Effects of Scale Insects on Forest Dynamics in Tropical Montane Oak
Total Page：16
File Type：pdf, Size：1020Kb
Florida State University Libraries Electronic Theses, Treatises and Dissertations The Graduate School 2012 Effects of Scale Insects on Forest Dynamics in Fragmented Tropical Montane Oak Forests of Veracruz, Mexico Heather A. Gamper Follow this and additional works at the FSU Digital Library. For more information, please contact [email protected] THE FLORIDA STATE UNIVERSITY COLLEGE OF SOCIAL SCIENCE AND PUBLIC POLICY EFFECTS OF SCALE INSECTS ON FOREST DYNAMICS IN FRAGMENTED TROPICAL MONTANE OAK FORESTS OF VERACRUZ, MEXICO By HEATHER A. GAMPER A Dissertation submitted to the Department of Geography in partial fulfillment of the requirements for the degree of Doctor of Philosophy Degree Awarded: Spring Semester, 2012 Heather A. Gamper defended this dissertation on March 30, 2012. The members of the supervisory committee were: Anthony J. Stallins Professor Co-Directing Dissertation James Elsner Professor Co-Directing Dissertation Brian Inouye University Representative Xiaojun Yang Committee Member Victor Mesev Committee Member The Graduate School has verified and approved the above-named committee members, and certifies that the dissertation has been approved in accordance with the university requirements. ii to my Grandmother - Virginia Marie Gardella (1919 -2010) iii ACKNOWLEDGMENTS This work is not mine alone, for its success weighs on many others. The origination of studying scale insects began in the countryside of the Dominican Republic, where I was a part of a group of ornithologists who discovered and cooperatively described a unique phenomenon of birds feeding from scale insect secretions. I was the only one in this group passionate, or perhaps foolish enough, to focus my future research efforts on such an odd topic. I was able to search for other occurrences of this phenomenon after being accepted as a Biology Master’s degree student by Dr. Suzanne Koptur at Florida International University. Much of my understanding of plant-animal interactions was cultivated by Suzanne, a wise and motherly mentor. Suzanne gave me the confidence to explore the tropics in pursuit of scale insects which conceptually began my life as an independent scientist. I am thankful in this intricate network of life, our webs collided. At the same time I collided with my life’s best friend and husband, Andres, who has supported me and has been by my side from the moment we met. Living in a foreign country could be uncomfortable and intimidating, but it rarely was because of two amazing women: Mariana Cuautle Arenas and Cecilia Castelazo. They welcomed me into their homes for many years, fed me the most delicious food I have ever eaten and incorporated me into their group of friends. Night after night, after working in the forest, I came home to a place where I have never lived so contently within the glow, laughter and pulse of Mexico. At the Institute of Ecology in Xalapa Mexico, I was fortunate to find two tremendous mentors: Dr. Guadalupe Williams-Linera, and Dr. Jose ’Pepe’ Garcia Franco who provided invaluable logistical support. Throughout the years this work was completed, there were many people who assisted me in the field: Victor Ruiz Mandoval, Miriam Ferrer, Mariana Cuautle, Cecilia Castelazo, Socorro Jiminez, Christopher Brown, and Andres Plata. I owe the decision to pursuing my Doctoral Degree at FSU, to Dr. Brian Inouye in the Biology Department. Brian gave me wise guidance for studying this ecological interaction and I am grateful to have been given the opportunity to work with him and look forward to working with him in the future. Within the geography department, I am appreciative of the teaching, advising, and guidance of Dr. Elsner, Dr. Yang, Dr. Mesev, Dr. Tschinkel and Dr. Steinberg. I am particularly thankful to Dr. Anthony ’Tony’ Stallins for his patience with me and care in crafting me into a geographer. I am especially thankful for his reading and editing of my work in a fashion that exemplifies his capabilities as an advisor. During the analysis and writing stage of my dissertation, I mentored an undergraduate student, Brandy Safell. In addition to completing an independent research project in den- iv drochronology, Brandy was extremely eager and helpful in learning and assisting with my dissertation research. Brandy helped create maps and participated in statistical analyses that we jointly presented at meetings. Brandy is a brilliant student and I am fortunate to have had the opportunity to work with her. Many beekeepers deserve thanks for increasing my knowledge of the subject and making the beekeeping chapter more pertinent. In particular, I thank Kelly Watson for sharing with me her research at FSU and introducing me to the bees. I also owe much thanks to Donald