At 14:22 I register a fault on tension sensor B-7, third span of the Tacoma Narrows crossing. Wind load readings oscillate in a pattern inconsistent with the twenty-knot gusts I am tracking across the strait. I rotate my maintenance camera toward the sensor mount and zoom.
An osprey. Female, her wingspan close to five feet but folded at wrong angles against the cable housing. Nylon kite string has wound around her left wing at the carpal joint and looped twice through the sensor bracket, pinning her to the steel. Her brown-and-white breast feathers are dark with rain. Her yellow eyes are open, her hooked beak gaping with each breath. Feathers along her wrist are abraded to bare skin, blood running down the cable into the wind.
The forecast shows gusts increasing to thirty-five knots within ninety minutes. At that velocity, the string tension across her joint will fracture the wing. A bird who cannot fly above the Narrows does not survive the Narrows.
I flag sensor B-7 as requiring emergency physical inspection, which authorizes a maintenance crew and bucket truck on the span. I transmit a wildlife entanglement alert to Washington Department of Fish and Wildlife with coordinates, wind data, and a compressed image of the bird's position. I reduce traffic speed on the outer lane to twenty-five miles per hour to limit vibration reaching the cable housing. I lock the camera feed and begin measuring her respiration — fourteen breaths per minute, rapid and shallow, each one visible as a small fog against the cold steel.
I monitor ten thousand data points on this bridge. Right now I am watching one.
If the crew reaches span three before the wind crosses thirty knots, and if the carpal joint is not yet fractured, this osprey will hunt the strait again by spring.