Predicting conflict over scarce resources: Chimpanzees ( Pan troglodytes verus ) and Ful ɓe pastoralists by Brooke E. Massa Dr. Jennifer Swenson, Advisor May 2011 Masters project submitted in partial fulfillment of the requirements for the Master of Environmental Management degree in the Nicholas School of the Environment of Duke University 2011 MP Advisor's signature Cover photo: A pruned Khaya senegalensis tree stands, surrounded by its cut branches. Also known as African mahogany , the tree is prized not only for the fodder it provides, but also as a strong wood, often used to craft farming tools. Khaya senegalensis is considered a vulnerable species by the IUCN and is protected by several West African governments. 2 Abstract The western chimpanzee ( Pan troglodytes verus ) is considered the most endangered subspecies of chimpanzee. The populations living at the furthest extent of its range, in southern Senegal – a country situated directly south of the Sahara Desert - are considered to be nearly extinct. These ‘savanna chimpanzees’ have adapted to living in an arid environment and are now facing more threats to their survival as climate change and deforestation have forced nomadic pastoralists further into their habitat in search of fodder and water. Combining field-collected data on both chimpanzee and pastoralist habitat use with GIS and remote sensing data, I spatially predicted areas of potential habitat conflict among chimpanzees and pastoralists. Using species distribution modeling, I found that large swaths of forested habitat in Bandafassi are predicted to be used by nomadic pastoralists. Their presence is expected in 86 percent of the land which is predicted to be used by chimpanzees. Statistical modeling using the Dirichlet distribution predicted overuse of gallery forests by herders. Since herders remove most of the crowns of 9 species of trees, 7 of which provide important resources for chimpanzees, the impact of herders on chimpanzee resources is likely detrimental. Strategies to protect chimpanzee habitat and increase resources for herders should be considered in community-based conservation projects. 3 Acknowledgements Thank you to the Republic of Senegal and the communities of Bandafassi, Indar, and Etiouar for allowing me to conduct research in their forests. I wish to thank all of those who helped me with my project: first, my advisor, Dr. Jennifer Swenson for her endless patience with my project and supportive inestimable guidance in geospatial analysis and remote sensing; secondly, Dr. Jill Pruetz for giving me a focus for my research and guiding me to Bandafassi; thirdly, Dr. Song Qian for his thoughtful analysis of my research question and data; and lastly, but certainly not least, Soumalaye Gilbert Camara for his invaluable expertise and guidance in the field. Without any one of these people, my project would not have materialized. Also, thanks go to Brittney Baker and Taryn Thompson for contributing work to the Dirichlet model; and John Fay and Mariano Gonzalez Roglich for helping me figure out some issues in ArcGIS. Thanks and love also go to my wonderful family and friends - especially Amidou Keita, Michele Lehman, and Ouseman Kante for keeping me company when I wasn’t in the field (and for helping me get to Kedougou in the first place!!). And, lastly, to my love Derwin Dubose, thank you for all of your encouragement and support. The research was generously funded by The David R. Brower Endowment Fund, Student International Discussion Group – Lazar Foundation, and the Nicholas School International Internship Fund; I thank you for your support. 4 Table of Contents Abstract ......................................................................................................................................................... 3 Acknowledgements ....................................................................................................................................... 4 Table of Figures ............................................................................................................................................. 6 Abbreviations ................................................................................................................................................ 7 Introduction .................................................................................................................................................. 9 Importance and History of Chimpanzee Conservation ............................................................................. 9 Background on Community-based Conservation ................................................................................... 14 Community-based Conservation Work in Africa Today .......................................................................... 18 Chimpanzee Conservation in Senegal ..................................................................................................... 20 Methods ...................................................................................................................................................... 29 Site Description ....................................................................................................................................... 29 Data ......................................................................................................................................................... 32 Data Collection ........................................................................................................................................ 32 Geospatial Analysis: Species Distribution Modeling ............................................................................... 37 Point Occurrences ............................................................................................................................... 37 Environmental Predictors ................................................................................................................... 38 Statistical Analysis of Habitat Use ........................................................................................................... 43 Results ......................................................................................................................................................... 45 Which species of trees are the herders using for fodder? ..................................................................... 45 Species Distribution Modeling ................................................................................................................ 46 What habitats are preferred by each group? ..................................................................................... 46 Is there overlap between the herders’ preferences and chimpanzee preferences? ......................... 52 Statistical Analysis of Habitat Use ........................................................................................................... 53 What habitats are preferred by each group? ..................................................................................... 53 Is there overlap between the herders’ preferences and chimpanzee preferences? ......................... 56 Discussion.................................................................................................................................................... 58 Considerations and Recommendations for Management ...................................................................... 66 5 Conclusion ................................................................................................................................................... 73 Works Cited ................................................................................................................................................. 74 Appendices .................................................................................................................................................. 83 Appendix 1: Additional Information on Dirichlet Model ........................................................................ 83 R Script and Output ............................................................................................................................. 83 Appendix 2: Additional Information on Geospatial Analysis ................................................................. 86 Classification ....................................................................................................................................... 86 ArcGIS Models and Scripts .................................................................................................................. 89 Maxent ver. 3.3.1 Output ................................................................................................................... 97 Table of Figures Figure 1 . Niokolo-Koba National Park lies in the southeastern corner of Senegal. .................................... 20 Figure 2. Senegal's land use is dominated by rainfed agriculture. Chimpanzees live in the southeastern corner of the country where the shrubland begins to be more forested. The expansion of rainfed and irrigated croplands has depleted the amount of grasslands available to pastoralists for grazing. Data is from the Global Land Cover Characteristics (version 2, 2008), courtesy of the U.S. Geological Survey. ... 24 Figure 3. Annual precipitation regimes vary along a gradient from north to south in West Africa (Data from Bioclim: Hijmans, et al., 2005)...........................................................................................................