Scientists Race to Uncover the Secrets of Madagascar’s Treasure-Filled Forests

We had come this far and now we were stuck, dug in on a dirt track high above the plains. It was monsoon season in Madagascar, and thunderstorms had laid waste to the deeply rutted road. Already we had traversed seemingly unnavigable passes on our way to the remote northern mountains, mud churned to slurry by each passing set of wheels. Almost 24 hours later, this slope flanked by agave plants had defeated us. Our drivers took up shovels: There were ruts to flatten, boulders to excavate and heave into the bushes. As the workers toiled, cicadas hissed from the treetops.

For the field biologists I was accompanying, this breakdown of rural infrastructure held great promise. They were on their way to survey some of the island’s last remaining virgin rainforests—shrinking havens of exceptional biodiversity, including some of Earth’s rarest birdlife. “There’s definitely a correlation with how hard it is to get in,” said John Mittermeier, an expedition leader, ornithologist, and geography Ph.D. student at Oxford University, “and how likely you are to find new stuff.”

Now a cry went up among the team. A snake was moving its way through the undergrowth, and with abandon they leapt after it. Luke Kemp, the herpetologist on the expedition, crouched beside the bushes, poking around but coming up empty. “It’s like an addiction,” he told me. “I can’t stop.”

The biologists had congregated from four countries, united by a relentless, even maniacal fascination with wildlife. They wore faded shirts from scientific conferences and were never without their binoculars. Instead of making small talk, they discussed bird calls and sampling methods, animated by purpose and shared expertise. In unison, like meerkats, Mittermeier and the other two birders swung their binoculars from side to side, trying to glimpse what sounded to them like an endemic robin. The two entomologists swept the air with butterfly nets; they would not hesitate, when their hands were full, to pop wriggling insect specimens between their lips.

Lily Arison Réné de Roland stood at the roadside, watching his younger colleagues with amusement. The renowned Malagasy ornithologist has the demeanor of a monk—easygoing and completely bald, often resting his hands on his ample belly. For half his life he has worked for the Madagascar branch of the Peregrine Fund, a U.S.-based conservation nonprofit, becoming national director in 2004. In 2006 he stunned the birding world by locating a flock of Madagascar Pochards, an endemic diving duck thought to have gone extinct in the early 1990s.

Through this rediscovery, Réné de Roland had secured government protection for two forest tracts where he found the pochards, comprising some 435 square miles of threatened habitat. Since then, one reserve, Bemanevika, has been extensively surveyed, revealing breeding populations of serpent eagles and red owls, as well as the bizarre-nosed chameleon, a reptile species new to science with a corneous, knobbled beak. But the larger, more isolated reserve, Mahimborondro, has never been thoroughly explored.

Hope is like oxygen for conservationists, and it seemed likely that these remote areas harbored further biodiversity riches. Over the next two weeks we would trek into the forest’s depths, drenched by rain and assailed by leeches, to collect as much information as possible about the animals that lived there. The scientists might discover new species; many of them had made such finds on previous expeditions. But this was not the main purpose of their work. With better scientific data, people like Réné de Roland would be able to better manage the reserves and argue for their continued protection, amid demands to open up more lands for agriculture.

Our drivers reshaped the road enough to make it passable, and at last we arrived at the research station in the Bemanevika reserve, a clutch of wooden shelters and weather-beaten tarps built by the Peregrine Fund in 2009. It had taken us eight hours to drive 30 miles, a speed only marginally faster than walking; from here our journey would continue entirely on foot. We piled out of the vehicles into a lush forest clearing. A cacophony of frogs and birds rose to greet us. “Rainy season makes it difficult to get here,” said Réné de Roland, a knowing smile on his lips, “but it’s worth it.”

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or the student of nature, Madagascar has few equals. More than 80 percent of its plants and animals are globally unique. Geographically isolated for 88 million years, the island, roughly the size of Texas, evolved ecosystems of spectacular richness, bringing into existence the lemur, the fossa, and more than 100 endemic birds. “It is a treasure trove,” wrote the late British naturalist Gerald Durrell in 1992. “If the mysterious forests are left intact and explored carefully, new and astonishing species are still to be found.”

Between 1999 and 2010, scientists described more than 600 new species from Madagascar, including the Tsingy Wood-Rail, a furtive bird that skulks on the forest floor. There were 11 types of chameleon and 41 mammals, among them a ferocious, weaselly creature named after Durrell—the world’s first new carnivorous mammal to be discovered in nearly 25 years. Also hiding in plain sight was a massive palm tree that self-destructs after flowering, and the world’s smallest primate, a lemur weighing just one ounce. Visiting Madagascar for the first time, said Dale Wright, a South African ornithologist jointly leading our expedition, was “teenage-dream bucket-list stuff.”

