Evaluating Individual Resilience to Group Perturbation of the Domestic Horse

Abstract

This study aims to investigate individual responses to groupinstability based on established character traits. By using variousmethods of social network analysis, patterns of aggression andsociality were quantified. Instability was induced in a herd ofdomestic horses through perturbing group membership. Two shorttermremovals were performed, followed by a permanent additionof two unknown individuals and the removal of a current groupmember. The short-term removals revealed dynamics of herdresiliency through changes of individual behavior. When theremoved individuals were returned, baseline herd dynamics wereconserved. However, the addition resulted in permanent changesin the herd. The character traits of the added individuals wereimplicated in this group disturbance. This study was able to showthat within a functional herd, an individual’s ability to cope with agroup disturbance is dependent on the character traits of theindividual(s) added or removed. For managers of domesticanimals, understanding the effects of disturbing a herd’smembership is important for promoting group harmony.