Patterns of social grouping in ungulates of Tsavo National Park, Kenya

The paper presents data on group size frequencies and mean group sizes in 11 species of ungulates and, for seven of them, more detailed information on the composition of groups in Tsavo East National Park, Kenya. In several species, mean group size was higher in a part of the study area with more open vegetation. No significant seasonal variations in mean group size were found, except in waterbuck which concentrated markedly in one location during the dry season. Minor local or seasonal variations in the proportions and/or sizes of different group types were evident in most species. In general, grouping patterns were consistent with the type of social organization found in other areas for the species concerned. Frequencies and types of interspecific associations, and the possible factors underlying their formation, are also discussed.