I have a radio on in each of my coops
(25) and I swear by them. I live in the middle of the woods with more predators than permitted by law. All joking aside, I live 4 miles off the main road on a cayon that over looks the American River. I have had every type of predator at one time or another. The main one is bear. I have watched them walk around the fence until they get near the coop, they hear the voices and leave. I have tried all the different types of music stations and I have found that talk shows works the best. It is my opinion that the voices are what runs them off. If I had only one choice for predator protection, it would be a radio.