But just as the island is a source of wonder for biologists, it is also a source of despair. Many newly described species are already endangered at the time of their discovery. Countless others, from Elephant Birds to Madagascan dwarf hippopotamuses, have already disappeared. Nearly 700 different orchids—more than three times the number found in the United States—are presently considered threatened.

Extinction is a global tragedy, but in this crucible of unique species, the stakes are even higher. Organisms lost to Madagascar are lost, irrevocably, to the world. And so, like the Amazon rainforest and other biodiversity hotspots, Madagascar holds outsized significance among conservationists, who often watch helplessly as its resources are stripped away.

Madagascar’s government has pledged support for conservation efforts, more than quadrupling the size of its protected-area network since 2003 to more than 17 million acres, but faces the unyielding economics of a profoundly poor nation. Most of the island’s inhabitants eke a living from subsistence agriculture, maintaining their pastures by slashing and burning forest; logging is also a grave threat. Tree cover has declined by an estimated 90 percent, much of it in the past century. In 2017, deforestation reached a record annual high of nearly 2,000 square miles—nearly one percent of the country’s land cover.

Much of the journey north from Antananarivo feels like passing through a mining wasteland, the destruction stemming from agriculture and liberal use of fire. Red scars disfigure the earth where topsoil has eroded; in places, as if ripped into by colossal machines, entire mountainsides have fallen away. The long-horned cattle known as zebu—­indigenous to South Asia, like the island’s first human ­inhabitants—graze across the plains, treading between bright green rice paddies. The area under cultivation for rice, Madagascar’s staple crop, has more than doubled since 1970, encroaching on wetlands and forest.

It was just north of one of the island’s biggest rice-producing regions that Réné de Roland stumbled on the pochard in 2006. He was conducting a nationwide survey of the Madagascar Marsh-Harrier, when he saw two of the endangered raptors circling high above the mountains. He hopped in his car and pursued them. In a single day he counted 22 near the village of Bemanevika (now located within the eponymous reserve). Surprised to find a good forest block, he returned and set up camp beside an ancient volcanic lake called Matsaborimena. Within hours of arriving, Réné de Roland saw a flock of pochards paddling on the water. He was shocked; raptors were his expertise, but he instantly recognized the birds in front of him and knew they weren’t supposed to exist.

Chocolate brown in color, with white-ringed eyes, the ducks were once abundant in wetlands farther east, but habitat loss, hunting, and the introduction of predatory fish that outcompeted the ducks sparked precipitous declines in the 1940s. The last confirmed sighting was in 1970, and in 1992 a pochard thought to be the last of its species died in a zoo.

Within a year of Réné de Roland’s discovery, the entire pochard population was estimated at just 13 individuals, all confined to three volcanic lakes nearby. The species soon became known as the world’s rarest duck. Capitalizing on the flood of interest around the globe, Réné de Roland raised international funding and by 2015 had secured full protected status for the surrounding forest, adding the Mahimborondro reserve soon afterward. “It’s incredible what he’s achieved,” Mittermeier said. “He’s extremely well connected, both internationally and to the government.”

Réné de Roland also helped set up an ambitious captive-breeding project in Antsohihy, the regional capital, partnering with the federal government and several other conservation groups. By 2019 the captive population had swelled to nearly 100 individuals, and more than 20 had been reintroduced to the wild at another lake farther east (though they still require supplemental duck food flown in from England).

On our first day at Bemanevika, Réné de Roland led us to the site of his discovery: a smooth, muddy lake encircled by forest. Local technicians rowed us in canoes to get a closer look at our quarry, which paddled along the opposite shore. The ducks seemed rather ordinary to me—nothing like the flamboyant Mandarin that arrived in Central Park last year and went viral on social media, for instance. But just because a creature is rare does not mean that it must look spectacular: The Ivory-billed Woodpecker has vanished from this Earth, but so has the Dusky Seaside Sparrow.

To Mittermeier, standing beside the lake, the ducks represented something of a psychological boost. He was born into a family of celebrated environmentalists—his father, Russell, was a president of Conservation International—and began conducting his own field trips as a freshman at Yale, searching for rare birds in Western Samoa, Suriname, and the Solomon Islands. In 2015 he made the Forbes 30 Under 30 list for his contributions to ornithology, which include discovering what could turn out to be three undescribed taxa of birds. Still, he said, conservation could feel like “arranging deck chairs on the Titanic—you’re basically just chronicling things that are going extinct.”

And so he sometimes liked to imagine a poster of the Madagascar Pochard on his wall, he said, as motivation to persevere. “You think of the duck as the catalyst to conserve this whole area and this whole suite of species,” Mittermeier told me. “And of Lily making it all happen. It’s insane.”

