What are the common reasons for feather loss in a flock? My birds are just finished moulting in the last month and I have a couple with bare spots and some that are starting to look thin or bare in spots. I've looked closely and see no mites. They are not pulling each other's feathers out. The loss is not in places you would expect to see it from an over-zealous roo and my only roo has been at the county fair for the past 2 weeks anyway (coming home tonight). The first one to go bare was around her bottom and I suspected something to do with her cloaka but see no problem. The second has a bare spot on the front of her neck. Today I noticed that one is getting bare on the top of her head. When my son checked the birds in at the fair, the lady looking them over said that she saw signs that one of them had maybe had mites some time back because she had a couple broken feathers but she said she saw no sign of any problems on any of the birds now. The ones with bare spots in my flock have been totally bare (like I have already de-feathered them - totally bare to the skin) for a few weeks now. I just can't figure out the problem. Other than the feather loss, they all seem quite healthy. Egg production is on the rise since the moult is over and the weather is starting to warm a bit here. Ideas?