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ABSTRACT ASSESSING SPATIAL AND TEMPORAL PATTERNS OF HUMAN-CAUSED ELEPHANT MORTALITY IN TSAVO EAST NATIONAL PARK, KENYA by Daniel Muteti Kyale Elephant mortality data available for the Tsavo East National Park for the 1990 – 2005 period were used to describe patterns of poaching-induced elephant mortality. Relationships between poaching-induced elephant mortality and human and biophysical factors were also examined. Elephant poaching occurred in clustered patterns and was significantly correlated with land cover, proximity to surface water, ranger patrol bases, park gates, roads, and park boundaries, and elevation. However, none of these factors individually explained more than 40% of the observed variation in poaching induced elephant mortality. These factors were used model risk to elephant poaching based on elephant poaching mortality data for the wet and dry seasons, and on all elephant poaching mortality regardless of season. Risk maps generated can be improved by careful selection of additional risk factors not considered here. These risk maps serve as a useful tool to guide and inform park managers involved in elephant conservation in Kenya. ASSESSING SPATIAL AND TEMPORAL PATTERNS OF HUMAN-CAUSED ELEPHANT MORTALITY IN TSAVO EAST NATIONAL PARK, KENYA A Thesis Submitted to the Faculty of Miami University in partial fulfillment of the requirements for the degree of Master of Arts Department of Geography By Daniel Muteti Kyale Miami University Oxford, Ohio 2006 Approved: Advisor___________________________ (Dr. John K. Maingi) Reader___________________________ (Dr. Kimberly E. Medley) Reader___________________________ (Dr. Mary C. Henry) Table of Contents Page List of Figures……………………………………………………………………iv List of Tables……………………………………………………………………..v Acknowledgements……………………………………………………………...vi CHAPTER ONE…………………………………………………………….……1 1.0 Introduction…………………………………………………………………..1 1.1 Statement of the Problem…………………………………………………..2 1.2 Justification for the Study……………………………………………….…..3 1.3 Research Goal and Objectives…………………………………………….3 1.4 Thesis Organization………………………………………………………....4 CHAPTER TWO………………………………………………………….......….5 2.0 Wildlife Conservation in Kenya……………………………………………..5 2.1 Pre-colonial Period (Before 1895)………………………………………….5 2.2 Colonial Period (1895 - 1963)……………………………………………….6 2.3 Post-Colonial Period (1963 - Present)……………………………………...9 2.4 Kenya Wildlife Service………………………………………………………10 CHAPTER THREE………………………………………………………………14 3.0 Literature Review…………………………………………………………..14 3.1 Spatial Point pattern analysis……………………………………………15 3.1.1 First Order Statistics………………………………………………………16 3.1.1.1 Quadrat Analysis………………………………………………………..16 3.1.1.2 Kernel Density Analysis………………………………………………...18 3.1.1.3 Nearest Neighbor Analysis………………………………………….....19 3.1.1.4 Standard Deviation Ellipse……………………………………………..20 3.1.2 Second Order Statistics…………………………………………………...20 3.2 Human-Caused Wildlife Mortality………………………………………..22 3.3 Land Cover Mapping from Satellite Imagery……… ………………….25 3.4 Research Hypothesis……………………………………………………...27 CHAPTER FOUR……………………………………………………………...…28 4.0 Data and Methods…………………………………………………………..28 ii 4.1 Study Area…………………………………………………………………....28 4.1.1 The Tsavo Elephant Problem…………………………………………....30 4.2 Data…………………………………………………………………………...31 4.2.1 Elephant Mortality Data…………………………………………………...32 4.2.2 Satellite Data…………………………………………………………….....33 4.2.3 GIS Data………………………………………………………………..…..35 4.3 Methods………………………………………………………………………37 4.3.1 Describing Patterns of Human-Induced Elephant Mortality…………...39 4.3.1.1 Quadrat analyses………………………………………………………..39 4.3.1.2 Nearest Neighbor Analyses…………………………………………….40 4.3.1.3 Standard Deviation Ellipse Analyses……………………………….....40 4.3.1.4 Kernel Density Analyses………………………………………………..40 4.3.2 Land Cover Mapping……………………………………………………...41 4.3.2.1 Classification Scheme…………………………………………..……...41 4.3.2.2 Image Classification…………………………………………………….43 4.3.3 Exploring relationships between elephant mortality patterns and biophysical and human variables………………………….……………..44 4.3.4 Generating Risk to Poaching Maps……………………………………...45 CHAPTER FIVE………………………………………………………………….46 5.0 Results and Discussions …………………………………………………46 5.1 Elephant Mortality Analysis Results………………………………….…….46 5.2 Land Cover Mapping………………………………………………….……..54 5.2.1 Accuracy Assessment……………………………………………….…….56 5.3 Relationships between elephant mortality patterns and Biophysical and human factors……………………………….……….……57 5.4 Risk to Poaching Maps………………………………………………………61 CHAPTER SIX……………………………………………………………………69 6.0 Conclusions ………………………………………………………………….69 References……………………………………………..…………………………71 iii List of Tables Table 1: Landsat ETM+ images used in the study……………………………35 Table 2: Categories of mortality datasets used to describe elephant mortality patterns ……………………………………….