ABSTRACT OF DISSERTATION Luke Elden Dodd The Graduate School University of Kentucky 2010 FOREST DISTURBANCE AFFECTS INSECT PREY AND THE ACTIVITY OF BATS IN DECIDUOUS FORESTS ____________________________________ ABSTRACT OF DISSERTATION _____________________________________ A dissertation submitted in partial fulfillment of the requirements for the degree of Doctor of Philosophy in the College of Agriculture at the University of Kentucky By Luke Elden Dodd Lexington, Kentucky Director: Dr. Lynne K. Rieske-Kinney, Professor of Entomology Lexington, Kentucky 2010 Copyright © Luke Elden Dodd 2010 ABSTRACT OF DISSERTATION FOREST DISTURBANCE AFFECTS INSECT PREY AND THE ACTIVITY OF BATS IN DECIDUOUS FORESTS The use of forest habitats by insectivorous bats and their prey is poorly understood. Further, while the linkage between insects and vegetation is recognized as a foundation for trophic interactions, the mechanisms that govern insect populations are still debated. I investigated the interrelationships between forest disturbance, the insect prey base, and bats in eastern North America. I assessed predator and prey in Central Appalachia across a gradient of forest disturbance (Chapter Two). I conducted acoustic surveys of bat echolocation concurrent with insect surveys. Bat activity and insect occurrence varied regionally, seasonally, and across the disturbance gradient. Bat activity was positively related with disturbance, whereas insects demonstrated a mixed response. While Lepidopteran occurrence was negatively related with disturbance, Dipteran occurrence was positively related with disturbance. Shifts in Coleopteran occurrence were not observed. Myotine bat activity was most correlated with sub-canopy vegetation, whereas lasiurine bat activity was more correlated with canopy-level vegetation, suggesting differences in foraging behavior. Lepidoptera were most correlated with variables describing understory vegetation, whereas Coleoptera and Diptera were more correlated with canopy-level vegetative structure, suggesting differences in host resource utilization. I assessed the food habits of bats captured in mist nets. Morphological identification of prey suggested consumption of insect taxa varies across bat species and, at least for the most commonly-captured species, Myotis septentrionalis, across the region (Chapter Three). Trophic connections were further delineated between M. septentrionalis and its prey by sequencing C OI fragments of insect prey obtained from fecal samples. Prey identities were inferred for C OI fragments using web-based searches (Chapter Four), as well as tree-building analyses (Chapter Five). Lepidoptera were detected most frequently in all prey identification procedures, though prey detection varied with procedure thus suggesting methodological bias. Prey species were identified using the Barcode of Life Database; the wingspan of prey consumed by M. septentrionalis was smaller than that reported for other sympatric species. My research demonstrates regional variation in bat activity, bat foraging, and prey occurrence across a gradient of forest disturbance. Conservation efforts should consider the importance of vegetation structure and plant species richness to sustain populations of both bats and their insect prey. KEYWORDS: foraging ecology, predator-prey interactions, food habits, forest succession, Appalachia _______________________ _______________________ FOREST DISTURBANCE AFFECTS INSECT PREY AND THE ACTIVITY OF BATS IN DECIDUOUS FORESTS By Luke Elden Dodd ________________________________ Director of Dissertation ________________________________ Director of Graduate Studies ________________________________ RULES FOR THE USE OF DISSERTATIONS Unpublished dissertations submitted for the Doctor’s degree and deposited in the University of Kentucky Library are as a rule open for inspection, but are to be used only with due regard to the rights of the authors. Bibliographical references may be noted, but quotations or summaries of part may be published only with the permission of the author, and with the usual scholarly acknowledgments. Extensive copying or publication of the dissertation in whole or in part also required the consent of the Dean of the Graduate School of the University of Kentucky. A library that borrows this dissertation for use by its patrons is expected to secure the signature of each user. Name Date DISSERTATION Luke Elden Dodd The Graduate School University of Kentucky 2010 FOREST DISTURBANCE AFFECTS INSECT PREY AND THE ACTIVITY OF BATS IN DECIDUOUS FORESTS _____________________________________ DISSERTATION _____________________________________ A dissertation submitted in partial fulfillment of the requirements for the degree of Doctor of Philosophy in the College of Agriculture at the University of Kentucky By Luke Elden Dodd Lexington, Kentucky Director: Dr. Lynne K. Rieske-Kinney, Professor of Entomology Lexington, Kentucky 2010 Copyright © Luke Elden Dodd 2010 ACKNOWLEDGMENTS This project would not have been possible without the gracious assistance and cooperation of a number of groups. The National Council for Air and Stream Improvement, Inc., provided primary funding for this project, as well as field assistance. The U.S. Forest Service provided invaluable assistance in the field. I would like to further thank the U.S. Forest Service, the state of Tennessee, and Plum Creek Timber Company who gave permission for this research to be conducted on their lands. Additional funding sources for my research included Bat Conservation International, McIntire-Stennis Funding, Sigma Xi, and the University of Kentucky Graduate School. Thank you to all these organizations and agencies for making my research possible. I would like to thank my graduate committee. Dr. Charles Fox and Dr. John Obrycki provided insight and critique regarding the design of this project. Dr. James Harwood was instrumental in my research and his involvement expanded my interests in molecular tools and applications. Dr. Lacki provided critical insight into study design and has continued to be strong mentor. I am particularly grateful to my advisor, Dr. Lynne Rieske-Kinney, whose guidance and academic support was invaluable to this student. I am truly in her debt and thank her for all she has taught me. I would also like to thank Dr. Rodney Cooper, Dr. Eric Britzke, and Dr. Eric Chapman, all of whom contributed to the development of my research. I am grateful for their aid, patience, and tutelage. I would like to thank all the technicians who made this project possible: Josh Adams, Melanie Antonik, Allison Barlows, Elizabeth Carlisle, Drew Chalkley, Spencer Gravitt, Jessica Rasmussen, Rebecca Smith, and Joe Wong. I would particularly like to iv thank both Tracy Culbertson and Matt “Reamer” Ware for jobs well done and all of their leadership and efforts in the field; this project would not have been possible without the efforts of both of them. I would finally like to thank those who provided moral support over the past four years. To my fellow lab mates, Josh Adkins, Melanie Antonik, Paul Ayayee, Dr. Michael Baker, Erin Barding, Josh Clark, Dr. Tom Coleman, Dr. Rodney Cooper, Dan Cox, Joe Johnson, Aerin Land, Rachael Mallis, and Heather Spaulding, I am grateful for your assistance and friendship. To my friends from Arkansas: the late-nighters from Tech and those from Hatfield, thank you for always being there. To all the other friends that I have made in Kentucky over the past few years: the beer club at Marikka’s, the D&D guys, and other grad students in the Entomology and Forestry Departments, thank you for the good times and keeping me sane. Finally, to my girlfriend Liz and my family: Mom, Ronda, Tonya, and my grandparents, thank you for your love and support! v TABLE OF CONTENTS Acknowledgements ............................................................................................................ iv List of tables ....................................................................................................................... ix List of figures ...................................................................................................................... x Chapter one: Introduction.................................................................................................... 1 Statement of issue ............................................................................................................ 1 Objectives and hypotheses............................................................................................... 2 Management implications ............................................................................................... 5 Chapter two: Bat activity and insect occurrence varies along a gradient of disturbance .... 7 Introduction ..................................................................................................................... 7 Methods ......................................................................................................................... 10 Study areas and disturbance ....................................................................................... 10 Bat activity ................................................................................................................. 11 Insect occurrence ....................................................................................................... 11 Vegetation assessment ..............................................................................................