Biologists and cavers, including high school kids, are venturing beneath the earth’s surface in a wide-ranging research effort that is dramatically expanding our understanding of an ecologically essential creature: bats

Story By Myers Reece | Photography by Lido Vizzutti
When we arrived at the cave’s mouth, nestled within Glacier National Park’s limestone wilderness, Hans Bodenhamer announced that we would only have to belly crawl “a little ways” to enter the underground labyrinth. He was giddy about our prospects of finding bat poop.

Bodenhamer is a light-hearted man with a jokester streak, but he was very serious now. I exchanged glances with the photographer, and we both seemed to be recalculating our expectations of the day. Bodenhamer had already underestimated the length of the hike in, so I decided to eat another Clif Bar.

In addition to the three of us, our small crew included Gabby Eaton, Bodenhamer’s star pupil from the Bigfork High School Cave Club, and Lisa Bate, a Glacier Park wildlife biologist. The goal was for Bate to install ultrasonic echolocation detectors in two caves to track the movements of bats, a creature that hadn’t been inventoried at all in Glacier until she began her groundbreaking research four years ago under the tutelage of renowned bat expert Cori Lausen.

Before entering, we stood on a ledge of the limestone rockface and changed from hiking clothes into attire more suitable for the damp, 37-degree underground climate, which was 45 degrees colder than above surface. For Bodenhamer, this meant a full-body, waterproof “cave suit.” Eaton and Bate also wore sensible, water-repellant outfits. The scraggly journalists made do with jeans. We all wore rubber or leather gloves and helmets with headlamps affixed to the front.

The entrance was initially tall enough for us to stand, but it quickly narrowed to a 10-inch gap that forced us to drop to our bellies and slither through, the top rock rubbing on our backs and the bottom jutting up against our stomachs. Plunging into pure blackness, it wasn’t a journey for the claustrophobic.

After wriggling through the constricted flue, the passageway opened up into a dank tunnel that allowed hands-and-knees crawling and occasional crouching, even hunched-over walking. Then, with Bodenhamer and Eaton leading, the tight duct suddenly gave way to a spacious cavity, or “room,” where glistening flowstone walls crested at a 20-foot-high ceiling splashed with reds and browns. Everybody could mill around fully upright.

Bodenhamer looked perfectly at home. Indeed, it’s as if we’d been working all day just to get to his living room.

“I love it down here,” Bodenhamer said. “It’s like a giant underground gymnasium or an underground obstacle course. You’re crawling around and it’s dark. It’s just so foreign to our own experience.”

Caves form naturally through weathering and erosion, and they’re found across the globe in a variety of climates and terrains. Glacier Park is dotted with them, while the Bob Marshall Wilderness resembles “Swiss cheese,” Bodenhamer said, with dozens all over its landscape. Montana’s longest is the 20-mile Bighorn Cavern, a far cry from the world’s most extensive system, Mammoth Cave in Kentucky, which has 400 miles thus far surveyed.

But Big Sky spelunkers – who typically prefer the title “cavers” – enjoy the mystery of Montana’s subterranean secrets, which exist far out of the public eye and consciousness. And every once in awhile, they stumble upon a treasure like the Tears of the Turtle Cave in the Bob Marshall Wilderness, the deepest limestone cave in the continental U.S. at 1,629 feet, discovered last year by the Northern Rocky Mountain Grotto.

Wildlife biologist Lisa Bate gets ready to enter a cave in Glacier National Park

Wildlife biologist Lisa Bate gets ready to enter a cave in Glacier National Park

It takes a specific breed of person to see a tiny opening in a rock wall and instinctively try to squeeze through it. Bodenhamer, when he was thinner and more limber, snaked his way through slits as skinny as 6 ¾ inches. Sometimes, thousands of feet of pristine cave awaited him. Other times, he had to immediately go back out the way he came in. So long as he could fit his head, he could maneuver the rest of his body through. To demonstrate this point, as a teenager he once wormed his way into a gap in the school bleachers. Unfortunately, someone sat down, and he walked away with bruised temples and a headache.

Bodenhamer, a 57-year-old earth science teacher at Bigfork High School, claims membership to a relatively small tribe of hardcore cavers in Montana, and beyond, who are drawn to worlds beneath the earth’s surface just as divers are to the deep sea and astronauts are to space. They’re all explorers, driven by the same relentless curiosity and thirst for adventure, but they’ve each chosen a different medium.

Bodenhamer’s obsession started as a boy when he visited Devil’s Den in Gettysburg, Pennsylvania. He continued his subterranean voyages through high school and as a young man, when his athleticism was at its peak and his prudence hadn’t yet matured.

“We’d do harebrained stuff, like rappelling off 500-foot cliffs and swinging into cave entrances,” he said, adding that one incident left him “cotton-mouth terrified.”

