- Lifespan
- 4–5 years in the wild, occasionally up to 20+ years in captivity
- Size & Weight
- 37–43 mm body length, wingspan 24–26 cm; 7–12 g
- Habitat
- Woodland, parkland, hedgerows, and buildings with access to open foraging areas; roosts in trees, caves, and attics.
- UK Distribution
- Found throughout England, Wales, and Scotland; year-round resident with no significant migration, though some local movements occur between summer and winter roosts.
- Diet
- Small flying insects including flies, mosquitoes, midges, and small moths caught in flight or gleaned from vegetation.
- Prey
- Diptera (flies), Lepidoptera (moths and butterflies), Hymenoptera (wasps and bees), small insects up to 15 mm
- Predators
- Tawny owls, sparrowhawks, and occasionally domestic cats; also vulnerable to roost disturbance and predation by rats in buildings
- Mating Season
- August to October, with sperm stored until spring
- Breeding
- Single litter per year of 1–2 pups born May–July; gestation approximately 7–8 weeks; pups weaned at 6–8 weeks old
- Behaviour
- Highly aerial hunter, characteristically flying slowly and deliberately with frequent hovering; highly social, roosting in colonies of up to 100+ individuals. Exceptional hearing allows detection of insect wing-beats; enters torpor during winter but does not truly hibernate.