Mobile batting (1 Viewer)

Hi, this is my first post at the birdforum. For my birding, I have the Canon SX50 and am happy with it (some great threads on the SX50 at this forum, by the way ). Lately I took my old DSLR out for a walk, but birding with a weight of 2.5kg around your neck is no fun.

My "next" hobby may well be bats, as I see them circling around in the park. But what would be the ideal equipment for identifying these bats? Heterodyne or FD bat detectors weigh only ~200g, but can fail to identify a bat. Is anybody here who is using a tablet-based solution, like the BAT miniMIC or Pettersson's M500?

A heterodyne detector might be "good enough" for a beginner, but I hesitate to buy one. Why waste $200+ if the "perfect" solution is a miniMIC or M500?

I think it depends on how you want to go about your hobby..
The traditional detectors ( I have an FD one), you go into the field, use your ears, and skill to identify bats.. Some you have to record, and analyse later.
These bat detectors are quite well designed for night work, with one handed operation, thumb dials etc., 1 cable to a small sound recorder in your pocket.

The new mics that attach to laptops/tablets, have everything available instantly including sonograms on the tablet by the look of it.

The downsides of the tablet/mic set I can see are that:
1. you don’t necessarily want to be staring at a bright LED screen in the middle of the night,
2. it’s another battery to worry about keeping charged (you don’t tend to have spare tablet batteries in your pocket),
3. it would be quite impractical to be fiddling on your tablet touchscreen whilst holding the mic, and wearing gloves, or insect repellent.
4. Tablet, mic, torch, is starting to become a bit of a juggling act
5. I often use my FD detector and sound recorder left hidden overnight in a lockable box remotely recording. I’m not sure you would have this option with a tablet/mic set up. Would tablet battery life be able to handle the workload? Do the Mics have their own battery supply?

I’m all in favour of new technology, but can’t see me performing my surveys or going bat detecting with these new mics. However, if you are out camping, or in the garden, they could be ideal. Bet they would be pretty good for "car-based" surveys too, for the passenger that is!

Probably worth noting that I don’t think you’ll be able to identify all species, even with the latest mics + tablet. Some species you need to see the bat, or leave as an either/or.

I haven’t used the latest mics, so it would be good if someone with experience of them offers their opinion.

Hope this helps, and would be good to hear others' opinions
Peter

Many thanks for the reply, Peter. A handheld detector with heterodyne and FD abilities must be an excellent tool in the field, in particular for someone with a knowledge of the various bat calls. For a beginner like me even a cheap model would be useful, offering vast opportunities to learn a lot and identify the most common species. But the moment will come, rather sooner than later, when I am getting more ambitious and try to identify the rare, shy and/or quiet bats. It has happened before, with the birds. I want to be able to tell a short-toed from a common treecreeper. A desire shared by most visitors of this forum, I guess.

So I am unsure what works best for me. A high-class detector like the Batlogger is too expensive. A mid-range model like the Ciel micro trio may be an idea (and probably still useful in any later mic-solution), but unable to catch all the bats. The idea to start with a tablet-based mic right from the start remains tempting. At least eight bat species are regular guests in our local riverside park, which is just two kilometers away from my home, and 13 species in the whole city. Wouldn't it be a safe bet that I'd eventually catch all of them, just by taking a regular night walk along the river, my GPS-tracking Asus tablet in the backpack and a microphone like the Pettersson M500 attached to the shoulder? A kind of "walking transect".

The five "downsides" which you mention are real, and I don't want to stare at a tablet screen in the dark park, studying sonograms. If possible, I'd just take this daily riverside walk to the park (with its occasional lampposts), and back. So this isn't anything like the active studying of bats with a detector - but would it work? True, no mic/tablet will identify all the bat calls, but there have been shoot-outs with similar microphones where up to 70% of the recorded calls were identified up to species.

I hadn't heard of the Ciel Micro Trio before.. That sounds very interesting. I think you would get the most satisfaction out of this plus a sound recorder, (I use a Zoom H2N, plenty of others to choose from).

Advantages of the ciel are that it would become more useful as your experience grows. You could start with the Heterodyne, graduate to the FD recordings and sound analysis, and then you have the Time expansion mode (which does give you a chance of identifying the majority of species, I'm told. I have never used one personally, always been out of my price range, until now!).

If you like a challenge, then that would all be a great project to try and find all your local species. I think you'd get more enjoyment if you were finding them, seeing them and identifying them at the same time. Not sure your tablet in the rucksack, and holding a microphone would give you that instant reward.

