[INTRO]
Rae: Peter, you know just in the last couple of seasons of filming Wild Kingdom with you, one thing we’ve encountered that we don’t talk enough about is all of the darn insects that we experience when we’re out in the field. I mean some of them bite, some of them sting, some of them burrow into your skin, it can be too much!
Peter: I mean we are just food for, seems like every insect out there from ticks to mosquitoes seems like every flying insect. And then along come bats, bats are our friend devouring millions of them every night so if you hate mosquitoes you gotta love bats.
Rae: We did an episode about bats and I learned so much but ever since I’ve been making sure to kind of notice bats at dusk you know when they fly around wherever I am.
Peter: I do too. I used to teach my children when we were camping as it got dusky near the water that they could see the bats darting around, reminding them, they're finding these insects with echolocation, imagine that. Sorta like how dolphins do in the water. Incredible species, this little flying mammal that we absolutely have to save.
I’m Peter Gros, wildlife expert and educator.
Rae: And I’m wildlife ecologist Dr. Rae Wynn Grant. This is Mutual of Omaha’s Wild Kingdom The Podcast. Episode 4: Bats!
(Sonic ID)
Peter: In a recent episode of Mutual of Omaha’s Wild Kingdom Protecting the Wild Rae and I traveled to Texas. While we were there I visited a couple who built a bat preserve in their own backyard to rehabilitate bats that have been sick or injured. One night at dusk we went to the Congress Avenue bridge to release them back into the wild so they could rejoin one of the largest bat colonies in the world.
Peter: Wow here they come!
Rae: Wow oh my gosh look at that! No way!
Rae: That gathering at the bridge is a local phenomenon. Austin residents and visitors gather on the bridge every night to watch more than 1 million bats fly from the bridge to hunt for food. It was honestly like the guests were waiting for a fireworks show. But sadly, not all bat species in Texas are thriving. I had a poignant moment when I went looking for bats deep inside Gorman Cave with biologist Dr. Nate Fuller.
Nate: There should be hundreds of bats here. Maybe 10,000 bats. We should have heard them as we were walking up to the gate.
Nate: And there's nothing here right now, which is not good.
This is an old pile of bat guano. This used to be an active colony. This should be flying around and hitting us in the face and going absolutely mental right now. But nobody's home.
Rae: Nate’s an expert on the disease that is ravaging the bat population both inside Gorman Cave and across the US.
Nate: White nose syndrome is, fungal disease that first appeared in upstate New York in the winter of 2006, 2007. It affects bats while they hibernate. It's a cutaneous fungal disease. It grows on their skin, is what that means. And it eats away at their skin membrane, causing a bunch of very strange physiological responses that more or less cause bats to, wake up too often from hibernation, such that they burn through all their fat too quickly and they die. It’s wiped out a number of important hibernation sites, or dropped the population down by 90, 95% in a lot of places.
Peter: We talked to Nate, not only about what’s harming the bats, but about why bats are worth protecting. He gave us quite a story of how he got interested in bats in the first place.
[INTERVIEW RUNS]
[00:01:59] Nate: I do like to say that the bats chose me But when I was young, I was convinced I was going to be a biologist. My mom was a biologist studying fish and studying lakes and aquatic plants. And I decided I'm going to be a biologist. And I always liked the weird. I always like the unique. I like the things that that did funny stuff, the unexpected. Right. And so for me, bats happened because I was a sophomore into my junior year of undergraduate and, there was an advertisement center around the department that said, hey, this company is hiring surveyors for bats because there's lots of endangered bat surveys that are done, mostly up in the northeast. Oh, I get paid to go camping and stay up all night and catch bats. That sounds like a lot of fun. And so I signed up for it, I did it, I went camping all around Pennsylvania. We stayed up all night catching bats. And so, I had already signed up for a graduate program at a different university, and it was going to be studying mosquito ecology or entomology in some, some capacity. And, it turns out that that that program didn't work out for me. And I actually left the PhD program, which a lot of people say, don't do that. It's not good for your career or whatever. Yeah, I mean, that makes sense. But also you have to make decisions that are best for you when the time comes. And so I left that program and I went back to the bat job. And I happened to find a guy named Tom Coons at Boston University who I actually didn't know at the time because I wasn't so much a bat person, just somebody who is interested in bats, that he is the bat guy. Tom Coons was, one of the luminaries of the field. And so we are in New York State somewhere, and we randomly caught an endangered bat. And when you catch an endangered bat during these surveys, you have to put a transmitter on its back, a little radio transmitter, and then you follow it around for ten days listening for the beeps. And so that project was, you know, I go to work at 6 p.m., I come home at 6 a.m., rinse and repeat for ten days. And I like to say that the bats chose me because I got I got into bats sort of backwards in the sense I got a job and I was doing something I loved. And then I got into it. And you fall in love with them. They're they're wonderful little animals that, it's fun to do the field work. It's fun to think about their behaviors, their ecology, their physiology. And eventually I became an expert in white nose syndrome. And that became one of the biggest questions of the past 15 years. And here we are.
