Ecology of the Endemic Mearns's Squirrel (Tamiasciurus Mearnsi) in Baja California, Mexico
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Ecology of the Endemic Mearns's Squirrel (Tamiasciurus Mearnsi) in Baja California, Mexico Item Type text; Electronic Dissertation Authors Ramos-Lara, Nicolas Publisher The University of Arizona. Rights Copyright © is held by the author. Digital access to this material is made possible by the University Libraries, University of Arizona. Further transmission, reproduction or presentation (such as public display or performance) of protected items is prohibited except with permission of the author. Download date 02/10/2021 17:04:27 Link to Item http://hdl.handle.net/10150/228171 ECOLOGY OF THE ENDEMIC MEARNS’S SQUIRREL ( TAMIASCIURUS MEARNSI ) IN BAJA CALIFORNIA, MEXICO by Nicolas Ramos-Lara A Dissertation Submitted to the Faculty of the SCHOOL OF NATURAL RESOURCES AND THE ENVIRONMENT In Partial Fulfillment of the Requirements For the Degree of DOCTOR OF PHILOSOPHY WITH A MAJOR IN WILDLIFE AND FISHERIES SCIENCE In the Graduate College THE UNIVERSITY OF ARIZONA 2012 2 THE UNIVERSITY OF ARIZONA GRADUATE COLLEGE As members of the Dissertation Committee, we certify that we have read the dissertation prepared by Nicolas Ramos-Lara entitled: Ecology of the endemic Mearns’s squirrel ( Tamiasciurus mearnsi ) in Baja California, Mexico and recommend that it be accepted as fulfilling the dissertation requirement for the Degree of Doctor of Philosophy __________________________________________________ Date: 10 April 2012 John L. Koprowski __________________________________________________ Date: 10 April 2012 Judith L. Bronstein __________________________________________________ Date: 10 April 2012 R. William Mannan __________________________________________________ Date: 10 April 2012 William W. Shaw Final approval and acceptance of this dissertation is contingent upon the candidate’s submission of the final copies of the dissertation to the Graduate College. I hereby certify that I have read this dissertation prepared under my direction and recommend that it be accepted as fulfilling the dissertation requirement. __________________________________________________ Date: 10 April 2012 Dissertation Director: John L. Koprowski 3 STATEMENT BY AUTHOR This dissertation has been submitted in partial fulfillment of requirements for an advanced degree at the University of Arizona and is deposited in the University Library to be made available to borrowers under rules of the Library. Brief quotations from this dissertation are allowable without special permission, provided that accurate acknowledgment of source is made. Requests for permission for extended quotation from or reproduction of this manuscript in whole or in part may be granted by the head of the major department or the Dean of the Graduate College when in his or her judgment the proposed use of the material is in the interests of scholarship. In all other instances, however, permission must be obtained from the author. SIGNED: Nicolas Ramos-Lara 4 ACKNOWLEDGEMENTS I am indebted to my advisor John Koprowski for his advice, encouragement and support, and for giving me the opportunity to embark in this journey. I thank my committee members Judy Bronstein, Bill Mannan, and Bill Shaw for their guidance and for being part of this journey. I thank all the people in the squirrel lab for their help and friendship during all this time: Bret Pasch, Claire Zugmeyer, Debbie Buecher, Erin Posthumus, Geoff Palmer, Hsiang Ling Chen, Jonathan Derbridge, Kate Leonard, Margaret Rheude, Melissa Merrick, Nathan Gwinn, Nichole Cudworth, Rebecca Minor, Rosa Jessen, Sandy Doumas, Sarah Hale, Seafha Blount, Shari Ketcham, Tim Jessen, and Vicki Greer. I also thank Alberto Macias-Duarte and all the people who directly or indirectly contributed to this research. This research was possible thanks to the financial support provided by the Desert Southwest Cooperative Ecosystem Studies Unit, the Intermountain Region International Conservation Office (IMRICO) of the National Park Service, the Arizona Agricultural Experiment Station, T&E, Inc., the Consejo Nacional de Ciencia y Tecnología (CONACYT) of Mexico, and the Wallace Research Foundation. This research was conducted under permits from the University of Arizona Institutional Animal Care and Use Committee, Dirección Forestal y de la Fauna Parque Nacional Sierra de San Pedro Mártir, and Dirección General de Vida Silvestre. The Observatorio Astronómico Nacional of the Universidad Nacional Autónoma de México facilitated housing logistics. The Servicio Meteorológico Nacional provided temperature and precipitation data of the region. I thank William Shaw, R. William Mannan, Bret Pasch, Melissa Merrick, Nicole Tautfest, Chris Schvarcz, Claire Zugmeyer, and Geoff Palmer for their assistance in the field. I also thank Sam Drake for processing the satellite imagery of the Sierra de San Pedro Mártir. 