If there is a Local bat group in your area, you might want to consider joining them for help and advice. Otherwise, keep posting on here, and we'll try and help!

I've got a few of my results online..
http://bat-diaries.blogspot.co.uk/2012/03/story-so-far.html

Best of luck, Peter

Thanks again, Peter, for the excellent advice. I've just ordered the micro trio, since there was an offer valid until August 31 ("International Bat Night"): www.nabu-natur-shop.de/Tierwelt/Fledermaeuse/Fledermausdetektoren/Starterset-micro-trio.html . Let's hope that my local bat population will be just as cooperative as yours, illustrated by your impressive bat-diaries.

Recorders: maybe the Transcend MP330 is an option. With a weight of 25g and the ability to record WAV files, there isn't much to complain - if it works, of course. The combined set-up Ciel micro trio + battery + recorder would be a mere 213g, plus a cable. The tech industry brings down the "shlep factor" - fine with me!

Well, just be aware that it took a few summers to put those samples together! Not just time in the field, but at the PC too. No idea about the recorder you mention. Can't find any details about the recording quality, so it could be a bit of a gamble

peter.jones said:

[...] No idea about the recorder you mention. Can't find any details about the recording quality, so it could be a bit of a gamble

Click to expand...

At least the MP330 is cheap and weighs only 25g.

It also has a line-in jack, is able to record in *.wav, apparently a useful feature, when it comes to feed the data into identification software. Earlier versions of the MP330 had some flaws, it seems, and no WAV ability. Its more recent ratings at the German amazon.de site are not too bad. Nobody raves about the quality of the speaker, but for storage of sound files it seems OK: http://www.amazon.de/gp/product/B007TGW4YI/ref=ox_sc_act_title_5?ie=UTF8&psc=1&smid=A3JWKAKR8XB7XF

I guess I'll bite and play the guinea pig... |:$|

The Ciel company offers the Olympus VN713PC "with Ciel Firmware" for Euro 89.90, but it is on the heavy side, with almost 100g including batteries. High-class recorders like the H2N offer lots of features, and if I'd buy a recorder for a journalistic interview, I'd avoid the MP330 like the plague. But bat recording is a relatively basic task, right? Storing some wav sound files.

As long as the sampling rate of the recordings are good enough to keep the data.. I don't know much about this area. I 've tried to google for more details and found this page:
http://batdetecting.blogspot.com/2011/09/typical-recorders-used-for-recording_08.html#links

which looks promising.

The only other thing to to consider at this point is to make sure you get the right cable from the bat detector to the recorder. Most combinations need stereo to stereo cables, and I don't think you can go wrong with this type of cable.

Thanks. I'll be back to report if it works. The MP330 comes with a line-in cable, so I can hope it will be the stereo version. The bottleneck of the system might well be the quality of the detector, but we'll see. A review of the Ciel Micro Trio ( http://www.batplanet.co.uk/reviews/ce-505-trio-bat-detector-review ) has criticized a detail:

The only noticeable issue that I can see with this detector is that it only has one ‘jack’ point, which renders the detector silent if recording.

Click to expand...

It will be interesting to check whether this is true. That special offer of the micro trio to which I have linked above includes an audio adapter for the simultaneous use of two headphones, something like this:

http://www.amazon.de/Audio-Adapter-Mini-Phone-Stereo-3-5/dp/B00187W9KS

I am an electronics dilettante, but... would they include the adapter in the package, if the Ciel detector cannot serve two audio jacks? If both jacks are receiving an audio signal, why shouldn't it be possible to listen to the sound while it is recorded?

PS. My decision to buy the M500 or something similar is postponed until next spring, but not cancelled. If someone has made practical experiences with such an equipment, I'd remain very interested to hear about it.

I'm sure the dual adaptor will solve that problem. Although a lot of the literature online says otherwise, you can identify the more obvious bats by listening to the FD channel with practise, plus it would be good to know you were actually picking up bat calls when recording.

I think you have done the right thing to go for it with the Ciel.. look after it and it won't lose too much value if you subsequently wish to change to the mic method. Hopefully you'll get a couple of months experience this season, before the colder months limit the activity.

For software to analyse the calls, Audacity and Wavesurfer are both free, and work for me.

