The dense treetop canopy plunges day into night as we enter the rain forest. We are about 300 miles north of the Equator, in the Central African Republic, and the jungle vibrates with the haunting shrieks of insects as we clamber over fallen logs and step around giant trees strung with thorn-studded vines. Lurking overhead, I am told, are cobras. Leading the way is Babangu, a Pygmy tracker. He is followed by two tall Bantu paramilitary guards, clad in camouflage and toting AK-47 assault rifles. David Greer, a 35-year-old American who leads the anti-poaching patrols, is armed with a 9 millimeter pistol.

Shotgun shells litter the animal paths. "They’re fresh, the poachers have probably been here today," Greer whispers. I gulp with fear, knowing that the poachers carry AK-47s and elephant guns. Babangu points to a poacher’s snare—a wire loop buried in the fallen leaves and attached to a bent sapling. Greer snips the wire and uproots the trap.

Babangu leads us to a red duiker, a dog-size antelope, caught in a snare. It’s dead. "This could have been a gorilla, a chimp or a leopard," Greer whispers as we squat by the body. His eyes harden as he sees that the duiker had almost torn off a front leg trying to free itself from the trap.

We leave the animal in search of more snares. In two hours walking the jungle, we find another 171. Greer and his 48 men have destroyed more than 30,000 of the illegal devices in the past year, putting a big dent in the poachers’ haul of forest animals. But Greer knows that much more needs to be done.

Later, on our way back, we pass by the spot where the duiker had been snared. The carcass has vanished. Greer grimaces. "The poachers must have been nearby," he whispers. "If we’d stumbled on them, there could have been shooting."

Illegal hunting is devastating wildlife across sub-Saharan Africa. "The African bushmeat trade is huge," Jane Goodall, the distinguished primatologist (and Greer’s mentor), told me in an e-mail. "Tons and tons of wild animal meat [are] trucked into the urban centers, and a good deal is shipped to other African countries and to other continents."

A study in the journal Science this past November said the bushmeat trade was among the "greatest threats to the persistence of tropical wildlife." The researchers—from England, Ghana, South Africa, the United States and Canada—found that increased hunting of wild animals in Ghana had led to sharp declines in 41 species. They went on to suggest that the bushmeat trade had grown partly in response to the depletion of fish off West Africa by foreign and domestic industrial fleets; deprived of a traditional protein source, people turned to the forests for food. To curb the traffic in bushmeat, the researchers called for both limiting "the access of large and heavily subsidized foreign fleets to fish off West Africa" and "increasing the size, number and protection of wildlife reserves."

In the Congo Basin—an area consisting of the Republic of the Congo, the Democratic Republic of the Congo, Cameroon, the Central African Republic (CAR), Gabon and the Republic of Equatorial Guinea—some researchers estimate that up to five million metric tons of bushmeat are traded each year, according to the Bushmeat Crisis Task Force, a Washington, D.C.-based conservation consortium.

Another threat to wildlife is infectious agents, including the deadly Ebola virus, which has stricken primates in central Africa. It also poses a danger to people who eat or come into close contact with infected animals; some experts say that Ebola-contaminated bushmeat smuggled into the United States could trigger an Ebola outbreak here.

All told, the number of western lowland gorillas in the Congo Basin has fallen from about 110,000 to fewer than 40,000 in the past two decades because of poaching, loss of habitat to logging and development, and disease, says Richard Carroll, director of an African program for the World Wildlife Fund (WWF): "It’s a crisis situation, and that’s why the anti-poaching program is vitally important."

Greer risks his life virtually every day to protect some of Africa’s most significant animals, including western lowland gorillas and forest elephants. He is based in the Dzanga- Sangha Dense Forest Special Reserve, home to one of the richest and most diverse assemblies of animals, birds, fish and insects on earth. The 1,220-square-mile sanctuary in the CAR connects with protected forestlands in Cameroon and the Democratic Republic of the Congo, forming a 4,000- square-mile wilderness reserve overseen by the three governments with financial help from the WWF and the German Development Agency. Greer is employed by the WWF as a park adviser and empowered by the CAR government to enforce anti-poaching laws. Aprimatologist who had previously never wielded anything more lethal than a ballpoint pen, he’s one of a new breed of eco-warrior who carries a gun in the fight against the slaughter of forest animals.

