Myths, Misconceptions and the Challenges of Bat Conservation - Associate Professor Emma Stone

The Director of the Milner Centre for Evolution, Professor Turi King, talks Associate Professor Emma Stone about her research. Emma leads the Bat Conservation Research Lab. Her research is around conservation biology, in particular the behavioural and ecological responses of wildlife to changes in the environment. She's also recently been awarded a lottery fund grant for a citizen science project, the North Somerset Bat Survey, in collaboration with the North Somerset Council.

Episode Transcript

(00:02):
Hello and welcome. You are listening to a podcast by the Milner Centre for Evolution,
at the University of Bath. I'm Professor Turi King, your host, and today I'm talking to
Associate Professor Emma Stone, who leads the Bat Conservation Research Lab. Her research is
around conservation biology, in particular the behavioural and ecological responses of

(00:23):
wildlife to changes in the environment.She's also recently been awarded a
lottery fund grant for a citizen science project, the North Somerset Bat Survey,
in collaboration with the North Somerset Council.Emma I always love hearing about what it was that
got people into the research area that they're in. So, what was it for you?

(00:43):
Well, I think with bats they’re so unusual and they're really understudied. So, it was wide
open as a topic for me. So, when I, sort of, realized that I'm actually quite interested
in understanding why species are endangered and how we can, like, help conserve them,
that was my driver rather than the species itself.I suddenly sort of opened the doors to lots of

(01:07):
different species that I could work with. And in the UK particularly, there's lots of
challenges around bat conservation because they occupy lots of buildings, they create a lot of
conflict. And so, because they're really heavily protected, there's lots of need to understand
how we can best mitigate those challenges.So, I started to do a bit of consultancy
work at the start of my PhD and realized we’ve got some really cool bats, and they

(01:31):
do lots of really cool behaviours throughout the year, they've got a really interesting life
cycle. They're quite fascinating if you're into evolutionary biology. You know, the evolution arms
race in between bats and moths, how they’re sort of fighting against each other and who's winning
at any given point. And then I realized, well, strangely enough, hardly anyone works with bats,
and we don't really know that much about them. So, there's lots to be done, particularly

(01:54):
around conservation, there's tons to be done.And then alongside that, their PR is not so great,
not many people like them. And I always like the underdog. So that was a win win for me as
well. So that's why I started to work with bats, and it's just gone from there really.
So, tell me about the evolution of bats.Yeah. So, they're really fascinating, so they've
been around for millions of years. You know, they've evolved over time into two distinct

(02:16):
groups. So, you've got fruit eating bats and mainly insectivorous eating bats. So, you've
got these fruit bats they’re using their eyes and smell. And then you've got the echolocating bats,
insectivorous bats, which are using echolocation, which in itself is fascinating. And the fact that
they've evolved to see with sound is a whole topic in itself that you can just get lost in.

(02:37):
So, over time we’ve got these two groups, and we've got over 1400 species globally,
and in the UK, they represent about third of all mammals. So, most people don't realize that,
that they're really abundant and they're the only mammal that have the true power of flight. So,
they don't glide through the air, they actually fly as birds do. So, they're quite agile,
they're quite fascinating in many ways.Yeah. I mean, I think bats are really cool,

(03:01):
and you mentioned this thing echolocation, so for people who don't know what echolocation is,
what is echolocation?Yeah of course. So,
it's how bats see in the night environment. So, they've evolved to live at night which very few
species do. And to do that you think to yourself, well how on earth are they getting around. How are
they finding their food? Well, rather than using vision, they use echolocation. And

(03:22):
echolocation is the same principle as sonar. So, it's same as what dolphins, etc. use,
where they shout out a noise and they’ll wait for the echo to come back as that sound bounces off
an object, and how far they are from something is determined by how quickly that echo comes back.
But what's fascinating about bats is they've evolved a really diverse range of echolocation

(03:44):
calls, to differentiate between species. So, when we work with bats, we can use
ultrasonic detectors. So, bats echolocate in ultrasound, and as they fly throughout
the night environment it guides them through, they can see what's around them, the objects.
Some species are adapted to fly in really cluttered environments, so like dense

(04:04):
woodlands. And they will have different calls to those species that fly in open environments,
like fields. And some people always say to me things like, oh, bats, you know,
don't they get stuck in your hair? Well, actually, their location doesn't allow that
to happen because they're so good at seeing with sound. So, in fact, if you have a spider on a web,
they can actually see what side of the web the spider is on. So, they know where to approach

(04:28):
the web, from which side, which I think is quite fascinating considering its complete darkness.
So why do you think bats have such a bad press, particularly because people hardly
ever come into contact with them, really.I think there's a historical fear of bats
because it's fear of the unknown, right? So, as you say, you don't see them. So not having

