Illegal gold mining along the banks of northwestern Colombia’s Atrato river is causing severe contamination and deforestation for the small, impoverished riverbank communities made up of predominantly Afro-Colombian and Indigenous peoples.

Sediment and pebbles are all that’s left on the earth around much of Bernardino Mosquera’s small riverside community in northwest Colombia’s Choco region.

Just a year ago, healthy shrubs and trees filled this important biodiversity spot teeming with species native to the land. But then illegal miners arrived, using their heavy machinery to dredge the riverbeds for gold.

“It’s just desert here,” said Mosquera. “Illegal mining affects the ecosystem in every way … it leads to degraded land. There are no trees. The water sources are drying up, it’s polluted by mercury.”

Mosquera is a river guardian, a title bestowed upon him and 13 others. The unpaid guardians serve as the eyes and ears of the Atrato River: They liaise with government institutions on environmental and social issues in the face of aggression from armed groups and hope to reverse the devastation they see along the river. But after eight years, they are increasingly disenchanted by the lack of support from institutions and growing threats from armed groups that control the region.