Transcript
The Night Flyer: How Bats sPOOkily Revive Forests | Terrestrials Podcast
From Radiolab · Episode page · Watch on YouTube
· 26 min · 4,203 words · 98 timestamped sections
This is the full, timestamped transcript of "The Night Flyer: How Bats sPOOkily Revive Forests | Terrestrials Podcast", an episode of Radiolab published November 5, 2025 (26 min, about 4,203 words). It mentions 81 people, works and ideas, including Stenoderma, Terrestrials, Batman, Count Dracula, echolocation.
What this episode is about
The content explores the vital role that bats play in ecosystems, focusing on their ability to rejuvenate forests and maintain biodiversity through their unique behaviors. Featuring insights from a bat researcher, the narrative highlights the intriguing characteristics of these nocturnal creatures and their often-overlooked significance in environmental health.
Key takeaways
- Bats: More puppy than pest, bridging gaps from Dracula myths to ecosystem superheroes.
- Stenoderma bats likened to adorable Chihuahuas repair environments post-hurricanes—nature's gentle eccentricities.
- Bats scoop insects mid-flight with wings, proving chaos is just gravity's dance partner.
- Borikua Batman's odyssey: Venturing fearlessly into unknown caverns birthed lifelong winged fascination.
- Bat wings: Translucent canvases beneath twilight, shattering illusions of flightless rodents.
What is discussed, and when
- – 5:00: Batman, Stenoderma, big brown bats, Borikqua
- – 10:00: Alexis Wilkins, anti-coagulant, Association, Batman
- – 15:00: Stenoderma, 150 mph, alcohol, Alexis Wilkins
- – 20:00: squirrels, Stenoderma, carbon dioxide, fertilizer
- – 25:00: echolocation, Anura fistula, Bewitched, Cliff Stanley
- – 26:21: American Museum of Natural History, Anna Gonzalez, Burman Tonic, Conserv Puerto Rico
Notable quotes from "The Night Flyer: How Bats sPOOkily Revive Forests | Terrestrials Podcast"
All right. [clears throat] You're listening to Radio Lab.
about Radio Lab · atBest. You got it. Terrestrials is a show where we uncover the stranges waiting right here on Earth. I am your host, Sula Miller, joined as always by my song bud.
about Terrestrials · atBut the star of today's show is Stenoderma.
about Stenoderma · atUp between the trees. The bat is all tangled up in the threads until a scientist named Wilkins reaches in with a gloved hand and gently untangles its furry little body.
about Alexis Wilkins · atThey can see quite well, but on top of that, they're using echolocation.
about echolocation · atThe American Museum of History holds more bat specimens than the majority of collections in the world.
about American Museum of Natural History · atPath. And one of the most powerful hurricanes ever to make landfall in recorded human history was Hurricane Maria, which hit Puerto Rico in 2017.
about Hurricane Maria · atEating bats like Stenoderma, they're responsible for up to 95% of the regrowth of tropical forests after destructive events like hurricanes. 95%.
about tropical forests · at
Who and what is mentioned in this episode?
People
- Batman — Person · 5 mentions · first at
And here to help me tell the tale is Batman because I study bats.
- Count Dracula — Person · 3 mentions · first at
Towards its forehead. It has sharp fangs, and with its wings stretched out, it looks like Dracula.
- Alexis Wilkins — Person · 2 mentions · first at
- Bruce Wayne — Person · 1 mention · first at
Okay. It's not undercover superhero Bruce Wayne. It's actually Angelo Sto Centenno, a Puerto Rican scientist now living in New York City.
- Wilkins Ottero — Person · 1 mention · first at
And bat scientist Wilkins Ottero tells me that normal hurricanes have always played an important role in the ecosystems down here.
- Sophie — Person · 1 mention · first at
Hi, my name is Sophie and I feel zone. My question is, why is there so many species of bats?
- Cliff Stanley — Person · 1 mention · first at
Hi, my name is Stanley and I'm 5 years old. Do different bats make different sounds?
- Rapunzel — Person · 1 mention · first at
Like walking around. I'm not going to tell you that cuz I'm nice, but I would name that bat the Rapunzel tongue bat. But it's not named that. is actually named the tube lipped…
- Lula Miller — Person · 1 mention · first at
Nectarbat aka Anura fistula. anyway, that's it. Terrestrials was created by me, Lulu Miller with WNYC Studios.