(04:49):
any direct contact with the bat, you might see it in the garden, but it’s just this fleeting
shadow that's flying around. Whereas birds, you get to sit and watch them in the daytime.
You don't really get to do that with bats. So, I think there's a bit of fear of the unknown. Plus,
of course it's nighttime and Halloween and, you know, all the historic links to Batman and,
you know, all of those negative connotations that we've had around bats for many years. Spooky

(05:13):
nighttime Halloween type associations, don't do bats any favours whatsoever.
And then, of course, Covid pandemic, all linked back to bats, you know, they carry many diseases,
and we know that they carry coronaviruses. And the original DNA sequence, the closest one is from a
bat. So, there's a whole range of reasons, I think why people are fearful of bats. And in the UK, I

(05:36):
think we're also challenged by legislation because bats have had historical declines across Europe
and globally. But in Europe we've got quite strict enforcement of legislation. And every bat species
in the UK is legally protected to a high level, to the point where if a bat was in your building and
it was in your loft, legally, you're not allowed to go into that loft unless you have a license.

(05:58):
So that can create a bit of conflict for people, particularly when people are developing homes,
or they just want to do a barn conversion or whatever it is they want to do. All of a sudden,
bats are a problem because they're going to cost you a ton of money. You're going to have to get
surveyors in. You're going to have to pay for a license. So, I think all of these things make
people fearful and have negative perceptions around bats. But having said that, you know,

(06:22):
there's lots of opportunity for good PR around bats because they're so fascinating. So, it just
needs people to understand a bit more, I think.And that's really important because bats are
actually really an important part of our ecosystem. How can… let's promote bats.
Yeah.What's important about bats?
This is an easy one. So, you know, we know a lot about biodiversity now and what role

(06:42):
they play in sustaining our wellbeing. So, they provide what we call ecosystem services. And so,
they're pollinators, because you have nectivorous bats which are basically the
equivalent of hummingbirds. So, there are some plants that are called chiropterophilous plants,
which are only pollinated by bats. So, they've evolved completely with bats. So,
without the bats, those plants wouldn't exist.They also control insect pests. And there was

(07:06):
a study a little while back in America that showed that in the absence of bats,
farmers would be having to pay millions of pounds per year in pesticides. So, they’re
controlling insect pests, they're transporting nutrients through the landscape by doing that,
through their poops. And they're also really strong indicators of ecosystem health.
So, if you've got a variety of bats there, they're having to eat a whole range of insects,

(07:30):
that means it's quite a healthy ecosystem. So, working from the bottom of the food web up,
you know, through the insects, up to the bats, if there's lots of diverse bat
species and plenty of them, we can know that it's going to be a good, healthy ecosystem.
So yeah, they're really important for us.So, tell me about this arms race between moths
and bats because that sounds really interesting.No, it's amazing. Of course this is the

(07:52):
insectivorous bats. So out they are flying around hunting their insects. And of course,
the insects have got to try and evolve to avoid being killed and eaten. So over time,
bats, you know, evolve echolocation and they use their echolocation calls to what we call target
locate an insect, and then they'll home in on the insect and they'll go in for the kill to eat it.

(08:13):
So over time, what moths have done is they've evolved a tympanal organ, which is an ear. Well,
some moths have. And their tympanal organ is specifically tuned in to the certain species
that likes to eat them. And then, of course, they can hear the bats coming. So, they then
evolve all these different evasive procedures. So, like doing spiral dives to the floor,
etc. And in response to that, the bats started to turn off their echolocation calls. So, they turned

(08:38):
into what we call whispering bats. So, they went really quiet, went into sort of like stealth mode,
and then evolved longer ears so they could hear. So then instead of using echolocation,
when they get close to the insect, they listen to the wing beats of the moths. So,
you've got this constant evolutionary arms race.So now we discovered more recently, for example,

(08:59):
there's certain moths that have developed striations on their moth cells. So, using really,
really high-powered microscopes, we put the moth wings under the microscope because they
were able to avoid detection by bats without having any, sort of behavioural response. So,
some moths would fly to the ground and go still because they know that the bats are listening

(09:19):
for wing beats, these moths would just carry on as normal. And we are thinking for years,
how on earth are they not getting eaten?And then we discovered by looking at their wings
that they've got these little striations, these little lines, these grooves on their cells of
their wings, a bit like a sound room where you see, you know, in soundproof rooms, you have that

(09:40):
foam on the walls and that absorbs the sound. Well, the moth’s wings are doing exactly that.
So, the bat was echolocating, shouting out it’s sound, and then it was just being
completely dumbed by the moth’s wing. So, it would just completely soak up the sound
and no echo would return. So, the moths were effectively acoustically invisible to the bats,
which I think is fascinating, you know, that they can evolve over time to have

(10:03):
these strategies and it's just ongoing.So, if you're an evolutionary biologist,
go and work with bats because there's lots to be done there. And it's incredibly fascinating.
And you've taken us really nicely into something there because we are changing their environment.
Yeah. Sure.So how are we changing their
environment and how are they reacting to that?Well, I mean, it's multifaceted, isn't it.

