Tool-use by chimpanzees (Pan t. troglodytes) in the Lopé Reserve, Gabon

Abstract

During a long-term study of chimpanzees in the Lope Reserve, Gabon, tool-use to obtain insects or their products was observed four times and on 23 other occasions tools made and used by chimpanzees were recovered. Of 144 tools used to obtain insects, 142 were made from woody material. Tools varied in dimensions and in the degree of modification (bark stripping and fraying of ends) but those used to obtain different prey species were generally similar and resembled tools described from other chimpanzee populations in central Africa. Use of a leaf “sponge” to obtain water from a hole in the branch of a tree was observed once. Four tool-use patterns shown by other chimpanzee populations appeared to be absent at Lope as no direct or indirect evidence of their existence was obtained in ten years.