HOME-RANGE SIZE IN RELATION TO AGE AND SEX IN MOOSE

During 1983-1989, 49 moose (Alces alces) were monitored in central Swe den to estimate annual and seasonal home ranges. Males had larger annu al home ranges (25.9 km2 +/- 3.3 SE) than did females (13.7 km2 +/- 2. 2 SE, P < 0.01). Size of home ranges of males was strongly dependent o n age (P < 0.05), in contrast to that of females (P < 0.20). We observ ed similar home-range sizes (10-20 km2) among younger male and female moose, whereas older males used larger home ranges than did older fema les, especially during autumn (P < 0.01) and winter (P < 0.01). Neithe r sex showed significant variation in home-range size among seasons (P > 0.05), except females without young (P < 0.05). Only in autumn did females with young have different (P < 0.01) average home-range size c ompared with females without young; those with young were, on average, twice as large as those without young (5.8 km2 versus 2.2 km2, respec tively). We suggest that variation in home-range size may have two mai n causes. First, body size, and thus nutritional demands, varies betwe en sexes throughout the year; second, the strong relationship between age and home-range size among males is likely caused by social activit ies associated with rut, and, in particular with age-related dominance .