Spatial structure of foraging meerkat groups is affected by both social and ecological factors

Abstract

Group-living animals need to trade off the benefits and the costs of close proximity to conspecifics. Benefits can be increased, and costs reduced by preferentially choosing specific locations within a group best adjusted to an individual’s needs or by associating with specific group members and/or avoiding others. We investigated the spatial structure of meerkat (Suricata suricatta) groups and whether it was shaped by social factors such as affiliation or aggression among group members, predation risk, foraging success, or a mix of these different factors. Using social network analyses, based on spatial networks, we found associations between the dominant pair, among males and among same aged individuals, and dis-assortment by sex only in one to two of the six groups. In addition, the structure of meerkat groups was highly variable, as individual strength within the calculated networks was not repeatable over time. Meerkats seemed to adjust their location to their physical environment, as dominant individuals were located further toward the front of the group, where foraging success is likely higher and young individuals located further toward the back of the group, where they can benefit most from the vigilance effort of their conspecifics. We conclude that meerkat groups display a dynamic spatial structure depending on both the current social and physical environmental. Group-living animals can achieve greater benefits from close association with conspecifics by choosing specific locations within a group or associating with specific group members and/or avoiding others. A considerable body of work has examined how differences in predation risk or foraging success affect the relative location of individuals within a group. Several studies investigated the association between individuals, in order to draw conclusions on the social structure. However, it is important to disentangle the impact of all of these different aspects on the spatial structure of a group. Here, we provide evidence that both the social and physical environment is important for the spatial assortment of meerkats, a social mongoose foraging in cohesive groups.