Preliminary information of the pygmy chimpanzees (Pan paniscus) of the Congo basin

Local information was collected on the ecology of pygmy chimpanzees in the Lac Tumba Region, Zaire. Population density very small; habitat, secondary swamp forest with occasional trespass of esobe grassland; locomotion, quadrupedal walking on the ground; diet, primarily frugivorous and vegetarian, but insects, honey and fish consumed. Many kinds of cultivated plants also eaten; sleeping nest built in a tree in the same fashion as ordinary chimpanzees; group size fairly large, from 15–20 to 40 head; human persecution very severe. It proved possible to make a field study of the species in this region.The research was financially supported by the Japan Society for the Promotion of Science, Tokyo.