5 DEDICATION This dissertation is dedicated to the loving memory of my mother, Ana María Lara-Meza ¡Gracias Madre! 6 TABLE OF CONTENTS LIST OF TABLES ...............................................................................................................7 LIST OF FIGURES ...........................................................................................................10 ABSTRACT .......................................................................................................................13 CHAPTER 1. INTRODUCTION ......................................................................................15 CHAPTER 2. PRESENT STUDY .....................................................................................21 REFERENCES ..................................................................................................................24 APPENDIX A. DEFORESTATION AND KNOWLEDGE GAPS THREATEN CONSERVATION OF THE ARBOREAL SQUIRRELS OF MEXICO .........................31 APPENDIX B. NEST-SITE CHARACTERISTICS OF THE MONTANE ENDEMIC MEARNS’S SQUIRREL ( TAMIASCIURUS MEARNSI ): AN OBLIGATE CAVITY-NESTER? .....................................................................................70 APPENDIX C. HOME RANGE AND HABITAT USE OF MEARNS’S SQUIRRELS ( TAMIASCIURUS MEARNSI ) WITHOUT THE CONSTRAINTS OF LARDERHOARDING..................................................................114 APPENDIX D. A STRANGER IN THE GENUS: LIFE-HISTORY AND BEHAVIORAL TACTICS OF MEARNS’S SQUIRRELS (TAMIASCIURUS MEARNSI ) ........................................................................................162 APPENDIX E. DISTRIBUTION OF ACTUAL AND RANDOM HOME RANGES OF ADULT MALE AND FEMALE MEARNS’S SQUIRRELS (TAMIASCIURUS MEARNSI ) IN THE NORTHERN PART OF THE SIERRA DE SAN PEDRO MÁRTIR.............................................................................................216 APPENDIX F. DETECTED PRESENCE OF MEARNS’S SQUIRRELS (TAMIASCIURUS MEARNSI ) DURING THE STUDY IN DIFFERENT AREAS OF THE SIERRA DE SAN PEDRO MÁRTIR ................................................218 7 LIST OF TABLES TABLE A1. Continental area for each state of Mexico (km 2), its relative size in the country (%), mean latitude, mean altitude (meters above sea level), mean annual temperature ( oC), mean annual precipitation (mm), area size of temperate forests (km 2), area size of tropical forests (km 2), annual wood production (m 3r), and human population growth rate ........................................................56 TABLE A2. List of species and subspecies of arboreal squirrels currently recognized in Mexico, their distribution, and their conservation status according to Secretaría de Medio Ambiente y Recursos Naturales (SEMARNAT), International Union for Conservation of Nature (IUCN), and Convention on International Trade in Endangered Species (CITES). Protection is specified for species and subspecies accordingly .........................................59 TABLE A3. Presence of the 14 species of arboreal squirrels ( Glaucomys , Sciurus , and Tamiasciurus ) recognized in Mexico by state based on published records ...............................................................................................................63 TABLE B1. Habitat characteristics used in univariate analyses to compare nest sites of Mearns’s squirrels ( Tamiasciurus mearnsi ) with random sites (availability), nest sites of males and females, and nest sites of females with maternity and nonmaternity nests, in a coniferous forest of the Sierra de San Pedro Mártir, Baja California, Mexico ............................................................................101 TABLE B2. Correlations between original characteristics selected in stepwise discriminant function analysis to compare nest sites of Mearns’s squirrels (Tamiasciurus mearnsi ) with random sites (availability), and nest sites of males and females, in the Sierra de San Pedro Mártir, Baja California, Mexico. Significance ( P < 0.017) is marked with an asterisk ........................................103 TABLE B3. Habitat characteristics used in stepwise discriminant function analyses to compare nest sites of Mearns’s squirrels ( Tamiasciurus mearnsi ) with random sites (availability), nest sites of males and females, and nest sites of females with maternity and nonmaternity nests, in a coniferous forest of the Sierra de San Pedro Mártir, Baja California, Mexico ......................................................104 TABLE B4. Principal component (PC) analysis used to compare nest sites of Mearns’s squirrels ( Tamiasciurus mearnsi ) with random sites (availability), nest sites of males and females, and nest sites of females with maternity and nonmaternity