In 1984, he and a friend covertly floated the Colorado River without a permit, in search of little-known caverns along the Grand Canyon. They were promptly arrested. But a few weeks later, the National Park Service called and offered him a job in cave management. He was able to utilize his civil engineering education in exploration and conservation, which would evolve into a lifelong passion project.

To date, he’s ventured into 1,500 caves nationwide, about one-fourth of which were discoveries or first explorations. He’s mapped 120 in Montana, including quite a few in the Bob Marshall Wilderness.

In the 1990s, Bodenhamer accepted a teaching job at Browning High School and moved his family from Arizona. At Browning, he started taking his geology students on field trips to caves, which led to the formation of a spelunking club. After he transferred to Bigfork High School, students there lobbied for their own group.

Since its formation in 2005, the Bigfork High School Cave Club has in many ways separated itself from standard extracurricular groups. Students not only learn scientific research and geographic information system (GIS) principles, but they are given the chance to apply that knowledge to meaningful work with real-world implications, which has led to a series of grants from multiple state and federal agencies.

The club’s central function is “resource monitoring,” in which it logs observations, photos and data regarding formations and conditions, mineral deposits, climate, organisms and more. The students use GIS to organize and analyze the data. In Glacier Park, they’ve worked in 15 caves, creating detailed maps for four and conducting microinvertebrate population studies for four others. Their findings are considerably more extensive than those of Newell Campbell, who first mapped Glacier caves in the late 1970s.

The adult equivalent to the club, albeit on a larger scale, is the Northern Rocky Mountain Grotto, Montana’s only recognized chapter of the National Speleological Society. The grotto has over 100 members and proclaims that caving is “in our blood – why else would we descend below one of the most beautiful places in North America.”

Bate, Bodenhamer, and Eaton, left to right, stop to inspect the walls of a cave in Glacier National Park

Bate, Bodenhamer, and Eaton, left to right, stop to inspect the walls of a cave in Glacier National Park

Altogether, the Bigfork club, which usually has around 10 to 15 members each year, has visited roughly 50 caves, including 20 in five different national forests statewide, as well as four beneath Bureau of Land Management land. The BLM work has important conservation implications, with two of the caves containing fragile mineral deposits and the other two providing habitat for bats.

In 2009, the club received the EPA’s President’s Environmental Youth Award. In addition to the monitoring and GIS work, the award recognized the students for removing graffiti and trash from caves. They were also invited to the International GIS Conference in San Diego, where they spoke to a crowd of 10,000.

Though the group hasn’t outright discovered any caves like Bodenhamer has on his own, students have entered caverns where probably no more than 10 humans had ever previously set foot. In 2011 and 2012, they received funding to study 16 caves in the Grand Canyon, including the same ones Bodenhamer had visited almost 30 years earlier.

Beyond maps and data, Bodenhamer believes the club’s greatest contribution is life experience: getting kids outdoors and interested in exploring worlds outside of their comfort zone, and certainly far outside of their computer and phone screens. As the years go by, they might not remember much about their earth science class, but they’ll never forget rappelling in the Grand Canyon or snowshoeing in the dead of Montana winter.

Eaton, who is entering her junior year at Bigfork, is evidence of Bodenhamer’s contagious enthusiasm for spelunking. The 16-year-old transforms from a soft-spoken, slightly timid teenager into an intrepid explorer the moment she steps off the field trip bus, or in the case of our recent summer-break excursion, Bodenhamer’s van. Bodenhamer hopes one day his club will be able to obtain its own van, which he says would be more economical than buses.

“I love being outside and I love being part of helping something,” Eaton said, referring to the club’s conservation values. “The bats are the best.”

Eaton, participating in her third year, already has 20 caves under her belt, including ones that required pinpoint rappelling and wading in chest-high water. Some students have graduated with 400 volunteer hours on their resume, all from the club. Bodenhamer says state and federal agencies don’t always have funding for this kind of research, and his kids are happy to help.

For Bate, the high school students have been vital. She had never been to any of the park’s caves when she began heading up its  first-ever bat inventory research project in 2011. But the cave kids had, and they showed her the way.

Even on the late-August trip, when she was visiting locations she already knew, Bate felt more comfortable having the club’s guidance. That day, none of the other members could make it, but Eaton and Bodenhamer proved to be invaluable resources once again. Owing to their subsurface agility, the pair volunteered to place the detectors, employing MacGyver skills to secure the devices with thin rope on craggy overhangs.

“They’ve been great,” Bate said of the club. “It’s really amazing what they do.”

Bate’s specialty is birds, but she has become a crash-course authority on bats. Her work is both urgent and unprecedented. Since 2006, a fungal disease called white nose syndrome has killed millions of bats in 25 states and five Canadian provinces. In the northeastern U.S., up to 80 percent of bats have died. The closest it has come to Montana is Minnesota and Oklahoma.

“Before we started, we really didn’t know anything about bats in the park,” she said. “So it’s been an honor to be a part of this research.”