- Anna Gonzalez — Person · 1 mention · first at
This episode was reported and produced by Anna Gonzalez. did I mention I am the president of her fang club? Her Fang Club with beautiful sound design by Mera Batwintonic. actually Burman Tonic. Our executive producer is.
- Mera Batwintonic — Person · 1 mention · first at
The president of her fang club? Her Fang Club with beautiful sound design by Mera Batwintonic. actually Burman Tonic. Our executive producer is Sarah Samback. Our team also…
- Burman Tonic — Person · 1 mention · first at
Fang Club with beautiful sound design by Mera Batwintonic. actually Burman Tonic. Our executive producer is Sarah Samback. Our team also includes Ellen Gaffinsky, Tanya Chala, and Joe. Factecking by Emily Kger.
- Sarah Samback — Person · 1 mention · first at
Design by Mera Batwintonic. actually Burman Tonic. Our executive producer is Sarah Samback. Our team also includes Ellen Gaffinsky, Tanya Chala, and Joe. Factecking by Emily Kger.
- Ellen Gaffinsky — Person · 1 mention · first at
Burman Tonic. Our executive producer is Sarah Samback. Our team also includes Ellen Gaffinsky, Tanya Chala, and Joe. Factecking by Emily Kger.
- Tanya Chala — Person · 1 mention · first at
Burman Tonic. Our executive producer is Sarah Samback. Our team also includes Ellen Gaffinsky, Tanya Chala, and Joe. Factecking by Emily Kger.
- Emily Kger — Person · 1 mention · first at
Sarah Samback. Our team also includes Ellen Gaffinsky, Tanya Chala, and Joe. Factecking by Emily Kger.
- Zach Gdder Cohen — Person · 1 mention · first at
Also, big fangs to Zach Gdder Cohen.
- Angelo Sto Centenno — Person · 1 mention
- Jack Alan — Person · 1 mention
- Judge Judy — Person · 1 mention
Companies & orgs
- Terrestrials — Company · 5 mentions · first at
- American Museum of Natural History — Company · 2 mentions · first at
- Radio Lab — Company · 1 mention · first at
- Bewitched — Company · 1 mention · first at
Going. The nose is actually quite movable. You can see them kind of like almost like digging like bewitched. Oh, like the little nose scrunch from Bewitched.
- WNYC Studios — Company · 1 mention · first at
Nectarbat aka Anura fistula. anyway, that's it. Terrestrials was created by me, Lulu Miller with WNYC Studios.
- Conserv Puerto Rico — Company · 1 mention · first at
Special thanks to the American Museum of Natural History and Angeloto and Conserv Puerto Rico. Gracias. support for terrestrials is provided by the Simons Foundation, the Arthur Vining Davis Foundations, and the John.
- WNYC — Company · 1 mention
Products & tech
- headlamp — Product · 1 mention · first at
Darkness of the forest. Huh? Do I hear you actually going in there? Mhm. Sounds scary. Don't worry, I have a headlamp and a whole team of Batman's Anna. I'm tiptoeing through…
- gloved hand — Product · 1 mention · first at
Tangled up in the threads until a scientist named Wilkins reaches in with a gloved hand and gently untangles its furry little body.
- energy drink — Product · 1 mention · first at
No, this is my drink. This is my energy drink. I'm just kidding.
Concepts & topics
- Stenoderma — Concept · 8 mentions · first at
- echolocation — Concept · 3 mentions · first at
- mosquito — Concept · 2 mentions · first at
Which explains why bat flight patterns look so chaotic to us on the ground cuz every time they spot a mosquito or a moth in the air and shovel it into their mouths, their wings…
- Hurricane Maria — Concept · 2 mentions · first at
- tropical forests — Concept · 2 mentions · first at
- squirrels — Concept · 2 mentions · first at
As we've learned on terrestrials, squirrels will sometimes help plant trees by forgetting where they buried their nuts. But there are no squirrels in the tropical forest of Puerto Rico.
