Scientists Use Satellite Images to Track Uncontacted Amazonian Tribes

Apr 24, 2014 by

U.S. researchers from the University of Missouri and the University of New Mexico have used satellite images to track the movements and demographic health of an uncontacted tribe in the Brazilian state of Acre near the Peruvian border.

Members of an uncontacted tribe in the Brazilian state of Acre. Image credit: Government of Brazil.

Members of an uncontacted tribe in the Brazilian state of Acre. Image credit: Government of Brazil.

Remote surveillance is the only method to safely track uncontacted indigenous societies and may offer information that can improve their chances for long-term survival.

The scientists used Google Earth satellite imagery to estimate the area of the fields and the size of the village belonging to the tribe, as well as the living area of the tribe’s temporary housing, and compared that with similar estimates for 71 other Brazilian indigenous communities.

“We found that the estimated population of the village is no more than 40 people. A small, isolated village like this one faces an imminent threat of extinction,” said Dr Rob Walker, the first author of a paper appearing in the American Journal of Human Biology.

“However, forced contact from the outside world is ill-advised, so a non-invasive means of monitoring the tribe is recommended.”

“A remote surveillance program using satellite images taken periodically of this group would help track the movements and demographic health of the population without disrupting their lives,” Dr Walker said.

Using information captured from remote surveillance, scientists can help shape policies that mitigate the threats of extinction including deforestation, illegal mining and colonization in these remote areas.

“Additionally, surveillance also can help locate isolated villages, track patterns of migration over time, and inform and create boundaries or buffer zones that would allow tribes to stay isolated,” Dr Walker added.

Amazonia harbors as many as 100 locations of isolated indigenous peoples.

“Deforestation, cattle ranching, illegal mining, and outside colonization threaten their existence. Most of these tribes are swidden horticulturalists and so their slash-and-burn fields are observable in satellite images,” Dr Walker said.

“But, they do move around, sometimes in response to external threats, and this movement requires constant monitoring if there is to be any hope of preserving their habitat and culture.”


Robert S. Walker & Marcus J. Hamilton. Amazonian societies on the brink of extinction. American Journal of Human Biology, published online April 21, 2014; doi: 10.1002/ajhb.22552