I turn off the electric fence every morning and let the chickens wander. At dusk, I shut the coop door and turn the fence back on. My yard is surrounded by crows every day. I've read that crows will alert chickens to hawks and other predators. There are bears, hawks, coyotes, and other predators in my area.

"They will surround predators and squawk at them, warning all the surrounding prey of the danger. The crows almost make a game of seeing who can get the closest. It is difficult for a fox to execute his cunning while surrounded by a murder of crows screaming bloody murder.
The chickens instantly recognize these alarm calls, and they respond quickly. They seek shelter quietly without the mindless panic caused by a predator appearing suddenly in their midst. The crows’ alarm calls can also serve to alert you of a potential menace."
https://birdwatchingpro.com/attractin...