A kinematic analysis of optimal avoidance and evasion techniques for prey is presented. The analysis is mainly directed towards piscivorous interactions but can include other aquatic and terrestrial cases. Avoidance is defined as maneuvering for position by prey, before the predator starts a chase, while evasion is an escape response to an attack. Two separate optimal avoidance methods are found and analyzed—minimizing time within sighting range; and maximizing instantaneous distance. The second method leads to the well-known “fountain effect” of fish school break-up when predators are in the vicinity. The optimal evasion technique involves escape at a small angle (up to 20°) from the heading directly away from the predator. This is in agreement with observations of escaping minnows.
Optimal Avoidance and Evasion Tactics in Predator-Prey Interactions
Weihs, D.; Webb, P. (1984). Optimal Avoidance and Evasion Tactics in Predator-Prey Interactions. Journal of Theoretical Biology, 106(2), 189-206.