By Stephen Eisenhammer
SAO PAULO (Reuters) - Fire is not natural in the Amazon. Virgin rainforest, no matter how fierce the sun, is too wet to catch alight. If the forest burns it is almost always because of humans.
In August, around the peak of the so-called "queimadas" as the burning season here is known, the number of fires in Brazil's Amazon jumped to its highest since 2010.
Fire is the second stage in clearing the forest, usually for raising cattle. First, choice woods are cut and sold, then the rest is burned. It is cheap, it is effective, and it is hard to catch those responsible.
Cutting down the forest is illegal without permission, and using fire is against the law except in exceptional circumstances.
Yet fire is changing the landscape.
The latest data from August 2018 through July 2019 showed more rainforest was cleared than at any point in the past 11 years. An area larger than Puerto Rico was cut down. Preliminary figures suggest the rate has increased since.
Three teams of Reuters journalists spent weeks traveling thousands of miles across the world's largest tropical rainforest this year, witnessing the devastation of what scientists regard as a vital protection against climate change.
On the Trans-Amazonian highway, near the river port of Humaita, the August night sky did not go dark. The flames from a forest fire, stretching into the distance beside the road, glowed a dusky yellow. For days it burned.
Some people have taken protecting the forest into their own hands. Reuters spent seven days with an indigenous vigilante group fighting to keep illegal loggers off their land in the state of Maranhao.
One night in September, alerted by the rumble of heavy trucks, six Guajajara tribesmen – faces painted for battle – rushed to ambush a group of loggers.
At a choke point in the local network of rutted dirt roads, they lay in wait, a 4x4 blocking the road, rifles and handguns at the ready.
When the trucks arrived, the loggers, who numbered around eight, were first to fire. The Guajajara shot back, forcing the loggers to scatter into the forest. The indigenous warriors burnt the trucks, piled high with freshly cut lumber.
One of the men that night was Paulo Paulino Guajajara. He knew it was dangerous work and spoke frankly of his fear. "I'm scared at times, but we have to lift up our heads and act. We are here fighting," he said.
Four weeks later, he was dead. Members of his tribe said loggers had shot him through the head.
(Reporting by Stephen Eisenhammer, additional reporting by Jake Spring, Ueslei Marcelino and Leo Benassatto; Editing by Mike Collett-White)