Evidence of leaf swallowing, a proposed form of medicinal plant use by savanna chimpanzees was recently recorded at the Fongoli study site in southeastern Senegal. Since April 2001, the Fongoli community of chimpanzees has been studied in an effort to better understand the ecology of chimpanzees in an arid environment. The habitat can be described as a mosaic of woodland and savanna containing areas of bamboo forest and grassland and interspersed with isolated areas of gallery forest (<1% of study area) and larger areas of laterite plateau. Chimpanzees at this site have been estimated to occur at a density of 0.09 individuals per km² (1). The site lies approximately 40 km E of the Parc National du Niokolo Koba and 10 km NW of the town of Kedougou, in southeastern Senegal.