http://www.baldeagleinfo.com/eagle/eagle3.html
" A bald eagle's
lifting power is about 4 pounds. They do not generally feed on chickens or other domestic livestock, but they will make use of available food sources. Bald eagles will take advantage of carrion (dead and decaying flesh), giving it a scavenger image, which causes some people to dislike eagles. Other people do not care for powerful and aggressive birds; while some object merely on the grounds that it is a bird of prey which kills other animals for food."
I'm still betting on coyote or raccoon. A few years ago, we were on vacation, my mom was taking care of the chickens, letting them out in the morning to free range, and shutting the coop at night. One day she was over in the afternoon for something, and when she came back a few hours later, several of my hens and my rooster were gone. The only thing left was one of my rooster's tail feathers. We had a corn field right next to the outbuildings. That fall, when DH was harvesting, he chased 3 coyotes out of the field. Several years before that, when we had corn in that same spot, all my barn cats disappeared in a matter of a few weeks. Again, coyotes in the field when harvesting.
And raccoons - had a mama raccoon go into my coop right in the middle of the day and kill my favorite broody. Fortunately, the dog alerted DH, and he got the coon before she could kill the chicks. The mother raccoon and her babies were no longer a threat to my flock after DH found them...