Jennifer,
Hard to say, as she is the alpha, so unlikely that she's getting picked on, and if anything, I think she may be picking on others (which could indicate a space issue, which I understand can lead to stress/feather loss). We noticed that the lowest chicken in the pecking order, the Black Star, had it's comb torn, and some blood drawn, so I'm wondering if there is some fighting going on.
How would I determine if pinfeathers are coming in elsewhere? Let me know.
I want to say that lice/mites are not a factor as I clean the coop every two weeks and spray down the dry bedding with diatomaceous earth, however, I haven't been able to setup their dust bath in awhile, which I need to, so not sure if not getting a dust bath recently might have led to this, but again, they are getting diatomaceous earth in their bedding to reduce the threat of lice/mites.
Let me know if there's anything I'm missing, or additional steps that I can take to see if it might resolve this issue for her.
Thanks!
Tom