Ranging patterns in white rhinoceros, Ceratotherium simum simum: implications for mating strategies

How animals use space has important consequences for feeding ecology, social organization, mating strategies and conservation management. In white rhinoceros, female home ranges are much larger than male territories, suggesting that movement patterns are influenced by factors other than resource distribution. In this study we placed radiotransmitters on 15 female white rhinoceros, recording 1758 locations and collecting behavioural data during 1671 observation sessions, making this the largest data set of its kind in this species. We investigated how habitat variables and male territories influenced female movement and reproductive behaviour. Female home ranges were approximately 20 km2 and core areas were 5 km2, with male territories roughly the same size as female core areas. Female range size did not vary with season, but the pattern of space use did vary. Females used grassland habitat preferentially, utilizing these areas significantly more than expected based on availability. Findings relevant to the mating strategy include: (1) the amount of grassland in a male's territory predicted female use of the territory; (2) the time that a female spent in a male's territory was a significant predictor of reproductive activity with the male, indicating that females probably mate with the most familiar male; and (3) the temporal pattern of female space use suggests that females did not increase mate sampling behaviour nor did they become more choosy about which males they visited when reproductively active. These findings suggest that males may maximize reproductive success by defending areas containing more grassland habitat.