[00:07:14] Peter: So often we get questions about bats and why are they important. And the all the the misconceptions about how they can affect people. What would you tell people who to clear those stories up about fear of bats and diseases and that sort of thing.
[00:07:30] Nate: On a typical day, you're not going to interact with a bat. And I think in North America, there aren't really any diseases that bats carry that aren't already carried by plenty of other organisms. So they're not unique in the sense that they that they are reservoirs for disease. That's, that's just something that mammals do. And, you know, in a lot of ways people do it, too. I think that there's a place to be cautious. There are things that we don't understand going on in the ecology of these animals and the and the ecosystem around them. So, yes, they can harbor disease.
[00:09:12] Rae: You know, I have to say biologist to biologist, sometimes studying an animal, involves studying its poop. And so I'm curious about bat poop.
[00:09:22] Nate: Yeah. And I have lots of memories attached. Like, people think it smells really gross for me. It's one of the best smells in the world because it's like, oh, yeah, this, you know, it's how your smell, your, your sense of smell is attached to these deep memories. And just like some of the best times in my life were when I was waist deep in bat poop.
[00:09:37] Rae: You know, this is this is what makes you you, Nate.
[00:09:57] Nate: So, yes. Collectively we call it guano. Guano is actually a mixture of urine and feces. So there's a guano pile underneath where the bats are that has urine, which is the nitrogenous liquid waste. And then there's feces, which is the solid waste. Those fall and they mix. And the benefits of it are multilevel. So you've got, cave ecosystems that are fully dependent on that poop a lot of the times. So you see these huge insect communities that are just fully based on them processing bat guano. There's also, bat guano is, very well known and very effective fertilizer. It has lots it's very rich in nitrogen people actually still commercially minor in Texas with.
[00:10:43] Rae: It's an industry. There's an industry around mining guano.
[00:10:47] Nate: I'm not kidding when I say this, Rae. There are, guano rustlers who will clandestinely go into caves and vacuum it up and run off under the cover of darkness like, steal guano out of caves, because you can sell it for a good amount of money.
[00:11:03] Peter: Yeah.
[00:11:04] Rae: There's a bat guano black market. My my, my. Say, this is why we really got you on the podcast. Just to give us the real deal. Is that the criminal behavior around bat poop?
[00:11:17] Nate: Yeah. I hope I don't get my my thumbs broken for saying something like that.
[Music cue]
Rae: Nate, we are geeking out about bats and we're talking to you about bats. And we're calling you the bat guy. And we had a bat episode. But, you know, bats are not one species, right? Tell us about the diversity within bats. And, you know, maybe some of the extremes when we talk about different species.
[00:11:41] Nate: This is one of my favorite questions of all time.
[00:11:44] Rae: Yeah.
[00:11:44] Nate: Really good. I really like this. It's one of those where I wish I wish there was a video component to this because we could really I could really illustrate what it looks like. But bats come in all shapes and sizes. They're they're wildly diverse. And we think it has a lot to do with the fact that they evolved about 55 million years ago when there was this open ecosystem out there, which is nocturnal aerial insectivores. And, so, like, there's nothing flying, back in prehistory, there's nothing flying around at night, that's eating things that are, that are in the sky. And so bats found a way to exploit that niche. And from there they diversified into all kinds of different things.
[00:12:24] Rae: Ooh they’re smarty pants
[00:12:25] Nate: Yeah, the smallest bat out there is a bumblebee bat, which if you Google it, I don't know. It's about the size of the, of the, of the distal portion of your thumb, that last joint of your thumb. I think they weigh about a gram. They're really tiny. They're the largest bat is the Malaysian fruit bat, which has a wingspan that's six feet long, which is as wide as how, as wide as my arms.
[00:12:48] Rae: You are kidding. Not six feet??
[00:12:51] Nate: Six feet. Yeah, I think they're they're probably a little a little shorter wingspan than Peter is tall, but it would be a pretty close race right there.
