by Bluesbird Exotics on Sat May 17, 2008 2:45 pm
My first thought would be that she bloodied herself in a night fright. If you've never read about those, maybe someone here longer than I could link relevant threads for you. It involves the bird getting spooked in the dark and thrashing wildly about the cage. Most cockatiel parronts use night lights and close window blinds to help prevent spooking. Are you in Florida or south Texas? Large wood roaches can scare sleeping birds in those climates.
Cockatiels are, as a rule, very peaceable birds. I would be very surprised if your male did as much damage as you describe. Males often overpreen their mates in an effort to persuade them to mate and lay eggs. Some will peck at one place enough to break new blood feathers and cause bleeding, or peck a spot raw causing bleeding. Usually this is a sign of poor breeding and, if the birds are not deeply bonded, it is usually thought best to separate them and let the male live alone, as sad as that is IMO.
I think the way you have separated your female is definitely the best thing you could possibly do. I encouraged you earlier to rehome both birds. I think you would do both birds a great kindness to rehome one, preferably the female so you can ensure that the male is never housed with a female again. If he has overpreened her, he is probably the son of an overpreener and either inherited or learned this unfortunate behavior early. It would be most unwise to allow him to pass his behavior on to his own chicks.
I hope your female heals quickly and there is no recurrence.