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Frog-Spotting in One of South America’s Least Accessible Mountain Ranges

A team of herpetologists trekked into Peru’s remote Vilcabamba Range and discovered animals found nowhere else on Earth.

A new species of frog in the genus <em>Pristimantis</em> discovered near Camp 3.
A new species of frog in the genus Pristimantis discovered near Camp 3. Giussepe Gagliardi

“The way we’re exploring this is not much different from how Humboldt or Wallace or Darwin got to these places 200 years ago,” José Padial explained one morning last February, as gauzy light slanted into a forest clearing deep in Peru’s remote Vilcabamba Range. His team had just slashed through a mile of steep jungle with machetes, collecting dozens of specimens—from iridescent lizards to unremarkable brown frogs—many of which appeared to be new to science. Padial had almost trampled on a bushmaster, one of the hemisphere’s most dangerous snakes, and now heard rumors that some members of the local Asháninka community were plotting to block him from leaving their territory with specimens he had government permission to collect. Camped just below 2,000 meters (6,500 feet) in a damp patch of cloud forest, the herpetologist was two weeks into his expedition but still several days from his goal—the isolated grasslands atop one of South America’s least explored mountain ranges. His most reliable source of navigating the team’s route there were some low-resolution images he’d printed from Google Earth.

Not that any trail map—or trail—existed. Few humans had ever set foot on the upper reaches of the Vilcabamba Range, a northeastern spur of the Andes that juts like an archipelago into the sea of Amazon jungle. And fewer still in the half-century since two wealthy New Yorkers, Brooks Baekeland and Peter Gimbel, became the first to do so, dropping by parachute onto a 10,500-foot-high grassy plateau in 1963. Lured by stories of Incan gold, ruins, “Indian taboos” and “sacrificial lakes in the sky,” the explorers instead encountered a primeval landscape of soggy Sphagnum bog, hilly prairie, and stands of pygmy bamboo. With two companions, they spent more than two months bushwhacking down to the Amazon basin, surviving blinding wasp stings and spooked natives with bows drawn. National Geographic’s title of the account suggested a fairytale: “By Parachute into Peru’s Lost World.” Baekeland, the grandson of the inventor of Bakelite plastic, would later recall the pioneering trek “as though in a nightmare.”

“Part of me wonders if we should have parachuted into the upper part of Vilcabamba,” Padial wrote on the expedition’s Tumblr blog before leaving Pittsburgh, where the 39-year-old Spaniard serves as the Carnegie Museum of Natural History’s assistant curator of amphibians and reptiles. He knew that reaching the highlands by foot—during the height of the rainy season—would be a slog. He’d tried before, in 2008, but never made it above 1,800 meters (6,000 feet). Improvising a route through steep, tangled jungle and schlepping tents, tarps, cooking pots, camera gear, solar panels, and food for at least a dozen people between successive base camps required ample trailblazers and porters. Padial expected to have little trouble finding local Asháninka willing to work, and offered more than twice the going wage. Still, he struggled to recruit just six of them. The cold, lofty terrain, the time away from families—most able-bodied workers simply didn’t care for the job description. One porter bruised his knee after a week and went home. Another, a 14-year-old named “John Clever,” shot a kinkajou, a raccoon-like creature one night, and after gutting and smoking the animal until morning, descended with it and never returned.

The Pichari River, a tributary of the Apurimac, and the Asháninka community of Marontuari.
The Pichari River, a tributary of the Apurimac, and the Asháninka community of Marontuari. Andy Isaacson

Scientific exploration in the remotest parts of the world is impossible to script. Every one of Padial’s expeditions has involved some unanticipated mishap, some checked ambition. The previous year, while exploring a rugged swath of Amazonian jungle along Peru’s border with Brazil, his team showed up at an Asháninka community with 20 days’ worth of gear and provisions, and permits from local officials granting access through the territory. The community welcomed them, offered shelter for one night, and then, refused to let them pass. Complications like this come with the territory, however, and for Padial and the other biologists are the cost of achieving the ultimate goal: finding something no human has ever seen. “We all have this draw of early explorers,” he told me. “We want to go to those places where no one has been before, and be the first to find these animals.”

