Two closely related species of diurnal ground squirrels inhabit southern Africa. Although the morphological similarity of these species makes them difficult to distinguish in the field, evidence suggests that their social systems are extremely different. The Cape ground squirrel (Xerus inauris) is a highly social species inhabiting open areas in arid regions across southern Africa (Waterman 1995). This high degree of sociality appears to be the result of predation pressure (Waterman 1995, 1997). Although predation appears to be the primary selective force leading to sociality in this species, differential resource abundance may influence the type of sociality and life-history exhibited. In areas with low resources, competition for food resources may limit the sizes of groups (Waterman 2002). In areas of high resources, Cape ground squirrels may live in large groups composed of several female social groups (Herzig-Straschil 1978). These observations suggest that the social system in this species may be fairly plastic, varying with abundance of available resources, yet this hypothesis has not been examined. Specifically, very little is known about the biology of Cape ground squirrels in the South West Arid region in Namibia, where resources are especially limiting or in central South Africa, where resources are more abundant. The main objective of this research is examine the biology of Cape ground squirrels to assess the hypotheses that resources or predation are the main constraints on grouping in this species. The specific research goals for this past year included 1) continue general trapping and monitoring of the populations, and 2) collection of morphometric data on removed animals.