top of page
  • .

Illegal gold mining in the Amazon could be killing millions of animals



As illegal gold mining ramps up in the Amazon, the toxic mercury used in the process is poisoning hundreds of animal species, with almost all of the 330 primates alone being tested proving positive for contamination.


Four scientists in the Peruvian jungle put a small-eared pygmy rice rat into a plastic chamber and piped in anesthetic gas until it fell asleep. They then removed the creature from the chamber, fitted it with a miniature anesthetic mask, and measured its body parts with a ruler before gently pulling hairs from its back with tweezers.


The hairs were bundled into a tiny plastic bag and taken to a nearby lab at the Los Amigos Biological Station for testing to determine whether the rat is another victim of mercury contamination.


Around 46,000 miners are searching for gold along riverbanks in the rainforest of Peru's Madre de Dios region in Los Amigos, the country's epicenter of small-scale mining.


Reuters accompanied the researchers in Madre de Dios over three days in late May and reviewed their previously unreported findings. Their data showed mercury contamination from informal gold mining making its way into the biodiversity hotspot's mammals — from rodents to ocelots to titi monkeys.


The amount of gold collected by unlicensed miners is far larger than elsewhere in Latin America, and it is ballooning so quickly that environmentalists fear that even a remote reserve like this one has little chance of survival.



Several studies have shown that humans and some birds can suffer neurological illnesses and immune diseases after consuming mercury-contaminated water or food.


In the Amazon, where more than 10,000 species of plants and animals are at risk of extinction because of forest destruction, scientists do not yet know its full effects on other forest animals.


Leaders from the eight countries around the Amazon will discuss how to end illegal gold mining in Brazil next week.


Colombia has proposed a regional pact to end illegal mining, although it has not suggested a deadline to reach that goal.


A research team from the San Diego Zoo Wildlife Alliance, the California nonprofit Field Projects International and Peruvian partner Conservación Amazônica have collected fur and feather samples from more than 2,600 animals representing at least 260 species, including emperor tamarins and brown capuchins, in the 4.5 square kilometer area around the Los Amigos station.


Capuchin monkeys are one of the 260 species of which feathers and fur have been tested from.

Biologist Mrinalini Erkenswick Watsa of the San Diego Zoo Wildlife Alliance said, "Of the 330 primate samples tested so far, virtually all showed mercury contamination -- and in some cases the levels were 'astounding.'"


The vast majority of small-scale or artisanal miners in the Amazon are mining illegally in protected areas or working informally - outside reserves but without explicit permission from the government. The Peruvian government estimates that illegal miners dump about 180 metric tons of mercury in Madre de Dios annually.


If mining is not stopped in the Amazon, it will continue to cause irreparable damage to nature and the environment, leading to deforestation, mercury contamination, and the sedimentation of vital rivers. Illegal mining has become one of the main drivers of deforestation in the Amazon, and it is a major criminal economy, underpinned by corruption, the use of violence, and the instrumentalization of local populations by NSAGs.


The spread of mining in the Amazon has had drastic social and environmental impacts, including invasions of indigenous lands by wildcat miners that have fueled deforestation and displacement of local communities. In 2019, deforestation caused by illegal miners in the Amazon rose 23 percent to a record 10,500 hectares.


The Brazilian government has initiated operations aimed at dismantling extensive illegal gold mining activities in the Amazon's Yanomami. Colombia has proposed a regional pact to end illegal mining, although it has not suggested a deadline to reach that goal.


(Callan Williamson)


bottom of page