Since the white-nose syndrome was first discovered in the early 2000s, it has spread to caves across the continent. Now the fungal infection threatens the extinction of several bat species. But high-tech solutions are in the works.
Audio equipment helps researchers monitor bat populations by listening to them. Artificial light is used to draw insects around caves, making a simple meal for bats weakened by disease.
White-nose syndrome is devastating. But it conducts research that can promote human understanding of bats and of wildlife diseases as a whole.
Host: Morgan Springer Producer: Patrick Shea Editor: Morgan Springer Additional Editing: Dan WanschuraMusic: Gillicuddy and One Man Book
MORGAN SPRINGER, HOST: In the early 2000s, bat biologists in New York State went deep into a cave where they found an unpleasant surprise.
TINA CHENG: Instead of seeing, you know, tens of thousands of these bats crashing over the roof, they spotted piles of dead bats on the floor.
SPRINGER: It’s Tina Cheng, a computer scientist at Bat Conservation International. She says these biologists had stumbled upon the first known case of a disease now called “white-nose syndrome.”
CHENG: It is a fungus that grows on the skin of bats. So it actually digs into their epidermal tissue. And so when they are very infected, they actually have these little white, cloudy spots with fungal growths on their noses. Hence the name white-nose syndrome.
SPRINGER: The early case in New York killed almost an entire colony of an endangered bat species. Today, the fungus has spread to caves throughout North America. And Tina says that when a cave gets infected, it means disaster for the bats inside.
CHENG: The mortality rate can be greater than 90 percent on average in one place. And so when you have a colony that can reach tens of thousands, it’s just a unique carnage.
SPRINGER: This is Points North: a show about the land, the water and the inhabitants of the Upper Great Lakes. I’m Morgan Springer.
Right now, the U.S. is deciding Fish and Wildlife Service to put another bat on the list of endangered species: the northern long-eared bat. Here in the Upper Great Lakes, it used to be plentiful. But the population has collapsed in recent years due to white-nose syndrome.
PATRICK SHEA, BY-LINE: To try to prevent extinction – and extinction of other bat species – researchers must first learn more about the problem and test some solutions.
RUNNING: It’s Patrick Shea. Hi Patrick.
SPRINGER: Today we will check out technology used to track the spread of this disease – and see if it gives bats a boost.
SHEA: To get a first-hand look, I took a trip about as far north as you can go in Michigan: the Keweenaw Peninsula.
BREANNA GUSICK: So just be careful, the steps get a little slippery where the water is.
SHEA: I walk down a steep, damp staircase into total darkness – and I follow Breanna Gusick, a biologist at Bat Conservation International.
SHEA: We’re about half a mile deep in the Delaware mine: one of many abandoned mine shafts in the region. One hundred years ago, people came here in search of copper. But we’re looking for something else.
BREANNA GUSICK: There’s a bat right over your head.
SHEA: It’s the end of May, and most of the bats sleeping here have already left the mine. But there are still a few here and there, hanging from the ceiling, bundled together in their own wings.
Some of them move and jerk – Breanna says that means they will soon wake up.
GUSICK: He’s not even shaking, so he’s not trying to wake up. He is asleep.
SHEA: Wow, he’s so motionless. He she.
GUSICK: Yeah, they do not move, it’s crazy.
This little brown bat is still like a statue – it does not even seem like a living creature. For…
GUSICK: Looks like he’s starting to go to the bathroom. If this had a white nose, we would see it in front as around the mouth area.
SHEA: The way white-nose syndrome kills a bat is by interrupting this stoic sleep. Because when fungus grows all over the face and up into the nostrils, you can imagine that it is a little uncomfortable.
When a bat wakes up from hibernation, it must raise its body temperature again. That burns energy it needs later in the spring. Infected bats usually die of exhaustion and starvation – either right there in the cave, or shortly after leaving it.
And as bat populations began to decline here, people noticed the difference.
COOL SEPPANE: I remember as a child seeing bats, because we used to have one of these floodlights out.
SHEA: It’s Kyle Seppanen. He is the wildlife coordinator for the Keweenaw Bay Indian Community.
SEPPANEN: And we’ll see bats swarming. And you think, “Oh, the mistakes are not that bad.” But it feels like the last couple of summers, especially that you go out there and you just turn them left and right.
SHEA: Kyle says white-nose syndrome is to blame for this – the disease started killing bats here in 2014. And there is evidence that fewer bats mean more insects. A small brown bat alone can easily eat up to 1000 mosquitoes in just one hour.
I ride with Kyle while he watches bats on the reserve, something he’s been doing for the last six years. And he’s not alone in noticing the more buggy summers since then.
AUSTIN AYRES: Last year was the first time I put a mosquito net on my head because I was so overwhelmed by it.
SHEA: Austin Ayres is a wildlife technician with the tribe.
AYRES: It almost felt like it was raining, just the amount of mosquitoes falling on me – landing on my hands, shoulders, my face. It was pretty overwhelming, and it’s the first time I ever thought “wow, we have a problem with errors right now, right?”
SHEA: Austin and Kyle both agree that insects can be a major nuisance. But they say the problem is much bigger than their own discomfort.
AYRES: You know, one of our relatives is suffering. And like Anishinaabe, one of our teachings is that we are the guardians of this land and the animals that live in it …
SHEA: Bats, specifically, are at the center of a traditional story related to the work Kyle and Austin are doing now.
It starts with the sun being caught in a tree, and stops the sunrise. Then a squirrel chews on the branches of the tree and releases the sun. But it has a price.
AYRES: It was so burned that it could see no more. And after it burned up and could not see any more, the Creator gave them echolocation and said ‘you will fly as well as the other birds. You stay out at night because the sun will be too strong for you. ‘
SHEA: The squirrel had turned into a bat.
