PITTBURGH — The National Aviary says the peregrine falcons living high up on the side of the Cathedral of Learning have welcomed their first egg of the season.

Carla laid the egg on Sunday afternoon. She will likely lay at least three more.

Aviary officials say Carla could lay one egg every 48 hours or so until the clutch is complete. Once the last egg is laid, she will start to incubate the clutch. In the meantime, the eggs can be safely left uncovered.

Carla, along with partner Ecco, will both incubate the eggs until they hatch in a little over a month.

Click here to watch the National Aviary’s FalconCam.