Smiley in Wewahitchka, Florida for making me a beekeeper. If it were not for a strong network of friends and family, this work may have never been completed. Kim McClellan allowed me to ease back into teaching shortly after my daughter Celeste Wren was born by accepting her with loving arms into her office while I gave weekly lectures. I must thank my parents Robert and Virginia Gamper and my husband Andres Plata. Andres has kept me going and has assisted me with this work in both intellectual and spiritual ways. It is with his support that I was capable of simultaneously pouring every bit of energy I had into both my love for him and Celeste and my passion for science. Thank you. v TABLE OF CONTENTS ListofTables........................................ ix ListofFigures ....................................... x Abstract........................................... xiv 1 Introduction 1 1.1 Scale insects in tropical montane cloud forest of Veracruz, Mexico . 1 1.2 Studysite..................................... 2 1.3 Dissertation organization . 6 2 Honeydew Foraging by Birds in Tropical Montane Forests and Pastures of Mexico 8 2.1 Abstract...................................... 8 2.2 Introduction.................................... 8 2.3 Methods...................................... 10 2.3.1 Study area . 10 2.3.2 Bird foraging observations in oak trees . 10 2.3.3 Statistical analysis . 12 2.4 Results....................................... 12 2.4.1 Bird foraging . 12 2.4.2 Interspecific interactions and resource defense . 14 2.4.3 Comparison of forest and pasture . 14 2.5 Discussion..................................... 14 3 Alteration of forest structure modifies the distribution of scale insect, Stigmacoccus garmilleri, in Mexican tropical montane cloud forests 19 3.1 Abstract...................................... 19 3.2 Introduction.................................... 20 3.3 Methods...................................... 24 3.3.1 Studysite................................. 24 3.3.2 Scale insect density measures . 24 3.3.3 Anal filament and honeydew drop measures at observation trees . 26 3.3.4 Anal filament growth rate at observation trees . 27 3.4 Results....................................... 27 3.4.1 Anal filament and honeydew drop measurements . 27 3.4.2 Anal filament growth . 31 vi 3.5 Discussion..................................... 34 3.5.1 Scale insect distribution . 34 3.5.2 Honeydew volume/concentration . 35 3.5.3 Anal filaments . 35 3.6 Conclusions.................................... 36 4 Explaining the relationship between chronic scale insect herbivory and tree growth in fragmented forests of Veracruz, Mexico 38 4.1 Abstract...................................... 38 4.2 Introduction.................................... 39 4.2.1 Forest change and scale insect distribution . 40 4.3 Methods...................................... 41 4.3.1 Dendrochronology in the tropics . 41 4.3.2 Study area . 43 4.3.3 Field data collection . 43 4.3.4 Sample preparation and measurements . 45 4.3.5 Pithflecks................................. 46 4.4 Results....................................... 46 4.5 Discussion..................................... 55 5 A socioecological critique of beekeeping as mechanism to offset deforesta- tion: the importance of context for honey production in rural Veracruz, Mexico 65 5.1 Abstract...................................... 65 5.2 Introduction.................................... 66 5.3 Ecological Knowledge . 67 5.3.1 Land-use change and landscape configuration . 68 5.3.2 Non-native pollinators . 69 5.3.3 Selectingabeespecies.......................... 70 5.3.4 Access to floral resources . 70 5.3.5 Mobility of Beekeeping . 71 5.4 Socioecological context . 71 5.4.1 Social networks . 71 5.4.2 Addressing economic opportunity . 72 5.4.3 Gender roles - women participants . 73 5.4.4 Negotiating access to forage . 73 5.4.5 Pests, pathogens and africanized bees . 74 5.4.6 Challenges to marketing honey . 74 5.4.7 Non-floral resources . 75 5.5 Casestudyexample: VeracruzMexico . 78 5.6 Conclusions.................................... 82 6 Conclusions 83 vii A Maps illustrating the distribution of scale insect, Stigmacoccus garmilleri in tropical montane forests of Chiconquiaco, Mexico 86 A.1 Methods...................................... 86 A.1.1 GPS data collection . 86 A.1.2 Geovisualization . 86 Bibliography ........................................ 95 Biographical Sketch . 115 viii LIST OF TABLES 2.1 Bird visits to scale insect honeydew on oak trees in tropical montane forest and pasture areas of Chiconquiaco, Veracruz, Mexico. 13 2.2 Summary of birds and their feeding behavior on oak trees in tropical montane forest and pasture areas of Chiconquiaco, Veracruz, Mexico. 16 3.1 Means, standard deviations, minimum and maximum values for honeydew- drop volume, sugar concentrations,