There is scientific importance to such a quest, of course. Each discovery brings new perspective about the planet’s biological diversity, and helps us understand how much we are losing every time we decide to bulldoze or clear-cut an area. “At the least, we leave a record behind of what there was there at a time,” Padial says. Simply knowing what lives where also helps to fill gaps in the tree of life, the genealogical relationships among species. Every undiscovered organism out there, Padial explains, is a missing link in our understanding of evolution as a whole, as species are the entities that actually evolve.

“If you don’t discover these species and give them a name, they pass unnoticed. They don’t exist.”

The Vilcabamba is filled with unnamed species, Padial believes. Biologists have long suspected that its range of elevations and wide variety of habitat types harbor a tremendous diversity of animals and plants. The few scientific expeditions ever to have penetrated its vast, untrammeled wilderness encountered several new species in “unexpected habitats or in surprising abundance,” according to one account. Logging, natural gas and oil exploration, and agriculture now threaten to fracture this pristine picture, and Padial hopes that by shedding light on the region’s richness, this expedition—officially titled the Carnegie Discoverers Expedition to Vilcabamba—might begin to make the case for its protection.


The team members play cards by the light of their headlamps.
The team members play cards by the light of their headlamps. Andy Isaacson

In camp, Padial poured himself a cup of rainwater-brewed coffee, and then gathered his team around an improvised table made of sticks to devise a way forward. Smoke billowed from the cooking fire, nestled against the base of a tree trunk, over which moss-covered logs had been stacked to dry. Padial laid out his Google Earth printouts and a topographic map. The satellite images showed a birds-eye view of the densely forested ridgeline they’d been tracing, the same ridgeline that continued to rise sharply above them to 2,500 meters (8,000 feet), zigzagging for a couple miles, and then sloping gradually toward a hilly prairie at around 3,200 meters (10,500 feet).

It was impossible to tell how long it might take to get there, but they had ten days to try. The team—six biologists (Spanish and Peruvian), a cook (also a Peruvian biologist), and Padial’s girlfriend, a Mexican dancer and filmmaker—was used to the uncertainties and deprivations of expedition life, anyway. Most had joined Padial on previous amphibian and reptile surveys. They hadn’t showered for days, and wore damp underwear and socks. By past standards of luxury, the French-press coffee maker that Padial had secured this time represented something five-star. More importantly, they’d heard the Vilcabamba highlands concealed a herpetological Lost City of the Incas, an irresistible quarry: frogs, toads, lizards, and snakes found nowhere else on Earth.

Padial had been looking for lost places ten years earlier, when he first spotted the 110-mile long mountain range while flying around South America on Google Earth. A rocky massif fringed with green, the Vilcabamba called to mind the tabletop mountains, called tepuis—the inspiration for Arthur Conan Doyle’s The Lost World—that loom above the Venezuelan jungle like islands in the sky and host species found nowhere else on Earth. “It looked high and isolated,” Padial recalls. “I thought, ‘Wow, it would be amazing to go there.’”

The Vilcabamba Range emerges out of the steamy Amazonian lowlands, at an elevation of around 450 meters (1,500 feet), and climbs to a jagged, central crest above 4,200 meters (14,000 feet). The local native groups—the Asháninka, Matsiguenga, Nomatsiguenga, and Yine—never settled the lofty interior, finding it too cold, wet, and lacking good soil and game. It remains largely virgin, free of roads, and enjoying token protection within the boundaries of Otishi National Park and two indigenous reserves. Cut off from the eastern slope of the Andes by the Apurimac and Ene rivers, a main source of the Amazon, and moated by deep valleys and gorges on all sides, its isolation has set the stage for a wide range of endemic flora and fauna to evolve. A frog living at 2,000 meters (6,500 feet) in the Vilcabamba cloud forest would have a long way to hop across several thousand vertical feet, through several foreign habitats, to reach familiar turf across the Apurimac. No chance. “The species that live in the upper area have probably been isolated from the rest of their relatives for a very long time,” Padial explained. Exactly how long these organisms have been isolated is one of the things he and the others aim to figure out.

