Low frequency warbled qCF calls

All the following calls are emitted from within a maternity roost.

Common pipistrelle:

Serotine bat:

Pond bat:

All recordings are licensed under the following Creative Commons Attribution-NonCommercial-NoDerivs 4.0 license and in courtesy of Sarah Mahie. 
All sonograms are screenshots of the recordings imported in the ultrasound analysis software BatExplorer 2.2 (Elekon, Switzerland).