Western Kentucky University TopSCHOLAR® Masters Theses & Specialist Projects Graduate School Summer 2018 An Evaluation of Deterrent Methods Utilized to Prevent Crop Raiding by African Elephants (Loxodonta Africana) in the Kasigau Wildlife Corridor, Kenya Rebecca Lynn Von Hagen Western Kentucky University, [email protected] Follow this and additional works at: https://digitalcommons.wku.edu/theses Part of the Behavior and Ethology Commons, Natural Resources and Conservation Commons, and the Zoology Commons Recommended Citation Von Hagen, Rebecca Lynn, "An Evaluation of Deterrent Methods Utilized to Prevent Crop Raiding by African Elephants (Loxodonta Africana) in the Kasigau Wildlife Corridor, Kenya" (2018). Masters Theses & Specialist Projects. Paper 3068. https://digitalcommons.wku.edu/theses/3068 This Thesis is brought to you for free and open access by TopSCHOLAR®. It has been accepted for inclusion in Masters Theses & Specialist Projects by an authorized administrator of TopSCHOLAR®. For more information, please contact [email protected]. AN EVALUATION OF DETERRENTS TO PREVENT CROP RAIDING BY AFRICAN ELEPHANTS (LOXODONTA AFRICANA) IN THE KASIGAU WILDLIFE CORRIDOR, KENYA A Thesis Presented to The Faculty of the Department of Biology Western Kentucky University Bowling Green, Kentucky In Partial Fulfillment Of the Requirements for the Degree Master of Science By Rebecca Lynn Von Hagen August 2018 AN EVALUATION OF DETERRENTS TO PREVENT CROP RAIDING BY AFRICAN ELEPHANTS (LOXODONTA AFRICANA) IN THE KASIGAU WILDLIFE CORRIDOR, KENYA ACKNOWLEDGEMENTS The chance to return to academics after such a long absence has truly been the dream of my life, and I have so many people to thank. First and foremost is my husband, without whom none of this would be possible. When he found out it was my desire to return to school and finish my education, he simply made it happen. He has been my rock, enduring long months without me, keeping our home going while I was in Africa chasing elephants and dreams. My friends and family have been more than supportive of me, especially when the way was tough. Dr. Schulte took a chance accepting a non- traditional student into his lab, and his enduring support, patience and genius have caused me to thrive in this academic environment, and I hope we continue to collaborate. My committee of Dr. Nancy Rice and Dr. Michael Stokes have also been a source of inspiration and knowledge, and I have appreciated their input. The graduate school and administrative staff at WKU (ahem, Jessica Dunnegan!) were always there to help with logistics and paperwork, and with over a year spent in Africa, that was no small task. Samantha Thomas also helped keep me sane while navigating the statistical analyses. With such an expansive project, there are several partners to express my undying gratitude toward. I feel the need to point out the irony and pride of being an Earthwatch team member, after spending my teenage years wistfully dreaming while flipping through their catalogs. Stan, Caroline, Kim, & Mary of Earthwatch were helpful beyond measure. In addition, funding from the International Elephant Foundation made this project possible, and I hope our research contributes to the amazing work they continue to support on behalf of the elephants. I also appreciate the support of the iii WKU Graduate School Research Grant committee, the WKU Center for Biodiversity Studies, and the WKU Sisterhood for their financial support. A special thanks to my colleagues in Kenya at Wildlife Works, Dr. Mwangi Githiru, Simon Kasaine, and Bernard Amakobe who constantly taught me about their homeland and culture. Simon allowed me to invade his home for two months when I first arrived and kept a watchful eye to make sure I was safe, while constantly challenging my scientific preconceptions and becoming my dear friend. Jamie, Keith, and Cara, also of Wildlife Works, were the perfect hosts, making sure our team had everything they needed to be successful, including some fun. The rangers of Rukinga Ranch always made sure I felt safe and welcome, especially Joseph, my constant companion during fieldwork. A huge thanks to all my big brothers at Kivuli Camp that kept watch over me and made sure I had everything I needed from such an amazing place, including companionship and snake removal. Thanks also to Dr. Lucy King and her team from Save the Elephants for their collaboration and assistance with our beehive fence project. The Kenyan people, including our participating farmers, made me feel the most welcome and safe of any place I have ever been. I learned from them every day, even if I did not speak the same language. Their resilience and kindness will never be forgotten. Despite the challenges involved in a project like this, the one thing that always grounded me were the times that I was privileged to have close encounters with the elephants. As someone who got a second chance, I will make sure that my work in the future makes a positive contribution towards elephant conservation, while aiding the people that live amongst them. iv CONTENTS Introduction ..........................................................................................................................1 Methods .............................................................................................................................10 Results ................................................................................................................................26 Discussion ...........................................................................................................................30 Literature Cited ...................................................................................................................58 Appendix I: Surveys of Tree Damage as an Indicator of Crop Raiding Fluctuations ......... 69 Appendix II: Elephant Identification and Wildlife Presence Surveys .................................84 Appendix III: Degradation Rates of Capsaicin in Chili Pepper Fences ................................96 v LIST OF FIGURES Figure 1. Characteristic of effective deterrent measures ................................................ 40 Figure 2. A chili pepper fence .......................................................................................... 40 Figure 3. A metal strip fence ............................................................................................ 41 Figure 4. A bee hive fence ............................................................................................... 41 Figure 5. A map of the study area .................................................................................... 42 Figure 6. Field arrangement of experimental blocks at Sasenyi ..................................... 43 Figure 7. Example of an experimental block layout ........................................................ 43 Figure 8. Satellite images of experimental blocks .......................................................... 44 Figure 9. Panel section numbers for experimental fields ............................................... 46 Figure 10. Acacia fence ................................................................................................... 47 Figure 11. Chili fence materials ....................................................................................... 47 Figure 12. Metal control fence ........................................................................................ 48 Figure 13. Examples of crop condition scores ................................................................ 48 Figure 14. Block four reconfiguration ............................................................................. 49 Figure 15. Elephant approaches to deterrents ............................................................... 49 Figure 16. Boxplot of elephant approaches to deterrents in all blocks ........................... 50 Figure 17. Damage to fields by deterrent measure ........................................................ 50 Figure A1.1 Elephant tree damage .................................................................................. 74 Figure A1.2 Tree and wildlife transects established in Rukinga Ranch ........................... 75 Figure A2.1 Example of elephant identification data ...................................................... 90 Figure A3.1 Chili fence lab experiment ........................................................................... 104 vi LIST OF TABLES Table 1. Condition scores for crops ................................................................................. 51 Table 2. All elephant approaches and successful raids ................................................... 52 Table 3. Deterrents and their controls Fisher’s exact results ......................................... 52 Table 4. ANOVA table of elephant approaches .............................................................. 53 Table 5. Tukey test for approaches in relation to blocks ................................................ 53 Table 6. Composition of elephant raiding groups ........................................................... 53 Table 7. Crop damage by crop species, type of damage, and deterrent ........................ 54 Table 8. ANOVA table for crops consumed ..................................................................... 55 Table 9. Tukey test for crops consumed by crop types .................................................. 55 Table 10. ANOVA table for crops trampled ...................................................................