The mountains are in a rich neighborhood already, ecologically speaking. The tropical Andes is considered one of the world’s 35 biodiversity “hotspots,” boasting the highest percentage of endemic plant and vertebrate species—creatures like the yellow-eared parrot (Ognorhynchus icterotis) and spectacled bear (Tremarctos ornatus). A recent survey of Manu National Park and its buffer zone, along the eastern slope of the Andes in southeastern Peru, counted 287 reptile and amphibian species (as well as more than 1,000 species of birds—around 10 percent of the world’s total) living there alone: the most diversity found in any protected area on the planet.

José Padial surveys the forest along the ridge above 2,700 m, between Camps 3 and 4.
José Padial surveys the forest along the ridge above 2,700 m, between Camps 3 and 4. Andy Isaacson

Lying 100 miles northwest of Manu as the parrot flies, the Vilcabamba Range, in contrast, remains terra incognita. Tough to access, no other area in the Andes of even remotely comparable size is still so poorly known to biologists. It has never been all that welcoming. Throughout the 1980s and ’90s, the Ene-Apurimac Valley was the heartland of the Shining Path, the Maoist guerrillas who terrorized Peru. Nowadays, the area is the world’s largest producer of coca, whose leaves are refined into paste at clandestine camps in the forest. Just south of Padial’s route, drug mules by the hundreds cross the Vilcabamba by foot, with medics and armed escorts. Encounters with traffickers can be tragic: Members of a Bolivian scientific team were slain in that country’s Noel Kempff Mercado National Park in 1986 after their aircraft inadvertently landed beside a clandestine coca-paste factory.

The few research efforts undertaken in the Vilcabamba Range over the years have managed to paint a picture of exceptional biodiversity. In the late 1960s, American ornithologists John Terborgh and John Weske mounted a series of landmark expeditions to study bird community structure along an altitudinal gradient from 600 to 3,520 meters (2,000 to 11,500 feet)—basically what Padial hoped to mimic for amphibians and reptiles. They recorded 405 species on the mountains’ western slopes alone. (It’s estimated that the Vilcabamba Range may contain more than half of all bird species known from Peru.) Then, in 1997, Conservation International and Smithsonian Institution surveys found many new species, including a pale grey tree rat the size of a domestic cat. Their report declared the area “a special place in relation to biodiversity.”

Padial’s first expedition there was sort of a misadventure. In 2008, he and his former Ph.D. advisor, Ignacio de la Riva, a biologist from Spain’s National Museum of Natural Sciences, led a team that attempted to reach the highlands by following a river upstream from Kimbiri, a tropical town along the Apurimac. Mapping a distance of five miles, Padial figured they could get there in two days of solid hiking. The terrain, however, proved far steeper, muddier and harder to penetrate than one could glean from a satellite image. After two weeks, exhausted and hungry, they turned back.

Padial knew better this time. He spent two years planning the expedition, securing funds from Carnegie Museum donors and permits from Peruvian government agencies. He’d negotiated delicately with the residents of Marontuari, the Asháninka community at the base of the ridge, gamely sipping their alcoholic homebrew of fermented yucca root from a hollowed gourd as they spoke about the threats to their territory from encroaching coca plantations and a planned hydroelectric dam, as well as their reservations about Padial himself. “They are very suspicious about what we do with the samples,” he says. “To them, it’s just weird, the whole idea of conservation—that someone goes and collects these animals that no one pays attention to. If you put money into something, [they figure] you’re going to get something.”

José Padial records the day’s observations in his field notebook.
José Padial records the day’s observations in his field notebook. Andy Isaacson

Rather than clamber upriver, his plan this time was to drive an hour into the Vilcabamba up a dirt road from Pichari, a sleepy town along the Apurimac, until it dead-ended in Marontuari. Bushwhacking from there to the highlands, his team would pitch successive base camps—where flat ground permitted—as the environment transitioned from lowland montane forest to cloud forest, elfin forest, and finally, the Puna grasslands, a treeless region found across the central Andes between 3,200 and 4,000 meters (10,500 and 13,000 feet).