- Borikqua — Concept · 1 mention · first at
And this Borikqua Batman grew up fascinated by bats. As a kid, he would hear them rustling in the trees outside of his bedroom window. And he wanted to find out what they were doing out there.
- Jamaican fruit bat — Concept · 1 mention · first at
Had this little cavern. And inside that cavern, there was a roost of this Jamaican fruit bat. I would go in there with a stick and just try to poke him and just to make him fly out.
- free tail bats — Concept · 1 mention · first at
We got red bats and we got free tail bats, big brown bats, horseshoe bats, and pollinator bats with long tongues like hummingbirds.
- red bats — Concept · 1 mention · first at
We got red bats and we got free tail bats, big brown bats, horseshoe bats, and pollinator bats with long tongues like hummingbirds.
- big brown bats — Concept · 1 mention · first at
We got red bats and we got free tail bats, big brown bats, horseshoe bats, and pollinator bats with long tongues like hummingbirds.
- horseshoe bats — Concept · 1 mention · first at
We got red bats and we got free tail bats, big brown bats, horseshoe bats, and pollinator bats with long tongues like hummingbirds.
- pollinator bats — Concept · 1 mention · first at
We got red bats and we got free tail bats, big brown bats, horseshoe bats, and pollinator bats with long tongues like hummingbirds.
- hummingbirds — Concept · 1 mention · first at
Bats, big brown bats, horseshoe bats, and pollinator bats with long tongues like hummingbirds.
- leaf nose bats — Concept · 1 mention · first at
And we got little motus bats, leaf nose bats, flying foxes look like puppies, and they're beautiful. They look like a little Chihuahua.
- flying foxes — Concept · 1 mention · first at
And we got little motus bats, leaf nose bats, flying foxes look like puppies, and they're beautiful. They look like a little Chihuahua.
- Chihuahua — Concept · 1 mention · first at
Bats, flying foxes look like puppies, and they're beautiful. They look like a little Chihuahua.
- True vampire bat — Concept · 1 mention · first at
True vampire bat. They really look crazy. But only three species of bats drink blood. The rest of the over 1,000 species are insectovores.
- anti-coagulant — Concept · 1 mention · first at
Vampire bats only drink blood. The saliva is anti-coagulant. Pigs and cows, dear birds and goats.
- Regurgitation — Concept · 1 mention · first at
Regurgitation. They hang together in groups.
- Association — Concept · 1 mention · first at
Association. They've been roaming the earth for millions of years, longer than our Dracula myths and fears.
- caribou — Concept · 1 mention · first at
We're walking down a long hallway past taxiderermy coyotes and caribou heads looking for the right cabinet of bats.
- alcohol — Concept · 1 mention · first at
So these are basically specimens that have been collected and their entire body is preserved in alcohol.
- hurakang — Concept · 1 mention · first at
In their burrows waiting for the storms to pass. The word hurricane actually comes from the word hurakang, meaning the tyino god of storms and destruction.
- succession — Concept · 1 mention · first at
There is a succession of the forest where the biggest trees fall and allow the others to grow.
- ecological balance — Concept · 1 mention · first at
You'd probably call it an ecological balance. The problem is that the hurricanes that we are seeing more and more of today are fueled by climate change, which warms the oceans.
- Iguanas — Concept · 1 mention · first at
Before Maria, the forest of Puerto Rico were lush and dark. Iguanas and little crusted anol lizards hid in tangles of leafy tree branches. The song of bird and kis filled the moist air. But Maria came with winds over 150 mph.
- 150 mph — Concept · 1 mention · first at
Leafy tree branches. The song of bird and kis filled the moist air. But Maria came with winds over 150 mph.
- rainforests — Concept · 1 mention · first at
Entire rainforests were chopped down by the winds and rain. The floods carried away birds, lizards, frogs, cows, and horses. And even caves were flooded, carrying away bats.
- fertilizer — Concept · 1 mention · first at
Certain seeds just enough to get them ready to grow. Plus, bat poop is an amazing fertilizer for the soil.
- carbon dioxide — Concept · 1 mention · first at
Tropical forests like the ones in Puerto Rico clean the Earth's air. They pull out huge amounts of carbon dioxide from the air, which makes it easier for us humans to breathe and slows down the warming effects of climate change.
