BatChat

Jon Russ

December 29, 2021 Bat Conservation Trust Season 3 Episode 28
BatChat
Jon Russ
Show Notes Transcript

S3E28 This week Steve is joined in a Derbyshire churchyard by Jon Russ who is an expert on bat echolocation calls. They discuss how Jon got into studying bat calls, his latest book on the subject and his passion for Nathusius’ pipistrelle bats. Jon's latest book "Bat Calls of Britain and Europe" is available from Pelagic Publishing and is aimed at anyone interested in bat echolocation. It contains introductory chapters to the subject as well as more advanced topics such as sound analysis. As Jon says in this episode if you want to get into learning about bat calls the best place to start is to get hold of a bat detector. Your local bat group are likely to be able to lend you a detector and you can learn more about them on our website here. Jon's other passion is Nathusius' pipistrelles and he runs the website dedicated to this species containing distribution maps, identification tips and other information about their ecology.  Listen to our earlier episode about Nathusius' pipistrelles with Dan Hargreaves here.

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Steve Roe:

Hello, I hope you are enjoying the festive period. Today we continue in this series of BatChat with a bat worker who is an expert in bat echolocation calls. And it's just published a new book on the subject. I'm Steve Roe, a BCT trustee. And if you're a regular listener, welcome back. And if this is your first time listening to BatChat, welcome along. Episodes are released every second Wednesday from now through to the spring. And you can join the conversation online using the hashtag BatChat. that's all one word. As we meet each of the guests in this series, you'll hear stories from people working to make a difference in the world of bat conservation. People who care about individual species, people who concentrate on one particular part of bat ecology, and people who are working with bats at a landscape scale. As well as keeping up with the latest news and hearing from people in the world of bats. We hope that you'll be inspired to get involved because bats need our help. In this episode, we're with someone who specialises on one particular part of verticality, specifically echolocation calls. Today, I'm in my home county of Derbyshire and I'm taking you back to a summer's evening, when I sat down with John Russ who explained what he was doing in Derbyshire as Twilight started to fall.

Jon Russ:

Well, we mainly sat in the church, because you've, you've asked me to do this podcast or you sort of pushed me into doing this podcast, I feel! Well, we're starting this church, because we're here this evening to survey this beautiful church, St. Peter's Church never sail as part of the bats in churches project. And the aim of this is to try and come up with some novel approaches or methods to try and deal with the back problem of this church. So air surveillance this evening to try and find out exactly what species we have here. And where they're roosting, where the holes are, and what sort of mitigation we could put in place to try and minimise the droppings really, they're getting inside the church,

Steve Roe:

What sort of species that they got here?

Jon Russ:

All we found so far is brown long-eared bats. That's not so there isn't more we found some smaller pipistrelle-sized droppings in here. But we've not managed to find any all summer I have a feeling they're not back.

Steve Roe:

So your name is coming up quite a lot this week, because you've just published a rather thick book called Bat Calls of Britain in Europe, which is quite hefty volume. How did you get into echolocation? Before we go on to the book? How come you are a specialist in echolocation calls?

Unknown:

I suppose that question is really how did you get into bats? Because the first thing I did was was bad echolocation and that social calls. I was doing a degree in zoology at the University of Aberdeen. And in the final year, you have to do a project and honest project. And usually they publish a list or on the wall of projects that you can do and supervisors you can do the projects with. And two of them looked quite interesting and one of them was with Dr. Xavia Lambin. And it was looking at dispersal in Orkney voles. And the other one was just called bats in bridges. And that was within with Paul Racey, who was the Regis professor of zoology at the time. I thought well, I'll go and have a look at this Orkney voles one. So I went to meet Xavia. It took me out of the back of the lab. And there was a small concrete enclosure measured about five metres by five metres with some longish grass in it. And he said, what you'll be doing is you'll be putting little red flags on Orkney voles letting them go in this enclosure and watching them all summer. And I thought, Oh God, I didn't think I could. I could spend all summer doing that. Let's find out what this bat one is! So I went to see Paul Racey and he was quite enthusiastic. He said it'll be absolutely brilliant. You'll be out you'll be on a rubber dinghy on the river Dee and the river Don going under bridges with a torch trying to find mating bats. And I thought that sounds a bit more interesting really than looking at Orkney voles as it happened the the boat thing didn't happen. The rubber thingy thing didn't happen for I think probably health and safety reasons. But I did spend a lot of time that winter lying autumn lying under bridges staring up at the underside, listening to that lovely [Jon does an impression of pipistrelle social calls] the social calls of the soprano, pipistrelle,

Steve Roe:

That was very good!

