One of my drakes, Azula, has had some suuuper chewed up wing feathers all year, and I have no idea why. No one else in the flock looks like this, and he seems totally healthy otherwise, but his poor wings are a total mess! I kind of thought it might be our other drake pecking at him, but I haven't really seen that happening... anyone know what's causing this, and how I can fix it? He used to be so handsome