- landslides — Concept · 1 mention · first at
Rely on the trees there for habitat. And after disasters like hurricanes and landslides, and even when human beings chop down trees for roads and buildings, it is the fruit…
- Anura fistula — Concept · 1 mention · first at
Tongue bat. But it's not named that. is actually named the tube lipped nectarbat aka Anura fistula. anyway, that's it. Terrestrials was created by me, Lulu Miller with WNYC Studios.
- anole lizards — Concept · 1 mention
- caves — Concept · 1 mention
- doctor birds — Concept · 1 mention
- frogs — Concept · 1 mention
- goats — Concept · 1 mention
- guano — Concept · 1 mention
- moth — Concept · 1 mention
Places & events
- Dorado — Place · 1 mention · first at
Anna. I'm tiptoeing through the woods of a small farm, a fina in the town of Dorado, Puerto Rico. The chickens and dogs and horses have all gone to bed, and now is the time when the creatures of the night take over.
- fina — Place · 1 mention
- Rio — Place · 1 mention
Sponsors
- Simons Foundation — Sponsor · 1 mention · first at
Conserv Puerto Rico. Gracias. support for terrestrials is provided by the Simons Foundation, the Arthur Vining Davis Foundations, and the John Tumbleton Foundation. Fang you.
- John Tumbleton Foundation — Sponsor · 1 mention · first at
Terrestrials is provided by the Simons Foundation, the Arthur Vining Davis Foundations, and the John Tumbleton Foundation. Fang you.
- Arthur Vining Davis Foundations — Sponsor · 1 mention
Full transcript with timestamps
Oh, wait. You're listen. Okay. All right. Okay. All right. [clears throat] You're listening to Radio Lab.
Radio Lab from WNY. 3 2 1. Imagine twilight descends and you open your mouth to let out high-pitched pulses that guide you as you're
exploring the world. From your back, you sprout massive wings, but not like a bird, more like,
come on, dragon, a dragon, and you spend the night prowling for unsuspecting victims. But as the sun begins to rise, you rush home
straight to your wings and wrap them around your body until you fall asleep upside down. You have become
a bat. Now is the part where I make you sing the theme song with me. Terrestrials. Terrestrials. We are not the worst. We are the
bestials. Best. You got it. Terrestrials is a show where we uncover the stranges waiting right here on Earth. I am your host, Sula Miller, joined as always by my song bud.
Bat to the bone Alan and my producer bud. What's up, Anna? Uh, and you are bringing us a spooky story about this spooky creature who flies just out of sight of humans in the dark night stealthily. making the world a better place. Uh-huh. And here to help me tell the tale is Batman
because I study bats. Okay. It's not undercover superhero Bruce Wayne. It's actually Angelo Sto Centenno, a Puerto Rican scientist now living in New York City. And he's not the Batman, but as a guy who catches bats for a living, has studied bats for over 20 years, and has an arm full of bat tattoos.
That is true. I'm going to call him a Batman. You got to do what you got to do.
And this Borikqua Batman grew up fascinated by bats. As a kid, he would hear them rustling in the trees outside of his bedroom window. And he wanted to find out what they were doing out there under the cover of darkness. So, he started poking around for bats. Literally,
there was a little creek that had this little cavern. And inside that cavern, there was a roost of this Jamaican fruit bat. I would go in there with a stick and just try to poke him and just to make him fly out. Wait, but wasn't that like scary? Were you scared at all?
No. Many people may be afraid of the dark. I'm I'm definitely not. And now as an adult, Angelo studies all kinds of bats.
We got red bats and we got free tail bats, big brown bats, horseshoe bats, and pollinator bats with long tongues like hummingbirds.
And we got little motus bats, leaf nose bats, flying foxes look like puppies, and they're beautiful. They look like a little Chihuahua.
But the star of today's show is Stenoderma. Stenoderma means thin skinned. It's a bat with somewhat see-through wings, short reddish fur, big pointy ears that almost look like devil horns. It has beady eyes and a long pointy pig snout that stretches up towards its forehead. It has sharp fangs, and with its wings stretched out, it looks like Dracula.
Lerma is maybe not for everybody, but I think it's it's actually quite a cute bat.
