Feeding ecology of three frugivorous civets in Borneo( Title Dissertation_全文 ) Author(s) Nakabayashi, Miyabi Citation 京都大学 Issue Date 2015-03-23 URL https://doi.org/10.14989/doctor.k18842 学位規則第9条第2項により要約公開; 許諾条件により本文 Right は2018-09-14に公開 Type Thesis or Dissertation Textversion ETD Kyoto University Feeding ecology of three frugivorous civets in Borneo ボルネオ島に生息する果実食性シベット 3 種の採食生態 Thesis for a doctoral degree at The Graduate School of Science, Kyoto University Miyabi Nakabayashi Wildlife Research Center of Kyoto University March 2015 1 Summary Background In this study, I investigated feeding ecology of three sympatric species of frugivorous civets, namely the common palm civet Paradoxurus hermaphroditus, the small-toothed palm civet Arctogalidia trivirgata, and the binturong Arctictis binturong in Bornean rainforests. They possess typical carnivorous dental morphology such as sharp canines and carnassial teeth, and noticeably short gastrointestinal guts which are suitable for carnivory. Due to these morphological constraints on frugivory, frugivorous civets seem to confront with a difficulty in effective digestion of fruits. Morpho-physiological disadvantage is inevitable for them, and then, they may exhibit behavioural adaptation to frugivory. Evaluating feeding ecology of the tree civet species, I discussed the characteristics of their feeding ecology and the coexistence mechanism of the three sympatric civet species Methods I investigated feeding ecologies of the three civet species in terms of their diets and habitat preferences by intensive field study and laboratory works. I researched on their diet, physical and nutritional characteristic of food fruits, and fruit preference in inter-species 1 and intra-tree level. Additionally, I studied on horizontal and vertical habitat uses. After I described them, I evaluated the characteristics of frugivorous civets by comparing their feeding behaviours in fruiting trees and fruit type they feed on with those of other frugivorous animals; three primate species and two hornbill species. Regarding coexistence mechanism of three sympatric civet species, I compared the diet and habitat preference of each species. Results and Discussion The results indicate that all the frugivorous civets feed on sugar-rich soft-pulped fruits rather than lipid-rich soft-pulped fruits at night, and figs are predominant diet in the binturong. The wide and short gut of the frugivorous civets occasions low surface area/ gut volume ratio, restricting absorption of lipid. Conversely, absorption of simple soluble sugars may be more efficient. All frugivores such as primates and hornbills in Borneo can be competitors of the frugivorous civets because they consume the same fruit types, yet contest competition to food resources could be avoided by the differences in active time. These habits may enable them to maintain their population even though they possess disadvantageous morphology to frugivory. The results also indicate that the three frugivorous civet species inhabit the same area, yet they have different diets and habitat preferences. The binturong largely depended 1 on fig fruits even though fig trees were not so common. Although the two species of palm civets have similarity in their foods and habitat preferences as both of them preferentially use fruits of pioneer plants and forests around canopy openings in their active time, the common palm civet feeds on sugar-rich fruits whilst the small-toothed palm civet does unripe fruits, floral nectar, and bark sap besides sugar-rich fruits. In addition, only the common palm civet forages on the ground. These differences in diet and habitat use may enable them to coexist even in a small scale. 1 Acknowledgements This thesis is devoted to my beloved grandmother who was called to heaven on 2nd October 2004. Two months after her death, I swore to her that I would become a zoological doctor when I dreamed about her. Now is the time to fulfil the pledge. No matter what kinds of difficulty and patience I had suffered from, I never gave up owing to the pledge. I eternally bless her. I am here to express my greatest gratitude to Bornean civets. Without their existence, I would never have gotten into the wonderful and glorious rainforests. Their intriguing behaviours always hampered my sleep, yet they gave me happiness. I thank the Sabah Biodiversity Centre, Danum Valley Management Committee, and Sabah Wildlife Department for issuing and renewing my research permits. I am grateful for the support from Dr. Waidi Sinun, Mr. Jikos Gidiman, Dr. Yap Sau Wai, and Ms. Rose John Kidi of Yayasan Sabah, and Datuk Dr. Glen Reynolds of The British Royal Society. I sincerely thank my invaluable friends, Mr. Bapa Mike Bernadus Bala Ola, Mr. Adrian Kalorus, Mr. Alexander