To reach this embattled tropical treasure, I fly from Paris to Bangui, the capital of the CAR, a landlocked country of about 240,000 square miles—slightly smaller than Texas—tagged by the World Bank as one of the world’s poorest nations. Bangui is a tragic and frightened city, its residents cowed by decades of violent coups d’état by officers of a ruthless national army. Nestled against the Oubangui River, Bangui is a hot and humid relic of French colonialism littered with run-down buildings, potholed roads and crumbling monuments to former dictators. Surly police carrying clubs prowl the streets. Soldiers toting assault rifles and manning antiaircraft guns tear through the city in trucks escorting the country’s military ruler. Foreign visitors mostly stay in one of several hotels that look as if they belong in a Graham Greene novel, their lobbies the haunt of shady characters whispering in Sango, the local language, and French. The hotel swimming pools are thronged by frolicking prostitutes, some as young as 12.

In the city’s central, open-air market, Bantu women clad in colorful robes sell piles of smoked bushmeat—mostly duiker, Greer says, but occasionally great apes and elephants. To local residents, one of the main appeals of bushmeat is low cost; Greer says he has seen smoked gorilla meat selling for as little as 25 cents a pound in a village market. People who have traditionally lived off the rain forest view hunting and trapping as their prerogative, especially in the poorest areas. "Because they are very poor and have a difficult time finding jobs, they feel they should have the right to utilize the forest," says Pascal Dangino, a former poacher who now works for Greer as a guard. "Conservation is a difficult concept for them to understand."

I leave Bangui by SUV to get to the Dzanga-Sangha forest reserve about 300 miles to the southwest along a bone-shaking dirt road. I am accompanied by Angelique Todd, an English wildlife biologist who studies gorillas, and along the way we pass a handful of impoverished towns brimming with men and women playing cards, sitting by the road chatting and dozing in the sun. Nearing the reserve, I spy the igloo-shaped huts of the Bayaka Pygmy clans, who have inhabited the Congo Basin for more than a millennium. Masters of the rain forest, the Pygmies are among Greer’s most valued allies.

Greer, wearing shorts and going shirtless and barefooted, greets me at his spartan wood bungalow in Bayanga, a village on the Sangha River at the republic’s southernmost
tip. We had met seven years earlier in Rwanda, where he was studying mountain gorillas with the Dian Fossey Gorilla Fund International. "Hop in," he says, opening the door of a mud-splattered SUV. "Let’s go see some gorillas."

As we drive through Bayanga, men and women wave, and smiling children run alongside the truck calling out, "Darveed." He returns their greetings in Sango. In the seven years he has lived here, he has clearly made an effort to blend in. "They know I like to live with them and eat their food, enjoy their culture and play basketball with them," he says.

On Bayanga’s outskirts we enter a dense rain-soaked jungle, and a sign featuring a painted gorilla shows that we have reached the reserve’s crown jewel, the 470-square-mile Dzanga-Ndoki National Park. Greer tells me the park is inhabited by 88 species of mammals and 379 species of birds, including many rare creatures hunted by poachers. "All fishing, gathering, hunting, mineral and forest exploitation are prohibited in the park, which is a vital reservoir for endangered species," he says. Native Africans, he adds, are allowed to hunt, fish and gather plants outside the national park, in the Dzanga-Sangha Dense Forest Special Reserve.

The farther Greer goes into the park, the wider he smiles, but then, he believes he was born to a life in the wilderness, despite his city roots. Raised in Kansas City, he says he was something of a street fighter as a youth. His father, a lineman for Southwestern Bell Telephone Company, took him fishing, hunting and camping. Greer won a baseball scholarship to Baker University in Baldwin City, Kansas, where he studied psychology; after college, he worked briefly as a psychologist in a mental health clinic in Kansas City. But in 1994 he abandoned psychology to work with chimpanzees at the Jane Goodall Institute for Wildlife Research, Education and Conservation in Tanzania. Refused a resident’s visa, he moved to Karisoke in Rwanda, the mountain gorilla research center founded in 1967 by Dian Fossey.

Greer well remembers the first mountain gorillas he ever saw, a silverback that Fossey had named Pablo and six females with their young, chomping on nettles and other plants on the slope of a volcano in Rwanda. "I felt like the luckiest human being on earth. I felt I was meant to be here, this was my calling," he says. "Every time I saw the mountain gorillas after that, my stomach would tighten with emotion. They’re so big and beautiful, and yet so peaceful."

