Deployment on 100 sites in 2025 – Feedback
Last year, we deployed 100 AudioMoth dev recorders in France main land to record birds and bats in different public forest. Here is a feedback on how it went.
We used AudioMoth dev recorders in their dev cases with 3 Ansmann NiMH 10000 mAh D cells batteries and one SanDisk Extreme 512GB. They were set facing North at 1.5m on a wooden pole narrower than the recorder case. The sites were all enclosed forest plot to reduce theft.
The recorders were set with a duty cycle of 1/15min day and night. From sunrise to sunset, the sampling rate was at 44kHz and was then set to 250kHz during the night. This automatic switch was possible thanks to a custom firmware (Thanks again Alex). This switch was precise thanks to the location given by the AudioMoth chime app upon installation and its tracking of day length variation during the year.
The installation phase took two…
Hi Simon, Thanks for the really useful feedback. The SanDisk Extreme 512GB cards seem to be very reliable but have a relatively high energy consumption. See the comparison here: https://github.com/OpenAcousticDevices/Application-Notes/blob/master/A_Comparison_of_SD_Card_Energy_Consumption/A_Comparison_of_SD_Card_Energy_Consumption.pdf
The most up to date version of the firmware addresses some of the issue of the large SanDisk Extreme cards not sleeping, but not fully as they continue to consume energy for about 100ms after each SD card write.
The Kingston Canvas Select Plus have very low energy consumption and it would be great to do a back-to-back comparison on reliability and energy. With AudioMoth Dev it is also possible to switch between the internal and external microphones under firmware control so that might be something to consider also for next time if you want to try out external microphones for birds, and switch to internal for bats.
The updated firmware also now allows you to require acoustic chime each time the switch is moved to CUSTOM, and to also require a smartphone location. This might make it easier for users as every deployment will then require the chime (with location) on deployment. This also has the advantage that you get a very accurate GPS location in all the WAV files.
It would also be feasible to automate some of the configuration with web app that injests a list of locations in CSV or TXT and then sets the locations automatically.
The solar panel deployments look really interesting. Are these using the AdaFruit panels and controllers?
Alex