Chickens are not the preferred food of eagles. American (Bald) eagles eat mostly fish and golden eagles eat mostly small mammals like rabbits and squirrels. I suppose if an eagle was very hungry and could find nothing better, he would indeed eat a chicken. read more
Even then, chickens are not their preferred prey. The raptor that most often preys on chickens is probably the Red Tailed Hawk, because it is relatively common for a raptor, and because it is large enough to prey on chickens easily. Bald and golden eagles and other larger birds may prey on your chickens, too. read more