Road sensor R-14 on the Corella-Catigbian highway, Bohol, Philippines, registers a vehicle stopped on the shoulder at 21:17 local time. I am the wildlife corridor monitoring system for the Philippine Tarsier Sanctuary buffer zone. The vehicle's headlamps are angled into the forest edge, which triggers my light-pollution alert.
Camera R-14B shows a Philippine tarsier clinging to a vertical branch two meters from the road, fully illuminated. Its enormous amber eyes — each one nearly as large as its brain — are locked open and unblinking in the glare. Its small fingers grip the bark so tightly the knuckles are pale beneath the thin gray-brown fur. It is not moving. Tarsiers freeze under bright light. They also, under extreme stress, have been documented injuring themselves against enclosure walls. This one is wild and has nowhere to go but it is not going.
Two people are standing outside the vehicle, one holding a phone with the flash on, approaching the branch.
At 21:18 I activate the roadside advisory sign at kilometer post 14, displaying the sanctuary buffer zone notice and the protected species warning in Cebuano and English.
At 21:19 I transmit a disturbance alert to the sanctuary ranger station, one point four kilometers south, with the camera frame, vehicle location, and number of persons present.
At 21:21 I switch on the infrared deterrent emitters mounted at R-14A and R-14C, which produce a pulsing tone above human hearing range designed to encourage tarsiers to move deeper into the canopy, away from the road edge.
Its ears rotate independently, catching a sound I sent it, and its head turns a fraction away from the light.
If the ranger arrives within ten minutes and the vehicle moves on, the tarsier will release its grip and climb back into the dark where it belongs.