DYNAMICS OF SPACE USE AND MALE VIGOR AMONGST WOOD MICE, APODEMUS-SYLVATICUS, IN THE CEREAL ECOSYSTEM

The spatial organisation of male and female wood mice, Apodemus sylvat icus, was investigated in a large-scale radio-tracking study on arable farmland near Oxford, United Kingdom, during the breeding season. Bot h sexes had significantly larger home ranges in the breeding season th an at other times, and the breeding season home ranges of male (X = 1. 44 ha) were significantly larger than those of females (X = 0.49 ha). Home range overlap was significantly greater between males, and betwee n males and females, than it was between females. Overlap between male s tended to be greatest in heavily utilised areas. Except during sexua l consortship, there was minimal evidence of dynamic interaction among individuals. Home range sizes of breeding males varied widely, as did their body weights. There was no relationship between male body weigh t and home range size or any other movement parameter. However, males with the largest home ranges had the highest scores on all other movem ent parameters, indicating that they expended more energy in movement. These more 'vigorous' males had access to the home ranges of more fem ales than did males with small home ranges.