ABSTRACT Borkhataria, Rena Rebecca. Ecological and Political Implications of Conversion from Shade to Sun Coffee in Puerto Rico. (Under the direction of Jaime Collazo.) Recent studies have shown that biodiversity is greater in shaded plantations than in sun coffee plantations, yet many farmers are converting to sun coffee varieties to increase short-term yields or to gain access to economic incentives. Through conversion, ecosystem complexity may be reduced and ecological services rendered by inhabitants may be lost. I attempted to quantify differences in abundances and diversity of predators in sun and shade coffee plantations in Puerto Rico and to gain insight into the ecological services they might provide. I also interviewed coffee farmers to determine the factors influencing conversion to sun coffee in Puerto Rico and to examine their attitudes toward the conservation of wildlife. Avian abundances were significantly higher in shaded coffee than in sun (p = 0.01) as were the number of species (p = 0.09). Avian species that were significantly more abundant in shaded coffee tended to be insectivorous, whereas those in sun coffee were granivorous. Lizard abundances (all species combined) did not differ significantly between plantations types, but Anolis stratulus was more abundant in sun plantations and A. gundlachi and A. evermanni were present only in shaded plantations. Insect abundances (all species combined) were significantly higher in shaded coffee (p = 0.02). I used exclosures in a shaded coffee plantation to examine the effects of vertebrate predators on the arthropods associated with coffee, in particular the coffee leaf miner (Leucoptera coffeela) and the flatid planthopper Petrusa epilepsis, in a shaded coffee plantation in Puerto Rico. Treatments included exclusion of birds, lizards, birds and lizards, and no exclusion. I found that birds had a significant effect on the abundance of Petrusa epilepsis and on insects > 5 mm in length. Combined insect species abundance as well as abundance of insects 2-5 mm and 5-10 mm varied significantly by treatment and removal of both birds and lizards had a larger effect than the removal of either taxa alone. Vertebrate predators exerted little influence over the coffee leaf miner, nor did they appear to appear with the leaf miner’s natural enemies, a complex of parasitoid wasps. In the survey of 100 coffee farmers, I found that sun coffee was substantially more prevalent than shaded coffee, both in number of farms and in land area devoted to its production. The average sun coffee plantation was significantly larger than the average shaded plantation (p = 0.02). Reasons for conversion from shade to sun coffee included higher yields, recommendations by agronomists, and incentives from the government. Farmers placed high conservation value on species that are rare or provide services to humans. Vertebrate insectivores were more diverse and abundant in shaded coffee and may provide a service to farmers by depressing total insect numbers and preventing outbreaks of the planthopper Petrusa epilepsis. Furthermore, they did not interfere with parasitism of the coffee leaf miner by parasitoid wasps. I conclude that governmental incentives for shaded coffee have a high probability of success, since coffee growers are highly dependent upon assistance from the government. ECOLOGICAL AND POLITICAL IMPLICATIONS OF CONVERSION FROM SHADE TO SUN COFFEE IN PUERTO RICO by RENA REBECCA BORKHATARIA A thesis submitted to the Graduate Faculty of North Carolina State University in partial fulfillment of the requirements for the Degree of Master of Science ZOOLOGY Raleigh 1993 APPROVED BY: Marcia Gumpertz Martha Groom Harold Heatwole Robert Rice Jaime Collazo Chair of Advisory Committee In loving memory of my mother, Carmen Rodriguez Borkhataria. ii Biography Rena Borkhataria grew up near Baltimore, Maryland, and began her higher education at St. John’s College in Annapolis. Following one semester at St. John’s, she decided to pursue a degree in Greek Classics at the University of Maryland, Baltimore County. Two years later, she reconsidered her career choice upon realizing that classics instructors are notoriously long-lived and that they never become out-dated. She left school and moved to Tucson, Arizona, to consider her options. While working at a local coffee shop, Rena met a café regular, who happened to be a wildlife biologist for the Forest Service. Inspired by the job description, Rena enrolled in the Wildlife Ecology program at the University of Arizona and graduated 3 years later with highest honors. She then set off for a summer internship with the U.S. Fish and Wildlife Service in Arlington before beginning her master’s degree in Zoology at North Carolina State University. Rena is now enrolled in the Graduate Program in Ecology at Duke University. iii Acknowledgements There are many people who have helped me reach this goal. First and foremost, I would