Ecological and social influences on the hunting behaviour of wild chimpanzees, Pan troglodytes schweinfurthii

Ian C. Gilby, Lynn E Eberly, Lilian Pintea, Anne E. Pusey

Research output: Contribution to journalArticlepeer-review

86 Scopus citations

Abstract

There has been considerable discussion of the factors that influence the hunting behaviour of male chimpanzees. Explanations invoking social benefits hinge upon the potential for males to share meat with sexually receptive females in exchange for mating ('meat for sex'), or to share meat with other males in exchange for social support ('male social bonding'). Ecological factors may also affect hunting: chimpanzees may hunt more frequently (1) in response to food shortages ('nutrient shortfall'); (2) when energy reserves are high ('nutrient surplus'); (3) in habitat types with good visibility and increased prey vulnerability; and/or (4) when ecological factors favour cooperative hunting. We used 25 years of data on chimpanzees in Gombe National Park, Tanzania, to examine the relative importance of social and ecological factors in the decision to hunt red colobus monkeys, Colobus badius. The presence of sexually receptive females was associated with a significant decrease in hunting probability, suggesting that males face a trade-off between hunting and mating ('meat or sex' rather than 'meat for sex'). Hunting by specific males did not vary with adult male party size, providing evidence against the male social-bonding hypothesis. After controlling for the effects of party size, diet quality was not associated with the probability of hunting or hunting successfully. Hunts were more likely to occur and to succeed in woodland and semideciduous forest than in evergreen forest, emphasizing the importance of visibility and prey mobility. Finally, per capita meat availability decreased with adult male party size, suggesting that hunting was not cooperative. These results provide evidence against social explanations for hunting in favour of more simple ecological alternatives.

Original languageEnglish (US)
Pages (from-to)169-180
Number of pages12
JournalAnimal Behaviour
Volume72
Issue number1
DOIs
StatePublished - Jul 2006

Bibliographical note

Funding Information:
Without the hard work of Jane Goodall and the staff at the Gombe Stream Research Centre, this research would not have been possible. We are especially grateful to Jane Goodall for access to the data, and H. Matama, I. Yahaya, H. Mkono and E. Mpongo for decades of data collection and dedication to the project. We thank the Tanzanian Commission for Science and Technology (COSTECH), the Tanzania Wildlife Research Institute (TAWIRI) and Tanzania National Parks (TANAPA) for permission to continue the ongoing research at Gombe. Thanks to Brian Farm for developing data entry software, to Jane Waterman, Joann Schumacher-Stankey and Jennifer Williams for overseeing data entry, and to the scores of undergraduates and volunteers who entered data. Special thanks to Katie Lee, Kelly Hughes, Anna Wynn and Jason Beyer for helping to extract colobus encounters from the narrative notes. Thanks also to John Carlis for development of the relational database, and to Jin Suong Yoo and Mete Celik for computer programming. We thank Gary Oehlert for continuing his work with the weight data. Richard Wrangham, John Byers and two anonymous referees provided helpful comments on earlier versions of the manuscript. Long-term data collection was supported by the Jane Goodall Institute. Data entry was funded in part by National Science Foundation grants DBS-9021946, SBR-93109909, the College of Biological Sciences of the University of Minnesota, the Jane Goodall Institute, and the Windibrow Foundation. I.C.G. was supported by the L.S.B Leakey Foundation, The University of Minnesota Graduate School and grants from Milton Harris. L.P. was supported by the L.S.B. Leakey Foundation. IKONOS imagery was courtesy of Space Imaging. The research presented here was described under Animal Subject Codes Number 0005A52421, approved by the Institutional Animal Care and Use Committee of the University of Minnesota.

Copyright:
Copyright 2008 Elsevier B.V., All rights reserved.

Fingerprint

Dive into the research topics of 'Ecological and social influences on the hunting behaviour of wild chimpanzees, Pan troglodytes schweinfurthii'. Together they form a unique fingerprint.

Cite this