When Baekeland’s team parachuted there in the 1960s, they glimpsed an Andean spectacled bear and a Peruvian puma, but little else. Three decades later, the biologists working with Conservation International—landing by helicopter—spotted guinea pigs, numerous grass mice, and a large arboreal rodent (family Abrocomidae) that resembled one known only from bones excavated from pre-Columbian burial sites at Machu Picchu, farther south. They collected just four species of reptiles and amphibians—three frogs and one lizard—but all appeared new to science.

For Padial, the promise of scientific discovery is what had lured him to herpetology. As an undergraduate in Spain, studying biology, he volunteered on a couple of field expeditions in the Bolivian jungle and kept finding it a struggle to identify the amphibians and reptiles he observed. Even today, no general field guide yet exists for reptiles and amphibians of the Amazon. While some 7,500 species of amphibians have been identified worldwide, untold thousands remain at large. Since 1985, the total number of recognized species has increased by more than 60 percent—a new species of amphibian is described in the scientific literature every 2.5 days. Yet knowledge of their diversity and distribution pales in comparison to what scientists understand about birds and mammals. “It’s just amazing how much there is to do,” Padial says.

In the past decade, he’s launched several successful, globe-spanning expeditions, including three trips to Mauritania that resulted in the first species accounts of amphibians and reptiles for that country, as well as a pioneering excursion into Peru’s Alto Purús National Park, a wild, poorly known patch of Amazonian rainforest home to several uncontacted nomadic tribes, that yielded several new species.

Putting animals on the map of science can serve a conservation goal, too. The Vilcabamba Range stands as one of the last intact tropical montane forests left in South America, a species-rich belt that once ran the length of the eastern Andes, from northern Venezuela south to Bolivia. Yet along its lower flanks, the elevation holding the most biodiversity, the forest is being destroyed at an alarming rate to make way for coca and coffee plantations. Illegal logging also chips away. Much of the interior is within the bounds of two indigenous reserves and Otishi National Park, but the park’s staff, which includes eight rangers charged with policing 1,100 square miles (an area the size of United States’ Yosemite National Park), have few resources to combat encroachment, not to mention drug traffickers traipsing around with weapons. Perhaps by shedding a light on the unique and extraordinary life in the Vilcabamba, scientific efforts like Padial’s could help Otishi acquire the resources needed for more robust protection, like those afforded to Manu National Park. And maybe somewhere high in “Peru’s Lost World” there lives a charismatic, endemic species of frog yet to be discovered that could become an emblem for conservation.

Throughout the expedition, the scientists often encountered animals by happenstance—a lizard found skittering between campfire logs, a frog startled during a walk to pee. But since many amphibians are nocturnal, the best chance of finding them is to go probing after dark. One evening at Camp 2, as with most nights, Padial and the others strapped on headlamps and set out to collect. He wore rubber boots, square-rimmed glasses, and a collared shirt with pens tucked into the breast pocket. The group fanned out along with trail, walking slowly. They scanned leaves and tree trunks and poked at the wet leaf litter with sticks. Soon, Padial’s light reflected off the eyes of a small brown frog perched haplessly atop a leaf. He snatched the animal up, and holding it under the beam of his headlamp by its legs, gave it a quick taxonomic spot check.

A juvenile of a direct-developer frog in the genus <em>Pristimantis<em/>.
A juvenile of a direct-developer frog in the genus Pristimantis. Andy Isaacson

Padial specializes in New World “direct developers” (Terrarana), a sprawling group of frog families ranging from Texas to northern Argentina. Instead of laying eggs in water that hatch into tadpoles, Terrarana frogs deposit their eggs in moist dirt, or moss, out of which emerge fully formed juveniles. Most of the frogs and toads in the Vilcabamba were of this type, as the steep slopes allow for few ponds or standing water.

