Behavioural response of prey to repeated attacks by non-coordinating predators.

Collective behaviour is a ubiquitous phenomenon entailing the emergence of fascinating pattern formations in organisms. Reduction of predation risk is presumed to be a major factor contributing towards the evolution of such behaviour. However, the effect of persistent attacks by multiple predators on the behavioural response of the prey remains largely unexplored. The current work aims to address this issue using an agent-based approach employing an underdamped Langevin model. A continuous transition in prey response from a cohesive escape to split-and-escape is discussed with respect to the angular configuration of the predators before the attack. The statistics show that the attack on the nearest prey is the most successful pursuit strategy, while alternative strategies, such as attacking the centre of the group, have conspicuous ancillary effects, such as group splitting. A long-term temporal study of the system indicates a counter-intuitive faster decay of prey numbers at higher intensity of prey coordination, hinting at possible excess alignment and its detrimental effects in the case of successive predator attacks. The effect of predation is found to be non-additive even if non-coordinating predators are considered, highlighting the non-scalability of predator-prey systems and urging further scrutiny of the dynamics of group hunting in such systems.