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gregarious lemur lived among the trees at the Bemanevika field station and would descend to accept bananas from the staff. Several mornings I awoke in darkness to it bouncing on my hammock ropes; when I stirred it would race away and glare at me. I became grateful for these visits, which served as a sort of alarm clock: We set off before dawn each day to cover as much ground as possible before the afternoon rain. Often we were caught and trudged soaking across the grasslands, optimistically hanging our clothes to drip dry once we returned. But in the monsoon season nothing dries, merely regresses toward wetness, as if following some inviolable law of thermodynamics.

The scientists shrugged off any discomfort, walking miles each day to collect frogs and rare insects. Robin Colyn, a researcher with BirdLife South Africa, scoured the surrounding wetlands for the Slender-billed Flufftail, a tiny brown rail with a straight, glossy beak that is considered one of the world’s most secretive and poorly understood birds. It has begun vanishing across the country as rice paddies have encroached on its marshland habitat. Colyn almost wept with joy when, with the help of the technicians, he flushed several birds into the open and caught them. Holding them tenderly, he drew blood samples for studies that will help reveal the health of the population.

One morning we went looking for a resident Madagascar Red Owl, led by a Malagasy Peregrine Fund technician named Moïse. About 25 years ago Réné de Roland encountered him climbing trees as a young man and recruited him as an assistant. Now Moïse, who doesn’t use a surname, expertly shimmied up to the roost and retrieved the bird. The species was first described in 1876, but was barely seen for more than a century until its rediscovery in 1993. The pale owl twisted its neck silently from side to side, looking irritated as we stood reverentially around it.

We devoted another morning to finding the endangered Madagascar Serpent-Eagle. Réné de Roland had located a breeding population at Bemanevika soon after finding the pochards; until then the bird was thought to occur only in forests 100 miles to the east. Starting in 1992, he had spent thousands of hours there setting mist nets to try and catch the birds as they flew low beneath the canopy, hunting for chameleons and geckos. Finally, in 1994, he caught one, making the first documented sighting in more than half a century. It took him three more years to find a nest. Today, in Bemanevika and other forest blocks in eastern Madagascar, the Peregrine Fund radio tracks three pairs and monitors dozens more eagles. The bird’s numbers are likely declining in step with disappearing forests; fewer than 500 are believed to survive in the wild.

Moïse led us through burned fields into the forest, brandishing an antenna to track eagles fitted with radio tags. The tracker beeped as we marched, the rate quickening as we neared our unseen target. It was wet and murky after a night of rain; malarial mosquitoes swarmed around us. Then Moïse waved at us to stop moving. The beeps became a soundtrack of suspense. “We’re looking for a little dark spot against the sky,” one of the birders whispered to me. Someone trod on a twig. The biologists had their binoculars out, contorting their bodies upward. Their faces were grim, like soccer fans in a shootout. Finally Moïse spotted the eagle on its perch, obscured by a tangle of branches. “Yessss,” Mittermeier hissed, nailing a photo.

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e left for Mahimborondro, a hike of nearly 20 miles after a week at the field station. The reserve is less fragmented and extends to higher elevations than Bemanevika; together, with a couple of other preserves, they form a corridor toward lowland forest in the east. An army of porters hauled our equipment—young men from the surrounding villages, carrying loads in excess of 100 pounds. Their wage for this labor was less than $3 a day. In the context of a marginal subsistence economy, the money was sorely needed: Nearly 80 percent of all Malagasy live on even less. Still, it felt deeply uncomfortable, as if we were embarking on a colonial trek. “We might as well be wearing pith helmets,” one of the scientists said.

Even without a pack, I worried I wouldn’t make it. My knee had begun hurting at the field station; five miles into the hike, bad cramps set in. Like a column of ants, we marched up and down the slopes. Thunder­clouds broke, drenching us once more. Everyone else remained in high spirits, and as the day progressed I fell ever further behind. Limping through a thicket,

I saw a bug on a branch, quite possibly new to science, and indulged in hateful thoughts about the forest.

We made camp beside a lake in the soaking rain. The porters stayed up roaring with laughter, while I lay forlornly beneath my tarp. It felt like a ridiculous mood to sustain, so the next morning, with new resolve, I followed several biologists into the forest. Kemp, the snake addict, snatched frogs from the leaf litter. The Belgian entomologists, Merlin Jocque and Dan Slootmaekers, excitedly pursued invertebrates. Then Brett Gardner, a zealous wildlife veterinarian from South Africa, wandered over with a plastic tube.

“Is that a spider or is that not a spider?”

“Well, I think you just hit the jackpot,” Jocque said.

A little larger than a grain of rice, it had an erect neck and outsized downward-curving mouthparts that looked uncannily like a beak. Jocque told Gardner he was very likely holding a new species of pelican spider; Jocque was feverishly excited, even though, like many entomologists, he encounters new species all the time. “My fridge is filled with species that I haven’t been able to describe yet,” he said. Now he began peppering Gardner with questions: On what plant had he found the spider? How high? Were there more?