(10:24):
And it's not just bats, it's all biodiversity. But again, like we touched on, bats are really
good indicators, and they occupy the nighttime environment. And that's changing significantly. We
are daytime animals, you know, we like everything to be nice and bright. But for certain species
light is not good, you know, they're adapted to nocturnal environment. And we have circadian

(10:45):
rhythms, so our body and our system is dictated by the light dark cycle, just the same as bats are.
So, one of the big ways that we're really impacting bats is through artificial lighting. So,
we're doing a lot of research around that and trying to understand really how it
affects their behaviour and how that might have knock on effects for their survival and their

(11:06):
fitness and then conservation status, that's what we really want to get to.
And because across the world, lighting is increasing globally, but not only is it increasing
globally. Previously, it wasn't really considered light pollution because we see it as a positive
thing, you know, light it up and then you're safer and you can see where you're going. But actually,
it's a form of pollution and it's one of the biggest growing types of pollution globally.

(11:30):
And not only is it growing in terms of the spread, geographic, scope, and the amount,
it’s changing in terms of type of technology and the type of lighting that we're using. It
used to be, if you remember back in the day, really orangey streetlights, for example,
where you couldn't really tell the difference between colours. So, for visual acuity for
humans was pretty poor, but you can still see. Whereas now we're getting more to the blue,

(11:53):
white end of the spectrum with the LEDs, which are great in terms of CO2 and efficiency,
but they're really bright and they're very white.And so, there's all these questions around,
how is that going to impact bats? Is it better to have a red light, an amber light or a white
light? What are the light levels that are okay for bats, if there is one at all, how does it

(12:13):
affect their behaviours, their breeding, their socializing? You know, how does it affect their
health, their physiology? So, these are all questions that we're trying to understand.
And we know already that for most species, lighting has a negative effect on bats,
and it can disrupt their feeding behaviours. It disrupts their movement throughout the landscape,
which has a knock-on effect on their feeding. And then a big project we're working on at the moment

(12:37):
is to try and understand how it affects their fitness. So, whether it affects their breeding.
So, there've been some indications that the babies of bats, it affects their growth rates
in areas where there's lots of light pollution. So, we're trying to get more understanding around
that to see any fitness level and colony level effects as well. So lighting is a big one.

(12:58):
And then of course you've got loss of habitat which affects everything, not just bats. And
historically bats, if they had the choice most of them would roost in trees. And they used to be,
as we all know, huge old growth forests across the world. But they've all sadly disappeared
over time as we've moved in and occupied it with agriculture or housing or construction of roads,

(13:19):
etc. so a loss of trees has meant that bats have had to adapt. And what's happened is bats,
they all roost in different ways. They all live in different places,
and they change that throughout the year as well. They've got a very complex life cycle. So,
a lot of bats have moved into our houses. They're moving in with us, you know, so we're taking away
their homes, they'll come and cohabit with us.And that creates its own issues in itself around

(13:44):
conflict, because not everyone, as we've touched on, wants to live alongside bats.
Yeah.So, a loss of roosting habitat,
a loss of foraging areas, so places where they can go and hunt for insects. That's meant that
historically most bats have been decline. And so that's one of the key challenges.
So, is there anything that we as individuals can do to help?

(14:04):
Sure. There's lots we can do. So, you know bats, they need food, right? So, one of the big things
in the summer, instead of cutting your lawn all the time, allow the wildflowers to grow,
allow what we consider weeds to grow. Because the more weeds, you know, the dandelions, which
we think weeds, but they're not actually wild plants, they’re wildflowers. The more of those
that are growing, there's more insects about. And the more insects there are, the more bats there

(14:27):
are. And with bats, they've got the challenge of climate change, which we haven't discussed,
and it affects all biodiversity. And it's affecting their cycles. So, bats hibernate
in the winter, and they come out of hibernation when the temperatures rise to an amount where they
think there's going to be enough food around. So, it's all linked back to their insect prey.
Well, those seasons are changing drastically and we're getting milder winters and wetter summers.

(14:51):
And so, bats are coming out of hibernation a bit earlier, and yet there might not be any food. So,
the more you can plant native plant species in your garden and not mow straight away in
early April and have all these so-called weeds around, the more insect food you're encouraging,
and therefore the more bats will be able to survive. So that's one thing.