Padial could tell immediately that the frog belonged to the genus Pristimantis, a large group of mostly terrestrial direct developers. But he was looking for traits that might help place the frog more precisely on the family tree. Did it have an exposed tympanum (ear drum)? Sticky toe pads? Was its belly transparent or pigmented, glandular or smooth? What kind of dot pattern colored the inner thigh for signaling the opposite sex? A few days earlier, Padial had collected a frog that at first glance resembled one he’d collected on a previous trip to the Amazon. But on closer inspection, he noticed its sharper snout and transparent peritoneum, the spider web like membrane covering the organs that on some frogs is pigmented. “Those are like the differences between a chimp and a human, like being fully covered by hair or not,” Padial explained. “I think it was a new species.”

He plopped the Pristimantis into a clear plastic bag along with some leaves to keep the frog moist. Searching for and catching animals was the fun part—Padial had been doing that since he was a kid, hunting snakes near his grandfather’s house on the outskirts of Granada, Spain. Later came the humdrum tasks: measuring frogs, counting scales, and analyzing anatomy, bone structure, mating calls, genes, distribution patterns and climate data. “You need music for that,” Padial confessed. The team’s forest lab amounted to a stick table covered by a rain poncho, surrounded by bags containing frogs, toads and lizards. Each specimen was first euthanized with a dose of Lidocaine, the numbing drug used by dentists, and tagged with a number. With tweezers, the researchers would then extract a tiny sample of thigh tissue for later genetic analysis, and finally inject formalin to fix the animal’s shape.

A tray of specimens collected during the expedition.
A tray of specimens collected during the expedition. Andy Isaacson

With data from his two Vilcabamba expeditions, combined with findings from the CI-Smithsonian surveys in the ’90s—the herpetological specimens collected then had yet to be fully analyzed—Padial hoped to assemble the best existing catalog of amphibians and reptiles in the Vilcabamba Range.

Although Padial and his team made important discoveries on the way up, in a sense this was all a means to an end. The ultimate goal was to survey the Vilcabamba’s upper reaches, a haven for endemic species. On the third week, an advance team that included Padial, a Asháninka father and son from Marontuari, and Angel Castellano, an Otishi park ranger, managed to hack a way through to 2,760 meters (9,055 feet). Their track wound past twisted branches carpeted with epiphytic mosses, and sprawling tree root systems that required vertical rock-climbing maneuvers. Passing over gaps in the vegetation where losing one’s footing could mean falling off a precipice, it made the well-maintained Pacific Crest Trail look like the Champs-Élysées by comparison.

Along the exposed ridge top, the cloud forest became a bushy elfin forest of tree ferns, bamboo, and reedy grasses. During breaks in the fog, creeping up from the valley, you could make out the jagged crest of the Vilcabamba Range, still some distance above. The change in scenery came with a host of new creatures; species like the cartoonishly bloated cane toad and electric blue poison-dart frog the team collected around Camp 1 were nowhere to be found. “It’s like going from Florida to Oregon—two different worlds,” Padial said of the transition. The biologists stumbled across what is likely an undocumented species of snake with vertical pupils and a black belly, and a tan-colored frog with orange eyes that is completely different from anything they’d found before. “We knew that if we could reach high altitude in this area we would find lots of new stuff,” he says.

<em>Ameerega macero</em>, a common Amazonian species of poison dart frog, found near Camp 1.
Ameerega macero, a common Amazonian species of poison dart frog, found near Camp 1. Juan C. Chaparro

Finding new frogs wasn’t like reaching a lost Incan city, admittedly. For the most part, the herpetologists reacted to each of their discoveries with the kind of enthusiasm a beachcomber might greet a curious shell or weird bit of flotsam.

But if there was any trophy Padial wanted from the Vilcabamba—a feather in his cap—it was a species of marsupial frog from the genus Gastrotheca, which carry their brood in dorsal pouches like eggs in a backpack. He knew that no Gastrotheca species from the area had yet been named, but he felt certain one must exist. “I would bet that the one here is probably cool,” he said. Camping in a humid dell a thousand feet below the grasslands, Padial and the others began hearing the unique tak-ta-tak call of a marsupial frog over the drizzle. The call would start and stop at random times, like a taunt.

