Bare Butt Brahma. Bullying? Not urgent.

[Lemon-Drop]

My buff Brahma girl, Cupcake, has a bare backend. I’m trying to figure out the cause(s)

Info:

She is a 1 year old Buff Brahma hen. I don’t know her exact weight-something like 8-9lbs.
Her rear end is red and the feathers are missing. This has been going on for the last month or so.
She is the only one affected by this. The other chickens all have fluffy butts.
She otherwise seems very healthy-clucking when I pick her up, running to the feeder, etc.
I’m trying to figure out what the cause is, and what I can do to help her. She eats Purina Flock Raiser pellets (20% protein), and the very occasional treats (mealworms, scratch, kitchen scraps, etc. but not often at all)
She lives with 14 other hens plus a rooster, bedding is pine shavings in the coop with sweet PDZ on the poop boards. I checked for mites, didn’t see any. Poop is normal. She also doesn’t have much of a tail since this all started.

I have a suspicion that it’s bullying, but haven’t visibly witnessed it yet. Suggestions? Tips? Causes? Thanks in advance!

 

[coach723]

Looks like feather picking. Bare butts are often from picking on the roosts. How big is your coop and run? Sometimes redoing your roosting arrangement can stop this.

 

[Lemon-Drop]

Looks like feather picking. Bare butts are often from picking on the roosts. How big is your coop and run? Sometimes redoing your roosting arrangement can stop this.

The coop is 6 by 8 (3ft/bird (I know the recommendation is 4ft each, but so far there hasn't been any problems)

The run is 750 sqft (I can't remember the length x width, though) so about 50ft/bird

 

[coach723]

Recommended space is just that, recommeded, your birds themselves will tell you if it's adequate or not. Some birds like/demand more space, some don't mind squeezing together. Any time there is any change in the flock, things can reset and change. I had a roost set up once that put them kind of butt to head on roosts and had a bunch of bare butts from feather picking. I changed my roosts so they were multi level and no butts to heads, and it stopped. Since she's a relatively large bird, she may be a bit in someone elses perceived space.

 

[coach723]

Go out when they are going to roost and do some observing. See if you have a bully that is targeting her, or if it's just a space issue. I have at times had dividers on my roosts in places, like temporary walls, to keep more aggressive or testy birds from picking on others. Gives them their own 'corner' so to speak.