Jon Russ:

Thank you very much. I've had a lot of practice. I'm quite good at time expansion ones. So that's how I got into bats. And it was it's actually Jens Rydell, who unfortunately passed away this year. Jens is very, very well known in the bat world, and it was Jens that taught me the fundamentals of echolocation. The first time I was given a bat detector to Paul Racey, he said, go out with Jens and it'll teach you all about bats. So we went out to Seaton Park in Aberdeen, and Jens got a stick and he was scratching sonograms and doing exactly what I did then making noises. That sound like teaching me how to tell the differences. And then he took me out for two or three nights along the river Dee in Aberdeen just teaching me how to separate the different bats and what the social call saying like I think probably the first time I turned on the bat detector, I got completely hooked. And you've got this completely silent black night and turn on the sector and suddenly the whole night comes alive. It's absolutely amazing. I find it pretty entrancing to be honest. And I still get that same buzz today, actually, when I tell them that pipistrelle flying around. I mean, it's fantastic.

Steve Roe:

And what sort of detectors were using back then how many years ago soaking now?

Unknown:

That's a good question. I'm, I think, probably 20 years, maybe? Possibly even nearly 25 years, long, long time ago. And I was using it was, yeah, I was using an S-22 bat detector. If I remember rightly. I don't know if anyone's still got any of those. I think it was made by ultrasound advice? I'm not totally sure. And I also used that box three, which was very, very good. Detective, I still got that detector. still use it from time to time. So very good. Yeah brilliant little things. So from there, you did your PhD in that got you into bats and eventually into bat echolocation. You then published what I considered the original back course book, which was a kind of round, it was called that had like a green and red and blue bats on the front. Very, very strange cover was it looked like someone had drawn a picture. Actually, I shouldn't say this case, the artist gets offended! Basically, I do feel reluctant to say it, it did look like someone had painted bats and then not let it dry properly. And it's made into this sort of grotesque sort of back image on the front. And I think it was called back calls of Britain and Ireland. species identification, I think, yeah, that was a long time ago that that started read. I didn't, I didn't really intend to publish a book. I just started putting a few notes together when I was in Ireland, of how to separate with different species. And it was really just for people in Ireland. And someone said, Why don't you expand it to include some other bats in Britain? So I had a go at that. And some of the bats that hadn't had an awful lot of experience with at the time. And I think I showed it to some chap, one of the conferences, and I remember he said, Well, you really should publish this somewhere. It was Andy McLeish, who eventually decided to publish it. So yeah, that was, I don't know, when when was that?

Steve Roe:

I want to say 1990-something. Yeah, that'll do.

Unknown:

1999. Maybe.

Steve Roe:

And was that the precursor to then what became the first edition of backhauls of Britain? Did that lead into that was that very much a separate publication?

Jon Russ:

It did lead in to I always intended to publish European bat calls book after that one. Originally, it was going to be with Colin Catto. I don't know if anyone remembers Colin. And he worked for the Bat Conservation Trust for for many years. Now lives in Thailand. And that project failed. But then I tried to start it again with Danillio Russo. And he basically he didn't have time, really. And I didn't have time, and we just left it. Basically, I met Nigel Masson, with Pelagic Publishing at one of the conferences. And it was really him that kick started the whole project. I mean, basically, he kept giving me deadlines. And I mean, everyone hates deadlines, but I'm quite good at trying to stick to them. And I sort of stuck to his better than I thought I would. So yeah, that really involved collecting lots of calls that people sent me going out and doing a lot of my own field work. And also starting to augment some of the chapters from the previous book on sang analysis and cool identification. The physics of sound. I felt the first book really was pretty scrappy. As I said, it was never really intended to be a book. It just got thrown together. The second one I did really intended to be a published book. So yeah, work quite hard on that. I think that probably took about. I mean, the whole thing took about 10 years, but really the last bit took about, I think, three years to put together trying to fit in or handle the bat surveys and bat work as you know. It's not an easy thing to do. But yeah, eventually published that.

