<p>Not particular to these devices, but perhaps consider:</p>
<ul>
<li>Was there lots of variation in the temperatures at which your 26 devices were located?</li>
<li>Was there variation in the length of time between the last charge to turning-on for the deployment?</li>
<li>Was there variation in the age/previous use of your devices?</li>
</ul>

CC BY-SA 4.0
2022-07-08T13:46:28.240Z
All great points, thank you! All but 4 were newly-bought devices and the 4 older ones (Audiomoth v1.1) had not been previously deployed even so, so for at least previous use, it was also the same. I'll have to look back and see if the v1.1 devices showed shorter deployment times. And because they all had not been previously deployed, there was no time between last charge. Temperature/rain varied somewhat as we were deploying them in a narrow north/south corridor (200km between most northern and most southern devices).
Carly Batist
CC BY-SA 4.0
2022-07-08T13:54:15.587Z
So are you saying that they were last charged by the manufacturer, and not by you? Batteries can lose some juice if they're just sitting on a shelf.
Chloe
CC BY-SA 4.0
2022-07-08T13:57:08.500Z
They weren't rechargeable batteries, they were lithium-ion (Energizer Ultimate Lithium).
Carly Batist
CC BY-SA 4.0
2022-07-08T13:58:19.757Z
Ah ok, silly me. Assuming they were fresh?
Chloe
CC BY-SA 4.0
2022-07-08T14:00:10.247Z
Yep had just bought them before fieldwork, so the oldest ones were still only ~4 months
Carly Batist
CC BY-SA 4.0
2022-07-08T13:43:16.623Z
2022-07-08T13:43:16.623Z
Chloe
<p>I deployed 26 Audiomoths in my last field season and am just starting to organize the data. I've noticed that there seems to be a LOT of variation in the amount of time each device recorded - the range is 9-16 days. This even though I used the same new batteries (Energizer Ultimate Lithium AAs), SD cards (SanDisk ExtremePro 128GB), and settings (48kHz sample rate, medium gain, bandpass filter 1-20kHz, recording 8am-5pm on 55sec on/5 sec off continuous schedule).</p>
<p>I know there can obviously be slight differences in the actual hardware pieces, batteries, and what not, but a week's worth of variation seems like too much to explain just with that... Has anyone else run into this level of recording time variation across recorders? Anyone have any ideas about why this variation exists? Thanks!</p>

CC BY-SA 4.0
2022-07-08T17:16:49.130Z
Did you check the batteries with a battery tester before deployment to ensure that they were actually as full as you thought they were?
dtsavage
CC BY-SA 4.0
2022-07-13T13:38:52.627Z
Following this. We've had issues with our AudioMoths doing this as well. It's happened both with duty-cycled and continuous recordings...
Jack Butler
CC BY-SA 4.0
2022-07-13T13:40:01.403Z
No David I hadn't. Since they were like right out of the package Energizer Ult Lithiums I didn't think it necessary...
Carly Batist
<recording><terrestrial><audiomoth><deployment>
Differences in length of time Audiomoths record with same batteries/SD cards/settings?
# Differences in length of time Audiomoths record with same batteries/SD cards/settings?

(Asked by: username_0 on 2022-07-08)

I deployed 26 Audiomoths in my last field season and am just starting to organize the data. I've noticed that there seems to be a LOT of variation in the amount of time each device recorded - the range is 9-16 days. This even though I used the same new batteries (Energizer Ultimate Lithium AAs), SD cards (SanDisk ExtremePro 128GB), and settings (48kHz sample rate, medium gain, bandpass filter 1-20kHz, recording 8am-5pm on 55sec on/5 sec off continuous schedule).

I know there can obviously be slight differences in the actual hardware pieces, batteries, and what not, but a week's worth of variation seems like too much to explain just with that... Has anyone else run into this level of recording time variation across recorders? Anyone have any ideas about why this variation exists? Thanks!

**Tags:** recording, terrestrial, audiomoth, deployment

> **Comments:**
> **username_1**: Did you check the batteries with a battery tester before deployment to ensure that they were actually as full as you thought they were?  
> **username_2**: Following this. We've had issues with our AudioMoths doing this as well. It's happened both with duty-cycled and continuous recordings...  
> **username_0**: No David I hadn't. Since they were like right out of the package Energizer Ult Lithiums I didn't think it necessary...  

---

## 1 answers

### Answer by username_3 on 2022-07-08. Score: 5

Not particular to these devices, but perhaps consider:

* Was there lots of variation in the temperatures at which your 26 devices were located?
* Was there variation in the length of time between the last charge to turning-on for the deployment?
* Was there variation in the age/previous use of your devices?

> **Comments:**
> **username_0**: All great points, thank you! All but 4 were newly-bought devices and the 4 older ones (Audiomoth v1.1) had not been previously deployed even so, so for at least previous use, it was also the same. I'll have to look back and see if the v1.1 devices showed shorter deployment times. And because they all had not been previously deployed, there was no time between last charge. Temperature/rain varied somewhat as we were deploying them in a narrow north/south corridor (200km between most northern and most southern devices).  
> **username_3**: So are you saying that they were last charged by the manufacturer, and not by you? Batteries can lose some juice if they're just sitting on a shelf.  
> **username_0**: They weren't rechargeable batteries, they were lithium-ion (Energizer Ultimate Lithium).  
> **username_3**: Ah ok, silly me. Assuming they were fresh?  
> **username_0**: Yep had just bought them before fieldwork, so the oldest ones were still only ~4 months  

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