like to thank my family, the Richardsons, for their love and support throughout the years. I would also like to thank the other families who were there when I needed them, most notably the Rodriguez family and the Coxes. I could not have done this project without the help of my many field assistants. Thanks to Adrian Jordan for his huge contribution to this project. Thanks also to Veronica Cordova, Mary Hershdorfer, and Bill Monohan. And I would like to give a special thanks to los monos, Liz Dunn, Sadie Rosenthal, and Scott Smith, for making my last 6 months in Puerto Rico so productive and enjoyable. I would like to thank my advisor, Jaime Collazo, for all of his support during the last three years. Jaime gave me the freedom and the resources to make my own decisions and to learn from them; the results lie herein. Wendy Moore also has my undying gratitude. Likewise, I am grateful to my committee members, Martha Groom, Marcia Gumpertz, Harold Heatwole, and Robert Rice, and my field-mate, Jim Saracco, for their insightful comments and suggestions. I received funding and support from a National Science Foundation Graduate Fellowship and a Harry S. Truman Scholarship. My project was also supported by the Puerto Rico Department of Natural Resources and the Environment, the U.S. Fish and Wildlife Service, the North Carolina Cooperative Fish and Wildlife Research Station, and the Biological Resources Division of the U.S. Geological Survey. iv Finally, I would like to thank my husband, Colin Saunders, for his patience, love, and support and for all of his other great qualities that have helped me through this final phase of my master’s, and Hazel, who can always make me laugh. v TABLE OF CONTENTS Page LIST OF TABLES . viii LIST OF FIGURES . x CHAPTER 1. Abundances of birds, lizards, and insects in shaded and sun coffee: Implications for biological control of coffee pests . 1 Abstract . 1 Introduction . 2 Methods . 6 Study Areas . 6 Avian sampling . 8 Lizard sampling . 10 Arthropod sampling . 12 Wasp sampling . 14 Results . 15 Avian abundance . 15 Lizard abundances . 18 Arthropods . 19 Parasitoid wasps . 20 Discussion . 21 Works Cited . 26 CHAPTER 2. An experimental evaluation of ecological services rendered by vertebrate insectivores in a shaded coffee plantation in Puerto Rico . 49 Abstract . 49 Introduction . 50 Methods . 52 Study Area . 52 Experimental design . 53 Community monitoring procedures . 55 Statistical analyses . 57 Results . 58 Numerical response . 58 Body size class response . 59 Numerical response by order . 60 Pest response . 60 Predatory taxa response . 61 Bananaquit effect . 61 Leaf damage response . 62 Discussion . 62 vi Impact of birds and lizards on coffee insects . 62 Response of coffee pests to removal of predators . 64 Effects on plant health . 66 Implications for biological control . 66 Works Cited . 69 CHAPTER 3. Social and Political Implications of Conversion to Sun Coffee in Puerto Rico . 94 Abstract . 94 Introduction . 95 Methods . 100 Results . 102 Background . 103 Land use and agricultural practice . 104 Participation in institutionalized programs . 106 Challenges to farmers . 107 Conservation values . 107 Sun versus Shaded Coffee . 108 Discussion . 111 Works Cited . 118 APPENDICES . 129 Appendix A. Mean detections/10 min. by season averaged for 3 shaded coffee plantations, 1999-2000 . 130 Appendix B. Mean detections/10 min. by season averaged 3 sun coffee plantations, 1999-2000 . 132 Appendix C. Closed population model (CAPTURE) results by species for 3 sun and 3 shaded plantations, 2000: closure test, model selection, and population estimation . 134 Appendix D. Open Population Model A (JOLLY) by species for 3 sun and 3 shaded plantations, 2000 . 135 Appendix E. Questionnaire for Coffee Farmers . 136 Appendix F. Answers to Survey Question 4 . 143 Appendix G. Answers to Question 41 . 146 vii LIST OF TABLES Pages Chapter 1 1. Farm elevation, location, and size . 32 2. Total counts in 3 shade and 3 sun coffee over all seasons, 1999-2000 . 33 3. Fixed effects table for farm type, season, and type by season interaction . 34 4. Overall lizard density in 3 shade and 3 sun coffee plantations, 2000, using closed and open population estimates . 37 5. Lizard density by species in 3 shade and 3 sun coffee plantations, 2000, using closed and open population estimates . 38 6. Mean insects per tree in 3 shade and 3 sun plantations, 1999, sampling 100 leaves/tree on 14 trees at all bird point count stations . 39 7. Mean insects per tree in 3 shade and 3 sun plantations, 2000, sampling 100 leaves/tree on 14 trees at all bird point count stations . 40 8. Parasitoid wasp complex reared from 3 sun and 3 shaded coffee farms, 2000 . 41 Chapter 2. 1. Effect tests, least-squares means of treatment effect and standard errors of the least-squares means by size class . 74 2. Effect tests, least-squares means of the treatment effect, and standard errors of the least-squares means by Order . 75 3.