My neighbor across the street had chickens, and they were completely free-range, roosting in the trees at night. We have tons of coons around here too! She never lost any chickens until she started putting the hens in a coop (tired of the constant egg-hunt) and the coons broke in. Another poster said that must have been sheer luck, as they lost chickens that way, but she had a good idea--wrap the trunks of the trees they roost in with aluminum or some other slippery surface that the coons can't get a grip on. It might be worth a try if you can't get them into a safe coop.