Belongs to: mammals

Common pipistrelle Pipistrellus pipistrellus

massive decline

Best time to see: May to end Sep

Key facts

The smallest European bat, typically weighing 6 or 7g, and also the most widespread in Essex

Often roost and nest in the roofspace of houses and have declined because of toxic timber treatments and better sealing

Ultrasonic bat detectors have revealed two closely related species, one calling at 45kHz and one (soprano) at 55kHz


Brown or reddish brown fur with small triangular ears

Usually fly at or just above head height, zigzagging from side to side in search of prey

Feed on small flying insects like midges, using echolocation to locate and home in on their prey


Roost in the roofspace of houses and in holes in old trees and can often be seen leaving at dusk to hunt for food

Females have one litter a year in summer, joining nursery colonies of up to 1,000

Hibernate from autumn to spring, hanging in clusters sometimes numbering 1000s of individuals

  • photo

© Geoff Pyman