Soprano Pipistrelle

Soprano Pipistrelle © Sonia Reveley

The Soprano Pipistrelle (Pipistrellus pygmaeus) is one of UK’s two commonest species of bats; the other is the Common Pipistrelle. Both Pipistrelles are Britain’s smallest bat species. The Soprano Pipistrelle is widely distributed throughout the UK, except for Northern Scotland. It has a preference for riparian habitats, and can be found foraging along water bodies such as rivers, lakes, canals, and reservoirs. It will also hunt in woodlands (deciduous and mixed), but rarely on farmland. It was finally recognised as a separate species in the 1990’s after DNA studies.

The Soprano Pipistrelle is a small medium to dark brown bat, (paler brown when compared to a Common Pipistrelle), with a sandy to reddish brown tint. It has a short snout and a pale face usually pink in colour and weighs between 3 – 8 g (the weight of a two pence coin).

The calls of the Soprano Pipistrelle can be picked up on a heterodyne detector between 55 – 80 kHz. The deepest and clearest calls can be heard at the peak frequency of 55kHz. The calls emitted by the Soprano Pipistrelle are fast and repetitive; sounding like loud wet slaps and clicks.

On a sonogram, the shape of the Soprano Pipistrelle call is very distinctive, ending with a “hook” or “hockey stick.” (see sonogram below)

Soprano Pipistrelle sonogram. Recorded on a SM2 Bat detector and analysed using Sonobat

In the winter, Soprano Pipistrelles will hibernate in building crevices, trees or bat boxes. They tend to roost singly or in small groups. However in the summer, maternity colonies are formed, which can reach quite large numbers. Maternity roosts can be found behind wall claddings, hanging tiles, weather boardings, eave boardings, cavity walls, as well as tree holes and crevices and bat boxes.

Soprano Pipistrelles tend to emerge from their roost around 20 minutes after sunset, though they do occasionally come out before. Their flight pattern is fast, jerky and erratic. They prefer to forage along habitat edges i.e. hedgerows, water edges, approximately 2 – 10m above ground level, catching and eating their prey during flight. Their diet consists of small flies, midges, mayflies, and lacewings.