Western University Scholarship@Western Electronic Thesis and Dissertation Repository 2-27-2017 12:00 AM The Effects of Sex, Energy, and Environmental Conditions on the Movement Ecology of Migratory Bats Kristin A. Jonasson The University of Western Ontario Supervisor Dr. Christopher Guglielmo The University of Western Ontario Graduate Program in Biology A thesis submitted in partial fulfillment of the equirr ements for the degree in Doctor of Philosophy © Kristin A. Jonasson 2017 Follow this and additional works at: https://ir.lib.uwo.ca/etd Part of the Biology Commons, Comparative and Evolutionary Physiology Commons, and the Other Ecology and Evolutionary Biology Commons Recommended Citation Jonasson, Kristin A., "The Effects of Sex, Energy, and Environmental Conditions on the Movement Ecology of Migratory Bats" (2017). Electronic Thesis and Dissertation Repository. 4411. https://ir.lib.uwo.ca/etd/4411 This Dissertation/Thesis is brought to you for free and open access by Scholarship@Western. It has been accepted for inclusion in Electronic Thesis and Dissertation Repository by an authorized administrator of Scholarship@Western. For more information, please contact [email protected]. iii ABSTRACT Lack of knowledge about the behaviour of migratory species during the migratory period is a major barrier to conservation efforts. In this thesis, I focus primarily on differences between the sexes of the bat Lasionycteris noctivagans, during spring migration. Females are pregnant during spring migration and this overlap between migration and reproduction may affect the time and energy management of females as compared to males. In Chapter 2, I examine spring migration phenology of bats at a stopover site. Females arrived earlier than males, likely to give their pups a long growing season. Fat stores appeared to reflect a strategy to provision for upcoming lactation demands. In Chapter 3, I explore stopover behaviour and I show that despite the use of torpor to minimize roosting energy expenditure, cold weather extends stopover duration. There was no sex difference in the length of time spent at stopover. By regressing the time of night bats were captured against their fat and lean mass I demonstrate that bats have greater fat and lean masses closer to dawn, and therefore are likely using stopover periods to refuel. In Chapter 4, I compare sex and seasonal differences in daytime torpor use at stopover. I found that in spring bats used torpor for fewer hours than in autumn, even after accounting for the effect of ambient temperature. Further, females used torpor for fewer hours than males. I propose that these seasonal differences are due to lower prey abundance and predictability in spring; sex differences may be attributable to a higher foraging intensity by females compared to males. Finally, in Chapter 5, I use a radio- telemetry array in southwestern Ontario, Canada to track the spring and autumn long distance migratory movements of L. noctivagans, Lasiurus borealis, and Lasiurus cinereus. No migration corridors were identified in either season. Estimated migration speeds indicate that multiday stopovers are also used in the autumn. These studies combined show that sex affects the spring migration time and energy management of bats. Bat migration research is still in its formative stages and my studies provide new information on bat migration in North America. Keywords: automated radio-telemetry, body composition, Chiroptera, departure iv decisions, energy balance, fat stores, flight behaviour, flight speed, heterothermy, Lasionycteris noctivagans, Lasiurus borealis, Lasiurus cinereus, leading lines, phenology, protogeny, migration, migratory corridor, migratory routes, migratory strategies, refueling, stopover, sex differences, tailwind assistance, thermoregulation, torpor, torpor-assisted migration, vernal migration, wind energy v STATEMENT OF CO-AUTHORSHIP A version of Chapter 2 “Sex differences in spring migration timing and body composition of silvered-haired bats (Lasionycteris noctivagans)” was published in the Journal of Mammalogy with Christopher Guglielmo as co-author. Chapter 3 “Evidence for spring stopover refueling in migrating silver-haired bats (Lasionycteris noctivagans)” will be submitted to the Functional Ecology with Christopher Guglielmo as co-author. Chapter 4 “Cold Breaks: Seasonal and sex differences in daily torpor use by migrating silver-haired bats (Lasionycteris noctivagans)” will be submitted to Physiological and Biochemical Zoology with Christopher Guglielmo as co-author. Chapter 5 “Spring and autumn migratory movements of North American Tree-bats (L. noctivagans, L. borealis and L. cinereus) using the MOTUS wildlife tracking system” will be submitted to Animal Behaviour with Christopher Guglielmo as