Ecology and social behaviour of the Mongolian gerbils, Meriones unguiculatus, at Xilinhot, Inner Mongolia, China (1989)

Agren, G., Zhou, Q., Zhong, W.

Abstract

Observations were made of social and territorial behaviour in a wild high-density population of Mongolian gerbils. The social units were multi-male, multi-female age-structured groups, judged to be families. The operational sex ratio was male biased. Group size varied from two to about 17 animals. Non-overlapping territories were defined by a clustered distribution of burrows, by common areas of activity of group members, and by chases across border zones between the areas used by each group. Territory size was correlated with group size, and ranged from 325 to 1550 m2. Within groups, differential social status was indicated by behaviour patterns of dominant as well as subordinate character. Larger individuals dominated smaller ones, and males usually dominated females. Males ranged more widely and they were generally more active than females. The rate of sexual maturation in subadults varied according to group composition. Mainly the largest reproductively active males defended the territories by chasing, and also by marking along borders. An increased marking rate was observed in reproductively active males and females during oestrus. Three females were observed to copulate, two with more than one male. One female preferentially copulated with a neighbouring male. The functions of territorial defence, marking behaviour and promiscuous mating are discussed, and some cross-species comparisons are made. The present observations are to a large extent compatible with the results of relevant laboratory and seminatural studies.