Steve Roe:

10 years was it?

Unknown:

I mean, do you Have you any idea how many copies have been sold? I see it on every consultants bookshelf, it's clearly a very popular book. So what where did the need for this new one Bat Calls of Britain and Europe that's just been published this week. Where did that need to add in the European species come in? Yes, there's something I forgot to point out. I did intend to do this European book beforehand. But I just realised that Danillio was too busy, he was going to cover the European species that I couldn't do. So I just decided to just do this, just do what I know. It's just the the British bats, this new book, I've been meaning to do it for years. And Nigel kept pushing me to, to do this book. And I thought, Well, I mean, it's gonna be really easy, isn't it, just throwing a few of these European species into the existing book? Not gonna be difficult. And then I started looking into it. And I started to get worried. Because I realised, I don't actually know a lot about the species. And there's actually a lot. There's a lot more species in Europe than we just get in Britain. Yes, I did start to panic and bid for how am I actually going to do this? And then I hit on the brilliant idea of actually getting someone else to do all the work for me. Well, I said, What I thought was, why not get some experts on Europe, who are experts in their field, these particular species, and get them to write the chapters for the different species, because they're going to allow it know a lot more about it than I am. And then I expanded this into also getting people to write different chapters in the other section. So for example, Grace Marsh wrote the chapter on acoustic communication in bats, which is fantastic chapter. Arjun Beeman and his brother Martin helped to write the chapter on Bats and sound. Phillips Briggs helped write the call analysis section. Um, so really, I was just drawing on experts from from around Europe. So just helped me put this thing together early. And how long has it taken to put this together? Then?

Jon Russ:

It took four years, I think, I think it was, I think it was three years really, really hard work. And then four years tweaking it. Um, so it was a lot quicker than I thought that the hardest bit really was because you're using so many different authors. And I think this is off the top of my head. But I think there's about 40 authors in this book. The hardest bit is, is managing over different authors, authors and making sure everything is consistent across chapters, and also making sure everyone's handling stuff in on time. Because some some people handed stuff in within a month and some people it took them three years. And I have to say I was one of the people for years to hand in some of the chapters. But I mean, we got it together in the end. And who's aimed at these aimed at? Yeah, oh, it's aimed at absolutely everybody. It's one of those. It's a bit like Stephen Hawking's his book you put on the coffee table, don't actually read it, just go out and buy it. Well, it's aimed to everybody, really, it's aimed at beginners. I mean, you can mean, there's a lot of basic stuff in there, it may seem a bit intimidating at first, when you first open up, there's a lot of information in there. But you can just pick, you know, pick and choose which bits you want to read. So it's aimed all the way from beginners all the way to professional consultants, and also people doing that research. I mean, there's there's references throughout all the information contained within the separate species chapters and the other chapters. So I suppose anyone who has any interest in that or not, but buy it for someone for Christmas.

Unknown:

