Are Bats the Most Underrated Pest Control on Farm?

0:00Welcome to Tramlines, a podcast from Agri. I'm your host Tony Smith putting your questions to the experts. Bats and moths. That's what we're going to be talking about today. Could bats be the IPM solution for managing moths that limit harvestable yield and impact the bottom line for this farm, producing high quality dessert apples? Richard and Fred Chandler, farming as Chandler and Dunn, at Goldstone Farm on the Ash levels in Kent, along with their agronomist Neil Abard from Agri, have been looking at this idea. So Fred, maybe you could start us off here. How did this whole idea come about? So this started during my time studying wildlife conservation at the University of Kent. I was also working part-time on the family farm. And whilst I was working on the farm,

1:06I was listening to audiobooks at the same time, so I could kind of maximize learning whilst also working in China, like build one knowledge at the same time, which is when I came across a man entitled to this book, The Secret Life of Bats. So when I was listening to this book, I was thinking, well, maybe I should get my dad to listen to it. Maybe I could know him in a direction of, you know, using bats as biological pet control on the farm. So then I got my dad to listen to the book and then he found it really fascinating and interesting. And then he got his agronomist Neil to listen to the book as well. Neil was like, damn, this is really interesting as well. Maybe we can try and do something about this. So, yeah. And the book that Freyr refers to is written by Merlin Tuttle and is entitled The Secret Lives of Bats, My Adventures with the Most Misunderstood Mammals. And Richard, when you were encouraged to read this book by Freyr, what did you find? We're always fascinated by bats, but they're one of the things that you don't get to see

2:08the different types. And growing up, I thought we had bats. I'd heard the term hippestrails. I thought we just had hippestraile bats and they were all same size. They're all flitting around and that was bats. And then a while ago, I noticed that there were two different sizes of bats. There was a pretty small one that I associated with with the hippestraile. And then there was a larger one about the size of a starling or a black bird and I was certainly afraid. And I'm sure there's more than one type of bat. And through her studies, she's like, yeah, there are 17 species of bat in England, blah, blah, blah. And 18, so. And then she got her back detector and started doing surveys around the garden and the sort of sort of hub part of the farm and whatnot. And she identified seven species. And I was absolutely gobsmacked. Yeah. And to put that in perspective, Neil, you've got an amazing factoid, having you in terms of, from America, okay. But actually, what the

3:09bat population contribute to the farming economy? Well, it's again, the figures from the book, Millennials book, but then there's one billion US dollars saved. And that is actually saving farmers from spending. Is that that's the saving, is it? Exactly, exactly that. Very expensive they are eating the problems, which are causing damage, which have grown within half to treat in various manners. Brilliant. Yeah. And that's so what for us, you know, here in the UK growing an amazing quality crop, such as these apples Richard, Neil, you've got another factoid is to roughly what that is costing this farm per hectare in terms of spend on insecticides. Yeah. For the control of the moth species, the four problem moth species on the farm, we're spending between five and six hundred pounds per hectare to control those moths to produce the top quality

4:15product that we're trying to do here. Yeah. And what are those four key moths that are causing a problem? We have cuddling moth, that's probably number one, that's the big one, fruit tree tall tricks, summer fruit tall tricks, and then light brown apple moths. Right. And Richard, for you as the farmer, what problem are those moths causing? Oh, they lay their eggs on and around fruitlets and matured fruit. And with the lava hatch, they bore into the fruit. So they'll dig a little ton of right into the centre of the apple or the pear or whatever it is, and basically feed and feed and feed until they're ready to change into their moth. And then they'll burrow back out again. And basically as soon as they've broken the skin of an apple, that apple then becomes unviable as we can't sell it. If they've broken the skin,

5:15got right in and gone through there, they're maturing process and come out then that fruit will rot. And so I'm assuming Richard that if improving, increasing the back population can help you control these pests, it must be a good thing. Absolutely, yeah. We don't want to, we don't want to be throwing chemicals around out in the orchards. You know, it's not good for the environment per se, and it's, it's expensive. We can't afford to be throwing all the chemicals around. So if we've got a natural ally that we can use and we can help to boost their numbers, we've got all the food that they can eat. So Fred, how did you go about identifying the different species of bats that were on the farm? So I use the echo meter touch bat detector. So it's a small module that you can plug into your vine. And it basically,

