Pipistrelles are the UK's most common bat, but that's not to say that they're not under threat. Pipistrelles are commonly found roosting in the lofts of houses and in holes and hollows in tree trunks. Each bat weighs less than a 2p coin and has the ability to change from warm to cold blooded so as to stay at an ambient temperature.
The Pipistrelle bat is the most abundant and widespread bat species in the UK - but is thought to have undergone significant decline in numbers this century - 70% decline between 1978 and 1993 (National Bat Colony Survey). There are problems in estimating population trends due to the recent discovery that there are 3 distinct species of Pipistrelle Bat breeding in the UK. P. pipistrellus and P. pygmaeus are recorded from Sheffield, but not P. nathusii.
Locally the Pipistrelle is the commonest bat in Sheffield with a widespread distribution and apparently high population level across the City and the Coalfield Natural Area. Most breeding roosts can be found in occupied properties, usually domestic, and including 20th century houses - they are usually found in gable wall apex cavities, under soffits, between roof tiles and roof felt or in flat roof spaces. They usually roost at lower altitudes and the highest recorded roost in Sheffield is near Strines. Feeding sites occur where there are plenty of flying Chironomids (Mosquitoes and Midges) and where it is warm and sheltered - e.g. rivers, ponds, clearings and rides in woodlands, and gardens. Hibernation sites are usually deep in wall cavities of buildings where bats hibernate in ones or twos - not in large groups. Caves and mines are not usually used by this species.
The Pipistrelle bat is a BAP short list species and internationally is protected by the Bern convention (1979) and the EC Habitats and Species Directive 1992. National protection is provided by the Wildlife and Countryside Act 1981 and schedule 2 of the Conservation (Natural Habitats etc.) Regulations 1994. Locally the impact on bats can be limited by activities in accordance with PPG9 and via LA21 / BAP process.
As local population levels are relatively high it seems inappropriate to try to increase the population level without adequate research and information. This could, for example, have an adverse effect on the other locally rare bat species.
Upland Oak Woodland, Wet Woodland, Ancient Woodland, all other woodlands, Water Courses, Reservoirs and Ponds, Wetlands (particularly in woods and unimproved grasslands etc. for insect breeding sites).