I have observed that the animals and birds have a kind of idea that humans' face (and eyes) is a primary front to observe the world around them. If one has his back toward the bird, then the bird won't feel that uncomfortable. But when you stare at an animal or bird, it becomes shy or afraid and assumes it is under observation and runs away, or gets ready to defend itself. e.g. Cobra snake stares in the eyes and tries to attack its victim in the face. That's just my observation which could be ridiculously wrong. Please guide me in the right direction. Thank you.