The BBC footage shot last year from a small plane over the rain forest of western Brazil resembles a scene from Avatar. The camera’s frame floats over tropical treetops to reveal a community of “uncontacted” Natives in a small clearing where smoke rises from thatched huts and men in loincloths, their bodies dyed red and black, gaze through the foliage and point their arrows at the massive metal bird flying above them.

The scene is as fascinating as it is otherworldly, like peering back through time at the origins of humankind. Yet the Eden the BBC crew filmed is threatened, as are most of the Amazon Basin’s approximately 80 to 90 isolated tribes, and the causes are as common as the rising price of beef and bread at the local supermarket, or the international demand for oil and tropical hardwoods.

Though uncontacted groups—peoples who have had almost no interaction with the modern world—are especially vulnerable, Native peoples across the Amazon are struggling to protect their lands, cultures and livelihoods from loggers, miners, farmers, ranchers, oil companies and major development projects such as hydroelectric dams and roads. Whereas South America’s Native peoples have formed hundreds of political organizations, which cooperate on national and international levels, those peoples who still live deep in the forest can hardly comprehend the number and magnitude of forces that threaten their traditional existences.

According to Survival International, a London-based organization that campaigns for Native rights around the world, 6 million people have watched the BBC footage since it was released in early February 2010. In 2008, Survival International had distributed photos of the same community, which Brazilian anthropologist José Carlos Meirelles discovered two decades ago. Meirelles, who recently retired from his job running the national program to protect isolated peoples at Brazil’s Indian affairs agency, Fundação Nacional do Índio (FUNAI), guided the BBC to the community in order to raise awareness of their situation. He has noticed that uncontacted Natives from nearby Peru have moved into the area in recent years, probably to escape logging operations in the neighboring nation, and fears that this could result in tribal warfare over land. “The group in the film face the same dangers as uncontacted tribes throughout the Amazon Basin,” said Rebecca Spooner, who works on Survival International’s Latin America campaign, adding that the Natives who are moving into the area from Peru are fleeing logging operations near the border.

“Uncontrolled contact is very dangerous for these people,” said Spooner, who explained that loggers and other outsiders often carry diseases to which uncontacted Natives lack resistance, including malaria, measles and even the common cold. She cited the case of Peru’s Nahua tribe, which was first contacted in the 1980s by workers exploring for Shell Oil. A short time after that unwelcome introduction, more than half the tribe was wiped out by diseases.

Spooner noted that more than 70 percent of Peru’s Amazon region is now covered by oil concessions, many of which are superimposed on Native lands. Survival International is consequently collecting signatures for a petition asking Peruvian President Alan García to halt logging operations and oil exploration in areas with uncontacted tribes. “Survival International is calling on all governments to respect the right of uncontacted tribes to remain autonomous,” Spooner said.

The Amazon Basin is home to most of the world’s remaining uncontacted tribes, who are more accurately called “people living in voluntary isolation,” since many had contact with non-Natives decades or generations ago but fled deeper into the wilderness to escape violence, diseases or slavery. The vast majority live in Brazil, which holds 64 percent of the Amazon rain forest and has set aside almost 40 percent of that wilderness as indigenous territories and protected areas.

Conrado Octávio, a Brazilian geographer with the NGO Centro de Trabalho Indigenista, explained that since 1988, the Brazilian government’s policy has been to prevent contact with isolated tribes, but FUNAI is unable to stop the advance of loggers and settlers into Native lands. He noted that the government has improved its protection of isolated peoples in the past decade, increasing FUNAI’s budget and opening new lines of communication with Native organizations, but state support of agricultural expansion and mega projects increases the pressure on Native lands. “It’s a paradox. There has been a lot of progress, but pressure on indigenous lands is only going to increase because of the country’s macroeconomic policies, and not just on the lands of isolated tribes,” he said.

Octávio works on one of a dozen “ethno-environmental protection fronts” FUNAI has created to demarcate and monitor reserves where isolated tribes are threatened. Octávio works in the vast Vale do Javari reserve, on Brazil’s border with Peru, which has the greatest concentration of isolated people in the world—approximately eight tribes with an estimated total of 4,000 people. Though Brazilian loggers and farmers are advancing toward the reserve’s southern border, Octávio said the greatest threats are across the border in Peru, where Native lands are relatively small and surrounded by logging and mining concessions. “I’m not saying that all the threats are coming from Peru. We also have plenty of problems here in Brazil. But when the other side of the border is lined with logging concessions and oil concessions, it can’t be good for the isolated tribes,” he said.

According to Carlos Soria, an environmental lawyer with the Peruvian organization Instituto del Bien Común, logging concessions not only cover vast expanses of Peru’s Amazon region, loggers also extract timber illegally from Native lands and protected areas, and sometimes cross the border into Brazil. Several years ago, uncontacted Indians killed two loggers and injured one in Alto Purús National Park, which borders Brazil near the community shown in the BBC film.

