recklessly disturb a bat while it is occupying a structure or place which it uses for that purpose.
Additionally, The Conservation of Habitats and Species Regulations 2017 (as amended) make it an offence to:
Deliberately capture or kill a bat;
Deliberately disturb a bat;
Damage or destroy a breeding site or a resting place of a bat; and
Keep, transport, sell or exchange or offer for sale or exchange a live or dead bat or any part of a bat.
Some exceptions are allowed, providing the work is appropriately licensed. For example, bat survey licences are needed if bats might be disturbed during surveys, whether this is by torchlight, endoscopes, hand, mist net, acoustic lures or harp traps. Bat mitigation licences are needed if there is the potential for construction work to affect bats.
Why are bats protected?
Bat populations declined significantly over the 20th Century, with human activities driving declines in their foraging habitats, prey and roosting sites.
In addition to their intrinsic value, bats are considered a valuable biodiversity indicator. This means change in bat populations can reflect change in their underlying ecosystems. In other words, they act as a kind of health check on the wider natural environment.
There are encouraging signs from the past twenty years. Findings from the National Bat Monitoring Programme indicate the populations of the species monitored are stable or recovering.
What’s involved in a bat survey?
We start within an initial scoping survey, where we assess whether the habitats on-site are likely to be valuable for foraging or commuting bats or, in the case of trees and buildings, whether there is any evidence of use by bats or potential roosting features for them to use (i.e. holes in trees, gaps in tiles).
Then additional surveys are completed to determine if bats are present. This can entail walking transects through fields or woodland to record foraging and commuting bats or watching trees and buildings to record any bats entering and exiting. The exact methods and timings are set out in our bat survey guidelines.
Do bats carry rabies?
Some bats carry rabies viruses EBLV-1 and EBLV-2 but the disease is very rare in the UK. When spread, it is usually by the bite of an infected bat, but it can also be spread if the saliva of an infected bat gets into open wounds or mucous membrane. Therefore, you should avoid handling or approaching a bat.
Helpful Ecology Survey resources
Preliminary Ecological Appraisal Guide