Karolus, Ms. Kakak Ica, Mrs. Arnold James (Noy), Azlin Bin Sailim (Asi), Jamiluddin Jami (Unding), Ruzmeel Mastor (Kon), Awen, Amat, Deddy, Fadil, Harry, 1 Jamil, Julian, Kikiy, Nel, Kitung, Tolot, Tamby, Remmy, Zinin, Joulu, Phillip, and Jonny of SERRAP, Anita, Amy, Fiffy, Richeal, Girl, Jamson, Siah, Nazri kecil, Nazri besar, Julie, Joe, Dot, Fazilah, Aziz, Una, Abang Walter, Lizuan, Raymond, Stef, Udin, Salimah, Hanimah, Bapa Karim, Pakcik Rani, Momo, Hamza, Marudin, Boy, Pakcik Tarman, Adam, Mandur, Abang Yus, Epha, Napin, Jaipin, Mandor, Apik, Sabidy, all staffs, and researchers (Graham, Mile Senior, Wendy, Norman, James, Sarah, Maria, Eli, Michael, Laini, and Alys) at Danum Valley Field Centre for making my life in Danum unforgettable and delightful. I am grateful to all BORA staffs, Datuk Dr. Junaidi Payne, Mr. Rashid Saburi, Mr. Soffian Abu Bakar, Mrs. Jumrafiha Abd. Sukor, Ms. Penny Gardner, all the members of Wildlife Department Sabah based in Tabin Wild Reserve and their families, and all the staffs of Tabin Wildlife Resort for their sincere assistance in Tabin. I am indebted to my research assistants, Mr. Fazlin, Mr. Mady and Mr. Logan Hamilton for their great assistance. Without their cooperation, I could not complete my work. My sincere thanks go to veterinaries Dr. Zainal Zahari Zainuddin in Tabin Wildlife Reserve and Dr. Tan L. Huat in Inanam for their assistance with anaesthesia in this study. I am grateful to Mr. Quentin Phillipps for the identification of fig species. I thank Dr. Joan Teresa Pereira and Ms. Rebecca Chong in Sabah Forestry Department for helping me with identification of plants. Special thanks go to all residences in Kg. Tampenau who brought 1 my minds back to childhood. I thank Datuk Clement Jaikul, his family and Ms. Anny who always took care of me when I stayed in Kota Kinabalu. I wish to express many thanks to my supervisor Prof. Dr. Shiro Kohshima for his invaluable advices. I am deeply grateful to Assoc. Prof. Dr. Hideki Sugiura for his sincere readings and helpful comments that greatly improved previous versions of the manuscript. I acknowledge my local counterpart Dr. Henry Bernard and Dr. Abdul Hamid Ahmad for their considerable assistance and support for this work. I am grateful to Dr. Thilahgavani Nagappan and Prof. Dr. Charles S. Vairappan for their collaboration in HPLC analyses. I gratefully acknowledge Prof. Drs. Genichi Idani, Tetsuro Matsuzawa, Assoc. Prof. Drs. Michio Nakamura, Goro Hanya, and all members of Wildlife Research Center of Kyoto University for their great advice and suggestions based on their field experiences. This research would only be possible with a lot of discussions, assistants, supports and encouragements from them. Special thanks belong to Dr. Yoshihiro Nakashima for giving me advice on civets. I am grateful to Drs. Hisashi Matsubayashi, Hiromitsu Samejima, Noko Kuze, Tomoko Kanamori, Ikki Matsuda, Yosuke Ohtani, Mr. Tomoyuki Tajima, Ms. Aoi Matsukawa, Ms. Renata Mendonça, and Mr. Shunsuke Kobayashi for their encouragements and supports in Sabah and in Japan. I would like to thank my parents and my elder brother for their understandings 1 and supports. Thanks for visiting Sabah and encouraging me. Gratitude is extended to Drs. Masao Kawai and Kunio Iwatsuki of Museum of Nature and Human Activities, Hyogo and Dr. Shigeki Yasuma who took me to Danum Valley in 2004 as a student of Borneo Jungle School when I was a high school student. During this school, I found a feeding common palm civet in canopy. This experiment became the preface of my interest in civets. Last but not least, thank you for all creatures living in the rainforests of Borneo. No matter what hardships I faced, I never surrendered my research because their appearance always brought me happiness and encouragement. I sincerely hope my study works as a trigger for letting people all over the world have interest in the Bornean rainforests and conservation awareness. This work was supported by the Sasagawa Scientific Research Grant from the Japan Science Society, International Training Program of HOPE, Science Core-to-Core Program, and Grants-in-Aid for Scientific Research to MN (#25-597) from The Japan Society for the Promotion of Science. 1 Table of contents Abstract ................................................................................................................................ 10 Chapter 1. General introduction .............................................................................................. 4 Chapter 2. General methods ................................................................................................... 11 2.1 STUDY SITE & STUDY PERIOD ............................................................................ 11 2.2 STUDY SPECIES