Isolated tribes in Ecuador, to the north of Peru, face similar threats, and occasionally fight back. Ecuadorean ecologist Eduardo Pichilingue, who ran the Environment Ministry’s program for isolated tribes until he was fired for criticizing a government decision to allow oil drilling in a concession where uncontacted groups live, said that some of them have killed loggers. He says the spear-riddled body of logger Luis Mariano Castellano Espinosa was discovered in the forest in March of 2008. Pichilingue explained that when uncontacted groups kill an intruder, they may leave as many as 30 or 40 spears in the body as a message to other outsiders who might consider invading their territory. He added that loggers and settlers all carry guns in the forest and don’t hesitate to shoot at the Natives, though they rarely admit it. “When somebody from the outside dies, the media cover it, and we know their name,” he said. “When an isolated Indian dies, there is nobody to protest or go to the media. The jungle swallows those dead. We know that many Indians have died, probably many more than loggers or settlers, but it’s difficult to prove.”

Pichilingue said that in addition to threats from settlers and loggers, there is growing pressure to exploit oil reserves beneath the lands of Ecuador’s last isolated tribes: the Taromenane and the Tagaeri. Though the government is trying to secure international funds to compensate for not exploiting oil reserves beneath Yasuní National Park—one of the most biologically diverse places on Earth and the home of several uncontacted groups—it has announced plans to auction new oil concessions in the same region.

Uncontacted Natives have also been detected in Peru near the border with Ecuador, in an area where the Anglo-French company Perenco is currently exploring for oil, with plans to drill and build a pipeline. Soria explained that the Instituto del Bien Común and other groups asked the government to create a reserve in that area years ago, but the state has ignored that and five other proposals for the creation of reserves for tribes in voluntary isolation. “The Peruvian government doesn’t want to title indigenous lands,” said Soria, who noted that Peruvian President Alan García has questioned the existence of isolated Natives in the past. Soria complained that the government agency responsible for protecting the five reserves that Peru has created for tribes in voluntary isolation, INDEPA, doesn’t do its job.

Soria cited the case of the Murunahua Reserve, which also borders Brazil, near the community that the BBC filmed. He said loggers extract timber from the reserve legally, from concessions that predate its creation, but also from areas where logging is illegal. Following the release of the BBC footage, the García administration agreed to work with Brazilian authorities to combat illegal logging along the border, which FUNAI and some NGOs had been requesting for years. Survival International recently distributed a 2006 U.S. embassy cable released by WikiLeaks in which the then-U.S. Ambassador to Peru estimated that 70 to 90 percent of its mahogany exports were illegal.

Jorge Payaba, a Shipibo Indian who runs the program for isolated peoples at the Native federation FENAMAD, in Peru’s Madre de Dios department, said that illegal logging was rampant in the Madre de Dios Territorial Reserve for Indigenous Peoples in Voluntary Isolation following its creation in 2002. FENAMAD consequently took charge of a checkpoint on the Las Piedras River at the entrance to the reserve in 2006, and has since managed the post in cooperation with the Yine community of Monte Salvado. He said the station, which is equipped with a satellite phone and Internet access, has been effective in stopping loggers, though he fears that they may be entering the reserve via other rivers. “[The Indian affairs agency] and the Environment Ministry should keep loggers out of the reserve, but they don’t. We’re doing they’re job,” Payaba said.

According to Payaba, efforts to keep loggers out of the reserve seem to be working, since isolated groups have been moving downriver during the dry season, when they often steal crops from the farms at the edge of the reserve. He explained that he saw hundreds of uncontacted Natives on the opposite bank of the Las Piedras River from Monte Salvado in 2007, and his brother Ruben, who works as a forest guard at a checkpoint on the Tahuamanu River—the other main route of access to the reserve—recently had to flee downriver in his boat when a large group of warriors attacked the post, broke into a storeroom, and stole machetes, tools, bedding and other modern amenities. Payaba believes that uncontacted Natives often steal things from logging camps, since some of their spears and arrows that he has found are decorated with nylon rope, cotton, or synthetic fibers. He noted that they risk their lives by doing this, since they not only could get shot, but might also pick up a disease that could decimate their people. “They are our relatives. We can’t let people come in and contact them by force and spread diseases, because they don’t have the defenses,” he said.

Payaba cited the case of the Harakmbut, one of the principal tribes in southeast Peru, which had an estimated 10,000 people when missionaries first made contact with them in the 1950s. The tribe subsequently suffered various epidemics and there are currently 3,000 Harakmbut. “We want to avoid this happening to our brothers and sisters in voluntary isolation,” Payaba said.