Decision-making processes in the collective movements of Przewalski horses: Influences of the environment
Abstract
We investigated decision-making processes in collective movements by observing two families of Przewalski horses (Equus ferus przewalskii) in a semi-free ranging population. We aimed to identify the dynamics of movement patterns according to contexts and to examine how group coordination may be affected by environmental factors. We found that horses rarely failed to keep cohesion. Single-bout and multiple-bout movements were two distinct movement patterns observed in both groups. They were defined by the occurrence of pauses between bouts; they differed by their durations, distances covered, occurring contexts, and social coordination. In single-bout movements, individuals – alone or by subgroups – quickly followed the moves of conspecifics. In contrast, the adhesion of multiple-bout movements was longer when the number of decision-makers and priming behaviours before departure increased. Multiple-bout movements were commonly used to leave restricted access areas and switch to different activities and ecological areas, explaining that horses expressed motivational divergences through different priming behaviours. Our results showed that decision-making in Przewalski horses was based on shared consensus and that they adapted their movement patterns to the environmental context.