East of our campsite, shrouded in cloud, rose a massif of nearly 7,500 feet where no scientists, and possibly no people at all, had ever been. We hiked across the next day, following a trail opened by the porters. The gradient was punishing, the vegetation almost impenetrable. Swarms of leeches clung to the leaves, ready to attach and begin feeding; we were constantly picking them off, leaving thin trails of blood on our skin.

Once we made camp, Réné de Roland oversaw the unfurling of mist nets. For multiple days, from dawn until dusk, Peregrine Fund technicians extracted birds and transferred them to Réné de Roland, Gardner, and Moïse, who identified, measured, and banded them. When released, the birds flitted back into the canopy and vanished. They recorded more than 14 species in all, from the Madagascar Magpie-Robin—the same bird they had heard at the roadside driving in—to the Red-fronted Coua, a cuckoo with bright blue skin around its eyes.

In the meantime, Mittermeier and Wright began canopy surveys, trekking for hours with microphones and cameras. Birdwatching in the rainforest is more accurately bird listening, and from “random cheeps and chips,” they began picking out calls. Rufous-headed Ground Rollers gave short, fog-hornlike hoots, while Red-tailed Newtonias sang wiki-wiki-wiki-wiki. “We’re starting to know the neighborhood,” Mittermeier said. Together, the mist-netting and visual and aural surveys would provide a richer picture of the birdlife than either approach alone.

Kemp, meanwhile, was erecting a sort of toll plaza for small animals, stretching sheets of plastic in a line between wooden stakes. Every few feet he dug buckets into the ground: “pitfall traps” for catching whatever struck the barrier, ran sideways, and fell in. The pitfall of this method was that it captured mostly shrews, which voraciously preyed on other creatures and each other.

“Shrews are terrible,” Kemp muttered one afternoon, sorting through mutilated specimens.

At night, in a clearing beyond the camp, the entomologists fired up a generator and shone bright light on a large sheet. Moths flooded in from the darkness, glimmering like jewels against the fabric. Slootmaekers, a moth expert, picked off specimens by their thorax with his thumb and index finger; those he wished to keep he injected with ethanol, cupped until they stopped moving, and then secured in an wax envelope. Wright and Mittermeier stepped into the clearing, falling silent amid the hum of the generator. “For me,” Wright said later, “going into nature like this is akin to going to church.”

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he team covered the 40-mile hike out from Mahimborondro in a single day. Our clothes were sodden and smeared with dirt. The porters, laden with gear, marched at a superhuman pace. The path curled out from the forest and across the bare stubble of the hills, rising and falling endlessly; in places the surface, a hard, wet clay, was as slippery as ice. Moïse walked beside Réné de Roland, whose knees were troubling him. It was dark and pouring with rain by the time the village came into sight.

The scientists left Madagascar with a robust inventory of species. Kemp had collected dozens of promising reptiles and amphibians, including five possibly new to science. Among hundreds of invertebrates, Gardner and the entomologists may have gathered enough pelican spiders—four females and a male—to determine whether they had discovered a new species. The ornithologists, meanwhile, had recorded 62 avian species, including globally threatened species like Meller’s Duck and Madagascar Grebe.

Comparing the tally between the two reserves, surprises and differences emerged. The scientists found several types of birds, including the Red-tailed Newtonia, some 1,000 feet higher than their known range, making that higher-elevation forest a potential stronghold as climate change and development alter swathes of existing habitat. And several species were documented in one reserve but not the other, underscoring the importance of protecting both areas. A single expedition isn’t going to reveal the full extent of biodiversity that these forests hold, but already scientists are surer of their immense conservation value. “This is a start,” Mittermeier said near the end of the trip. “These are like Lego blocks for future research.”

Réné de Roland plans to use the surveys—the first of many to come—to try and ensure that the reserves remain untouched. While the government hasn’t loosened protections for the tracts, the forces held at bay are still lying in wait. Hunger for land and resources in Madagascar is gnawing, with rampant illegal harvesting in other protected areas farther south. A warming climate will open new land for rice paddies, adding pressure to forests previously too cold for the crop. In April a team of Malagasy and international scientists published a letter in the journal Nature Sustainability highlighting the urgency of safeguarding Madagascar’s biodiversity. Soon it will be too late.

Réné de Roland, Mittermeier, and the other expedition members have no illusions about the difficulties of conserving species in an age of ecological crisis. But they take solace and hope in knowing that, for now, Bemanevika and Mahimborondro have been spared. In this remote corner of Madagascar, rare raptors roost high in the canopy, flufftails lurk beneath marshland reeds, and the humble pochard, the duck that prompted it all, glides in increasing numbers across smooth mountain lakes.

This story originally ran in the Summer 2019 issue as “Treasure Hunters.” To receive our print magazine, become a member by making a donation today.