Good luck!
Peter

Nathusius's pipistrelle - or not

The new toys are here, yesterday I've recorded my first bat. According to the software, a Nathusius's pipistrelle - but mere 26% probability that the ID is accurate. The books list the "nathusii" as a rare winter guest in Western Europe. Germany isn't exactly "west", but my local source also files it under "migratory" and mainly a winter guest, plus one sighting in autumn. The usual beginner problem to see rare bats where there are none, I guess.

This is how it went, step by step: The MP330 was left at home, my priority was to learn the basics. So I could take only one Time Expansion recording, stored in the Ciel's temporary memory. Many bat calls filled the air, but mostly 45 kHz calls, clear and distinct. I had watched common pips before, and hoped for something better. I guess there were also Daubenton's bats around. What I finally recorded sounded less regular than the other calls.

Back at home, the MP330 got the wav file on my PC. Audacity was used to delete the first and last seconds of the recording, the result was saved in the new file attached to this post (see below). For the rest, I used the free version of "BatExplorer". Opening the wav file, I had to put in a "10" (factor of the time expansion) and a "0" or "1" to select a stereo channel. Analysis of the call plus the suggested two species can be seen in the two screen shots which I add.

Clicking on "suggested species", the software gives 26% for nathusii and 25% for kuhlii. I can clearly exclude the second, as it doesn't live in this area, and the recording took place near a river. But I guess I'll have to return to the place and try again to be really sure. Something else I have learned yesterday: I'll have to acquire a flashlight.

Well done for getting up and running so quickly.. you know what, I think you do have a Nathusius' Pipistrelle there.. They migrate through the UK at this time of year, and can be found near fairly large water bodies with some regularity. The sound analysis peaking at 38KHz looks spot on. The only other thing to consider is the habitat that the Bat was recorded in.. Cluttered Woodland environment, or edge of woodland, often gives a slightly higher frequency than the open spaces where the bat uses a more relaxed echolocation. Chances are it will move on fairly soon.

The software you are using to analyse looks pretty amazing.

Of course, BatExplorer cannot ID with 100% probability if the original audio is noisy or in other respects insufficient. Software like the BatExplorer is indeed amazing. If there is something wrong (or insecure) with the result, there remain a lot of factors to be considered. In particular my own lack of experience.

Ouch. The audio from the temporary memory of the device was re-recorded five times with the MP330 (I wanted to be sure that the audio didn't get lost). My last post refers to the result of the fourth re-recording. I've just repeated the whole process file --> Audacity --> BatExplorer with the 2nd re-recording. In theory, the result should be the same, right? But it is not. Now BatExplorer sees the peak frequency at 33.1 kHz, obviously not a Nathusius!

:eek!:

Well Barbastelle has two calls, one low 30s, one high 30s but I would recommended spending some more time collecting data.. Use the HD and FD modes first to get familiar. And build up your own database of sample recordings.. Guest the Nathusius should go into the pending file for now. Could it have been two bats? Must admit I can't get my head around time expansion and have always gone for FD sound analysis.. Not as accurate, but easier to see the big picture of the night's events

Nathusius' pipistrelle

Thanks for the encouraging feedback. Yesterday I returned to the park and recognized for the first time how many bats we have here. The sheer number of bats close to the river was astonishing. Mainly common pips and Daubenton's, as far as I can say from the recordings - as you'd expect at such a place.

The new wav files contained a nice surprise: one file that may be a better (or maybe my first) recording of a Nathusius' pipistrelle. I've attached two screen shots. The first shows four "blips" (of six) of the bat. However, there also was a common pip at 47 kHz. The second screen shot shows the whole picture. The software offered these ID percentages: Nathusius 48%, Kuhlii 48%, Common pip 46%, with more exotic species like Bechstein's (40%) behind. - But I think the first screen shot is sufficient to convince me that I've recorded a Nathusius'.

Postscript: wav file added (Nathusius pip and common pip).
Tentative conclusion: the 234g equipment works as expected. No, actually a bit better than expected. For the rest of this bat season (about a month?), there remain ten or more "new" bats to be found/recorded in my area.

I think the other night you were lucky to pick out a Nathusius amongst several Common Pips.. Any Soprano Pips? they should be just as distinctive with the peak at ~55KHz.
Daubenton's you should see skimming the surface of calm water.. otherwise, you could be looking at another Myotis Species, maybe Natterer's, which is common in much of UK.

Your most recent recording definitely has both Nathusius' and Common Pip. Talk about hitting the ground running!