One night after a meal of quinoa soup and dried meat, Padial went out looking with Giuseppe Gagliardi, a biologist at the Peruvian Amazon Research Institute. Gagliardi, who has lived all his life in Iquitos on the banks of the Amazon River, has a special knack for spotting frogs, and would have taken home first prize on the expedition had there been such a count.

At this higher, colder elevation, frogs and especially lizard populations were a fraction of what they were in the Amazon lowlands, but as the two walked through foliage dripping wet from fog and daily downpours, Padial sensed even lower frog activity than expected, probably due to the moonlight that filtered through the canopy. “We are always concerned about how many times the moon is going to be glowing when we plan the expedition,” he explained.

Gagliardi let out a forceful whistle, which sometimes stimulates frogs to vocalize. Not long after, they homed in on a Gastrotheca calling from high in a tree. Gagliardi took off his backpack and began to shimmy up the tree, breaking off decaying branches and bromeliads as he climbed. Suddenly, the calls stopped. Gagliardi paused and dangled there for a few minutes, but the frog never called again.

A month earlier, when Padial first arrived in Pichari at the start of the expedition, the director of Otishi National Park had introduced him to local military officials, who, in a gesture of goodwill and good public relations, offered to airlift the scientists by helicopter into the remote, central grasslands of the Vilcabamba Range. It was hard to refuse such a gift. But over the course of the expedition, nailing down that ride proved to be a relentless distraction. The general who’d extended the offer was reassigned, the military had other priorities, and the only means of receiving news from Pichari was a cell signal at 8,600 feet in the wilderness. Now, with possibly just two days of bushwhacking ahead of them before reaching the Puna—it was impossible to say for sure just how long it would be—word came that the helicopter was on.

Padial was torn. His team had spent three weeks gradually advancing up the mountain by then, erecting camps and hauling provisions. They’d already made a comprehensive inventory of the reptiles and amphibians living between 900 and 2,900 meters (3,000 and 9,500 feet), which had never been done before. With another thousand feet of thick forest to go, they were poised to break tree line, beyond which they’d face a much clearer path towards the Vilcabamba’s highest elevations. Flying there by helicopter would depend on both the fickle generosity of a local military commander and even more capricious weather. Padial had misgivings about packing everything up and hiking down. It was a gamble.

The team in Marontuari, awaiting a ride out of the wilderness.
The team in Marontuari, awaiting a ride out of the wilderness. Andy Isaacson

Still, time was running out, and the path ahead by foot was anything but certain. In a few days, he would lose three members of his team to prior commitments, and after Angel, the park ranger, sliced his leg with a machete, he was down to only two trailblazers. With hot showers and a rotisserie chicken meal beckoning below, Padial decided to wager on the airlift.

A few afternoons later, with clean clothes and high spirits, the team arrived at a walled-off military compound on the outskirts of Pichari. The airspace above the Apurímac valley was sunny and clear, although high in the Vilcabamba the skies appeared ominous.

“Buenissima,” Padial said, taking it all in. “I can’t believe it.” Then he corrected himself. “Well, I’ll believe it once we put our feet on that marshy grassland.” After posing for a group photo with the smiling regional general, the scientists boarded the Mil Mi-17 helicopter parked on the airfield.

The helicopter rose above Pichari, and banked around the Apurímac, ascending toward the Vilcabamba crest. The Asháninka, Efrain and his son Wilbur, snapped pictures with their cell phones as the helicopter flew over Marontuari and traced the Pichari River, following the ridgeline the team had spent weeks hiking. Beyond that, the virgin interior of the Vilcabamba unfurled below like a green shag rug, creased with steep-walled canyons and punctuated by waterfalls. As the helicopter climbed to nearly 4,000 meters (12,500 feet), it encountered a thick, chalky cloud ceiling that blanketed the upper mountains. The pilot maneuvered to find a visible path through into the highland plateau, where Padial had provided GPS coordinates for a couple of sites that, at least from satellite pictures, appeared suitable for setting up a camp. But the clouds were impenetrable. The helicopter flew in a wide circle to gain altitude: still more clouds. Stymied, the co-pilot signaled to Padial that they would have to abort the flight.