SHEA: The really interesting thing about it for me is that the concept of echolocation is in that story.
AYRES: Yes. We call it traditional ecological knowledge. The reality is that our people are so old and we have lived so long that we have seen development happen. And so when we tell stories, especially traditional stories, it’s related to that.
SHEA: Bats are very difficult to count. They are only out at night, many species live deep in caves in winter; they are quite mysterious creatures. Earlier, researchers went into hibernation caves to try to get a rough count of the bats on the roof. But how can you be sure you are not counting the same bat twice? It is difficult.
So Kyle uses audio to track bat populations – audio recordings of bat calls. It does not give him an exact number of bats. But it indicates when there is an increase or decrease in bat activity. It also shows him where the most popular bat haunts are. We walk to the edge of a wetland, with a small stream meandering through.
SEPPANE: So this place is actually part of the Kelsey Creek system. It’s like a natural flight all the way from Lake Superior, all the way inland.
SHEA: Which corridor do bats use?
SEPPANEN: All right, yes. So this place has been heavily affected by the use of beavers, so there are many dams, many open pockets of water that bats can come and have a drink from. There are insects everywhere here. So I have a detector next to the dead tree that stands there.
SHEA: The detector looks pretty simple: just a long rod with a microphone on top. But what it does is very high-tech, and it’s the best way to track the spread of white-nose syndrome.
SHEA: As Anishinaabe has known for thousands of years, bats move around using echolocation. They make sounds that bounce off objects and back to their ears. It tells them where not to fly and where the insects are. But there are sounds that our ears cannot pick up. These acoustic monitors detect echolocation calls and represent them visually.
Back in his office, Kyle shows me how the shape of the sound tells him what kind of bat makes it.
SEPPANEN: So big brown bats, you can see that they have the big steep hill on it. And at the very end of it, they always come down. The path always falls.
SHEA: Kyle plays an amplified version from his computer.
SHEA: The weird, throbbing laser beam sound: that’s the call for the big brown bat.
SEPPANEN: Here is a slowed down version of it.
SHEA: The tribe’s acoustic monitors show a decline in these shouts, as well as shouts from small brown, tri-colored and northern long-eared bats. These species are all very prone to white-nose syndrome.
Kyle uploads these bat skulls to an international database so biologists can see the big picture. They may search for white-nose syndrome in areas that appear to be declining. And the odds are they’ll find it.
But this acoustic monitoring is really valuable at the local level as well, because it shows where the most popular places for bats are around the reserve. It will hopefully help in the future. If some kind of cure is discovered, Kyle will know the best places to find and treat bats.
Bat Conservation International is trying out one treatment. Back at the Delaware mine, Breanna Gusick takes me to her campus.
GUSICK: I’m actually going to go and check all my gear. But we can not actually go up to it from here, we have to go up the hill and walk to get to it.
SHEA: We’re starting to climb out of the mine shaft. The project we are going to see is part of a nationwide experiment. Tina Cheng, who you heard from the intro to this episode, helped start what she calls the “fat bat program”.
CHENG: This came from something we call the fat bat hypothesis. So there was a researcher in Pennsylvania who noticed that some of the bats that actually survived and persisted through the disease wave, he noticed that they were really fat. As much fatter than he had noticed before the disease wave.
SHEA: So Tina and her colleagues wondered if that might be the key. Get your bats fat enough to survive the winter, even if they are infected with the fungus.
We come out of the dark cave into the wind and sun. I follow Breanna to another entrance to the mine. There are solar panels and high-tech research equipment, set up in the middle of antique mining equipment. You can still see the wooden platform where trains used to load copper. So there is this strange mix of historical artifacts and futuristic gadgets.
GUSICK: I’ll check the light first since it’s almost nine o’clock. I want to make sure it’s set up.
SHEA: An ultraviolet light bulb is programmed to attract swarms of insects every night. Breanna calls it a “bug buffet.” When bats appear weakened from white-nose syndrome, it is hoped that this cache of insects will build up its strength.
The light flashes on as planned. It is a small, halo-shaped bulb. Last winter, biologists put tiny microchips in the backs of about 300 bats here. As the bats fly through a hoop-shaped scanner near the bulb, it detects these microchips and identifies individual bats.
GUSICK: If the bats keep coming back to the same places to sleep and they are tagged, we will see when they come back and leave, and hopefully they can also see their survival.
SHEA: Breanna shares the data from the scanner with her colleagues. People like Tina Cheng, who sifts through data from error buffets in seven different states.
CHENG: And so we’re really trying to expand geographically to first test the concept “if you build it, will they come?” If you build it, will the errors come? Are the bats coming? And will the bats actually use these insect buffets to search?
SHEA: I asked if the insect buffets seem to increase bat survival. But they have only tried this for three seasons, and Tina, as a good computer scientist, says that it is too early to say. Besides, she does not want to give too much away.
CHENG: We are actually working on publishing our first results. But spoiler warning that we’re found out that bats are actually coming. We have evidence that bats actually use these insect buffets.
SHEA: White-nose syndrome is by no means a good thing, but Tina says it’s a bright side. Researchers gain a lot of critical knowledge when they respond to this disease.
CHENG: Oh, one hundred percent. This has done a lot of research to help us understand the natural history of bats, bat immunology, and I would say that even beyond bats, wildlife disease is a discipline that gets a lot of attention, not only because it is often linked to human health but because it actually adds a lot. pressure on global biodiversity.
SHEA: There is other research that looks at vaccines and disinfection to treat the fungus directly. But in the meantime, Tina hopes that these insect buffets will lead to fatter bats and less carnage in caves.
