The common pipistrelle is one of the most common British bats.
They are the species people are most likely to spot in their gardens, with each one eating thousands of insects a night.
The common and soprano pipistrelle, also found in the UK, were only identified as separate species in the 1990s, according to the Bat Conservation Trust.
They look similar and the easiest way to tell them apart is from the frequency of their echolocation calls.
Common pipistrelles feed in habitats including woods, hedges, grassland, farms, suburban and urban areas.
They usually come out about 20 minutes after sunset and fly 2m to 10m (6.5ft to 33ft) above ground searching for food, which they eat on the wing.
Summer roosts of common pipistrelles are often found in crevices around the outside of newer buildings.
They can be found behind hanging tiles, between roofing felt and roof tiles or in cavity walls.