The flight zone of an animal is the area surrounding an animal that if encroached upon by a potential predator or threat, including humans, will cause alarm and escape behavior. The flight zone is determined by the animal's flight distance, sometimes called flight initiation distance (FID) which extends horizontally from the animal and sometimes vertically. It may also be termed escape distance, alert distance, flush distance, and escape flight distance.

Escape response, escape reaction, or escape behavior is a mechanism by which animals avoid potential predation. It consists of a rapid sequence of movements, or lack of movement, that position the animal in such a way that allows it to hide, freeze, or flee from the supposed predator. Often, an animal's escape response is representative of an instinctual defensive mechanism, though there is evidence that these escape responses may be learned or influenced by experience.