@Alex Rogers So I could use a Li-Ion pack at 7.2V through the same battery connection as the 3 AA cells. I may well adapt one with a suitable connector and see how that works. That would be great.

I do add caveats about the box being tight in my description. I have not found it to be too small but there is the risk of releasing the SD card (Yes I have done this) and the switch can be tight. I don't push them into the boxes so don't suffer from breakage. My thoughts are to move up a couple of sizes (to the 0.2l box) and use a foam insert to hold the audiomoth. This will also help to reduce mechanical noise on deployment.

What would be really nice is to have a power connector so we can use whichever power source we like. What are the functional limits for power on AM 1.1? - I'd like to try a solar -> Li Ion power source for long term remote monitoring.

@robwat It will seep with very heavy rain. But generally a shower is extremely intense, whereas a box on a tree will be far less exposed.

Please note these boxes as they come are not waterproof. I cast a seal with silicone - I am sure a conventional bath sealant would work as well as the mould making rubber I used.

I used the smallest box from Really Useful Products http://www.reallyusefulproducts.co.uk/uk/html/onlineshop/rub/b00_07litre.php in recycled black and a normal hot glue gun to attach the cloth. The trick is to ensure you get a really good bead of glue adhering to the plastic, then place the cloth over it and use the tip of the hot gun to push it into the glue. Not the best method and a bit tricky but it worked. I tried other adhesives (cyanoacrylate) but it didn't adhere well. I haven't tried some other plastic cements.

Thanks for this. I will try some larger cards. I have been sticking to 32 Gb with a duty cycle of 15s record, 30s sleep for 4/5 nights recording about 5 hours a night.

I've been trying batdetect and also BatClassify. I have some success with Batclassify, running at 384 kHz, 15 second file length. It does assign Ppyg social calls to NSL ( and has no Pnat) model. Batdetect runs faster but I haven't had much of a chance to get into the data. If I find the time I'll compare the two. I did find that BatDetect (anecdata alert) was not great at picking out all the calls from a file and was very prone to false positives. For what I am doing at the moment I take the spreadsheet of the 2500 or so file results from batclassify and rank them by score for each species in turn. I can then manually examine files down to a cutoff value (species dependent) to see if they are correct. Typically anything over .8 is definite for pips but you are not sure if there is something else in there, and I had some very faint echolocation with loud social calls that flagged up as NSL. For a moment I thought there was a Leislers in Scotland but more careful examination showed it to be a ppyg social call. Batdetect takes an hour or so to run on 2500 files on my not very high spec laptop and requires some python skills. Batclassify takes about 6 hours (ie overnight) for each directory of about that size.

Superb. I was procrastinating another task by starting to browse the Github code. I'm sure there is plenty of scope for enhancement.

I've been trying this. I can happily set a mounted drive by setting it to "E:\\Path/to/my/data/" and it then runs fine. I have fettled it to run under Python3. The quality of the output is variable. The audiomoths have periodic noise that is interpreted as a lot of calls. Depending on the species you are looking at, you may want to post-process the output and reject assigned calls that are too close together. My thinking is that a new set of models need to be developed for the AudioMoth, or the data needs some pre-cleaning to denoise it.

I should have some time to return to this after the weekend. I now have some recordings in a much quieter place so will try to run those. Depending on how you are running your script, you may find that the drives are mounted under /f/ instead of F:.

Like this? http://www.pauzuolis-rc.com/rc-shop/building-materials/mylar-film/mylar-film-3-mk It would be easy for me to swap out the acoustic cloth for the mylar on my boxes.

"I have tried making some bat recordings using a film of 3 micron aluminised Mylar over the microphone port " - does any one else read that as 'I put it in a crisp packet'? :)

Here are a couple of mine. They are sufficiently waterproof to be out in the rain. And a more distant shot

That's interesting. I got an horrendous error rate with the files I was using but perhaps they had more noise than expected. (under a road bridge over a river in the rain). I've been discussing it with the authors.

Also keen to try one. I think I will only need a tiny amount for my needs. Please let me know if you would be willing to sell one on

I'm planning on using the 0.07L Really Useful Box. The only downside is that the lid is not watertight. I do have a supply of silicone moulding rubber which I will use to cast some seals in the box lids. I'm keen to get hold of some of those stickers to seal over the microphone hole I will have to make. Anyone want to do a trade or is willing to sell me a small number?