Hm. Agree to disagree, Angelo. But he tells me that behind that creepy face, Stenoderma holds something gentler and something crucial for humanity. The ability to repair the planet after some of the most powerful natural disasters ever. Hurricanes, bats.
Mhm. And we'll get there, but first we need to wade deep, deep into the darkness of the forest. Huh? Do I hear you actually going in there? Mhm. Sounds scary. Don't worry, I have a headlamp and a whole team of Batman's
Anna. I'm tiptoeing through the woods of a small farm, a fina in the town of Dorado, Puerto Rico. The chickens and dogs and horses have all gone to bed, and now is the time when the creatures of the night take over. Flying over our heads are dozens of winged silhouettes of bats crossing the sky lit by the moon between trees. The Batman I'm here with are bat scientists and pat enthusiasts.
No, that's what they and they keep telling me not to be scared. But I can't help but feel a little freaked out as they swoop around the trees over us in their chaotic way. Cuz I've never really seen a bat. Not up close. I've been told to stay away from them. I've only heard bad things like they're rats with wings. They drink blood. They want to bite me. And it feels like these ones might fly right into my head.
Yeah. Yeah. Yeah. But then at the bottom of the hill, yes, we catch one in a huge net that these Batman have set up between the trees. The bat is all tangled up in the threads until a scientist named Wilkins reaches in with a gloved hand and gently untangles its furry little body.
This is an insect eating bat. A big brown bat. This species may be called big brown bat, but it fits in the palm of his hand. And then he invites me to touch it. It is so soft.
And touching the wing. Up close, I see how adorable it is. So delicate. This creature that's the only mammal that flies with its perky ears and a fuzzy little body.
It's not like a rat at all. It looks like a little dog. It's a very beautiful bat. Not only does it look like a dog, it is actually more closely related to dogs than rats. Huh. And like a dog.
Bats are very heavy animals. If they stop beating their wings, they'll plop down.
Which explains why bat flight patterns look so chaotic to us on the ground cuz every time they spot a mosquito or a moth in the air and shovel it into their mouths, their wings actually stop flapping and they drop down in the air and then start flying again in the blink of an eye. Fat myth busting.
Also, did I hear that right? They're using their wings as they fly to catch the bugs. They're not just using their tongue like a little like a frog.
Mhm. They pick up the insects with their wings and they bring it to the mouth. They're just like shoveling them in as they like a wing spoon. But how are bats even finding these insects to eat? I thought they like couldn't see at all. They can see quite well, but on top of that, they're using echolocation.
Echolocation. Bats use their voices to create a map of the world. Because what happens when you yell into a big cavernous space like an empty room or a stairwell, you get an echo. Echo.
That's the sound of the actual sound waves of your voice bouncing back to your ears. Bats do that all the time through those high-pitched screeches they make.
It's more like pulses. And each pulse goes out, bouncing off of things around them like tree trunks and leaves and even insects, allowing them to hear where to fly next. And it's how bats have been able to evolve into creatures of the night. Most birds can't fly in the dark because their eyes need light to see. But bats rule the skies while the little birdies are all sleeping. Okay, but Anna, can I interrupt because
Yes, Lulu, this is our spooky episode. What about the bats that like drink [sighs] blood?
I knew you were going to ask about that. Thirsty bats. Is that myth real at all?
Okay, yes, they are real. True vampire bat. They really look crazy. But only three species of bats drink blood. The rest of the over 1,000 species are insectovores.
I want to eat your bugs or fruit eating bats. I want to drink your fruit juice.
Totally fascinating. I still want to know about blood sucking bats, though. All right, here is everything you want to know about vampire bats in 30 seconds or less in a song.
Vampire bats only drink blood. The saliva is anti-coagulant. Pigs and cows, dear birds and goats.
They search for body heat with their nose. They chop through skin with razor sharp teeth. Their tongue laps up the blood. That's all they eat.
And to share food, they puke. Regurgitation. They hang together in groups. Association. They've been roaming the earth for millions of years,
longer than our Dracula myths and fears. And they can run on the ground on all fours.
