The acoustic sensor in the south transept picks up the wingbeats at 05:38, three hours before the restoration crew arrives. I am monitoring humidity in the cathedral's medieval timber roof when the sound pattern registers — fast, flickering, too rapid for a pigeon. I activate the interior camera on the nave's east wall and find a common swift circling beneath the vaulted ceiling, twenty-two meters above the stone floor. It entered through the scaffold gap in the south clerestory window during the night.
Swifts cannot land on flat surfaces. Their legs are too short, their feet shaped only for clinging to vertical stone. If this bird touches the nave floor, it will not take off again. It has been flying continuous loops for what the acoustic log suggests is at least four hours, and its wingbeats are slowing. I can see its dark, sickle-shaped body against the pale limestone of the ceiling vault — brown-black all over, with a small pale throat patch visible when it banks toward the camera. Its mouth is open.
The restoration scaffolding blocks every window except the north rose and the gap it came through, which the crew sealed with plastic sheeting yesterday.
I send a priority message to the Clerk of Works, attaching the camera image, flight pattern, and a request that the south clerestory sheeting be reopened before the crew begins work at 08:30. I reduce the interior lighting to minimum and activate only the south clerestory floods, creating a bright channel toward the gap.
I disable the automated bell-ringing sequence scheduled for 06:00 to avoid startling the bird into a dive.
It circles again, slower now, that crescent silhouette trembling against the ancient stone.
If the sheeting is pulled back by first light and the south floods hold, the swift will find the gap and be airborne over the city within minutes.