, Volume 45, Issue 4, pp 211–219 | Cite as

Fruit availability and chimpanzee party size at Kahuzi montane forest, Democratic Republic of Congo

  • A. Kanyunyi BasaboseEmail author
Original Article


The effect of fruit availability on chimpanzee party size was investigated in the montane forest of Kahuzi. Seasonal variation in both fruit availability and party size was examined. Fruit abundance per se does not affect chimpanzee party size. However, seasonality and distribution patterns of fruits are both determinant ecological factors that control the size of chimpanzee parties at Kahuzi. There was no correlation between fruit abundance and the spatial distribution of fruits. When fruits were clumped and available in large amounts for a long period, chimpanzee party size increased, or otherwise decreased when fruits were highly available for only a limited period. Tree species that produced only a small amount of ripe fruit throughout the year did not affect the foraging party size of chimpanzees. Temporal and spatial variability in fruit abundance seems to constrain grouping patterns of chimpanzees at Kahuzi more so than in other chimpanzee habitats previously described.


Fruit availability Seasonality Party size Chimpanzee Kahuzi montane forest 



This study was financed by the International Scientific Research Program of Japan (No. 08041146 to Prof. J. Yamagiwa) in cooperation with CRSN (Centre de Recherche en Sciences Naturelles) in the Democratic Republic of Congo. I thank Prof. J. Yamagiwa for his supervision during my field research at Kahuzi. I would like to thank ICCN (Institut Congolais pour la Conservation de la Nature) for granting permission to carry out this study in its National Park. Thanks are also due to Prof. S. Bashwira, Dr. M. Nshombo, Dr. B. Baluku, Mr. B. Kasereka, Mr. M.O. Mankoto, and Ms. S. Mbake for their administrative help. I am grateful to Mr. K. Kaleme, Mr. M. Bitsibu, Mr. S. Kamungu and all of the guides and guards of Kahuzi-Biega National Park for their technical help. Thanks are also extended to Prof. M.A. Huffman and two anonymous reviewers for helpful comments on earlier versions of this manuscript.


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Copyright information

© Japan Monkey Centre and Springer-Verlag 2004

Authors and Affiliations

  1. 1.Centre de Recherche en Sciences NaturellesLwiroDemocratic Republic of Congo

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