Falcon

Hi, everybody. I'm a new comer. I has recently bought a new female budgie. It's now around 6 months old. She isn't afraid of my fingers now. She can stand on my fingers. But she doesn't want me to touch her. Unless she is satisfied after eating, she bites me when I try to touch her. What does she behave like this? P.S. Just a piece of extra information... I originally has a male budgie. He is now around 4 years old.