co-author. Chapters 2-5 are co-authored by Christopher Guglielmo. Dr. Guglielmo was involved in study design, provided equipment, assisted with interpreting the data and made editorial comments. vi ACKNOWLEDGEMENTS I dedicate this thesis to my parents Tom & Joann Jonasson – for their encouragement to always follow my passions. They have been there for me during the ups and downs of the entire PhD process and I could not be more grateful. I could not be more fortunate to have Chris as my supervisor and mentor. I am grateful for the support and advice he provided throughout this research. When my receivers wouldn’t work, my transmitters were broken, and my personal life was unsteady, Chris was there with an encouraging and problem-solving attitude. Chris is enthusiastic, not afraid to take risks and tackle big projects; he shared this energy and my research is richer for it. I’m a better scientist for having worked with Chris. Dr. Jim Staples and Dr. Brock Fenton provided outstanding counsel and guidance as members of my advisory committee. I am grateful to Dr. Brock Fenton, Dr. Scott MacDougal-Shackleton and Dr. Brent Sinclair for providing me with a challenging and, dare I say fun, comprehensive examination. I am particularly thankful to Dr. Liam McGuire for approaching me at NASBR, and asking “what’s next?”. I wouldn’t have found my place in this amazing lab without that conversation. I count myself very fortunate to have worked alongside all of the members of the Gug lab – Dylan Baloun, Dr. Alice Boyle, Morag Dick, Jessica Deakin, Alex Gerson, Yanji Ma, Dr. Ivan Maggini, Liam McGuire, Brendan McCabe, Dr. Greg Mitchel, Dr. Silke Nibel, Laura Rooney, and Caitlin Vandermeer. They provided an intellectually stimulating environment and countless feedback on presentations and earlier drafts. I’m further grateful to all the members of the AFAR over the years, they have been like an extended lab group, to share graduate student experience with. For providing emotional support when writing this thesis seemed daunting, I am indebted to Sam Chippin, Krispin Davies, Morag Dick, Danielle Griffith, and Thomas Lilley. vii For assistance with field work, I thank my dear friends Morag Dick, Melissa Donnelly, Erin Fraser, Lauren Grant, Kaleigh Norquay Alex McMillian, Jordi Segers and Hillary Williamson for their comradery and unflagging optimism. I am particularly grateful to Kaleigh Norquay and Jordi Segers, whose positive, engaging attitudes kept me afloat through difficult times. It isn’t easy to work all through the night, particularly when the bats are slow, but they did it with aplomb. Stuart MacKenzie and Greg Mitchell were invaluable in handling the logistics of deploying and maintaining the MOTUS telemetry array, as were the array technicians David Bell, Daniel Giesbrecht, and Adam Timph. The staff and volunteers at the Long Point Bird Observatory and the Bruce Peninsula Bird Observatory were most gracious in sharing both their nets and their living quarters with our nocturnal crew. These stations have been my home away from home. I thank L. Adams, M. Siekierski, A. Jarecka, R. and N. Steinacher for access to private property, and for their encouragement and interest in my research. viii TABLE OF CONTENTS Certificate of Examination ................................................................................................. ii Abstract .............................................................................................................................. ii Statement of Co-authorship ................................................................................................iv Acknowledgements .............................................................................................................. v Table of Contents ............................................................................................................. vii List of Tables ..................................................................................................................... x List of Figures ....................................................................................................................xi List of Appendices ........................................................................................................... xv CHAPTER 1 ....................................................................................................................... 1 INTRODUCTION .............................................................................................................. 1 1.1 Why migrate? .......................................................................................................... 1 1.2 Sex and migration ..................................................................................................