About a year ago we adopted a Grey via this board & he was fully feathered on his head, back & wings, and pretty bald elsewhere. Like you, we didn't know if we were going to live with a half-bald bird for the rest of its life.
There is a homeopathic remedy that goes in their water called "Pluck No More" by King's cages (I think). It is pricey - about $30 for a bottle that should last a month. Either it will work or it won't, depending on your bird, and you'll know after 1 or 2 bottles (it takes a few weeks to start to work). I've told you all I know about it - we used 1 bottle on a greenwing macaw & he seems to have stopped plucking (although he still looks a little ratty).
Our plucked Grey had previously belonged to a smoker & had lost the love of his life, so was in mourning. We were told to give him preening toys so he preened them, not himself. Didn't work - he was terrified of most toys.
But we were also advised to give him a phone book [with the cover removed] to shred instead of his feathers. That didn't work the first time because he was afraid of the phone book, too. So we started small - with a paperback. He got into that, moved up to a half-sized phone book - and now will work industriously on the "big" phone books. And his chest is fully feathered, although I truly thought he'd be partways bald for his whole life.
In my opinion - the hard part is watching them pluck when they first arrive. YOU know you will be giving them a good life, but THEY don't know it & everything parrot takes patience.
The 'before' pictures don't completely capture the extent of Gilbert's nakedness, but he hadn't damaged his follicles & was refeathered inside of a year. I don't know if your Grey will refeather & frankly, bald or feathered, Gilbert's personality is HUGE. I'd take him either way.
So, if you take the Grey:
1. Do a well-bird check soon after the bird arrives to rule out medical causes.
2. Don't worry about the plucking - it will take the bird a while to settle into a new routine.
3. Try the "Pluck No More." It could help. We used it on the macaw specifically because he seemed to enjoy playing with & sucking on the feathers he'd removed. I wanted to break the cycle.
4. Try preening toys
5. Try the phone books
6. If the Grey is currently on a seed diet, decrease the peanuts & sunflower seeds & try for fruits, veggies, egg, etc.
Good luck!
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