Do sheep (Ovis aries) perform third‐party interventions?

Abstract

AbstractMost ungulate mammals are social species that live in large groups where agonistic encounters with con‐specifics are common. Such interactions may be a source of distress and can pose a threat to group's cohesion. Group stability may be achieved by third‐party interventions, defined as the behavior of individuals (interveners) interrupting agonistic interactions between two con‐specifics through direct physical contact, interposition, or threats. This can be costly for the intervener but may lead to benefits like reciprocity, group cohesion, and enhance lifetime fitness. The study investigated whether sheep (Ovis aries) perform third‐party interventions. Adult rams (n = 13) reared under intensive farming were observed during three different periods (A, B, C). At period A, rams formed one stable group of eight individuals. Period B started when five familiar rams returned to the group simultaneously and period C, when rams formed one stable group of 13 individuals. Scan sampling was used to record close proximity. Social behaviours between individuals were collectedad libitumto increase the number of social interactions because of the low‐sample size. In total, 125 interventions occurred. Interventions were higher in period B (N = 69; frequency = 2.55) followed by period C (N = 45; frequency = 0.56) and period A (N = 12; frequency = 0.18). Only a few individuals played a crucial role in performing this behaviour. Interventions were positively correlated with agonistic interactions. Interveners were high or middle ranked, rose faster in the social hierarchy and spent more time in social proximity. The supported animals performed more frequent affiliative behaviors. The study presents preliminary evidence of third‐party interventions in agonistic encounters of sheep, suggesting that such behaviour may act as a preventive tool towards the disruption of group stability, by enhancing long‐term fitness of interveners and supported individuals and providing valuable information for sheep welfare.