Greer had arrived in Rwanda after the Interahamwe— gangs of extremist Hutus—had shocked the world by killing up to nearly a million rival Tutsis and moderate Hutus. He often came across the marauders’ fresh trails along the mountain slopes and saw armed Interahamwe in the distance. "There were bodies all over the place," he remembers. Once, while he was observing foraging gorillas, the animals came across a dead Hutu riddled with bullets. "The gorillas glanced at the body, then stepped around it," he says.

He continued to study the animals, driving an hour a day from the small city of Ruhengeri to the foot of the Virunga volcanoes, then hiking up to four hours into the forest where the gorillas lived. "I felt someone had to be with them every day to make sure they weren’t harmed," he says. His work was finally disrupted when the Interahamwe began executing foreigners. In January 1997, gunmen stormed into Ruhengeri and fatally shot three Spanish doctors and wounded an American aid worker. The next day, Greer left for Kigali, the capital, and he says he stayed "until the rebels were eventually flushed back into the Democratic Republic of the Congo."

Several months later, Karisoke temporarily suspended the monitoring of gorillas, and Greer moved again, to a swampy jungle straddling the Republic of the Congo-CAR border. There he studied western lowland gorillas at Mondika, a research station run by Diane Doran, a physical anthropologist at the State University of New York at Stony Brook. Greer, who would later serve as Mondika’s director for two years until 2001, was intrigued by the differences between mountain gorillas and the western lowland species—the kind most commonly seen in zoos. Mountain gorillas forage in family groups along lush alpine slopes for wild celery, thistles, shoots and occasionally bark and insects. In contrast, lowland groups seek the leaves and sugary fruit of high jungle trees, shinnying up with astonishing agility to balance on boughs while they strip the branches. Also, Greer says, compared with mountain gorillas, the lowland animals "are much shyer, and are hard to find because they are hunted for food and travel much farther each day."

While visiting the Dzanga-Sangha reserve’s headquarters at Bayanga, Greer sometimes encountered Chloe Cipolletta, a vivacious young Italian wildlife biologist and gorilla researcher. The daughter of an Italian banker, Cipolletta, 34, could have lived in a luxurious Roman villa and been courted by sleek Armani-clad young men. Instead, she has made her home since 1998 in a thatched hut at her base camp in Bai Hokou. (A bai is a forest opening with a water source that attracts wildlife.) In July 2001, three years after Greer and Cipolletta met, they were married in a Pygmy wedding ceremony beneath the high trees at Bai Hokou. Following the custom of the diminutive forest people, the newlyweds exchanged sticks—the significance of the ritual was not explained to them—and then celebrated with the Pygmies, singing and dancing until noon the next day. "Pygmies are inexhaustible when it comes to partying," Greer says.

An hour after leaving Bayanga, we reach Bai Hokou, a huddle of thatched huts on a heavily forested hill and surrounded by a wire barrier hung with tin cans that frighten off forest elephants when they run into the fence. Cipolletta, standing at an outdoor table, is separating gorilla dung with twigs to determine what fruits the apes had been eating— information that becomes increasingly important as gorilla habitat disappears. She has counted more than 100 plants they use as food. When I ask her about Greer, she says, "He’s my Tarzan. He likes to climb trees and is the first to try anything."

"Does that mean you’re his Jane?"

"No," she says, laughing. "I’m his Cheetah."

Based at the camp with Cipolletta are several Pygmy animal trackers and three research assistants, including two 26- year-old Americans, Jessica Zerr and Sarah Pacyna. Zerr, a Californian, found the work hard at first and has had four bouts with malaria. But she never despaired, she says: "To be with the gorillas was my life’s dream."

The next morning, Greer and I leave with Ngbanda, a Pygmy, to find a gorilla group that he and Cipolletta have "habituated," or spent so much time observing that the animals have become accustomed to human beings. As a barefooted Ngbanda leads us along a path carved by the feet of generations of forest elephants, the rain-speckled jungle presses in from all sides, exuding a dizzying odor of dank earth and foliage. We push past tree branches blocking our way, shuffle through streams and duck away from djele— vines studded with thorns that festoon the tracks. Tiny, stingless sweat bees swarm us, buzzing around our ears and mouths and dive bombing our eyeballs.

Suddenly, Ngbanda halts. "Elephant," Greer murmurs. In the shadowy foliage I spy a trunk and tusks. Compared with plains elephants, forest elephants tend to live in smaller herds, thanks partly to their dense, tangled territory, and they also are smaller in size. Still, at some eight feet high and three and a half tons for a mature bull, forest elephants are formidable. "Run like hell if he charges, because they hate humans, with good reason," Greer whispers. Thankfully, the elephant ignores us.

