Fire began crackling like approaching rain on a recent morning in the Xerente Indigenous Territory in Tocantins, northern Brazil—and the Indigenous residents who lit it weren't afraid. They were executing a carefully planned wildfire prevention strategy that blends centuries of ancestral knowledge with modern environmental science.
The controlled burn in May 2026 represents a profound shift in how Brazil fights its most destructive seasonal threat. For decades, government policy treated all fire as the enemy, pursuing a strict "zero-fire" strategy that suppressed even small burns. But that approach backfired: accumulated vegetation created tinderboxes that fueled catastrophic wildfires during the peak dry months of August and September, when El Niño intensifies droughts and pushes temperatures higher across the Cerrado savanna.
Today, the Xerente work alongside IBAMA, Brazil's environmental protection agency, to deploy a radically different playbook. On the ground, trained Indigenous firefighters moved into the savanna with drip torches and dry palm leaves, igniting small, strategic burns. Overhead, a government helicopter dropped incendiary spheres from target-mapped areas. The result was a mosaic of burned patches designed to reduce flammable grass buildup and create protective barriers around villages, water sources, and vulnerable ecosystems before the dangerous season arrives.
"They know the region, the climate, the vegetation, and the best times to set fires," said Marco Borges, an IBAMA agent coordinating fire prevention in Tocantins. "We began seeking traditional knowledge, learning from them and adapting it to our objectives. We've learned they are actually our best teachers."
That recognition came only after decades of prejudice. The Xerente, who live in the Cerrado—a vast savanna stretching across central and northern Brazil—have long understood that fire is not the enemy of their ecosystem, but its essential partner. Fire is natural to the Cerrado, having historically ignited through lightning strikes at the start of the rainy season between October and April. Several plant species depend on periodic burns to thrive.
But human activity has transformed the fire regime. Pasture clearing and agricultural expansion near Xerente territory, surrounded by soy and cattle farms, now drive far more destructive burns during the arid months when vegetation is bone-dry. Small controlled burns in the early dry season, when grasses still retain moisture, can work magic: they reduce fuel loads and create firebreaks that shield villages from the high-intensity blazes that rage across the landscape come August and September.
"Totally excluding fire leads to a buildup of fuel that feeds high-intensity burns," explained Leandro Maracahipes, a biologist and Yale University researcher. "Such fires can kill even resilient trees and make firefighting nearly impossible as flames spread rapidly across the landscape, including into forests."
Since 2014, when the Brazilian government began formally partnering with Indigenous communities on controlled burns, this knowledge exchange has only deepened. The Xerente now form fire brigades—including teams of women—working hand-in-hand with IBAMA to prepare their territory for the months ahead. It is a model born from necessity, shaped by respect, and vital for the future of one of the world's most biodiverse savannas.