Agro-industrial development is putting intense pressure on the Chaco woodlands of Bolivia, Argentina, and especially, Paraguay.

The worst repercussions of this deforestation – besides its critical role in tropical deforestation’s release of 1.5 billion tons of carbon each year – falls on the uncontacted indigenous Ayoreo tribe.

Paraguay’s uncontacted Ayoreo Natives depend on the forest for their survival, which the indigenous Ayoreo has protected for thousands of years.

But they’ve been continually forced to run from the cattle ranchers’ bulldozers, who have taken over much of their land.

Paraguay’s Environment Ministry violated national and international law by quietly issuing an environmental license to cattle ranchers to bulldoze a UNESCO Biosphere Reserve, the last refuge of uncontacted Ayoreo. It has put their lives in extreme danger, the Indigenous advocacy organization Survival International reported last December.

The trouble has been brewing for decades. Paraguay’s Chaco Biosphere Reserve documented it in 2005. “In the last two decades old processes have intensified, partially affecting the Paraguayan Chaco Boreal … It has led to a growing impoverishment of the entire system, with a significant impact on the social and cultural field, especially affecting the already destabilized groups and indigenous communities.”

Now, according to a new scientific study by the University of Maryland, the development of cattle ranches in Paraguay’s Chaco woodlands within the western half of the country has resulted in the highest rate of deforestation in the world.

Bulldozers are constantly at work, clearing their forest, their homes and gardens, and the uncontacted Ayoreo are forced to run away. Any contact with the ranchers could kill them as they lack immunity to diseases brought in by outsiders.

Ayoreo forcibly contacted since 1969 by colonists, bulldozer operators, ranchers, and driven from their forest homes by manhunts developed respiratory diseases after contact such as tuberculosis. Many have died, reports Survival.

In the last manhunt 25 years ago, they captured over two dozen of the tribe’s members, and killed five, reports Survival. The US-based fundamentalist missionary organization the New Tribes Mission was involved in the manhunt, and faced a storm of criticism. Listen to the moment the uncontacted Indians were attacked (mp3 audio file).

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