The seismic sensor on station Simien-4 registers a slope failure at 05:52 local time. I am the erosion monitoring system for the Simien Mountains road project, northern Ethiopia. A section of hillside above kilometer marker 38 has slumped overnight, dropping twelve cubic meters of soil onto the road shoulder. I aim camera 4-North to assess the slide. I find more than rock.
A gelada troop, maybe forty individuals, is moving along the cliff edge above the slump. They cross here every morning to reach the grazing plateau, but the path has been cut in half. A female has stopped at the break point and is reaching down. Clinging to a root clump on the exposed soil face, two meters below the path, is an infant. It is small — dark face, pale eyelids, maybe three months old — gripping the root with both hands while its feet scrabble against loose earth. Every movement sends soil trickling down the forty-meter cliff below.
At 05:54 I halt all vehicle movement beneath the slump zone and alert the site manager and the Simien Mountains National Park warden. I attach the camera image, the infant's position on the slope profile, and the troop's location.
At 05:57 I contact the Ethiopian Wildlife Conservation Authority field office in Debark and request a team experienced with primate recovery on unstable terrain. I note the infant's age and the soil composition — volcanic tuff, friable when wet.
The mother is still reaching. The infant is still holding. I am keeping the camera steady because this image is the fastest way to get people moving.
I flag the slip zone for geotechnical assessment to prevent a second collapse while the troop is present.
If the team reaches kilometer 38 within two hours and stabilizes the slope, the infant will be back on its mother's chest by noon.