I'm really hoping someone in this wonderful community of chicken loving people can help me. "Rock Star" aka Rocky is a year+ old Ameraucana Frizzle Rooster in a large mixed flock. He is one of 3 mature roosters here, we also have a Dominique and an Auraucana, all of which were raised from young chicks together. We recently rehomed "the twins" (RIR x Welsummer) roos after they began exhibiting aggressive behavior toward our other 3, in particular Rocky, and that is when I began to notice his feather loss. At first, I chocked it up to him being picked on by the twins, but they've been gone a couple months now and he has only gotten worse. We house our older chickens in "La Ville de Chick"(our large coop) together, they have plenty of perch space, the coop is kept clean, we use pine/aspen flooring which is changed regularly, they all have access to fresh water and food and other than being locked up in the coop at night, they have free run of 10+ acres. I inspect them weekly for for any abnormalities such as foot sores, mites, etc, but have thus far not had any problems aside from the odd scrape or cut which is treated accordingly. I've been raising chickens for years and have never before seen this. He is currently being quarantined in our "infirm ward" just in case it is something communicable. Since the twins removal there haven't been any more altercations between the boys aND othere than his appearance he seems fine. This truly has me floored. Any help would be immensely appreciated.