Sun Conure Hostility

Question
Hi, my Sun Conure is about 5 years old.  She (we assume the conure is a female) has for some reason become very hostile towards visitors and anyone who is not a member of the family living in the house.  I know she was not like this when we first got her.  She was fine for the first year, then she began attacking anyone who came into the house that was unfamiliar to her.  On some occasions, people she would adapt to and love to play with would take long leaves of absence (4  months), and return to only be bitten and attacked by Suki (her name).  We have tried to socialize her well outside the house, however she refuses to go to anyone and will just be constantly nervous.  We take her outside occasional, and she loves it outside.  She does not like children especially.  She will ruffle her feathers, puff up, and begin walking back and forth in her cage and become very aggressive or "show her wrath" on her toys.  

We do not know what is causing this hostility to the public, and it is quite embarrassing when we have visitors or anyone else over.  We have tried "time out" though it does not seem to be working very well.  We've also tried the "NO BITE" and ignore method, but she will just scream and scream, attack her toys until the "outsider" is gone.  

I noticed when we take her outside or into other buildings she is not as aggressive, but that could be due to the fact that she is so incredibly nervous of her surroundings, she doesn't know how to react.  However if anyone but family trying touching her, they will be met with a swift jab to the finger, or ear.
Sometimes she will go to another person as if accepting them, however after a few minutes or randomly she will just go for the ear and bite.

Do you know what is causing this or how we can fix it?  We have no intention of getting rid of Suki as we have accepted her as family, and we know she loves us.  She just needs a bit of control.  Please help :)
If there is any more information you need, I will respond with it asap.

Answer
Hi, Sagar.  Thanks for posting!

Your bird is behaving normally for a bird that has bonded to it's human family.  Yes, this bird could have been socialized better when it was a baby and growing up, but your conure is acting normally as far as "protecting" it's human flock from those it perceives as potential threats (whether you see them this way or not, your bird does).  You might be able to change this behavior by gradually introducing other people to this bird in a structured manner.  In other words, you'd have to slowly and carefully introduce select persons to this bird gradually over a period of time versus just allowing your bird to come out of it's cage and place the bird on someone's hand, shoulder, etc. (or however your friends/family approach the bird when they visit).  This is likely why visitors gets a bite to the ear.  Strangers to your home will most definitely not be welcome!  This process of retraining can take much time and patience over a period of time.

Taking a parrot outside definitely puts the bird in a different frame of mind!  When outside, the bird becomes more vulnerable to natural threats, such as predators and other dangers, so it's normal for your bird to become stressed and flighty when taken outside.  Also, I hope your birds wing flight feathers are clipped so the bird doesn't get away from you permanently.  If your bird gets away from you, you most likely won't be able to get him back.

Come back with any additional questions or if you need clarification on what to do.

Chrys