Social organisation and movements of topi (Damaliscus korrigum) during the rut, at Ishasha, Queen Elizabeth Park, Uganda

Abstract

Topi, on which there have been few previous studies, were investigated in order to understand the manner in which they use open grassland and to provide data for comparison with other Alcelaphines. The mobile mode of existence of topi at Ishasha provided a special interest. About 4 000 topi were using the 80 km² of savanna. They comprised a single congregation and individuals grazed in all parts of the range as members of moving and changing aggregations that split and amalgamated freely. All females, accompanied by 6-month-old calves were organized into a mosaic of ‘harem’ groups, each tended by a herdmaster bull. These groups were temporary and females were constantly escaping from one bull's sphere of influence or ‘ward’ to join another. The bulls maintained a network of wards and displayed antagonistically towards one another. They also excluded other males which formed loose arrays at the periphery of the aggregations. Where herdmaster bulls had lost all females from their wards they dropped their status for a while and joined peripheral males. Age at puberty, and the activities of the several age-classes of topi are described.