[00:12:59] Rae: Oh my goodness. So from, from thumbnail size to six feet. Yeah.
[00:13:05] Nate: And those are the flying foxes right. And those are, those are fruit bats. There's there's bats that will display. They have like a mohawk of a they just have a weird patch of hair on their heads and it turns into a mohawk that they use to display to females. There's bats that are pure white that, make tents. They go under leaves and they chew the leaves along the rib so that the leaf falls down. And they make these temporary roosts that are called tents. There are bats that eat fish. There are bats that eat frogs.
[00:13:35] Rae: Bats that’s go fishing?
[00:13:36] Nate: Yes, but instead of using their mouth, they drag their feet through the water. And you see these, these animals. So the bats that you saw, the cave in Texas, those are also a myotis species. And that's a very common. It's a very diverse genus of bat. And they all kind of have the same body form. But this fishing myotis has huge grappling hook looking feet. So evolution has pushed them such that they drag their feet across the water and they'll scoop up fish that are hanging on the surface. Then they pull it up to their mouth and they eat it. Really fascinating. Let's see what else is out there. There are. There's spotted bats. There's bats with really big ears. There's bats that that can hover. There's nectar feeding bats that basically are nighttime hummingbirds. I mean, there are I'm going to say I'm going to say a nonspecific number, but I say it for a reason. There are almost 1500 species of bat in the world, which is the second most diverse order of mammals, second to rodents. And I say that's nonspecific. I say almost 1500 because basically every day it changes. There are people discovering new bats all the time, and eventually when that number passes, 1500 will throw a party and, you know, move on because and then five days, it's going to be, you know 1510.
[00:14:52] Rae: This is a challenge actually for Wild Kingdom because we care a lot about bats and we care a lot about species diversity. So we might have 1500 episodes in our future, all on a different kind of language.
[00:15:04] Peter: And how many would we find in just in the United States alone?
[00:15:08] Nate: In the United States, I believe there are 47.
[00:16:59] Rae: Peter and I have some bat cave experience now, thanks to you and your colleagues in Texas and the episode that we filmed. And you have been going into bat caves for years now. I mean, it's how you study these bats. What was different about the bat cave you and I went into and what we saw there versus some of the other caves that you've been in?
[00:17:29] Nate: The biggest thing about that cave, Gorman Cave in in central Texas is that. I had been in that cave before when it was absolutely packed full of animals. And you go into the into the the main room where the maternity roost is supposed to be, and the bats are immediately flying around and the the wing flap, their wing flaps and the way they're moving air inside of that closed room. The only way you can really describe it is thunderous. They are just it's really an experience. And I. I'm very sad that you didn't get to see it, but, that's really what struck me is that there should have been huge clusters of animals in there and there, and there really were not and I had unfortunately, that is similar experience when you're a white nose syndrome researcher like me. That experience is pretty common these days, where you go into a cave and you expect to see a bunch of bats, and there are no there are no bats, or you go in there and there are a bunch of dead bats on the floor, which is arguably a lot worse than seeing no bats, because if you don't see them, then you can hope that they're still alive somewhere. So I was very struck by that, and I think it came through in the episode quite a bit.
[00:19:03] Nate: And I'll tell you this, that we we went back to that site later, and there were more bats than there were when we saw them. I don't know, there's like maybe 3 or 400 animals that that came out.
[00:20:39] Rae: That's a big difference. That's a big difference.
[00:20:41] Nate: It's a it's a big difference. But at the same time, five years ago, that cave had 18,000 animals in it. If you go down exactly, it's gone. So if you go down to 500, that's not a natural variation. That's that's like that's something that bats can't even really recover from in our lifetime. Maybe the populations will recover. I don't know, but it sounds like white nose isn't getting better.
[00:21:07] Peter: Nate, is there a possibility that there's a way to treat white nose syndrome in the near future?
Nate It's, it's possible. There are. There are treatments available. There are people who have who have done a lot of work on, on developing, evaluating and testing treatments on bats, both in the lab and in the wild. There's, work that you can do where you're, spraying a volatile organic compound that treats both the bats and the walls of the of the site. There's, a vaccine in development that has a little bit of promise to it. But in general, all of these things. Yes, maybe they can work. And, I'm very encouraged by some of the results that we see But at the same time, It's really hard to figure out how you're going to distribute this treatment at scale to a point where you've treated, I don't know, 95, 98% of the population. And that's what you need to do to help slow down white nose syndrome. It will definitely take time, and it will definitely take patience. And unfortunately, it's very hard to do that when, there are now discussions of of listing some bats as endangered species because of white nose syndrome.
