Rodents in tropical Africa have been recognized for decades both as important pests of agriculture and as reservoirs of numerous diseases that affect humans and livestock (Keesing 2000). Despite this recognition, however, little is known about the ecology and behaviour of these abundant and widespread animals. Because the impacts of small mammals as pests are expected to be some function of their population density, most ecological research on African rodents has focused on their population dynamics (Delany 1972, 1986; Leirs et al. 1994, 1996a).