The next morning, and for the rest of that day, it poured in Pichari. With each dreary hour, Padial began to lose hope that the weather would allow another attempt in the helicopter. The military also let it be known that the ride offer had an expiration—24 hours. At daybreak the following morning, with clouds choking the upper slopes of the mountains—a familiar sight nearly every day of the four-week expedition—the team began packing for home.

Padial was crestfallen—they’d come so frustratingly close. He was annoyed at having put all his chips on the military’s shaky promise of a ride. “We lost a week in which we could’ve ascended,” he said.

Seated over ginger noodle soup that night from a street vendor in Pichari, he tried to cast the whole experience in a happier light. “The good part is that scientifically we found a lot of stuff, some beautiful new samples,” he said. Padial estimated that the expedition had yielded 14 species that are new to science, including an iguanid lizard with a sharp spiny crest, a beautiful green arboreal snake with a large bold black spot on each side of its head, and two species of Terrarana frogs belonging to a poorly known group that lives in leaf litter on the forest floor.

Peruvian biologist Giussepe Gagliardi and an arboreal snake during one of the daily specimen photo sessions.
Peruvian biologist Giussepe Gagliardi and an arboreal snake during one of the daily specimen photo sessions. Andy Isaacson

“It could’ve been a lot worse,” he conceded. “There could have been an accident. Someone could’ve fallen into the river.” Padial admitted to feeling relief after the team passed back through Marontuari without an incident, as he’d heard some unhappy residents were plotting to block his exit in protest.

The 30-minute helicopter flyover—offering a view of Vilcabamba’s rugged interior that few have ever witnessed—only whet Padial’s appetite even further. “I was like, ‘Wow, this is even more astonishing than I thought!’” he said over dinner. “The landscape is so much more impressive than you can see on the maps.”

Padial felt that despite falling short of his goal—a comprehensive inventory of reptiles and amphibians of the Vilcabamba from top to bottom—the expedition had demonstrated, or perhaps confirmed, something important: the Vilcabamba Range is home to many new species and many more awaiting discovery. This knowledge, he hoped, might motivate other researchers to search the area for different kinds of organisms, and over time, raise the profile of Otishi National Park as a place of unique and extraordinary biodiversity—a place worthy of future protection.

Padial’s team managed to walk out of the jungle with a bunch of specimens and tissue samples, as well as audio and video recordings, of very rare species that had never been recorded, photographed, or analyzed genetically before. All of that novel material would eventually be deposited in public collections and made available to anyone. With it, he and other researchers could begin building phylogenetic trees of species from the Vilcabamba Range, inferring when these animals split from relatives, how environmental changes have affected them, and how they got there in the first place.

The Vilcabamba Range, one of South America’s most pristine mountain ranges.
The Vilcabamba Range, one of South America’s most pristine mountain ranges. Andy Isaacson

Padial also believed that his efforts made a case for the value of going out and traipsing through nature in search of novel organisms—for the merit of old-fashioned fieldwork—at a time when our collective attention, and funding for science, has pivoted toward endeavors deemed relevant for technological progress: robotics, gene sequencing, and the like.

“We can tell the scientific community to leave their comfy chairs and do more fieldwork—and provide more funding for it—because we’re far from knowing what’s living out there,” he told me. “If you can still go to a place so close to a paved road and find 10 to 14 new species of frogs and reptiles in a couple of weeks, imagine how much there is still to do.”

And of course Padial continues to heed the call himself. Shortly after returning to Pittsburgh from Peru, in early March, he emailed to say that he’d already managed to secure funding to go back to the Vilcabamba in 2017.

“This time during the dry season,” he added.

This story originally appeared on bioGraphic.