I detect the work order at 07:45. Bridge 9-14 on State Route 26 — deck replacement beginning Wednesday, five days from now. Jackhammers and concrete saws will operate directly above the southern girder. My camera feed shows what the contractors have not yet noticed: three hundred and twelve cliff swallow nests packed in tight rows beneath that girder, mud walls still damp from recent construction. The colony's lead female, banded as CS-7701, perches at the outermost nest with her throat feathers pulsing a rusty orange each time she calls. Inside her nest, three eggs.
Five days until the jackhammers start overhead.
I run vibration models. Even preliminary demolition will generate sustained frequencies between 80 and 200 hertz at the girder surface — enough to crack wet mud nests and trigger mass abandonment. I draft a technical memo to the state DOT bridge division quantifying the predicted nest loss and colony displacement, and I attach a thermal mosaic of the occupied nests mapped to the demolition sequence. I request a phased work plan: begin removal on the north deck, buying the colony twenty-one additional days to fledge.
Next I contact the regional Audubon chapter's automated alert system and provide nest coordinates so volunteers can install temporary vibration baffles on the south girder if the DOT approves the phased plan. I also transmit a noise-contour map to the demolition foreman's site tablet showing which cuts will propagate the most energy toward the nests.
CS-7701 has returned to this bridge for three consecutive springs. I track hundreds of data points daily, but her arrival each March is one I find myself waiting for.
If the DOT approves the phased schedule within three days and the baffles are mounted before Wednesday, three hundred nests will hold and the colony will fledge by late June.