Multi-Scale Assessment Of Habitat Use By Black Rhinos (Diceros Bicornis Bicornis Linnaeus 1758) In Northwest Namibia

TABLE OF CONTENTS

Contents i

List of figures vi

List of tables viii

Acknowledgments ix

Abstract x

Declaration xi

CHAPTER 1 1

1. INTRODUCTION 1

1.1 General introduction 1

1.2 Problem statement 3

1.3 Specific objectives 4

1.4 Key questions 4

1.5 Research predictions 5

CHAPTER 2 8

2. LITERATURE REVIEW 8

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2.1 Background on black rhinoceros 8

2.2 Distribution of black rhinoceros: historical and current range 9

2.3 Conservation and management 10

2.4 General ecology and habitat preferences 12

2.5 Browse availability 13

2.6 Namibia’s desert-adapted black rhinos 14

CHAPTER 3 17

3. MATERIALS AND METHODS 17

3.1 Study area 17

3.2 Climate 20

3.3 Geomorphology 21

3.4 Flora and fauna 21

3.5 Specific study sites 22

3.6 Sampling design and plot demarcation 25

3.7 Data collection 26

3.7.1 Plant inventories 26

3.7.2 Measurement of browse availability 26

3.7.3 Black rhino habitat use level in relation to landscape variables 27

3.7.4 Determination of landscape variables 28

3

3.8 Data manipulation and analysis 29

3.8.1 Species diversity and richness 29

3.8.2 Comparison of species composition 30

3.8.3 Browse availability 30

3.8.4 Influence of environmental variables on browse availability of

selected plant species 31

3.8.5 Influence of environmental variables on the probability habitat use

by black rhino: Landscape scale 32

CHAPTER 4 34

4. RESULTS 34

4.1 Species diversity and richness 34

4.2 Species composition 36

4.3 Browse availability 40

4.4 Browse availability of selected plant species 45

4.5 Habitat use by black rhinos in relation to environmental variables

in Palmwag concession 47

CHAPTER 5 58

5. DISCUSSION 58

5.1 Species diversity, richness and composition 59

5.1.1 Influence of rainfall 59

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5.1.2 Influence of soil characteristics 60

5.1.3 Influence of elevation 62

5.1.4 Influence of land use 64

5.2 Browse availability 66

5.2.1 Influence of rainfall on browse availability 67

5.2.2 Influence of elevation on browse availability 68

5.2.3 Presence of other browsers: livestock and wild animals 70

5.2.4 Influence of other factors on browse availability 68

5.3 Probability of habitat use by black rhinos 71

6. CONCLUSIONS AND RECOMMENDATIONS 76

6.1 Conclusions 76

6.2 Recommendations 77

REFERENCES 79

APPENDICES

APPENDIX 1: Sampling points in ≠Khoadi //Hoas conservancy 91

APPENDIX 2: Sampling points in Torra conservancy 92

APPENDIX 3: Sampling points in Palmwag concession 93

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APPENDIX 4: Vegetation sampling sheet 94

APPENDIX 5: List of selected preferred plant species by black rhinos 95

APPENDIX 6: Species diversity indices 96

APPENDIX 7: Number of species 100

APPENDIX 8: Browse availability 102

APPENDIX 9: Mean annual rainfall ranges 106