Movement decision-making in plains zebra (Equus burchelli)

摘要

It is by their movements that animals both react to and change their physical and social environment, and that of the species with which they interact. I examine the movement decision-making of plains zebra (Equus burchelli ) in Laikipia, Kenya. I present case studies on zebras' responses to predation danger and experimental loss of resources, as well as the factors shaping individual roles in collective decisions.;As an important prey species for lions (Panthera leo), zebras adapt their behavior to avoid predation. Zebras avoid specific habitat patches when lions are present. They also modify their movement patterns in the times of day and habitats of greatest danger. Danger is highest in grassland during the night, when lions are more active. Zebras reduce their grassland use at night, instead using more woodland. When in grassland at night, zebras move faster and take sharper turns, a movement style hypothesized to assist zebras in avoiding capture.;Inhabiting a landscape of fluctuating resources, zebras may be expected to seek information about locations that have recently been unrewarding. I investigated zebras responses to experimental removal of water from a preferred water hole. Zebras returned more rapidly to a water hole, following an unsuccessful visit, than they did following a rewarding experience. I detect no effect of the water hole's state during the previous visit on the frequency with which an individual used alternative water holes. I conclude that zebras returned more rapidly to the empty water hole because they were curious about the novel condition.;In zebra and other social animals, movement responses of the group emerge from the interactions of individuals. I investigate leadership in tightly-knit harems and loosely bonded herds of multiple harems. I find that harem females tend to have habitual roles in the initiation of harem movement. In herds, however, we find no harems that consistently lead other harems. Thus stable relationships appear to be a prerequisite for consistent leadership roles to develop. At both levels of social organization, lactation results in a greater tendency to lead. For lactating females, one benefit of leading is preferential access to scarce water.