When outsiders come into contact with isolated people living deep in Brazil or Peru's Amazon forest, disease inevitably breaks out. In some cases, bouts of viral or bacterial outbreaks have killed up to half a tribe's population. This isn't just a problem from the past, either. When men from an isolated tribe emerged from the jungle and made contact in a small mainstream village in Brazil recently, several of them almost immediately came down with the flu, which they could bring back with them to their home in the forest.
Disease is just one problem with these types of meetings. They can disrupt to an isolated population's way of life, or violence can break out. A team of researchers led by Robert Walker from the University of Missouri has developed a way that could circumvent these problems: satellite monitoring of remote tribes.
While the idea might sound a bit eerie and invasive, those experts think that it is preferable to the alternative. The new method, they describe in the journal Royal Society Open Science, is superior to traditional once because it is noninvasive, cheap and provides almost instantaneous real-time results.
To test the validity of this method, the researchers analyzed the locations of five villages located along the Envira River in Western Brazil, ranging in size from about 50 to 300 residents. They used data from past overflights—the traditional method of keeping an eye on a tribe, in which a plane noisily flies over the forest cover and may or may not find the village it's looking for—and compared those findings with the satellite method.
The satellites, they found, had high enough resolution to offer a peek into the number of homes and gardens present, which can be used as a proxy for population estimates. While planes are sometimes able to capture images that include people and objects like pots and machetes, that method's high cost in terms of both money and disruption to residents' lives does not seem to justify those oftentimes sensationalized photos.
Keeping an eye on villages from afar, the researchers think, could help the people living there in the long run. As the researchers write, "Most if not all of the other some 50–100 isolated indigenous peoples in Greater Amazonia face dire situations in terms of small populations struggling against an onslaught of external risks." If a village suddenly begins to move, or starts to disappear, it could be a sign that drug traffickers are in the area, that disease has broken out or that one of a myriad of other things has gone awry.
This type of surveillance could inform governments of areas that need to be protected and could clue in experts when problems arise. Experts could venture into the jungle to see what has gone wrong and whether they can help. Otherwise, they will stay away and allow indigenous people to get on with their lives free from harassment.