And apart from the book, if people want to get into that setting, where would you recommend they start? Well, the first thing start really is just to get a bat detector you get some very, very cheap bat detectors. Now, a lot of the ecological consultancy shops sell them. I mean, you can you can actually pick up I think there's ones, Hanes bat detector, which you can make yourself just sold of the bits together. I can't remember offhand. But I think that's about 30 quid, like good cheap, that sector about 60 quid, and just go out there. I mean, you'll get as soon as you turn the batch sector on, I promise, you'll get hooked. And the night will come alive, you'll start to hear and see these bats everywhere. Because, of course, as soon as you start hearing them, you'll see them as well. A lot of us walk out in the evening and haven't got a clue what's flying above our heads. But you turn one of these things on and you'll see straightaway. So, I mean, the first thing to do, I think is get upset. If you want to go out and try it. I'd recommend going to your local bat group. There's so many bat groups. I think every county in England, Scotland, Wales, and Ireland actually have bat groups. So find out who your bat group is It's easy enough, you just go to the Bat Conservation Trust website and hook up with them. They'd be more than happy to take you out bat detecting. And what's your preferred bat detector? What do you use it a minute? That's that's a difficult question as well. Favourite bat detector I think my favourite bat detector is the first detector that I used for research. I kind of digress like because the bat detector I probably used for research as in to research something to make a published paper was a it was the microphone of an S-ww bat detector connected to a high speed rack L tape recorder, which was a massive thing. I mean, it was the size of a size of a small suitcase, and I had to connect it to a petrol generator. So it wasn't the most portable thing that I use this to record the ultraound of the social calls of soprano pipistrelles. But to answer your question, I suppose the back sector that I still use is the Pettersson D-980. I still think it's a super bat detector. I think it's probably because I'm completely used to it. I've been using it for, I don't know, 20 years now. And it's, it does heterodyne, frequency division and time expansion. And I think it's just my favourite detector. But there's lots of other detectors at the moment. At the moment, there's the Peersonic detector, which is absolutely superb for the price really very clear recordings. I use a Duet, because the heterodyne is superb on that very, very easy to use. I'm also using Pettersson use want me to list a big list of bat detectors. A Pettersen M500 384. So you can have live visual representation of the signs, you know, the sonograms in the field. And then a few static detectors like the batlogger. I think that's, I think that's about it. So at some point along the way of the last 25 years. I mean, in amongst during the PhD doing a consultancy work writing several books. You got really interested in the Nathusius' pipistrelle? Where did that interest come from? That was what I was doing my PhD at Queen's University Belfast. But PhD was to look at no one had really done any research on bats in Northern Ireland before. And the PhD really was to do whatever I liked. But one of the things was to survey the whole of Northern Ireland for bats, which was pretty difficult task. And I went about doing it by surveying one kilometre squares, random one kilometre squares throughout Northern Ireland, using a time expensive detector. And on one of these squares in Antrim, Hampton town, which is northeast of Lucknow, which is the massive water body in the middle of Northern Ireland. I was there one evening, and just heard that classic male social call of a Nathusius' pipistrelle, which sounds a bit like [impression] and I just knew immediately having heard recordings that it was a Nathusius' pipistrelle and I knew straightaway, I got one. And myself and James O'Neill, a colleague of mine at the time, went back over several nights, and caught a few of his bats and found out that we've discovered this maternity colony of Nathusius' pipistrelles, which was the first record for Ireland. And I think it was the second record for the United Kingdom maternity colony that is, I just, I mean, I was just quite pleased about that, to be honest. And I just wanted to find out more. And I thought, well, I'll I looked at John's Speakman's paper on it. I think it's zoological Journal of zoology published it him. And he'd find, I think it was 22 records of Nathusius' pipistrelle in Britain. And he'd he'd looked at the data and seen that there seem to be these little peaks in this little peak in August indicating that maybe the bats are migrating over here. And John, John concluded that they were migrating over here and overwintering and then flying back in the spring. So I sent out this questionnaire to all the bat groups to ask if they had any records that you sent me. So they could send me and I think every bat group, apart from one replied, not all of them had records I think about 40% did. And I just started collecting data really from there. So I've just published a couple of papers over the years and I've gradually been collecting data. I'm trying to put something together at the moment, which is showing again, this seasonal distribution. It's very, very clear now that you're getting these brilliant peaks in spring and autumn which exactly coincide with those spring and autumn migrations. But you're getting records all year round. You're getting hibernating bats and you're getting back to here in the summer. But also something I haven't published yet is the gradual spread that we seem to be getting from the

Jon Russ:

So that work. And those records you've been south east and the the Northwest, across in a sort of westwards direction, which is very interesting. I'm still trying to work out whether this spread represents a real spread, I think it is, I think they are gradually increasing their range throughout the British Isles, particularly when you look at things like we find a lot of records around large water bodies, and these reservoirs and a lot of these reservoirs, they're quite new, really, they're relatively new, some have only been around for 30/40/50/60 years. We're getting Nathusius' pipistrelles loads of those. And I find I find that quite fascinating. I particularly find Northern Ireland fascinating because they seem to be quite common there. And you've got this huge water body lock now. You've got locked bag, which is north of that. And you've got an upper and lower Loch Urn in County Ferman the West. And you get Nathusius' pipistrelles everywhere, they're all around the place. I've always wondered whether I'm not totally sure that they always wonder whether it's some sort of remnant population over in Ireland, you know, they sort of been there all along. Whereas in Britain, they're starting to recolonize. But don't don't ask me for particular details, because that's maybe a pie in the sky type stuff. I think I need to think more about that. keeping over the years, helped kickstart the new thesis paper trail projects. What sorts of impact is that project had on that conservation?

Unknown:

Well, that project, I think has been superb. That was a Dan Hargreaves had a lot to do that the method using the acoustic laws and the heart traps was superb. I mean, instantly, they they got dozens and dozens of new records from different lakes, and all over all over Britain. And and some of the fantastic things, which I guess has been in a way proving what John was saying years ago, was that we're getting bats crossing, clearly crossing the North Sea and the English Channel. I mean, they rip the records of ring bats that we've heard, I think, from Latvia and Estonia. Over here, I think more recently is one in Russia. And western Russia has been discovered over here. It's perhaps incredible how far these bats actually fly. I guess that's, you know, one of the most exciting things I think to come out for the project. I think genuinely just the the huge increase in records has been superb. And everyone's aware of them. Now, everyone's aware of Nathusius' pipistrelle. And when I started looking into them, I think everyone just thought, well, we don't really get them. And so you don't really listen. And it's a bit like the common soprano. pipistrelle, isn't it. I mean, everyone just thought, well, they're pipistrelles. And then, you know, gosh, John started to do work. It's actually separating the species and discovering that they were actually different species, the common soprano. And it's a bit like them. Theseus you know, until somebody says, you know, maybe we should go out and look for these a bit more. We don't really, which is why we need to really start actively searching for these, you know, Geoffroy's bats. What else?

Steve Roe:

Pond bats? Yeah.

Unknown:

Parti coloured bats Khul's. How do you search for Khuls because they got very similar. They're within that same echolocation range? Yes, I I don't think you can separate them. Some people say there are small differences in the application that I have to I'm not an expert on Khul's at all. But you can definitely separate them on the social calls. And it's very, very clear. And they're finding quite a few records, aren't they? It's in the in the southeast. Yeah, I can't name of the place I can't remember. Do you remember? I sent a record a few weeks ago as well. But I mean, they could be they could be spreading throughout the UK. What's been your most memorable battle experience over the last 20 odd years? You got one? What an awful question! Most most memorable bat experience. That's that is really hard. I think think I have just one experience. I just have lots of experiences. I mean, you know, I worked in Madagascar for I went there on four separate occasions and that that was absolutely amazing to see. To see some incredible bats are in the most exciting bat. I think I caught over there. And yeah, that's probably one of the highlights was was the Malagasy sucker footed bat is absolute incredible. It's got the suckers on its wrists and it's and its ankles. And it's not quite like the sucker bats that you find in South America is a different system for, for sucking on things actually uses dry adhesion for it sort of sticks on to rolled up banana leaves and ravenala leaves and roosts inside them. So I think that's one of the highlights is working Madagascar and seeing the sacrifices and all the other bats and also living out in the rain forests getting covered in leeches and living on beans and rice was quite experienced quite a memorable experience.

Steve Roe:

So when was Madagascar and why were you out there then?

Jon Russ:

I was there originally in 1999. And it was a it was a university project with the Queen's University Belfast. And we really just went out there to is an inventory of the bats in Madagascar, the main aim really actually was to catch as many different species as we could and try and come up with a cool library to make it easier for the for the researchers in Madagascar to identify bats without actually having to catch them. And I think we did quite a good job at the time. And we left them back to Texas when we left. And we did a follow up project. I think it was a couple of years later to do the same sort of thing, but in different parts of the country. And I went back there two years after that. With Richard Jenkins, who was doing a dark he had a Darwin Initiative Grant to basically set up an NGO about NGO in Madagascar. And as part of that I went out there to help do some research in different parts of the country. Again, it was a bit like doing bath inventories of different eras find out what they had. That was quite exciting.