[Music transition]
Rae: Now, Nate. Okay, bats are nocturnal, right? And human beings are diurnal. Right. So we don't interact with bats very much just because we are out and about at different times of the day. And so I it's leading me to wonder, can you tell us a little bit more about where bats are found? I mean, let's take the United States, for example. And one reason I'm asking is because I lived in New York City for quite a while, and this was probably about ten years ago. I was in midtown Manhattan, and it was like dusk, and I was headed down into the subway and it was busy. It was rush hour, and I was just going fast down the stairs. And there was what looked like a crumpled up leaf on the steps of the subway. And I thought to myself, I don't know if that's a leaf. And I crouched down and there are people yelling at me because I was going slow, and I got a really good look and it was a bat. So when it comes to the U.S., I mean, where can people find bats? Is it everywhere?
Nate: Yes, it actually is.
Rae: Easy answer.
Nate: I have a similar story where I was in graduate school in Boston. I was, you know, I could see Fenway Park from my office. And every year, in the spring I would get a call from somebody saying there's a bat on the sidewalk outside, and I would be like, okay, well, I will, because I have rabies shots. I know how to handle a bat and all that kind of stuff. So I would run downstairs, I grab the bat, I put it in a bag, and I set it up to make sure it's doing okay. You know, offer it some water, maybe offer it a mealworm or two, and then by the time night comes around, you take it out and you let it go and it flies away and it goes and does its thing. So you probably ran into a big brown bat, which are probably some of the most cosmopolitan bats that we have. They live actually everywhere.
Rae: Okay. So they can be New Yorkers too.
Nate: They can be. Yeah. There's of course, different diversity hotspots where you'll find more bats and fewer bats. So in the northeast there's maybe about nine species of bats that you can encounter. Whereas when you go down to Texas or Arizona, you're talking about 20 to 30 species of bats that you can encounter. And it has to do with the environment that's available, the different ecosystems that are intersecting. I mean, Texas, for example, we’ll just say this. You've got the eastern swamp species that are coming in, you've got the western mountain species that are coming in, you've got southern Mexican species and northern Great Plains species. You have this cool nexus of habitats, which means that you have a cool nexus of, biodiversity. And it's not just in bats, but of course, you know, that's what we're here talking about. So basically, wherever you are, there are bats.
Peter: Nate, it does sound like they're incredibly adaptable. What do you think about climate change? Is that something you think over time, you can hypothesize they might adapt to?
Nate: Yeah. Oh, boy, that's a big one. And I mean, it always is. The big question can can bats adapt to climate change. And there's some there's some interesting ways to think about it in terms of. So hibernation for example, the temperature inside of a cave sort of reflects the mean annual surface temperature of the environment outside the cave. So now you have a warmer cave when climate change really kind of takes hold. And I've had a lot of people say, well, if a cave is warm, isn't that good for bats? Because aren’t they avoiding the cold, right? Yeah, exactly. But actually you need to think about it in the reverse, because the reason why bats hibernate, the reason why bats go in caves where it's a stable temperature is because they're trying to stay cold, because if they can drop their body temperature down to, 50°F, that means they save more energy. If the average temperature inside that cave is now 60, they're burning ten more degrees worth of of body temperature in calories over time. So climate change makes hibernation harder to survive for a lot of animals, because maybe the insect populations don't respond in the same way. And bats will emerge from hibernation too early and not have the insects they need to to survive on. Same with birds coming back too early when they migrate.
Rae: Okay, so I gotta ask now if someone encounters a bat and, you know, maybe we can talk about different scenarios, but what should they do? If there's a bat in your home, what should you do? And then if you find a bat, if you know, just out in the world, maybe injured or something, what do you advise people do.
Nate: Typically, if you find a bat in the daytime on the ground acting strange, it could be rabid and you don't want to interact with it. So if you find a bat outside, just don't mess with it. It'll either be fine or it's sick and you don't need to mess with it in either case. If there's a bat in your house, the best thing you can do is isolate that bat in a room and open up all the windows and it'll find its way out. Typically, they find their way out fairly quickly. If it's in a spot where you can't do that, put on some heavy gloves. Get a shoe box. Try to scoop it up in the shoe box. Put the lid on. Take it outside, put it on the ground. Open it up and the bat can find its way out. Gloves are important. Don't touch the animal barehanded. If it bites you, go to the doctor.