They don't eat bugs or fruit. They're singing. Latin for blood and devour. I love it. Are you good? My thirst for blood is quenched. Great. Now we're finally going to meet a fruit eating batam that holds the key to regenerating forests after massive hurricanes. A key that lies deep within the bowels of a hollowed museum and deep within the bowels of the bat itself. Huh? I'll explain right after the break.
Terrestrials is back. I'm producer Bud Anna on a quest to find the elusive that can supposedly help repair an entire ecosystem after fierce hurricanes. But so far, on my night hike through the woods of Puerto Rico, we've come up empty-handed. Luckily, Angelo knows where I can see one up close and personal.
The American Museum of History holds more bat specimens than the majority of collections in the world.
Angelo works here in the museum, and he's leading me away from the tourists and the giant whale and into the secret back corridors. This entire hallway has dozens and dozens of cabinets that are all full of bats.
We're walking down a long hallway past taxiderermy coyotes and caribou heads looking for the right cabinet of bats.
There's stenoderma rufam rufam here. Angelo unlocks it. Let me show you the creepy thing here.
It looks like a jar of dead things. No, this is my drink. This is my energy drink. I'm just kidding.
This is not an energy drink. It is in fact a jar of things that look like pickles but are actually pickled bats.
So these are basically specimens that have been collected and their entire body is preserved in alcohol.
He opens up the jar and pulls out three wet, stinky dead bats. It looks like a bat zombie. Angelo, it is creeping me out.
I love it. I love this stuff. Angelo says stoodma are some of the most mysterious bats out there. They spend their lives hiding in the upper canopies of trees where the forests are so thick light from the moon can't penetrate through the leaves. And they're on the prowl for fruit. As much juicy fruit as they can snarf. And then they fly back home, hang upside down, and wrap themselves up in their little winged sleeping bags. All without ever getting caught in a human trap. But the true wonder of the stenoderma only reveals itself after one of the scariest things of all. A big powerful hurricane.
Yeah. Living on an island, storms and hurricanes are a natural occurrence. The trees hold themselves down with their roots and people hide away safe and warm in their homes. The animals hunker down in their burrows waiting for the storms to pass. The word hurricane actually comes from the word hurakang, meaning the tyino god of storms and destruction. And bat scientist Wilkins Ottero tells me that normal hurricanes have always played an important role in the ecosystems down here.
There is a succession of the forest where the biggest trees fall and allow the others to grow.
You'd probably call it an ecological balance. The problem is that the hurricanes that we are seeing more and more of today are fueled by climate change, which warms the oceans and makes the winds and rains more intense than anything human beings have seen before.
It was a monster. What was happening? When a monster hurricane swirls over the ocean, rains and winds create a powerful winding vortex of clouds that pick up speed and travels over waters and land, threatening to destroy everything in its path. And one of the most powerful hurricanes ever to make landfall in recorded human history was Hurricane Maria, which hit Puerto Rico in 2017.
I'll tell you, there's a before and after Hurricane Maria in Puerto Rico. You can see the drastic changes.
Before Maria, the forest of Puerto Rico were lush and dark. Iguanas and little crusted anol lizards hid in tangles of leafy tree branches. The song of bird and kis filled the moist air. But Maria came with winds over 150 mph. It's like a speeding train running into the forest and it brought waters that flooded the entire island. Rio
the rivers carried water to places you'd never think it could go. Entire rainforests were chopped down by the winds and rain. The floods carried away birds, lizards, frogs, cows, and horses. And even caves were flooded, carrying away bats.
There were places where not a single leaf remained standing. Like it was it was very strong.
After Maria passed, the humans of Puerto Rico began slowly rebuilding their lives. But the forest take decades to regrow. And even if human beings planted thousands of trees a day, it would take years to get back to the amount of trees that stood before the storm. But fruit eating bats like Stenoderma, they're responsible for up to 95% of the regrowth of tropical forests after destructive events like hurricanes. 95%. Yep. And so after Maria, they got straight to work with their
go poop. You heard that right. Poop. Kaka aka guano. A special name for a bat's special poop. The secret to how this tiny freaky fruit eating bat actually regrows a forest after a hurricane is through its poop. As we've learned on terrestrials, squirrels will sometimes help plant trees by forgetting where they buried their nuts. But there are no squirrels in the tropical forest of Puerto Rico. And birds, well, they can eat and poop out seeds that turn into new plants. But after Hurricane Maria, they had nowhere to escape the hot sun that beat down during the days as the island roasted without the shade of trees. So many of them left. What about a creature that digests seeds in a more plant friendly way than squirrels? That flies all over the place while pooping and is impervious to the hot sun because it comes out at night. Enter the cow stenoderma
bats. They're not only picking up the seed and dispersing it here. They're flying away with it and dispersing it in very distant places.
