Sex-Specific Habitat Use and Responses to Fragmentation in an Endemic Chameleon Fauna
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Virginia Commonwealth University VCU Scholars Compass Theses and Dissertations Graduate School 2012 Sex-specific Habitat Use and Responses ot Fragmentation in an Endemic Chameleon Fauna Philip Shirk Virginia Commonwealth University Follow this and additional works at: https://scholarscompass.vcu.edu/etd Part of the Biology Commons © The Author Downloaded from https://scholarscompass.vcu.edu/etd/390 This Thesis is brought to you for free and open access by the Graduate School at VCU Scholars Compass. It has been accepted for inclusion in Theses and Dissertations by an authorized administrator of VCU Scholars Compass. For more information, please contact [email protected]. The College of Humanities & Sciences Virginia Commonwealth University This page certifies that the thesis prepared by Philip L Shirk entitled ―SEX-SPECIFIC HABITAT USE AND RESPONSES TO FRAGMENTATION IN AN ENDEMIC CHAMELEON FAUNA‖ has been approved by his committee as satisfactory completion of the thesis requirement for the degree of Master of Science in Biology. James Vonesh, Ph. D., Professor, Department of Biology, College of Humanities and Sciences Leslie Bulluck, Ph. D., Assistant Professor, Department of Biology, College of Humanities and Sciences David Patrick, Ph. D., Assistant Professor, Division of Forestry, Natural Resources, and Recreation, Paul Smith‘s College, Paul Smiths, NY Bryan Watts, Ph. D., Research Professor, Department of Biology, The College of William & Mary, Williamsburg, VA Donald R. Young, Ph. D., Chair of the Department of Biology, College of Humanities and Sciences Jim Coleman, Ph. D., Dean of the College of Humanities and Sciences F. Douglas Boudinot, Ph. D., Dean of the Graduate School 25 July, 2012 © Philip Shirk 2012 All Rights Reserved 2 SEX-SPECIFIC HABITAT USE AND RESPONSES TO FRAGMENTATION IN AN ENDEMIC CHAMELEON FAUNA A thesis submitted in partial fulfillment of the requirements for the degree of Master of Science at Virginia Commonwealth University. by PHILIP L SHIRK Bachelor of Arts B.A., Eastern Mennonite University, 2007 Major Professor: JAMES VONESH, PH.D. Professor, Department of Biology Virginia Commonwealth University Richmond, Virginia July, 2012 Acknowledgments I am thankful to many people for their contributions to my successful completion of my Master‘s degree, including: my advisor, Dr. James Vonesh, for his enthusiastic support and timely words of encouragement; Vonesh lab members, including Johanna Kraus, Chris Asquith, Zac Costa, Rachel Komosinski, and Julie Charbonnier for all of their support and shared experiences; Kim Howell, Carrie Seltzer, Nobby Cordeiro, Godfrey, Hunter, Aisha, Jeremy, Mwela, and all the staff of the Amani Nature Reserve, without whom my field work would surely have suffered; Jeff Wing and the VCU NSO for their assistance in applying for funding; VCU, Fulbright (PLS), The National Geographic Society (c154-08 - JRV, DAP, KMH, EAH), and The Explorer‘s Club Washington Group (PLS) for financial support; VCU IACUC (AD20237), COSTECH (2010 –226-NA-2010- 50), and TAWIRI for research permits and permissions; and most of all, my family. ii Table of Contents Page Acknowledgements ............................................................................................................. ii Table of Contents ............................................................................................................... iii List of Tables ......................................................................................................................v List of Figures .................................................................................................................... vi Abstract………. ................................................................................................................ vii Chapter 1. Female-biased sex ratios in the Usambara three-horned chameleon, real or apparent? .......................................................................................................................1 Abstract ....................................................................................................................2 Introduction ..............................................................................................................4 Methods....................................................................................................................6 Results ....................................................................................................................12 Discussion ..............................................................................................................17 Acknowledgements ................................................................................................22 Literature Cited ......................................................................................................23 Tables and Figures .................................................................................................29 iii Table of Contents (continued) Chapter 2. Chameleon community and population responses to habitat fragmentation in a tropical biodiversity hotspot .......................................39 Abstract ..................................................................................................................40 Introduction ............................................................................................................41 Methods..................................................................................................................46 Results ....................................................................................................................52 Discussion ..............................................................................................................55 Acknowledgements ................................................................................................60 Literature Cited ......................................................................................................61 Literature Cited 2 ...................................................................................................72 Tables and Figures .................................................................................................75 Vita .....................................................................................................................................85 iv List of Tables Page Ch 1. Female-biased sex ratios in the Usambara three-horned chameleon, real or apparent? Table 1.1: Observed adult and juvenile sex ratios .............................................................29 Table 1.2: Trioceros deremensis density estimates ..........................................................30 Table 1.3: Summary of survival estimates .........................................................................31 Table 1.4: Population projection model .............................................................................32 Ch 2. Chameleon community and population responses to habitat fragmentation in a tropical biodiversity hotspot Table 2.1: Coefficient values for PCA components. .........................................................75 Table 2.2: Comparison of Distance density models ..........................................................76 Table 2.3: Coefficient values of significant predictors of chameleon densities ................77 v List of Figures Page Ch 1. Female-biased sex ratios in the Usambara three-horned chameleon, real or apparent? Figure captions ...................................................................................................................33 Figure 1.1: Radio-transmitter attachment method .............................................................35 Figure 1.2: Seasonal histograms of T. deremensis size distributions ................................36 Figure 1.3: Size-dependent sex ratios ................................................................................37 Figure 1.4: Seasonal roost heights and proportion of time spent in canopy ......................38 Ch 2. Chameleon community and population responses to habitat fragmentation in a tropical biodiversity hotspot Figure captions ...................................................................................................................78 Figure 2.1: Map of forest fragments included in surveys. .................................................80 Figure 2.2: Observed and predicted counts of Rh. temporalis ...........................................81 Figure 2.3: Observed and predicted counts of T. deremensis ............................................82 Figure 2.4: Observed and predicted counts of Kinyongia spp. ..........................................83 Figure 2.5: Estimated and predicted chameleon species richness .....................................84 vi Abstract SEX-SPECIFIC HABITAT USE AND RESPONSES TO FRAGMENTATION IN AN ENDEMIC CHAMELEON FAUNA By Philip Shirk, B.A. A thesis submitted in partial fulfillment of the requirements for the degree of Master of Science in Biology at Virginia Commonwealth University. Virginia Commonwealth University, 2010 Director: James Vonesh, Ph.D., Professor, Department of Biology Chameleons are an understudied taxon facing many threats, including collection for the international pet trade and habitat loss and fragmentation. A recent field study reports a highly female-biased sex ratio in the Eastern Arc Endemic Usambara three horned chameleon, Trioceros deremensis, a large, sexually dimorphic