Bate, Bodenhamer, and Eaton, left to right, stop to inspect the walls of a cave in Glacier National Park

Bate, Bodenhamer, and Eaton, left to right, stop to inspect the walls of a cave in Glacier National Park

Since most people don’t give bats any thought, or dismiss them as gross if they do, news of their demise doesn’t always resonate. But biologists say it’s wrong to think of them as pests, because in reality they’re a highly effective means of pest control, consuming incredible amounts of insects – a single little brown bat can eat 1,200 mosquito-sized bugs in an hour. Large decreases in their numbers would logically lead to substantial increases in bugs, potentially causing significant environmental imbalances.

The U.S. Geological Survey’s National Wildlife Health Center says that the “true ecological consequences of large-scale population reductions currently underway among hibernating bats are not yet known.” But the agency goes on to cite a study that estimates the value of bats’ insect-suppression impact on U.S. agriculture at between $4 billion and $50 billion per year.

Bate’s work is part of an extensive study that has brought together a long list of state, federal and tribal agencies. Her findings are compiled with mountains of data from other researchers across Montana and into northern Idaho, North Dakota and South Dakota. Biologists and wildlife managers hope to gain a better idea of how to combat white nose syndrome if it comes to Montana, or maybe prevent it from ever taking hold.

Much of the focus is on identifying and protecting roosting areas, especially hibernacula, because the disease predominantly affects hibernating bats. Researchers have planted 65 detectors in caves and at other potential roosting sites such as bridges, mines and trees. They’re also studying climate and habitat variables, as well as other threats like wind turbines. They catch bats in nets for more thorough observation.

Bryce Maxell, senior zoologist with the Montana Natural Heritage Program, the study’s lead organization, says some regional baseline bat data existed before 2011, but concern over white nose syndrome and technological advancements in monitoring equipment have catalyzed a vast expansion in our understanding of these essential winged mammals. Among the most encouraging discoveries is Montana’s lack of large, densely populated hibernation roosts, which tend to promote rapid spreading of disease.

Bate’s findings have documented three previously unknown bat species, giving the park a total of nine distinct species. Statewide, 14 or 15 have been identified. This knowledge could prove crucial because white nose syndrome impacts different species in varying ways.

“There’s a pile of golden data that we’re mining and mining and mining,” Maxell said.
Maxell and Bodenhamer both praised the project’s across-the-board collaboration, with agencies relying heavily on caving groups like the Bigfork high school club and Northern Rocky Mountain Grotto, seeking out their institutional knowledge, maps and data, and continually updated observations. Bodenhamer says many states see conflicts between cavers and management agencies.

“Here we’re getting along; Montana is really collaborative,” he said. “I can say we’re a model.”

Bigfork High School junior Gabby Eaton stands near a waterfall inside a cave in Glacier National Park

Bigfork High School junior Gabby Eaton stands near a waterfall inside a cave in Glacier National Park

Beyond serving as homes or hangouts for various organisms, and as underground gymnasiums for adventurers, caves are important repositories of history. Their walls and formations provide clues into a region’s physiographical evolution and ancestral inhabitants. Even their less desirable features tell a story, like the dense layers of rat poop that made up the floor of one of the caves we visited. Carbon-14 dating found droppings that were 3,000 years old.

But like their winged occupants, caves are often misunderstood, and undoubtedly misused. There’s something about them that stirs up the inner vandal in people, resulting too frequently in trash, graffiti and broken stalagmites and stalactites, which may be thousands or even millions of years old. For something made of stone, caves can be fragile.

“They’re nonrenewable resources,” Bodenhamer said.

In Glacier, a special backcountry permit is offered for only one of its caves, and park officials are reluctant to even promote that one. Bodenhamer estimates that 50 to maybe 200 people per year visit the open cave. The locations of the park’s other ones are not made publicly available, and in order to receive permission to accompany Bate, I had to agree not to disclose any geographical information.

Bate collected samples of bat guano inside both caves. Between the ultrasonic loggers and DNA from the droppings, Bate can glean an idea of what species use what caves at certain times of year.

Beyond occasionally pointing out some guano, which often turned out to just be discoloration, the photographer and I were likely hindrances. But our hosts patiently waited when we needed rest and showed us the secrets to spider-manning across crevasses by using walls on each side.

Nearly 1,000 feet from the cave’s entrance, we reached our destination: a waterfall. Although the cave went back thousands of more feet – a mile altogether – our goal was only to see the cascading water and turn around.

There’s a strange beauty to a waterfall tucked away in earth’s hidden depths. It seems out of place, a reminder of just how far out of place you are, although you wouldn’t have known it from looking at Bodenhamer or Eaton.

Standing in a chamber of endless night, Eaton gazed up at the waterfall as our headlamp beams illuminated water droplets misting onto her helmet and face. When the light hit just right, we could see her eyes, calm but focused, growing ever brighter in the darkness.