Like Something Out of “The Birds” Here a Couple of Mornings Ago

About 25 frenetic crows circling the neighbor’s tall spruce in the backyard. I started clapping as usual to create a change. What were they harassing and attacking repeatedly? I was stunned when an owl flew out the tree chased by the entire flock toward the western sky.
The crows probably have some nests there the owl tried to access to get at the babies. the ganging-up was quite startling and impressive. Crows are pretty bright as Candace Savage pointed out and have to have reasons for what they do. Anyway, yeah, it was disturbing like Hitchcock’s classic.