Two hours later, as we push through a bamboo thicket where the air is so humid it seems to sweat, Ngbanda halts us. "Ebobo," he mouths. Gorillas. Greer and I see nothing, but he trusts the Pygmy trackers. "They seem to have X-ray vision," he says. "They see and hear things in the jungle that we can’t."

Ngbanda points at a giant tree. About 50 yards above us, almost hidden by the foliage, a potbellied female feasts on fruit, while below her an infant nestles on another branch chewing leaves. Moments later we hear, somewhere in the thicket, the thock-thock-thock of a silverback pounding his barrel chest in warning. Ngbanda spies him about 15 yards ahead and drops to the ground, followed by Greer and then me. "Makumba," Greer whispers, identifying the animal by name. We crouch to mollify the huge ape, a primate gesture of humility and respect that silverbacks understand, indeed expect.

Moments later, Makumba disappears. Listening to gorilla sounds that Greer and I cannot distinguish, Ngbanda plots the path of the silverback, and we follow through the undergrowth and down an elephant track. Suddenly, Makumba leaps onto the track about ten yards ahead, his huge furry face scowling. With a forearm as big as a man’s thigh, he slams a bunch of saplings repeatedly against the ground. "He’s displaying his authority over us," Greer says, "warning us not to come closer." We steer clear of him and don’t see him again.

That night, back at Bai Hokou, I use the camp’s "shower"— a spring-fed waterfall that feels delightfully cold—and then rejoin Greer and Cipolletta. I ask him what made him take up arms against the poachers a year ago. He says he and Cipolletta had been hearing gunshots for days on end and knew from the Pygmies that poachers were slaughtering large numbers of elephants, gorillas and other animals. The couple had also seen lots of bushmeat in the Bayanga market. And they knew that the leader of the anti-poaching patrols had quit and that the guards had become "demotivated," as he puts it, "and had a sense of helplessness with the barrage of poaching."

So last October, Greer accepted the challenge. With the help of his deputy, Josue Nambama, a well-connected Bantu, he concentrated on building a network of sources to provide information on the poachers. (I saw several men approach him at the village soccer field or at his home to provide information, sometimes for a small reward.) He also hired new guards, putting one team on alert 24 hours a day and assigning another to find and destroy snares. In addition, guards set up roadblocks to catch bushmeat traders and patrol animal- rich areas in the reserve, up to ten days in the field at a time. It is dangerous work. On one snare patrol, guards and poachers stumbled on each other, and in the confusion, a poacher who shot at the guards missed and killed one of his own porters. Because the anti-poaching effort is short on funds, guards are heavily outgunned by poachers, having just four AK-47s and seven old Russian bolt-action rifles. Many guards go on patrol armed with only their bare fists. Greer and Nambama’s efforts have led to the arrest and imprisonment of 20 poachers and discouraged dozens more. A CAR forestry and sustainable development official, Jean- Bernard Yarissem, says bushmeat has become noticeably less available in the Bayanga marketplace since Greer took over the anti-poaching effort. Jean-Rene Sangha, once the reserve’s most notorious elephant killer, says, "Before, there were many poachers, but with David’s arrival poaching decreased very much."

When I first met Sangha, whose parents named him after the nearby river and who now works with Greer as a guard, the wiry 26-year-old stared at me and said he’d begun to learn the poacher’s bloody trade at age 10 from his older brothers. He said he has slaughtered many gorillas—silverbacks, females and young—for bushmeat. He also admits to having killed "more than 100 elephants." Flaunting a devil’s courage, Sangha shot the elephants at point-blank range, then smuggled the tusks across the border into Cameroon. "Before, the price of one kilo of tusk was 8,000 CFA [about $15], but now one kilo costs 12,000 CFA [about $22]," he says, the market having inflated due to scarcity. With a pair of exceptionally big tusks weighing about 60 kilos, the 720,000 CFA (about $1,400) would keep a family in Bayanga for more than a year. Selling the elephants’ meat was a bonus.