A valuable guide on my first steps is an online publication from the Pforzheim Umweltamt. They published the free online booklet "Faszinierende_Fledermaeuse2.pdf" (2013, in German; 43 pages; short: FF2). This source mentions the Soprano pipistrelle ("Pipistrellus pygmaeus", in German: Mückenfledermaus [Gnat Bat]) in a list of 24 bats living in Germany, but FF2 says that the Soprano is missing in Pforzheim. On the other side, I am a little skeptic when a source lists 24 bats as living in Germany, only to claim on the same page that Baden-Württemberg has 25 bat species.

Anyway, even if we don't have the Soprano, there are many other bats to explore in Pforzheim.

Serotine bat

On Thursday I observed, early and fairly visible against the sky, two large bats circling around a tree, maybe 7-10 m high. The largest bats I have seen so far, and I got the idea it might be Serotine bats. The silhouette was so impressive - not the small wings of other bats. Yesterday I returned to the place, after reading a bit about serotines, and watched the two bats again, for ~ten minutes. I am now quite sure that they were serotines.

The attached recording was already made on Thursday. At first I was puzzled why BatExplorer didn't list serotine among the probable candidates. Until I saw the light. The recording actually had caught BOTH serotines, and there were "too many" calls for Batexplorer's taste. So I disabled the entry for "call distance" and adjusted the 40ms manually to 145ms. Voila, suddenly it became a very clear recording of serotines, Batexplorer gave up its resistance.

In the picture one can see that one bat is using a lower frequency than the other. Apparently some bats are used to vary their frequencies when they fly "in a crowd".

Common pipistrelle

A few thoughts on the MP330 recorder. It has limitations, as could be expected. First, it seems unable to store more than 99 recorded files in the "Linein" folder. Attached to PC via USB, after deleting the 99 recordings taken during a walk, the device claims 7.8 GByte of free space. 99 bat wav files are just a total of 30 MByte, so there would be lots of space left for more recordings. In practice this small restriction isn't too serious - at least not for me. When the device is full after appr. two hours, I am ready to go home anyway.

Besides, the MP330 device has no "voice assisted recording" or similar feature for the inline connection. I'd be tempted to try out some unattented recording overnight, if only the MP330 had an ability to "ignore" silence and record just the rare bat calls close to my house during the night, this might have been an idea: put the detector in "frequency division / FD" mode, and record the sound with the MP330. The better audio recorders, like the H2N or Olympus do offer VAD or VAR or whatever. (On the other side, my daily walks deliver enough wav files to play around. Still a thought for a later upgrade.)

From several recordings of common pipistrelles, I post below the one (from two days ago) that seems to combine the usual echolocation call with an 18kHz social call.

HermitIbis (and Peter),

I am in the same situation as you. I am a birder but I would love to be able to identify the bats I see on my trips and even from my window. As you, I fear that if I buy something cheap to start I will end up buying a better equipment in a short time so I do not know what I really want to buy.
My main aim is to clearly identify the species I see, not only the genus (I know that some species make take a while to be able to identify correctly)

I have read this post, reviews from bat specialized websites, and detector manuals but I still have many questions:
- As I understand a HD detectors are great for detecting species on site but it wont identify all species as the recordings are not deteailed.
- FD will allow for better recordings but again not 100% accurate on identifications as some information is lost
- TE will allow for the better identification rate analyzing the recordings at home but these are quite expensive

After all this I have selected three detectors that have the features I undersand I need and are under my budget. These are SSF BAT 2, Elekon batscaner and micro trio from CIEL.
The micro trio seems the best option but I have the following doubts that I can not resolve reading the manual.

- Recordings can be made once at a time using the internal memory on HD or TE. So only one small recording (1s) can be taken home for analyzing which seems a bad thing. It seems it is possible to record more using a digital recorder. If using TE, can you record as long as you want? Or that is only possible with HD? Can you record while listening?

What will be the best way to identify bats on site? Using FD first to get a glimpse and the HD and you have to be skilled to tell which specie it is?
The SSF Bat 2 has a great thing that it tells you the peak frequency so you can automatically change to it to hear it. Can you do something similar using the micro Trio from Ciel?
The Elekon batscanner does the same thing that the SSF Bat 2 but automatically wich is also good.
But, can you record any sounds with the SSF BAT 2 or the Batscanner? Will I miss many identifications because I do not record with enough detail?

As you know I am a bit newby on this and I would like not to throw the money to the garbage. The normal ay should be starting from a low range HD detector but if I can get something better for the future it will be nice.

Regards

Ricardo