6:19it can pick up on the ultrasonic echo location that bats produce because they have different species, basically echo-locate in different ways at different frequencies. And this can translate that into a means that basically automatically identifies it and shows you on the screen. It produces like a spectragram, which is a, it means that you can, you can see the sound waves, you can see what frequency they're elevating out, the shape of the call. So you can't always rely on just the automatic features of the bat detector, you also have to like manually verify. This sounds amazing. So you are a bat expert in being able to qualify, yeah, well, you are compared to us, I think. Richard, would you say that frayers become the local bat expert? I'm learning, I'm just learning. We're all learning, I mean, it's fascinating, I mean, she shows me from, and it's like, wow, I didn't even know that happened. But Neil, it is fascinating, isn't it? Yeah, you have to take knowledge here at levels,

7:21don't you? And frayers knowledge is about 500% higher than Richard's, and mine so on bats, it's great though, she's a huge resource for us to have. But Neil, as the farmer grown a mist, and you look at lots of other crops as well, it is this, or does this offer a real potential at IPM route for managing some of these pests? If you think about a bad moth infestation, you know, you can lose 30% of your crop. So on something like Brown, you could be talking losing 20, 30 tons of apples per hectare if you have a bad attack from one of these moths. We're also losing plant protection products. So as CRD changes, parameters, et cetera, we're losing active ingredients, active ingredients that change the rate we can use and the frequency we can use. So there's some big changes within the industry. So if we can utilise the tools on our Swiss

8:25Army Knife of Codling Moth, and one of those is bats, bats haven't really been tapped into. frayer found a paper, a 2002 paper, 2022, 2022 paper, which I don't know if she wants to tell you about, or if she wants me to, but it was interesting this paper she found. Yeah, so I'm kind of basically trying to utilise resources that I had from my degree, which could be access to scientific papers, which is really helpful. So paper by Francis Murphy and Joe Aement, I hope you're pronouncing that right, called pluralistic valuation of Codling Moth Regulation by Brown Longade bats in English Apple orchards. It found that the presence of a single P-oritus, so Brown Longade individual resulted in a significant reduction of 81.06 to 83.68% crop loss per hectare. So one bat, one brown Longade bat reduced the potential problem by 80,

9:2880% across one hectare. I mean, that's quite an amazing factoid. I don't know what you're thinking as you're listening to this podcast, but that's quite incredible. One bat reducing that pest population by 80% across that one hectare. Yeah, it might, sorry, it might explain to only why we have hotspots of moth damage on farms. So when we're looking for the moth population, we put out fair amount traps and rapid aim traps around the farm to catch and monitor the population, and some areas we will have hotspots where there are hundreds of moths being caught, and other parts on the farm. There are less moths being caught. This may be down to the back population on the farm. They've got areas they like and they're heavily feeding on the moths. So we're catching this in the traps. Therefore, we're having less damage. The

10:30sea will be proving that, which is something we're going to try and play with over the next few years. To find out more about how Agri can help with expert agronomy advice for your top fruit, soft fruit and vines, visit agri.co.uk forward slash your hyphen crops forward slash fruit. Right, so Fred, there's the question, how do you influence your back population in your orchards and on your farm? That would come down to habitat management, providing, making sure their habitat is suitable. They have suitable roosting opportunities, and the food population is already there, so there's that. Okay, so share with this. I mean, I don't know anything about bats. How do I improve the habitat for those bats? What can I do? Hydroes, for example. Hydroes are a very good point. And trees, trees are a good

11:33roosting opportunity, like tree holes. The use of bat boxes is one thing that we're kind of focused on, because around longer bats specifically, they like to roost in, like they're kind of like a roostling bat as well as tree holes as well. And should people be concerned about having bats in buildings? Does it limit opportunities for use? Big questions for farmers? Yeah, absolutely. And it's like, like you said, there's a lot of bad rap when it comes to bats. People worry about sharing spaces with bats. A lot of the time people wouldn't even realise that they'll have bats roosting in their houses, because they're just your silent neighbours. They're not really doing anything to harm you. They're just there, like, and I said earlier that a lot of the time they'll be just trying to eat the bugs around, do, they're just doing a great favour. And they're just, I don't know, silent housemates in a lot of circumstances. But like you said, like I just said, when it comes to what you want to do with that space, then it can kind of become the issue, because they're protected by laws.

