Poster presentation 12th International Mammalogical Congress

Social networks, friendships, and aggressions in yearling wild boars (Sus scrofa) (#734)

Claudia Bieber 1 , Viktoria Michel 1 , Evelyn Rauchenschwandtner 1 , Sebastian G. Vetter 1
  1. Department of Integrative Biology and Evolution, University of Veterinary Medicine Vienna, Vienna, Austria

Pigs are a highly social and intelligent species. However, studies investigating behavioural questions are usually limited to the domestic pig, while the wild boar is far less well studied. Especially studies investigating the formation and stability of groups in more detail are rare. Here we investigated, via visual observations, social networks, friendships and aggressions among 110 yearling wild boar females kept in an enclosure in Austria. The females were separated from their natal group (four different origins) at the age of approximately 6 months and transferred into two new neighbouring breeding enclosures (33 ha, 19 ha). Densities were ~2 females ha-1 in both enclosures. We observed that the yearling females already formed stable groups with sizes between 16 and 22 individuals. We did not observe a strong linear hierarchy within the groups. Socio-positive interactions occurred more frequently within a group and therefore defined the group. Especially heavy females attacked females outside the group. Interestingly, heavier females seem to support more friendships within the group than lighter group-mates. Our results provide new insights into the social structure of yearling wild boar groups, which seem to occur more frequently under conditions of high hunting pressure in the field. Even young animals without the presence of a leading, old female are able to from stable groups. Females started to reproduce at the age of ~2 years (after this study).