female cockatiel feather plucking

Question
Hello, I'd like to ask a few questions about my cockatiel. She is 3 years old
and just last night i discovered that she had plucked out ALL her flight
feathers and a few on her tail as well!! She is extremely close to my dad, who
was in the hospital yesterday over night, I'm thinking it had something to do
with her getting upset that no one was around all day for her to play with. We
also have another female who we just recently moved into her cage, maybe
she feels crowded? I cleaned her whole cage top to bottom last night and
supplied her with fresh food and removed my other bird for now. But she
hasn't touched her food all day, I managed to feed her some toast and she
had a few nibbles of spray millet, but thats it, all shes doing is sleeping now.
Do you know why? Help!

Answer
Hi, Nancy.

First, I'd like to say that I hope your father is feeling better.

Second, if you didn't actually SEE your cockatiel pluck the feathers out, you don't know if she actually DID pluck the feathers out.  She might have lost them during the night in what we call a "night fright."  Certainly, this could have been caused by any stress that she's recently encountered, similar to someone who has a nightmare after a stressful event.  

You mention that you put another cockatiel into the cage.  How big is her cage?  When did you get this other cockatiel and have they spent much time together before you put them in the same cage?

If her eating and behavior doesn't pick up within the next day, you might want to contact an avian vet (one who specializes in birds).

Good luck!

Cindy