What changes the behavior answer
Watch the whole bird: posture, feathers, eyes, feet, breathing, voice, and whether the bird is trying to move away.
Look for distance signals
A bird that leans away, turns aside, steps back, raises wings, pins eyes, hisses, or freezes is asking for more space.
Change the environment
Reduce sudden movement, loud noise, direct staring, hands over the head, predator pets, and crowded cage access.
Build confidence slowly
Use routine, treats at a comfortable distance, target training, and predictable movement. Let the bird choose to approach.
Important distinction
Fear can look like aggression. A lunge or bite may be a scared bird trying to make space.