CRITICAL THREATS to ASIAN ELEPHANT HABITAT in SRI LANKAN PROTECTED AREAS Christie Sampson Clemson University, [email protected]
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Clemson University TigerPrints All Theses Theses 12-2013 CONSERVING THE LAND OF THE GIANTS: CRITICAL THREATS TO ASIAN ELEPHANT HABITAT IN SRI LANKAN PROTECTED AREAS Christie Sampson Clemson University, [email protected] Follow this and additional works at: https://tigerprints.clemson.edu/all_theses Part of the Ecology and Evolutionary Biology Commons Recommended Citation Sampson, Christie, "CONSERVING THE LAND OF THE GIANTS: CRITICAL THREATS TO ASIAN ELEPHANT HABITAT IN SRI LANKAN PROTECTED AREAS" (2013). All Theses. 1789. https://tigerprints.clemson.edu/all_theses/1789 This Thesis is brought to you for free and open access by the Theses at TigerPrints. It has been accepted for inclusion in All Theses by an authorized administrator of TigerPrints. For more information, please contact [email protected]. CONSERVING THE LAND OF THE GIANTS: CRITICAL THREATS TO ASIAN ELEPHANT HABITAT IN SRI LANKAN PROTECTED AREAS A Thesis Presented to the Graduate School of Clemson University In Partial Fulfillment of the Requirements for the Degree Master of Science Biological Sciences By Christie Lynn Sampson December 2013 Accepted by: Dr. David Tonkyn, Committee Chair Dr. Saara DeWalt Dr. Peter Leimgruber i ABSTRACT Grasslands habitats are hypothesized to be a critical resource for the endangered Asian elephant (Elephas maximus) throughout its range. However, this hypothesis has not been rigorously tested. My study examined elephant habitat selection in Sri Lanka to determine the importance of grassland versus other local habitats, and how livestock abundance, fire, and the invasive plant Lantana camara affect the relative abundance of elephants within habitats. My research was conducted in two protected areas in Sri Lanka, Udawalawe National Park (UNP) and Hurulu Forest Reserve (HR). I used distance- sampling on a total of 50.8 km of dung line-transects in the four habitat types and under burnt and unburnt conditions to assess relative abundance of elephant and livestock populations. I also established 197 permanent vegetation plots in UNP and HR to determine plant composition and the extent of L. camara invasion. I found that relative elephant abundance is highest in grasslands, specifically areas with Panicum maximum. I found no significant difference in the abundance of elephants in burnt vs. unburnt habitats; however, livestock abundance is greater in recently burnt areas. Livestock and elephant populations are often found in the same habitat, indicating they may be competing for food resources. I conclude that grasslands are essential habitat for Asian elephants in Sri Lanka and that stopping illegal grazing and the spread of L. camara in protected areas should be considered vital components of future conservation efforts. ii DEDICATION I dedicate this manuscript to my family. ACKNOWLEDGMENTS First, I would like to thank my advisor Dr. David Tonkyn for all of his support over the past three years. And my graduate career would not have been possible without Dr. Peter Leimgruber who gave me the opportunity to work on this project. Thank you to Dr. Saara DeWalt for her analysis help and writing critiques. I am indebted to Dr. Pruthu Fernando, Dr. Jenny Pastorini and the entire Centre for Conservation and Research team for all of their help and guidance. Thank you to my field crew, Nishantha, Sanka, and especially H.G. Janaka, who worked tirelessly with me in Sri Lanka and the interns at the Smithsonian GIS lab for all of their assistance. The study was made possible with funding from the Smithsonian Institution and the United States Fish and Wildlife Asian Elephant Conservation Fund (# F11AP00263). And finally, a big thank you to my friends and family. iii TABLE OF CONTENTS Page TITLE PAGE ........................................................................................................................ i ABSTRACT ......................................................................................................................... ii DEDICATION .................................................................................................................... iii ACKNOWLEDGMENTS ..................................................................................................... iii LIST OF TABLES ................................................................................................................ vi LIST OF FIGURES ............................................................................................................. vii CHAPTER I. BACKGROUND ................................................................................................ 1 II. CRITICAL THREATS TO ASIAN ELEPHANT HABITAT IN SRI LANKAN PROTECTED AREAS .............................................................. 5 Introduction ................................................................................................... 5 Methods ......................................................................................................... 9 Study sites ................................................................................................ 9 Elephant and livestock relative abundance survey design .................... 10 Vegetation survey design ....................................................................... 14 Vegetation plot sampling ....................................................................... 14 Intensive vegetation sampling ............................................................... 15 Timing of surveys ................................................................................... 15 Data Analysis ................................................................................................ 16 Elephant and livestock relative abundance ........................................... 16 Vegetation .............................................................................................. 17 Models ................................................................................................... 18 Spatial Analysis ............................................................................................. 18 Fire ......................................................................................................... 20 Models ................................................................................................... 21 iv Table of Contents (Continued) Results .......................................................................................................... 22 Dung decay ............................................................................................. 22 Elephant and livestock relative abundance ........................................... 22 Plant community .................................................................................... 23 Fire response of plant species ............................................................... 27 PCA ......................................................................................................... 29 Models ................................................................................................... 29 Discussion..................................................................................................... 33 Conclusion .................................................................................................... 39 Appendices ................................................................................................... 41 1: Study sites ..................................................................................... 42 2: Habitat type examples .................................................................. 43 3: Detailed survey information ......................................................... 44 4: Vegetation plot ............................................................................. 45 5: Plant species ................................................................................. 46 6: Habitat classification ..................................................................... 47 7: Correlation matrices ..................................................................... 49 8: PCA plot of Udawalawe National Park .......................................... 53 9: PCA plot of Hurulu Forest Reserve ............................................... 54 References ................................................................................................... 55 III. LANTANA camara: ALTERING FIRE IN AN ECOSYSTEM ................................ 61 Exotic plants around the world .................................................................... 61 Lantana camara ........................................................................................... 62 Origin ...................................................................................................... 62 Lantana camara and fire ....................................................................... 63 Post-fire regeneration of Lantana camara .................................................. 65 Seed regeneration .................................................................................. 66 Vegetative regeneration ........................................................................ 67 Alleopathy .............................................................................................. 68 v Table of Contents (Continued) Lantana camara and development ............................................................. 69 Herbivores and Lantana camara ................................................................