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

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.