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Diamondback Terrapin, Malaclemys Terrapin, Nesting and Overwintering Ecology

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Diamondback Terrapin, Malaclemys Terrapin, Nesting and Overwintering Ecology Diamondback Terrapin, Malaclemys terrapin, Nesting and Overwintering Ecology A thesis presented to the faculty of the College of Arts and Sciences of Ohio University In partial fulfillment of the requirements for the degree Master of Science Leah J. Graham June 2009 © 2009 Leah J. Graham. All Rights Reserved. 2 This thesis titled Diamondback Terrapin, Malaclemys terrapin, Nesting and Overwintering Ecology by LEAH J. GRAHAM has been approved for the Program of Environmental Studies and the College of Arts and Sciences by Willem M. Roosenburg Associate Professor of Biological Sciences Benjamin M. Ogles Dean, College of Arts and Sciences 3 ABSTRACT GRAHAM, LEAH J., M.S., June 2009, Environmental Studies Diamondback Terrapin, Malaclemys terrapin, Nesting and Overwintering Ecology (69 pp.) Director of Thesis: Willem M. Roosenburg Poplar Island Environmental Restoration Project is a unique solution for the dredge material placement and restoring decreasing habitat in the Chesapeake Bay. Since 2002, a long-term terrapin monitoring program has been documenting diamondback terrapin, Malaclemys terrapin habitat use. Northern diamondback terrapins, hatchlings may either emerge from their nest in the fall and seek other overwintering hibernacula, or remain inside their natal nest to emerge the following spring, known as delayed emergence. Results from the 2007-08 nesting season found that compaction and the presence of ice nucleating agents (as a measure of crystallization temperature) affected nest emergence timing in hatchlings. Fall emerged nests had lower bulk density (less compacted) and had a higher potency of ice nucleating agents compared to spring emerging nests. With proper management, areas such as Poplar Island may become areas of concentration for terrapins and thus provide a source population for the terrapin recovery throughout the Bay. Approved: _____________________________________________________________ Willem M. Roosenburg Associate Professor of Biological Sciences 4 ACKNOWLEDGMENTS This study could not have been completed without the support and guidance of many people. First, I’d like to express sincere gratitude to Dr. Willem Roosenburg for his encouragement, confidence, time, expertise, advice, and patience seeing the completion of this study and the growth of myself as a researcher. I am indebted to Willem since the first day I knocked on his office door and am grateful for the time, joys, and insights on terrapins he has shared with me. I am grateful to my committee members Dr. Jared DeForest and Dr. Matthew White for their knowledge, expertise, comments, and guidance throughout this project and encouragement to enter OU’s MSES program. The research could not have been completed without the support of the Maryland/DC Chapter Nature Conservancy Biodiversity Conservation Research Fund. I am grateful to USACE, MES, and MPA for support of terrapin research on Poplar Island. I would like to thank Kate Kelley for her comments, support, many excellent meals and times at Cremona, MD. I would like to thank those who helped collect data from 2002- 2007: Kathleen Temple-Miller, Ashley Smith, Dana Spontak, Sean Sullivan, Eva Matthews, Mark Ratchford , Alex Fotis , Ryan Oltjen, Tina Shalek, Josh Erhart, Hannah Goldman, Marie Braasch, Peter Markos, Phil Allman, Brad Fruh, Emily Vlahovich, Joe Clark,Tom Radzio, Jaclyn Smolinski, Lindsey Koch. In particular I’m grateful to 2007- 08 field assistants Alanna Silva form the University of Belem, Brazil and, Natalie Boydston, Scott Clark, and Brooks Kohli from Ohio University. I’d like to sincerely thank 2007-08 field assistant Melanie Heckman and 2008-09 lab assistant Ashley Zibert who aided in collecting data. 5 I am grateful for the friendship, support and encouragement from Ohio University Office of Sustainability friends (Sonia Marcus, Erin Sykes, Molly Shea, Leah Crowe, Catherine Tulley, Jessica Patterson, Amy Nordrum, and Sarah DeWitt) over the past two years. I appreciate the Roosenburg lab members (Kathleen Temple-Miller, Chris Howey, Nate Ruhl, Nick Smeenk, Steve Ecrement, Holly De’Angelis and Abby Crosby) for their comments and ideas. I would like to express my gratitude to my parents Jon and Martha Graham for their financial and emotional support. Finally a special thanks to my parents, brother, Adam Graham, and Jamie DeMonte for believing in me. Thank you for always being there. 6 TABLE OF CONTENTS Page Abstract............................................................................................................................... 3 Acknowledgments............................................................................................................... 4 List of Tables ...................................................................................................................... 8 List of Figures..................................................................................................................... 9 Chapter 1: Terrapin Nesting Ecology ............................................................................... 10 Materials and Methods.................................................................................................. 12 Study Site: Poplar Island Environmental Restoration Project .................................. 12 Study Species: Diamondback terrapin, Malaclemys terrapin ................................... 14 Poplar Island Field Methods ..................................................................................... 19 Statistical Analysis.................................................................................................... 21 Results........................................................................................................................... 21 Discussion..................................................................................................................... 31 Chapter 2: Terrapin Overwintering Ecology .................................................................... 36 Emergence Timing in Hatchlings ................................................................................. 38 Physiology of Overwintering and Soil.......................................................................... 40 Materials and Methods.................................................................................................. 42 Study Species: Diamondback Terrapin, Malaclemys terrapin.................................. 42 Study Site: Poplar Island Environmental Restoration Project .................................. 43 Soil Sampling............................................................................................................ 44 Nest Soil Analysis..................................................................................................... 45 7 Statistical Analysis.................................................................................................... 46 Results........................................................................................................................... 47 Discussion..................................................................................................................... 58 References......................................................................................................................... 64 8 LIST OF TABLES Page Table 1: PIERP terrapin nest fate 2002-2007 .................................................................26 Table 2: Nest fate and overwintering percentage 2006-2006 .........................................27 9 LIST OF FIGURES Page Figure 1: Chesapeake Bay ..............................................................................................17 Figure 2: PIERP terrapin nesting habitat ........................................................................18 Figure 3: Terrapin nest locations 2002-2007..................................................................24 Figure 4: Proportion and number of nests in major PIERP nesting areas ......................25 Figure 5: Spring and fall hatchling lipid levels 2005......................................................28 Figure 6: Fall and spring within nest survivorship 2004-2007.......................................29 Figure 7: Fall and spring emerging nests lay date 2005-2007........................................30 Figure 8: 2007 Fall and spring emerging nests along the notch and Cell 5....................50 Figure 9: 2007 Fall and spring texture (percent of sand)................................................51 Figure 10: 2007 Fall and spring texture (percent of silt and clay)..................................52 Figure 11: 2007 Fall and spring organic matter..............................................................53 Figure 12: 2007 Fall and spring bulk density .................................................................54 Figure 13: 2007 Fall and spring bulk density and emergence timing.............................55 Figure 14: 2007 Fall and spring inorganic and organic INAs ........................................56 Figure 15: Fall and spring emerging nests lay date 2005-2007.....................................57 10 CHAPTER 1: TERRAPIN NESTING ECOLOGY Increases in human populations result in; habitat destruction, habitat infrastructure deterioration, introduced species, subsidized predators, and overexploitation of natural resources for food and pets (Klemens, 2000). Estuarine ecosystems continue to be threatened as human population growth increases in coastal areas and development increases habitat loss,
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