Peter: Now, for people like me that like having bats around. I've read quite a bit about bat houses. What do you think about those? Do you recommend people to put those in there?
Nate: Yeah. So a bat house is just a, probably it's made out of plywood. People are now making them out of composite materials. They're, just a roosting structure that are manmade. That, bats can can hang on. It's like a duck box or a bluebird box or any of that kind of stuff. If the bat box is well-made and well placed, they can provide good habitat for bats. On the opposite side of that, if a bat box is poorly made and put in the wrong spot, it may not be inhabited by bats, or at worst, it could actually harm bats by being too hot and, that can eventually kill pups or cause bats. Bats are really good at getting cold. You know, as we talked about with hibernation, bats are not good at getting hot. So once they get too warm, then, they're pretty close to dying very quickly. So we, we try not to overheat them. So bat box needs to be set up such that it can it can, it can be warm but not too warm. And so if you're in the northeast, for example, you want to paint the box black and actually put it out in the middle of a field with south facing exposure. If you are in the south, you want to paint it more of a beige color and put it somewhere that it maybe gets some afternoon shade.
Rae: This is this is leading me to think about something else. And again, it relates back to the really exciting episode. We filmed season one for Wild Kingdom Protecting the Wild. We found bats not in bat boxes, not in caves, but under a bridge. In the middle of Austin, Texas.
Congress Avenue Bridge is a really special place. It's the largest urban bat colony in the world. This is the place where bats and humans have worn their action. Them anywhere on the planet. That's a wonderful, example to the rest of the world. How humans and wildlife can coexist.
Nate: The bridge in Austin is one of the biggest success stories in bat conservation, where when the bats first moved in, people were aghast. They wanted them out of there. They wanted them exterminated or removed or whatever. And through lots of work, by, really dedicated bat biologists, they managed to keep the population there and convinced the city that they should live alongside the bats. And now it is one of the hottest tourism spots in the city, and it brings $10 million a year to Austin.
Peter: What a treat for us. Thanks, Nate.
Nate: I really appreciate it. I want to tell you guys that this was an absolute highlight of my career. I am never going to forget the experience I had with you in the cave during the whole process. It was so much fun. And this is a whole lot of fun too.
With white nose syndrome and threats to their environments bats are currently experiencing a massive die off. People like Nate Fuller are helping to learn more about this threat to bat populations in North America. Many people think bats are scary and dangerous but like you heard today bats are an important part of our environment. Maintaining healthy bat populations and educating the public are key to helping these threatened species. If we protect wildlife and the environment today, we can ensure magical moments in the wild kingdom for future generations.
Rae: Join us next week when we speak with Nadya Seal about some incredible islands just off the coast of California.
Nadya: You know sometimes you can get caught up with the doom and gloom of media headlines you know but it’s so important to know that you have lights at the end of the tunnel, know that you can move the needle in the right direction. It’s one of those things where you see a species that might be going down and say no we can reverse that. We’ve done it before we can do it again.
Rae: That’s next time on Mutual of Omaha’s Wild Kingdom The Podcast.
[OUTRO]
Mutual of Omaha’s Wild Kingdom The Podcast is a production of Pineapple Street Studios and Mutual of Omaha.
Our Senior Producer is Stephen Key
Producers are Xandra Ellin and Jenny Van Soelen
Associate Producer is Lisa Cerda.
Editor is Darby Maloney.
Executive Producers are Bari Finkel, Gabrielle Lewis, and Jen Wulf.
Pineapple’s Head of Sound & Engineering is Raj Makhija. Senior Audio Engineers are Marina Paiz, Davy Sumner, Javi Cruces, and Pedro Alvira. Additional engineering by Rob Miller and Jason Richards.
This Episode was mixed by Davy Sumner.
Production Music courtesy of Epidemic Sound and Hearst Media Production Group.
Episode Clips courtesy of Hearst Media Production Group.
Fact checking by Justine Daum.
Marketing and Promotion by Emily Poeschl.
This podcast is hosted by me, Dr. Rae Wynn Grant
And me, Peter Gros.
Special thanks to Katelyn Williams, Sophie Radmilovich, and Stephanie Diaz.
Today’s episode is based on the Mutual of Omaha’s Wild Kingdom series created by Don Meier.
Our next episode will be out in a week. Make sure to listen on the Audacy app, or wherever you get your podcasts.