Barred Owls are busy in the fall. They start or renew pair bonds and reclaim nesting sites. Young adults build new nesting sites.
All this activity is hard to miss because there is a lot of communication between pairs and between young interlopers. It is the hooting season.
This is all in preparation for an early winter breeding season. Owls risk starting breeding in the worst weather months. Owlets stay near parents for a long time compared to most other birds. They stick close to parents through summer and, guess what, into early fall.
It takes this much time for juveniles to learn the skills necessary to hunt on their own. They need these skills before the rigors of their first winter as an adult.
And besides, their parents are off doing other adult things.