Sangha, who says he lost two brothers in poaching acci dents, approached Greer about working with him on the patrols. Greer offered him a guard job at about 90,000 CFA a month, or more than twice a laborer’s wage. Sangha accepted. "I’ll help the other guards because the forest is very large and I know how the poachers work," he says. "I was a poacher, I know how to struggle against poachers." after poaching, the threat to the Congo Basin’s gorillas that most concerns Greer is Ebola, the highly infectious hemorrhagic fever virus that was first recognized in human beings, in central Africa, in 1976. The virus is passed on by direct contact with victims’ tissues or body fluids, and kills up to 90 percent of people infected. No cure for the disease exists, and many sufferers die quickly and horribly with massive internal and external bleeding. Ebola virus infects gorillas and other nonhuman primates with similarly lethal effects. Arecent Ebola outbreak in the Republic of the Congo killed up to 90 percent of the gorillas in some areas; at Lossi Gorilla Sanctuary, 139 out of 145 gorillas died from Ebola, Greer says.

The disease poses a threat to the Dzanga-Sangha gorillas. "It’s now been reported at the Congo’s Odzala National Park, which has Africa’s highest density of gorillas," Greer explains. "That’s less than a few hundred miles away in a contiguous forest with some barriers, but nothing too extreme to be able to block it." Not long ago, he and Cipolletta arranged a meeting of local health officials and village chiefs, and urged them to warn their people not to slaughter or eat monkeys, gorillas or chimps. "That’s how it spread in the [Republic of the] Congo," he says, meaning that people acquired the disease from handling an infected primate and passed the virus to others.

Some experts are concerned that bushmeat tainted with Ebola virus or other infectious agents might be smuggled into the United States. "Thousands of west and central Africans live in Florida, California, New York, as well as Atlanta and many other cities, and when they celebrate weddings, birthdays or other occasions, [many] want to eat bushmeat from their homeland," says Richard Ruggiero, an Africa program officer for the U.S. Fish and Wildlife Service. "Because its entry is illegal, it’s smuggled in as other meat or is brought in undeclared by travelers." Most of the smuggled bushmeat confiscated so far, says Ruggiero, has been cane rat, a two-foot-long field rodent weighing up to ten pounds, but other wild meat has also turned up.

In 2002, customs officials at the Hartsfield-Jackson Atlanta International Airport found a smoked primate carcass in the suitcase of a passenger from Cameroon; the passenger was reportedly carrying the bushmeat to a traditional wedding celebration. Inspectors at other U.S. airports have also reported a recent rise in seizures of African bushmeat, including a 600-pound shipment in 2003 of duiker, squirrels, bats and rats hidden beneath dried fish at New York City’s JFK International Airport. The same year, a shipment of 2,000 baboon snouts bound for the United States was seized at Schiphol Airport in Amsterdam. "We have only 100 inspectors across the United States, and so it’s scary because we’re certainly only seeing the tip of the iceberg with bushmeat," says Mike Elkins, a U.S. Fish and Wildlife Service special agent in Atlanta.

Trish Reed, a Wildlife Conservation Society field veterinarian who has done research at Bomassa in the Republic of the Congo, is arranging to test primate carcasses for Ebola virus at a lab in Libreville, Gabon. She says the danger of Ebola getting into the United States by means of infected bushmeat is currently low. "Smoking the meat almost certainly kills any Ebola it might have," she says, "but we are not 100 percent certain." Indeed, in 2003 the U.S. Centers for Disease Control and Prevention warned of the dangers of prepared bushmeat, saying that "smoking, salting, or brining may slow down bushmeat’s decay, but may not render bushmeat free of infectious agents." The Ebola threat, whether to primates directly or to people exposed to the infected animals, has added urgency to conservation efforts: saving gorillas could also mean saving human lives. Nearing dusk one day, Greer strides barefoot through the jungle heading for Dzanga Bai, the reserve’s most spectacular forest opening. He is carrying a pack of red wine, cheese and baguettes for a monthly ritual. At the bai, a sandy salt lick the size of three football fields, 75 forest elephants have gathered, part of a recent resurgence that some attribute to Greer’s efforts. Researchers have identified more than 3,300 elephants using the bai.

Cipolletta has gotten there first, and now the couple climb to a tree-high platform to watch in safety. As calves scurry alongside their mothers, a pair of young bulls jostle for dominance by locking tusks and shoving hard. Ignoring the ruckus, other elephants kneel by the mineral-rich water and drink. Calves wallow merrily in the mud until they look like chocolate elephants. Darkness arrives and a full moon turns the forest opening a ghostly silver. Greer and Cipolletta settle in for the night under their mosquito nets as the elephants’ growling, rumbling, screaming and trumpeting echo around the bai. "Every time I’m at the bai," Greer says, "it’s a magnificent feeling, and it gives me a sense of optimism that there is the chance to have some long-term success."