….39 Table 3: The land cover classification scheme used for the study…………42 Table 4: Quadrat Analysis Results for Poaching-based Mortality…………..46 Table 5: Nearest Neighbor Analysis Results for Poaching-based Mortality……………………………………………..47 Table 6: Sizes (hectares) of Land Cover classes mapped for TENP………56 Table 7: Error matrix for TENP land cover map created from Landsat ETM+ images………………………………………………...57 Table 8: Relationship between elephant mortality and land cover types......58 Table 9: Spearman’s Rank correlates for elephant mortality in TENP..........59 iv List of Figures Figure 1: Map of Kenya showing selected parks and reserves……………..11 Figure 2: Spatial point patterns…………………………………………………15 Figure 3: Location of Tsavo East National Park in Southern Kenya………..29 Figure 4: 2004 Rainfall distribution based on data obtained from TENP records………………………………………………….. 30 Figure 5: Elephant mortality distribution and TENP 10 km buffer…………..33 Figure 6: Landsat WRS-2 Path and Row scene intersections in TENP…...34 Figure 7: GIS layers generated…………………………………………………36 Figure 8: A flowchart of data and methods used in the study……………….38 Figure 9: (a) Images acquired on 3/4/2001 (b) Images acquired on 1/22/2000………………………………………………….….…..41 Figure 10: Kernel Density and Standard Deviation Ellipse Results for Overall Poaching Pattern ……………………………….……...48 Figure 11: Kernel Density and Standard Deviation Ellipse Results for Dry Season Elephant Poaching ………………………………49 Figure 12: Kernel Density and Standard Deviation Ellipse Results for Wet Season Elephant Poaching………………………………50 Figure 13: Kernel Density and Standard Deviation Ellipse Results for 1990 – 1997 Elephant Poaching Period……………………...52 Figure 14: Kernel Density and Standard Deviation Ellipse Results for 1998 – 2005 Elephant Poaching Period...…………………....53 Figure 15: Land Cover Map for TENP………………………………………….55 Figure 16: Relationship between dry season poaching and distance to main rivers……………………………………………...61 Figure 17: Risk to elephant poaching surface for Wet Season……………...63 Figure 18: Risk to elephant poaching surface for Dry Season………………65 Figure 19: Annual Risk to Elephant Poaching………………………………...67 v Acknowledgements I feel indebted to the department of Geography for granting me the opportunity for training experience in Miami University and Kenya Wildlife Service for allowing me study leave to further my studies. I sincerely thank Dr. John Maingi for his academic advising, inspiring ideas and for always finding an extra minute to address issues arising during the thesis process. I also thank Dr. Kimberly Medley and Dr. Mary Henry for their constructive inputs into the thesis and the various staff in Kenya Wildlife Service who helped in one way or another during my fieldwork in Kenya. Finally I register my special thanks to the departments of Geography and Zoology for their financial support that enabled me to conduct my fieldwork in Kenya. vi CHAPTER ONE 1.0 Introduction Kenya’s tourism is founded on the country’s rich wildlife resources and contributes to approximately 20% of the Gross Domestic Product (Government of Kenya, 2005). In 2005, Kenya earned Kshs. 49 billion (US$ 677 million) up from Kshs. 42 billion earned in 2004 and it is projected that the tourism sector will earn the country Kshs. 56 billion by the end of 2006 (Odhiambo and Moraa, 2006). The contribution of the African elephant to nature-based tourism cannot be overlooked being a member of the “Big Five” family (elephant, rhino, lion, buffalo and leopard) that forms a star tourist attraction in sub-Saharan Africa. Additionally, African elephants are the largest terrestrial animals and keystone species whose feeding behaviors have contributed to maintaining African savannah ecosystems (Wijgaarden, 1985; Leuthold, 1996; Western and Maitumo, 2004). Elephant populations especially in eastern Africa had declined over the years due to human activities. Although loss of habitat to agriculture and human settlements (Turner et al., 2001; Makonjio and Warui, 2004) has been argued as a major long-term threat to the survival of elephants in situ, the ultimate direct threat to elephant survival has been identified as poaching (Western, 1987; Leader-Williams et al., 1990; Armbruster and Lande, 1993; Burton, 1999; Heltberg, 2001). Organized poaching had been responsible for the downfall of elephant populations in their natural ranges in Africa (Futurist, 1987), which necessitated the Convention on International Trade in Endangered Species of Flora and Fauna (CITES) to ban ivory trade in 1987. CITES believed that a ban on ivory trade would afford the elephant population a chance to recover from years of massive slaughter. Currently, however, the question of how best to conserve