12:36You have to be very careful about what you do in times of that. Which is also where bat boxes can come in handy when it comes to development and trying to use the spaces in which bats are already occupying. What's the next step? Is it about creating those habitats and building up the population? Is it about identifying where perhaps there are the gaps in bats being prevalent? What are the next steps? Well, I think all of this, so Fred's going to have to do some work with them, helping us identify where the bats are hanging out more often, or where they're feeding more often. We need to encourage bat location or roosting spots. So there's a cavity bat box, which is the one where brown, long-haired bat likes. So we need to be looking at putting some more of those around the farm, and then seeing if they are then being used by the bats.

13:42Obviously, for us, they're protected, so we can't really, you can't go and looking at them, unless you have a license to do so, but you can definitely see if they're leaving and entering them at night. So that's all dusk and that's something we can do. So yeah, encourage them on the site, see what we've got and where we've got them, and then making sure the habitat on the farm is as best as it can be to encourage them. Yeah, and now you look at a variety of crops. What about other horticultural crops? Can bats have a real benefit there as well? Well, there's definitely with stone fruit, so there's a moth called plum fruit tree moth, which is hugely damaging to plums, so there are definitely some opportunities there. Cherries are attacked by tautrix moths again, so that again, opportunity is there. The soft fruit crops, so strawberries,

14:45raspberries, etc, although they can be attacked by tautrix moths because they, most of them are now growing in structures. They seem to have less of a problem there now, but bush fruits, things like blueberries, ground outside, blackcurrants, etc. There's huge opportunities here if we can get a type of working model here, it might be something that we can move out onto other farms. Yeah, it really sounds a real benefit both for the environment and obviously reducing that pest pressure. Yeah, earlier, earlier fray was telling me how many insects these bats can eat. There's an interesting fact where fray isn't available there. Yeah, the common purpose trail, as the name was suggested, one of the most common bats that you would see in the UK, a common purpose trail can eat up to 3,000 insects in one light and run along your back and eat up to half,

15:46it's bloody weight, I think I'm getting that right. Richard, how do you feel in terms of the prospects for your farm business by increasing the bat population? Oh, fantastic. We're all for it. I mean, it's not only is it fascinating, anyway, it's going to save me money, right? Yeah, I have to spend some money on probably some bat boxes and some materials for bat boxes and there'll be various costs and whatnot associated with doing it, but it's something I'm really looking forward to anyway, so when fray is out, they will have a bat detector, I'll probably be there as well. Neil, if you were to bring all of that together, what's the story here for farming? The pressure that farmers run into the moment with reduced income, if they can save some money on inputs and use some free resource, it's got to be the right thing,

16:49but also for the bigger environment, the floor and the floor and the farm. We could be talking about beads, we could be talking about bats, we could be talking about birds, mammals, et cetera, anything we can do to make the farm a more bountiful place has got to be right. And as we come towards the end of this podcast, we could discuss this for hours. It's so fascinating, but what would be your top tips that you'd like to share with other listeners today? Richard, perhaps you'd like to go first? I mean, to a large extent, most are doing this and have been doing this kind of thing for years. With farmers, we've probably renowned for being quite thrifty, so any kind of free resource is a big win for us. But working with the environment, you wouldn't stay in the farming business for generations if you were just stripping the environment, you have to work with it. And Fred, from what you've learned and brought back to the farm,

17:54what would you share with other farmers? Yeah, I would say that this is a fantastic and valuable opportunity for both farmers and also bats. We need to work with nature. We can't just a lot of people kind of fall back on instant gratification. And what can I do right now that gives me all of this money right now? It's not going to work. It's not sustainable. It's not a long-term method, we have to think about the long-term in order to actually maximize your yield and all your financial profits, et cetera. So I think that bringing appreciation to bats, and again, let's share the value in working with nature to help ourselves as well. It all sounds very exciting. Neil, what would be your practical top tips you would like to offer farmers and growers? The best advice would be taken from a local bat conservation trust representative, and I think they're very, very approachable. But we must remember we need to be

18:54thinking about a mixture of bat roost boxes because different species of bat will use a different type of box. A bit like a bird box, one that's suitable for a sparrow isn't suitable for a robin. So we need to be thinking about the boxes we're putting up. Thank you, Freya, Richard and Neil for a fascinating insight on how bats play a valuable role in pest control in apple orchards and other crops. Do stay tuned here on tram lines for recent episodes on crop resilience, varieties, nutrition and much more. If you have any questions for our experts that you'd like answered, email them into info at agree.co.uk. That's it for this podcast, but do tune in again as we meet the experts throughout the season, exploring the many immediate and longer-term questions for growers and farmers in the UK. See you next time.