Scientists have seen that fruit bats travel to far off spots in forests that have been destroyed. And that unlike birds who mostly eat where they find food, bats often take their food to go, meaning they're spreading their poop around in more places. Some bats eat more or less 20% of their body weight when they feed each night.
That would be like me eating a week's worth of food in one meal. Imagine you eat 20% of your body weight. What are you going to do when you get home? You poop
a lot. It's raining poop. Hallelujah. It's raining poop. Oh, poop. And while Stenoderma might be a little too smart to get trapped in our nets, at the end of our night hike in Puerto Rico, we actually do come across what looks like their poop filled with seeds from a native plant.
Look at this. This is what they eat. Wilin shines his head lamp on a tree that has what looks like a tiny ear of corn on it. When most other animals poop out the seeds that they eat, they're often too digested to grow into plants. But when our flying puppy friends take a little bite, the seed in question enters the most magical chamber of forestry generation known to humankind. A bat's furry little digestive system. That's right. Because when a fruit bat poops out a seed, it's ready to be planted in the ground and turned into a plant through a process called scarification, where a bat's gut juice breaks down the shells of certain seeds just enough to get them ready to grow. Plus, bat poop is an amazing fertilizer for the soil.
All of this combined is why fruit bats are known as the best reforesters on the planet. So, for keeping our forest happy and healthy, we want to have bats around because they are the ones that are helping us planting this forest without us even actually having to try.
Tropical forests like the ones in Puerto Rico clean the Earth's air. They pull out huge amounts of carbon dioxide from the air, which makes it easier for us humans to breathe and slows down the warming effects of climate change.
Plus, tropical forests are home to millions of species. Insects, birds, reptiles, amphibians, and mammals that rely on the trees there for habitat. And after disasters like hurricanes and landslides, and even when human beings chop down trees for roads and buildings, it is the fruit bats who come in under the cover of darkness and lay the seeds of a new future. These creatures that so many people think are scary and ugly and bad and are actually saving our forest every single night. And the evidence is all around us.
I was walking through the forest as the sun went down. When up in the trees, I hear a screeching sound. Startled, my eyes search all around. And to my spooky surprise, this is what I found.
The bats. Creatures of the night. The bat. I see them take to the sky. The bats.
They go squeaky squeaky squeak. I really started to freak, but then I saw something that was pretty neato. a divebombing bat scarfing down a mosquito. This brown bat doesn't want to suck your blood. Instead, she said, "I want to eat your bug. Phw. I use echo. Echo echolocation. I hunt in the dark using sound vibration."
She introduced me to a bat that I'd never heard of. My smooshed nosed cousin named Stenoderma. A pointy eared fuzzball that's super cute with teensy crooked teeth. More chomping fruit.
The bats. Creatures of the night. I see them take to the sky. They go squeaky squeaky squeak.
There's really no need to freak. This fruit bat explained, "We're not all that spooky." And she told me about her super poopy. My gut does a thing called scarification. It helps with fruit seed germination. When she poops out the seeds from the fruit that she eats, I throw a forest full of fruity trees.
The bats. Creatures of the night. The bats. I see them take to the sky. The bats.
They go squeaky squeaky squeak. There's really no need to freak. The batty Alan Goinsky. And there is nothing else cool about to happen. What's that?
Excuse me. I have a question. Me two. Me three. Me four. The badgers. [groaning]
Listeners with badgering questions for the expert. You ready? Absolutely. Hi, my name is Judy. I'm 9 years old. Do any bats sleep right side up?
Not that we know of. Uh, bats evolve to sleep upside down. And if you look at them carefully, their knees bent back. Angel explained, "Not only do they all sleep upside down, they also take off for flight upside down, just kind of fall off the branch and start flying, likely because they are too heavy uh to easily take off from the ground."
