Date of recording: 2025-09-16          Recorded by: Saskia Verberne          Audio file: 1040664          Photo by: Saskia Verberne

Type C.d (male advertisement) social calls of a common noctule accompanied by a few type D contact calls.

Date of recording: 2025-08-16          Recorded by: Sarah Mahie          Audio file: 1029576

These social calls of the common noctule, the first of 2025, were recorded in a forrest:

Date of recording: 2025-05-12          Recorded by: Sarah Mahie          Audio file: 997499, 997503 (Batlogger M), 997505, 997506 (Echo Meter Touch 2)

Date of recording: 2025-06-19          Recorded by: Douwe van der Wijk          Audio file: 1007687 

Recorded in a forrest. The bats were seen flying above a small open patch between the trees and emitted type C socials calls only. Most identifyable common noctule echolocation calls are present in recording 1009263 (peak frequency lower than 20 kHz).

Date of recording: 2025-06-24          Recorded by: Sarah Mahie, Boaz van Die          1009258, 1009261, 1009263, 1009268, 1009269, 1009271 (Batlogger), 1009277, 1009280, 1009281, 1009391, 1009395, 1009396, 1009397, (Echo Meter)

Date of recording: 2025-06-19          Audio file: 1136555, 1136567, 1136568

The first snippit contains a bit of noise from the bicycle, but social calls from the common noctules can still be seen. The social calls in the two snippits after were recorded an hour later at the same location.

Date of recording: 2025-05-24, 2025-05-25          Recorded by: Sander Boersma          Audio file: 1137228, 1137232

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). 

Bibliography:

- Jon Russ (2021). Bat Calls of Britain and Europe: a Guide to Species Identification. Pelagic Publishing. 

- Neil Middleton, Andrew Froud and Keith French (2022). Social Calls of the Bats of Britain and Ireland (second edition). Pelagic Publishing.