Mongabay journalist Karla Mendes has received the 2025 John B. Oakes Award from Columbia University’s Graduate School of Journalism.
Mendes was presented with the prestigious prize at an event in New York on Sept. 18 for her investigation documenting a direct connection between increased violence against Indigenous Arariboia leaders and the expansion of illegal cattle ranching in Brazil’s northern Maranhão state.
“Today, receiving this award is really an honor. Not for me, but especially to honor the memory of Paulo Paulino Guajajara, all the guardians of the forest, and all the Indigenous people who give their lives to protect their territory,” Mendes said at the award ceremony.
Paulo Paulino Guajajara was an Arariboia forest guardian who was killed by loggers in an ambush in 2019.

This is the first time Mongabay has won the Oakes Award for Distinguished Environmental Journalism, one of the top prizes recognizing exceptional contributions to the public’s understanding of environmental issues. It’s also the first time a Brazilian journalist has received the award.
The annual award, founded in 1993, recognizes journalists “whose work meets the highest standards of journalistic excellence” and “makes an exceptional contribution to the public’s understanding of environmental issues.”

“Congratulations to Rio-based Mongabay reporter Karla Mendes. She has done groundbreaking reporting on illegal cattle ranching on Indigenous land in the Amazon rainforest,” Jelani Cobb, dean of the Columbia Graduate School of Journalism, announced at the ceremony.
“Her investigation made a direct connection between the expansion of the cattle industry and an increase in crimes against people and nature,” Cobb added. “She risked her life multiple times to report on the ground, moving through areas controlled by the cattle ranchers.”

The award’s top prize is $5,000, with two other finalists receiving $1,500 each. Sharon Lerner of ProPublica and The New Yorker was recognized for her reporting on 3M executives suppressing evidence from their own scientists about the dangers and widespread contamination of “forever chemicals” from their products.
The other finalist was a team from Grist, El Centro de Periodismo Investigativo, Atlanta News First and El Paso Matters, who exposed that medical supply warehouses across the U.S. are leaking ethylene oxide, a toxic gas that can cause cancer, into nearby neighborhoods.
Read Karla Mendes’s investigative series “Dying for Arariboia” here.
Banner image: Mongabay journalist Karla Mendes receives the 2025 John B. Oakes award on Sept. 18. Image courtesy of the John B. Oakes Awards.