ECOLOGICAL AND PHYSIOLOGICAL EFFECTS OF ENVIRONMENTAL STRESSORS ACROSS LIFE-STAGES IN AMPHIBIANS by KACEY L. DANANAY Submitted in partial fulfillment of requirements For the degree of Doctor of Philosophy Advisor: Dr. Michael F. Benard Department of Biology CASE WESTERN RESERVE UNIVERSITY August 2018 CASE WESTERN RESERVE UNIVERSITY SCHOOL OF GRADUATE STUDIES We hereby approve the thesis/dissertation of Kacey L. Dananay candidate for the Doctor of Philosophy degree*. Committee Chair: Karen Abbott Committee Member: Michael Benard Committee Member: Jean Burns Committee Member: Mandi Schook Committee Member: Mark Willis Date of Defense: March 19th, 2018 *We also certify that written approval has been obtained for any proprietary material contained therein. ii Copyright © by Kacey L. Dananay All rights reserved iii DEDICATION To my family and friends who have supported me through this journey iv TABLE OF CONTENTS List of Tables ............................................................................................................viii List of Figures ...........................................................................................................ix Acknowledgements ..................................................................................................x Abstract .....................................................................................................................1 Chapter 1: Introduction ..........................................................................................3 Environmental stressors .............................................................................................3 Road salt runoff..........................................................................................................3 Artificial Light At Night (ALAN) ............................................................................4 Research program and goals ......................................................................................5 Chapter 2: Legacy of Road Salt: Apparent Positive Larval Effects Counteracted by Negative Post Metamorphic Effects in Wood Frogs .............................................7 Abstract ......................................................................................................................7 Introduction ................................................................................................................8 Materials and Methods ...............................................................................................11 Field Survey: ........................................................................................................11 Statistical Analyses: .........................................................................................12 Experimental Venue: ............................................................................................13 Experiment 1: Salt concentration: .........................................................................14 Statistical Analyses ..........................................................................................16 Experiment 2: Carry-over effects: ........................................................................16 Statistical Analyses ..........................................................................................18 Results ........................................................................................................................18 v Field Survey: .........................................................................................................18 Experiment 1: Salt concentration ..........................................................................19 Experiment 2: Carry-over effects ..........................................................................21 Discussion ..................................................................................................................22 Tables .........................................................................................................................27 Figures........................................................................................................................29 Chapter 3: Artificial Light at Night decreases metamorphic duration and increases juvenile growth in a widespread amphibian .........................................................35 Abstract ......................................................................................................................35 Introduction ................................................................................................................36 Materials and Methods ...............................................................................................38 Study System ........................................................................................................38 Experiment 1: Testing for direct and indirect effect of ALAN in larvae ..............38 Statistical Analyses ..........................................................................................42 Experiment 2: Prior and subsequent effects of light on post-metamorphic toads .................................................................................................................43 Statistical Analyses ..........................................................................................45 Results ........................................................................................................................46 Experiment 1: Testing for direct and indirect effect of ALAN in larvae ..............46 Experiment 2: Prior and subsequent effects of light on post-metamorphic toads .................................................................................................................47 Discussion ..................................................................................................................47 Figures .......................................................................................................................51 Supplementary Tables ................................................................................................53 Supplementary Figures .............................................................................................56 vi Chapter 4: Artificial Light At Night and Predator-Prey Dynamics: consumptive and non-consumptive effects of predators are not reflected in corticosterone of American toads ..........................................................................................................................60 Abstract ......................................................................................................................60 Introduction ................................................................................................................61 Materials and Methods ...............................................................................................64 Experiment 1: Physiological effects of ALAN and predator presence on larval American toads ................................................................................................64 Statistical Analysis ...........................................................................................67 Experiment 2: Effects of larval stage and juvenile stage ALAN on juvenile Toads ................................................................................................................68 Statistical Analysis ...........................................................................................69 Hormone extraction and corticosterone radioimmunoassay (RIA) procedures ....70 Results ........................................................................................................................71 Experiment 1: Physiological effects of ALAN and predator presence on larval American toads ................................................................................................71 Experiment 2: Effects of larval stage and juvenile stage ALAN on juvenile Toads ................................................................................................................72 Discussion ..................................................................................................................73 Tables .........................................................................................................................79 Figures........................................................................................................................81 Chapter 5: Conclusions: ..........................................................................................83 Advancements of my research program ...............................................................83 Future directions ...................................................................................................85 Bibliography: ............................................................................................................88 vii LIST OF TABLES Chapter 2: Table 2.1: .............................................................................................................27 Chapter 3: Table S3.1.............................................................................................................53 Table S3.2.............................................................................................................54 Table S3.3.............................................................................................................55 Table S3.4.............................................................................................................55