Throughout the day, the male owl (Pappa) calls to Pot Plant Owl sitting on the nest, to let her know he is watching the nest, I suspect.
When he appears at night, he spends a long time calling on the rooftop before going off to hunt for her. It's incredible to think that he is responsible for not only his food, but hers as well now.
We tend to only think of 'Poor Pot Plant Owl' having to sit there all day, every day, but give little thought to Pappa. Pappa is out there re-establishing his territory with his calling, watching the nest during the day, and hunting for both of them. He's also flying father now to get food, because once the hungry chicks arrive, they will look at the food sources closer to the nest.
He's doing a great job.