I have a maked love bird with other 3 love birds together. He plucked his 
chest clean of feathers. You could see the seeds in the crop. I sprayed him 
with water every single day, sometimes twice, he got his feathers back and I 
think that now he wants a protective feather coat. He hasn't plucked yet.
Give him a daily bath to see if it helps. Also, keep him occipied with toys
and if posible, change his cage to a better, bigger one. Ussually, plucking
is a psychological problem. If caught early, it might have a chance to be 
fixed before its too late.  
 
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