Unknown:

Nice. What don't we know about bat echolocation collocation? Do you think there is still left to learn? I think there's a lot to learn about bat social calls. And I say this really because it's something I'd still love to be involved in doing research on bat social calls. I think it was a real passion of mine. When I got into it. I still get buzzed listening to as I said earlier, pipistrelle soprano pipistrelle, Nathusius' pipistrelle, common pipistrelle social calls. I'd really love to find out more about the function of phases, there has been a lot of work on it. But there's still a lot of work, there's still a lot we don't know. I mean, we're still categorising, all these calls into a type B type, type C types. And we're attempting to try and categorise these into their function. But I don't know whether that's entirely valid when we're putting them into these categories A, B, C, and D. And I really, there's so much more work to look at what what the function of the separate social calls are.

Steve Roe:

Yeah. So finally, then what are your views on auto ID?

Unknown:

Your final question is on auto ID Yeah. Well, I suppose when auto ID came out, it wasn't really that great. I didn't, I didn't really think highly of it. But recently, I mean, I'm talking really visually in the last sort of year, I think there's been some huge advances with auto ID, things like the BTO acoustic pipeline seemed to be really, really good. It doesn't always get it right. And I don't I don't think these are the things ever, we'll always get it right. But then humans don't always get it right, either. And the solid solid that some of that Martyn Cooke has been working on, I think is really, really good. It's very impressive. But they shouldn't be used alongside I think using a manual bat detector. I think the to complement each other. And one of the huge things, one of the great things I find about auto ID stuff is it gets rid of the pipistrelles to start with because purpose doesn't make up 80 to 90% of a cause you're recording, particularly you're leaving at static protectors. And if you can get rid of a lot of those, and maybe some of the other species, you know, you can concentrate on just looking at the more difficult ones, which sometimes these auto ID systems can't pick up on that, as I said they should really be used. I think they should be used alongside using human methods, as it were. Yeah, I'm not sure that's that's a sensible answer. Jon Russ, thank you very much. I'm going to force Jon now to sign my book!

Jon Russ:

Thank you very much.

Steve Roe:

And thank you to Jon for spending the evening with me back in summer. And thank you to you for listening to this episode. I hope you've enjoyed it. If you take a look at the show notes, you'll find a link to Jon's new book as well as advice on bat detectors. You'll also find a link to an earlier episode from series one when I joined Dan Hargreaves on the south coast on the hunt for Nathusius' pipistrelles. Now, a couple of episodes ago, we launched BatChat's first ever competition. children's authors Emma Reynolds and Angela Mills have kindly donated prizes. Angela has donated a copy of Bobby the brown long-eared bats signed by both Angela and Chris Packham. And Emma has donated a copy of her newly released book Amara and the Bats to enter the competition to win one of these brilliant books. All you have to do is write us a review about this podcast BatChat. And the two winners will be picked at random at the end of this series. Not all podcast apps allow you to leave reviews. So if you're an Apple device user, leave us a review on the Apple podcast app, which is already installed on your device. If you're an Android user, you can leave us a review on the podcast addict app. And if you're not listening to this on a mobile device, you can write your review on the pod chaser website. instructions of how to leave your review in each of these places can be found in the show notes of this episode. Remember, we need to be able to contact you if you win. So when you leave your review, make sure you give us your twitter or instagram handle in the review. If you don't use these drop us an email to comms at that stock talk.uk with a copy of your review, we're only able to post the prizes to addresses in the United Kingdom. And if you missed any of that, it's all in the show notes of this episode. Series Three of BatChatcontinues in two weeks when I'll be joining Martin cook an expert in auto analysis in Staffordshire on hunt for Brandt's bats, and I'll leave you with a taste of what's to come in that next episode. I'll see the.

Martyn Cooke:

So by recording the bats that are actually leaving the cottage here, we know that you know the those are Brandt's recordings. And then we can use those for from helping us to do manual identification of bats, but also for training data for automatic classifiers.