Diecke Forest in Guinea
In January 1999, we made our first trip to the Diecke Forest (Foret classee de Diecke) in Guinea. This report introduces the forest and points out its potential importance for future research.
Researchers of the Primate Research Institute of Kyoto University have focused on the study of wild chimpanzees at Bossou, Guinea since 1975 (1). Sugiyama and his colleagues have carried out this long-term research to investigate various aspects of these chimpanzees including socioecology, life history, demography, and tool use. The community under study contains about 20 chimpanzees. During this period of 25 years, the minimum size was 16 and the maximum was 23. The core ranging area of the Bossou chimpanzees is about 5-6 square kilometers.
Finding a good research site is a key point for any type of fieldwork. We have tried to find such a place near Bossou for a comparative study of adjacent communities of wild chimpanzees. Since 1993, Matsuzawa and Yamakoshi started preliminary research of chimpanzees in the Nimba mountains of Cote d'Ivoire, about 10 km to southeast of Bossou (2). After long-term negotiations with the Guinean government since 1996, the authors finally got the opportunity this year to make their first trip to the Diecke Forest, about 50 km to the west of Bossou. The Diecke Forest is protected under the name "Foret classee de Diecke", and is more than 700 square kilometers in area, stretching about 35 km to the north-south and about 35 km to the east-west. The forest is under the control of Centre Forestiere de Nzerekore (CF) and is directed by Dr. Cece Papa Conde. It takes about one hour by car from Bossou to Diecke Forest via Lola and Nzerekore. To date there have been very few opportunities for scientific researches in the Diecke Forest. Dr. Rebecca Ham (personal communication) visited the forest as part of a nation-wide census of wild chimpanzees in Guinea. A German project for bio-diversity also made a transect survey of the fauna and flora.
With the assistance of CF and Direction National de la Recherche Scientifique et Technique (DNRST) directed by Dr. Kabine Kante, we conducted a preliminary survey of this forest. The team consisted of Japanese researchers and members from the Guinean authorities CF and DNRST (Dr. Bakary Coulibaly, Dr. Jeremie Koman, and Dr. Cecile Kolamous). We first made a trip around the forest by car, and then entered on foot from two points near the villages of Yossono and Nona. The area is covered mainly by primary forest with numerous small hills, the highest point being 589 m above sea level (similar to Bossou). The landscape of the large Diecke forest looks much like the small Bossou forest, in good contrast to the mountainous Nimba landsape.
While our preliminary survey of three days in the forest was short we found many traces of chimpanzees, feeding traces and sleeping nests. We also heard chimpanzee vocalizations but failed to directly observe them. The most interesting observation for us was that the chimpanzees of Diecke crack open panda (Pandaceae) nuts. A cracking site with stone tools near Nona was littered with the remnants of cracked open panda nut shells. Panda-nut cracking shows a clear difference of tool use from the adjacent communities. The panda nut is not available at Bossou and so it is not cracked. The panda nut is available but there is no evidence of cracking at Nimba. The panda nut is available and cracked by the chimpanzees at Tai, about 250 km away to the south-east of Bossou (3). We also found Coula edulis (Olacaceae) and Elaeis guineensis in the Diecke Forest. Here, according to information from local guides, chimpanzees crack open the coula and oil palm nuts as well as panda nuts.
Future research will be conducted to focus on the cultural diversity among adjacent communities in terms of tool use, behavior, and social structure. This ongoing project will also collect hair samples from nests to analyze the genetic diversity within and between communities. The research was financially supported by the Ministry of Science, Education, and Culture, Japan.

References

1. Sugiyama, Y., Koman, J., 1979. Social structure and dynamics of wild chimpanzees at Bossou, Guinea, Primates, 20, 513-524.
   
2. Matsuzawa, T., Yamakoshi, G., 1996. Comparison of chimpanzee material culture between Bossou and Nimba, West Africa. In. Russon, A., Hard, K., & Parker, S. (eds.) Reaching into Thought: The Mind of the Great Apes. Cambridge University Press, Cambridge, 211-232.
   
3. Boesch, C. Marchesi, P., Marchesi, N., Fruth, B., Joulian, F., 1994. Is nut cracking in wild chimpanzees a cultural behavior? Journal of Human Evolution, 26, 325-338.
   

---

Back to Contents