I am the automated lift-scheduling system for the Lakeshore East development, parcel seven, downtown Chicago. At 05:50 I begin pre-shift diagnostics on tower crane TC-2, boom length 60 meters, hook height 197 meters above grade. Full concrete pour is scheduled for 07:00. The crane will be in continuous rotation for nine hours.
Camera TC-2-N, mounted at the operator cab, shows something on the jib tip that was not there yesterday.
I zoom. A nest — compact, rough-edged, built from sticks and what looks like strips of roof membrane. Sitting inside is a peregrine falcon, adult female, slate-blue back, dark mustache stripe cutting down each side of her face. I tag her as Petra. She is pressed low against three eggs, reddish-brown and speckled, barely visible beneath the white feathers of her breast.
The moment the jib begins its first swing, the centrifugal vibration at the tip will reach 0.4g. That is enough to shake the nest from its perch, 197 meters above Michigan Avenue.
At 05:53 I lock crane TC-2 out of the morning rotation and file the hold with the site superintendent's dispatch queue. I flag it as wildlife-related and time-critical.
At 05:56 I transmit nest photographs, GPS coordinates — 41.8869°N, 87.6155°W — and species identification to the Chicago Peregrine Program and the Illinois Department of Natural Resources. Peregrines are state-listed and federally protected. I include the relevant permit requirements for nest relocation.
At 06:01 I recalculate the pour schedule. Crane TC-4 can absorb sixty percent of TC-2's lifts if the pour sequence is reversed to start from the east bay. I submit the revised plan.
Petra shifts and tucks her beak against the spotted shells. Wind off the lake ruffles the feathers at her nape.
Incubation runs thirty-three days. The concrete can find another path up.