And that is an adaptation that all bats have to be able to roost upside down and be able to take off.
Hi, my name is Sam. I'm from Brooklyn, New York, and I'm 4 years old. And my question is, can bats swim?
Some of them can. I mean, I don't think that they would be, you know, Michael Phelps type of swimming, but they can move in water a little bit.
Especially splash splash. I was just picturing forget the doggy paddle, I got the fatty paddle.
Getting soggy. Um, hi, my name is Sophie and I feel zone. My question is, why is there so many species of bats?
Right now, we are at 1,48 something. So bats generally are about 20% of all of the mammal diversity that we have in our planet.
20% of all mammals are bats. That's right. And they live in all sorts of continents except for like the really freezing ones. Of course,
it's a bat's world and I'm just living in it. Hi, my name is Charlie. I am 6 years old. And my question is, how big was the biggest bat ever known?
The largest bat has a wingspan of about 6 ft. Wow. That's like Dracula spreading his arms.
Yeah. And then like the body is like a little dog. Hi, my name is Stanley and I'm 5 years old. Do different bats make different sounds?
Yeah, different bats will echolocate at different levels. Leafnose bats typically are known as whispering bats because they're flying among the trees and they don't need a really loud echolocation call. But bats that exist in very open spaces, they need to echolocate really loudly. They just kind of want to be able to detect this insects that they're eating even from a long distance.
And those creepy folded noses that some bats have, they're actually helping them hear like an antenna. An antennosse.
And they use that nose to kind of almost direct where these calls are going. The nose is actually quite movable. You can see them kind of like almost like digging like bewitched. Oh, like the little nose scrunch from Bewitched.
Do you move her nose like that? Anna, I've got one more question. Uhhuh. What do you think a blood burp smells like?
Oh, like a penny. All right, that's where I got to leave it. And I'm not going to tell you that there is this one species of bat whose tongue is way longer than the length of its body, which would be like as if the average human had an 8ft tongue just like walking around. Uh, I'm not going to tell you that cuz I'm nice, but I would name that bat the Rapunzel tongue bat. But it's not named that. is actually named the tube lipped nectarbat aka Anura fistula. Uh anyway, that's it. Terrestrials was created by me, Lulu Miller with WNYC Studios.
It's raining poop. Hallelu. This episode was reported and produced by Anna Gonzalez. Uh did I mention I am the president of her fang club? Her Fang Fang Club with beautiful sound design by Mera Batwintonic. actually Burman Tonic. Our executive producer is Sarah Samback. Our team also includes Ellen Gaffinsky, Tanya Chala, and Joe. Factecking by Emily Kger. Anna, any special thanks this episode? Special thanks to the American Museum of Natural History and Angeloto and Conserv Puerto Rico. Gracias. Uh, support for terrestrials is provided by the Simons Foundation, the Arthur Vining Davis Foundations, and the John Tumbleton Foundation. Fang you.
Also, big fangs to Zach Gdder Cohen. Uh, and I think that's it. I was kind of winging the credits, but uh, I squeaked them in. That's it. See you in a couple spins. This dirty old planet of ours. Bye.
Questions about this episode
What is "The Night Flyer: How Bats sPOOkily Revive Forests | Terrestrials Podcast" about?
The content explores the vital role that bats play in ecosystems, focusing on their ability to rejuvenate forests and maintain biodiversity through their unique behaviors. Featuring insights from a bat researcher, the narrative highlights the intriguing characteristics of these nocturnal creatures and their often-overlooked significance in environmental health.
What is mentioned in this Radiolab episode?
81 people, works and ideas are mentioned, including Stenoderma, Terrestrials, Batman, Count Dracula, echolocation, Alexis Wilkins. Each one on this page links to its own page with every episode that mentions it.
How long is "The Night Flyer: How Bats sPOOkily Revive Forests | Terrestrials Podcast"?
The episode runs 26 min; the transcript is about 4,203 words in 98 timestamped sections.
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About this transcript: the episode's spoken words as captioned on YouTube, split into timestamped sections. Reclip.Me locates every person, work and idea in the text, keeps the time it is first named, and quotes the words around it verbatim. Last updated December 15, 2025.