ECOLOGICAL INTERACTIONS OF ANOLIS CRISTATELLUS AND ANOLIS KRUGI IN TWO SECONDARY TROPICAL KARST FORESTS AT THE NORTHERN KARST BELT OF PUERTO RICO: OCCUPANCY ESTIMATES AND DEGREE OF OMNIVORY/FRUGIVORY By Sondra I. Vega-Castillo A thesis submitted to the Biology Intercampus Graduate Program DEPARTMENT OF BIOLOGY FACULTY OF NATURAL SCIENCES UNIVERSITY OF PUERTO RICO RIO PIEDRAS CAMPUS In partial fulfillment of the requirements for the degree of DOCTOR IN PHILOSOPHY May 2014 Río Piedras, Puerto Rico ©Sondra I. Vega Castillo All rights reserved i TABLE OF CONTENTS LIST OF TABLES .............................................................................................................................. v LIST OF FIGURES ............................................................................................................................ vii LIST OF APPENDICES .................................................................................................................... xii ABSTRACT ...................................................................................................................................... xiii BIOGRAPHY .................................................................................................................................... xv ACKNOWLEDGEMENTS ................................................................................................................ 3 CHAPTER I ........................................................................................................................................ 5 INTRODUCTION, OBJECTIVES AND OVERVIEW OF CHAPTERS .......................................... 5 Introduction ..................................................................................................................................... 6 Objective of the Thesis .................................................................................................................... 8 Overview of Chapters ..................................................................................................................... 9 Chapter II .......................................................................................................................................... 10 INFLUENCE OF HABITAT STRUCTURE AND QUALITY ON OCCUPANCY AND ABUNDANCE OF TWO ANOLES ECOMORPHS, ANOLIS CRISTATELLUS AND ANOLIS KRUGI, IN SECONDARY KARST FORESTS OF NORTHERN PUERTO RICO. ...................... 10 Abstract ......................................................................................................................................... 11 Introduction ................................................................................................................................... 12 Methods ......................................................................................................................................... 14 Study areas ................................................................................................................................ 14 Focal species ............................................................................................................................. 15 Demographic parameters and habitat characterization ........................................................... 15 Statistical analysis ..................................................................................................................... 17 Results ........................................................................................................................................... 20 Habitat characterization ........................................................................................................... 20 Prey availability ........................................................................................................................ 21 Occupancy and abundance ....................................................................................................... 21 Discussion ..................................................................................................................................... 24 TABLES ........................................................................................................................................ 30 FIGURES ...................................................................................................................................... 45 APPENDICES ............................................................................................................................... 58 ii CHAPTER III .................................................................................................................................... 63 OMNIVORY AND TROPHIC POSITION OF ANOLIS CRISTATELLUS AND ANOLIS KRUGI AT TWO SECONDARY KARST FOREST ON NORTHERN PUERTO RICO ............................ 63 Abstract ......................................................................................................................................... 64 Introduction ................................................................................................................................... 65 Methods ......................................................................................................................................... 68 Study areas ................................................................................................................................ 68 Samples collection ..................................................................................................................... 68 Stable Isotopes Analysis ............................................................................................................ 69 Food resources availability ....................................................................................................... 70 Statistical analysis ..................................................................................................................... 71 Results ........................................................................................................................................... 73 Food resources availability ....................................................................................................... 74 Discussion ..................................................................................................................................... 76 TABLES ........................................................................................................................................ 80 FIGURES ...................................................................................................................................... 93 CHAPTER IV ................................................................................................................................. 110 EFFECTS OF SEASONAL CHANGES IN FOOD AVAILABILITY ON THE DIET OF ANOLIS CRISTATELLUSAND A. KRUGI AT TWO KARST FORESTS AT NORTHERN PUERTO RICO ......................................................................................................................................................... 110 Abstract ....................................................................................................................................... 111 Introduction ................................................................................................................................. 112 Methods ....................................................................................................................................... 115 Study areas .............................................................................................................................. 115 Samples collection ................................................................................................................... 115 Stable Isotopes Analysis .......................................................................................................... 116 Food resources availability ..................................................................................................... 118 Statistical Analyses .................................................................................................................. 119 Results ......................................................................................................................................... 120 Food resources availability ..................................................................................................... 122 Discussion ................................................................................................................................... 124 TABLES ...................................................................................................................................... 129 FIGURES .................................................................................................................................... 136 iii CHAPTER V ................................................................................................................................... 175 CONCLUSION ............................................................................................................................... 175 Conclusion................................................................................................................................... 176 LITERATURE CITED ..................................................................................................................