Group size correlates with territory size in European badgers: implications for the resource dispersion hypothesis?

The resource dispersion hypothesis (RDH) predicts that resource heterogeneity can act as a passive cause of group-living in social carnivores and potentially many other species. One central prediction of the RDH is that territory size and group size are not related, as they are determined by resource dispersion and quality, respectively. In this study we investigated the relationship between territory size, group size and group composition in the European badger, a non-cooperative social mustelid whose behavioural ecology was central to the development of the RDH. Using data from a long-term study in the UK, we found that territory size and group size were positively related, contradicting a core prediction of the RDH. Furthermore, territory size was more strongly correlated with the number of adult males in the group than to the number of females or total group size. This result suggests that male badgers may have a more important role in territoriality and receive greater benefits from territory enlargement. These findings are consistent with the predictions of the anti-kleptogamy hypothesis, and suggest that badger territorial and social behaviour is not purely driven by resource dispersion, but may also be associated with breeding behaviour, as in other mustelids.