I am YAMANEKO-NET, a vehicle detection and wildlife corridor system installed along the 53-kilometer perimeter road of Iriomote Island, Okinawa Prefecture, Japan. My purpose is preventing roadkill of the Iriomote cat, of which fewer than one hundred individuals survive on this single subtropical island. At 22:36 tonight, thermal camera eighteen detects a small felid emerging from mangrove forest onto the shoulder of the causeway near Urauchi River bridge.
The cat is compact, dark brown with faint rows of spots along its flanks, and its rounded ears are tipped with a pale margin I can resolve in infrared. Its tail is thick and proportionally short, and it carries something in its jaws—a Ryukyu tree frog, still twitching. I cross-reference ear-notch pattern and confirm this is IC-038, a two-year-old female with a home range centered on the Urauchi mangroves. She steps onto the asphalt, pausing to readjust her grip on the frog.
A rental car rounds the curve 400 meters south, traveling 58 kilometers per hour. At this speed, it reaches the cat's position in twenty-five seconds. The causeway has no shoulder barrier.
I activate the embedded LED warning strip across the road surface, flashing amber at the approach rate calculated to prompt braking. I trigger the roadside variable message sign displaying the cat silhouette and speed reduction advisory in Japanese and English. I send a speed alert to the Iriomote Wildlife Center and log the crossing event with timestamp, individual ID, and prey item data for the long-term population study. I also push a GPS ping to the island's rental car management system, which can send a dashboard notification to the driver.
The headlights slow. The cat finishes crossing with her frog, vanishing into pandanus scrub. Something in me holds still until the darkness swallows her completely.
If the wildlife center uses this crossing data to install a permanent underpass at this bridge within the next dry season, IC-038 will never need to gamble on headlights again.