(15:11):
And then the other thing is to think about lighting in your garden, around your property.
Do you need that 800-watt white security light. And does it have to be on every night? Probably
not. You could easily get just a small 40 watt solar one that's just triggered when someone walks
by and quickly goes off. And that's really going to help in terms of reducing the impacts on bats.

(15:32):
And then also if you have got lights, for example churches is one of my big bugbears because quite
often churches are lit up, they're illuminated as an architectural structure and it can look really,
really nice. But it means that those lights are shining straight up into the sky, which
is not a good plan in terms of all wildlife and including ourselves. There's negative

(15:52):
effects on our health from artificial lighting.So, if you have got lights making sure they're
pointing downwards to the ground, they're not, you know, shining up too far above the 90-degree
plane. So there not creating pollution. So, thinking about whether we need lights in the first
place, whether you want white lights or more red lights. So, we know that amber lights, the more

(16:13):
orangey lights are actually better for wildlife.So, trying to get away from this blue, white end
of the spectrum, lowering the intensity. So not having them so bright and making sure they're
only lighting what they need to light, they only need to light the path. They don't need
to like the whole side of your house. And those are little changes we can make. And if we all
make those changes, that will really benefit, not just bats, but all biodiversity, you know,

(16:37):
other species are also negatively affected.So, your research really does lend itself
to involving the public because people can actually become a part of this. So,
you've got this grant to do a North Somerset bat survey. What's the aim of that?
Yeah. So, we've been working with North Somerset Council and as we all know, there's big challenges

(16:57):
around housing and development and building. And so, the government's pushing for more houses
everywhere. And of course, most communities want to have nice green countryside and a bit of green
belt. And, you know, they want to be connected to nature. So, the councils and the government have
big challenges around making those decisions. How do you decide where to put the houses? You know,

(17:18):
where is best in terms of minimizing impacts on nature and biodiversity? And as I said,
bats are really good indicators for that.So, we've been working with the council
to use bats as an indicator of the health of all these different areas within the county. And so,
we thought it was a great opportunity to engage the public in that process. So,
we use bat detectors, and we have a set of bat detect kits. We have little loan centres like

(17:41):
libraries and the National Trust properties, for example, locally, they host our kit sets. And then
we have training sessions and videos online.And so, the public can just sign up to get
involved. And it shows them, and they get trained online. They can book out a kit via the website,
go out somewhere local to where they live or even in their garden. Put the
acoustic detectors out for a week and it automatically records all the bats.

(18:05):
They then upload it to an online pipeline, and it will tell them what species they’ve got, which is
quite fun. So, you can see what bats you've got in your backyard. So, it's great for people to
get engaged in conservation, but also monitoring, but also having a bit of a say in what's going
on in their local area because all those data are collated and we run some neat models and give them
all to the council, and it helps them make really robust decisions about where best to develop.

(18:30):
So, you know, we can make these recommendations, say, well, this area is really good for bats.
We've got some really rare species here, it’s a bit of a nice corridor. We shouldn't really
be letting development there. But getting people engaged in that process, to allow them to make
really well-informed decisions about where best they should develop or not throughout the county.
So, you're also doing stuff with schools as well, aren't you?

(18:53):
We are indeed. So, this year, our National Lottery funding includes a whole bunch of
funds that are going to help us work with schools. And that's a real key thing, because I think it
starts when you're young to dispel those myths. So, we're going to be engaging with a bunch of
schools around North Somerset, working with the classes, doing some sessions, developing
materials for teachers and doing some bat events where kids can, you know, design back costumes,

(19:18):
get dressed up as bats, learn about echolocation, and then also take part in the survey.
So, you know, give them some kits, they can go out, listen for bats,
they can listen to the calls and identify what bats they've got in their school grounds. So,
we're really trying to engage the younger groups as well this year in the program and use that as a
real opportunity to try to get them to embed bats into the curriculum. So were going to be holding

(19:41):
some big events this summer.So, what's next for you?
I think the sort of ultimate next stage for me would be what we're doing at county level,
working with North Somerset Council, which is helping to improve their planning and inform
their biodiversity conservation, is to be able to roll out nationally. And to do that, then we
need to go to Parliament, really, and speak to the policy makers and the change makers there.

(20:05):
So, I'm going to have to sort of get to understand a little bit about the political world and how
politicians draft policy and make those changes, so that we can then translate our research not
just from one county, but across the country.Emma, thank you so much for talking with me.
This was a podcast by the Milner Centre for Evolution at the University of Bath.

(20:29):
I'm Turi King and thank you for listening. If you have any thoughts or comments on this
or any other episodes, please contact us via our X channel @MilnerCentre.
For more information about the Milner Centre for Evolution, you can visit our website.