Scientists turn to eDNA to protect Rwanda’s mountain Gorillas

Rwanda is using environmental DNA technology to help detect endangered species like mountain gorillas and golden monkeys, as scientists and conservationists seek new ways to monitor biodiversity in dense forests threatened by climate change and human activity.

Deep inside Rwanda’s Volcanoes National Park, scientists are testing a new method to track wildlife hidden beneath thick vegetation and rugged mountain terrain.

Known as environmental DNA, or eDNA, the technology identifies species through traces of genetic material — including fur, saliva or feces — left behind in soil and water.

The approach is being introduced by the African Wildlife Foundation in partnership with the Rwandan government and conservation groups, with the goal of building a comprehensive inventory of species across the country.

Researchers say the method could strengthen efforts to protect endangered animals such as mountain gorillas and golden monkeys while reducing direct human interference during wildlife surveys.

Conservationists seek faster and wider monitoring

Traditional biodiversity monitoring has long relied on ranger patrols, field observations and camera traps triggered by animal movement.

But in difficult terrain like the Virunga mountains, which stretch across Rwanda, Uganda and the Democratic Republic of Congo, monitoring wildlife remains a challenge.

“The key component of habitat conservation is ecological monitoring,” said Patrick Nsabimana, Rwanda country manager for the African Wildlife Foundation.

“So, we have selected eDNA as one of the new technologies to bring new solutions and complement existing methods.”

Scientists say eDNA can detect several species from a single sample collected in rivers, ponds or wetlands downstream from wildlife habitats.

“With one kit, you can assess multiple species, including amphibians, small or large mammals and birds,” said biodiversity researcher Deogratias Tuyisingize of the Dian Fossey Gorilla Fund.

The technology is already being used to monitor how species return to rehabilitated habitats and to identify invasive species before they spread.

Challenges remain despite promise

Conservationists believe the technology could also support anti-poaching patrols by helping authorities better understand where endangered species are present.

But experts caution that eDNA still has important limitations.

“eDNA is really helpful, but it only tells us the presence of something,” said James Munyawera, a laboratory specialist with the Dian Fossey Gorilla Fund.

“It does not tell us the abundance or the location.”

Researchers say the technology cannot accurately determine how many animals are in an area because DNA traces can travel long distances in water or remain in the environment long after an animal has moved away.

Another challenge is the lack of African genetic reference databases needed to accurately identify species from collected samples. Many existing DNA libraries are based in Europe and North America.

To address that gap, researchers in Rwanda are building regional databases while also training park rangers and local communities to help collect samples for future monitoring efforts.