HABITAT, FOOD AVAILABILITY AND GROUP TERRITORIALITY IN THE EUROPEAN BADGER, MELES-MELES

Since European badgers (Meles meles L.) form non-cooperative groups in parts of their geographic range, but are solitary elsewhere, their so cial systems have been at the centre of a debate about the evolution o f group living in the Carnivora. In a recent review of models of non-c ooperative sociality, Woodroffe and Macdonald (1993) presented evidenc e in favour of two hypotheses, which suggested that badger groups migh t form because either the distribution of blocks of food-rich habitat, or the economics of excavating new setts, prevented the division of g roup territories into individual territories. We present data upon the response of badger spatial organisation to a reduction in food-patch dispersion, brought about by the conversion of earthworm-poor arable l and to earthworm-rich pasture over a 15-year period. This change in th e distribution of earthworm-rich habitats was accompanied by territory fission, facilitated by the excavation of new setts. This indicates t hat the availability of sett sites had not constrained territory size at the start of the study. However, sett distribution did define the s ize and configuration of the daughter territories. We also show that v ariation among territories in the availability of food-rich habitats w as reflected in the reproductive rates and body weights of the groups that inhabited them, although there was no detectable effect upon grou p size.