EVALUATING STRATEGIES FOR RESTORING PARROTFISH POPULATIONS IN BELIZE Courtney Ellen Cox A dissertation submitted to the faculty at the University of North Carolina at Chapel Hill in partial fulfillment of the requirements for the degree of Doctor of Philosophy in the Department of Biology. Chapel Hill 2014 Approved by: John Bruno Corbin Jones Karl Castillo John Wares Peter White @2014 Courtney Ellen Cox ALL RIGHTS RESERVED ii ABSTRACT Courtney Ellen Cox: Evaluating Strategies for Restoring Parrotfish Populations in Belize (Under the direction of John F. Bruno) Parrotfish populations have declined throughout the Caribbean due to overfishing. Functional loss of these key grazers has contributed to a shift in reef community structure from coral to algal dominance. Marine protected areas (MPAs) and a national ban on the harvesting of herbivorous fishes are two management strategies implemented in Belize to recover parrotfish populations. Restricting or eliminating fishing is thought to promote high biomass of herbivorous fish that suppress macroalgae facilitating coral recruitment and population recovery. The success of these strategies not only depends on reduced fishing pressure, but also on the connectivity between parrotfish populations. My doctoral dissertation research examined the effectiveness of the MPA network in Belize and the ban on herbivorous fish harvesting in restoring fish communities and coral reef assemblages. From 2009 to 2013, I quantified the density and biomass of reef fishes, coral cover, and macroalgal cover at 16 reefs in Belize, including 8 protected sites and 8 unprotected sites. I then tested the effects of MPAs and the ban on herbivorous fish harvesting on coral reef community structure, projected parrotfish population recovery, and assessed connectivity between parrotfish populations in Belize and Honduras using nine nuclear microsatellite loci. Over the five year monitoring period, density or biomass increased for four parrotfish species. Population models indicate recovery is underway, and predict that a minimum of 9 years is needed to reach complete population recovery. Although iii the ban has been beneficial for parrotfish populations, my results also suggest that Belize’s current network of MPAs have not provided general and measurable ecological benefits for parrotfish biomass or the benthic community. I found only weak genetic population structure among populations within the Southern Mesoamerican Barrier Reef suggesting that these populations are connected via larval dispersal. My results highlight the importance of establishing a management approach that crosses international boundaries and suggest that improved enforcement of MPAs and additional restrictions on fishing effort may be necessary to restore parrotfish populations and coral reef health. iv ACKNOWLEDGEMENTS I would like to thank my doctoral advisor, John Bruno, for the opportunity to pursue my PhD and his continued support. John is truly an inspiration to me and I feel privileged to have worked with him over the past five years. I would also like to thank my doctoral committee members, Corbin Jones, John Wares, Karl Castillo, and Peter White, for their guidance in the lab and in the field. I want to give a special thanks to Corbin Jones for allowing me to join his lab and training me in molecular techniques. Also, a special thanks to Nathan Truelove and Steve Box at the Smithsonian Marine Institute for their invaluable collaboration, guidance for microsatellite development, and the use of the Smithsonian molecular laboratory. Completing this degree would never have happened without the support of my incredible lab mates that have become family to me. Lindsey Carr, Abel Valdivia, Rachel Gittman, Serena Hackerott, Emily Darling, and Ivana Vu helped me through field catastrophes, statistical nightmares, and painful manuscript writing. They have been my sounding board and at many times a much needed voice of reason. I sincerely thank all of them for their friendship and encouragement that kept me going. I am incredibly thankful for the many people in Belize and Honduras that provided support during field expeditions and who shared their knowledge and experiences that were v imperative for my understanding of local culture and the challenges of conservation. These people include Annelise Hagan (Southern Environmental Association), James Foley (Toledo Institute for Development and Environment), Melanie McField (Healthy Reefs for Healthy People), Diana Vasquez and Steve Canty (Centro de Estudios Marinos Honduras), Giaco Palavicini (Roatan Marine Park), Ian Drysdale (Healthy Reefs Initiative), Jenyy Myton (Coral Reef Alliance), Ana Quinonez (Bay Islands Conservation Association Utila), Oscar Maradiaga, Anais Monroy, the Belize Fisheries Department, Instituto Nacional de Conservación y Desarrollo Forestal, and Áreas Protegidas y Vida Silvestre who provided field and laboratory assistance, logistical support and necessary research permits. Finally, I want to thank my mom and dad for always believing in me and encouraging me to chase my dreams. Since I can remember, they have been telling me that I can accomplish anything I set my mind to and without them I would not be who or where I am today. vi TABLE OF CONTENTS LIST OF TABLES ............................................................................................................ X LIST OF FIGURES ........................................................................................................ XI CHAPTER 1: GENETIC TESTING REVEALS SOME MISLABELING BUT GENERAL COMPLIANCE WITH A BAN ON HERBIVOROUS FISH HARVESTING IN BELIZE ...........................................................................................13 Introduction ........................................................................................................................ 13 Methods ................................................................................................................................ 15 Sample and data collection ........................................................................................................ 15 DNA Extraction and PCR Amplification ............................................................................... 16 DNA Sequencing and Sequence Alignment ........................................................................ 16 Phylogenetic Analysis .................................................................................................................. 17 Statistical Analyses ....................................................................................................................... 17 Results ................................................................................................................................... 17 Discussion ............................................................................................................................ 22 Conclusions and Recommendations ..................................................................................... 28 CHAPTER 2: NATIONAL FISHING BAN PROMOTES RECOVERY OF PARROTFISH POPULATIONS ON CARIBBEAN CORAL REEFS ......................29 Introduction ........................................................................................................................ 29 Methods ................................................................................................................................ 32 Fish Censuses .................................................................................................................................. 32 Statistical Analysis ........................................................................................................................ 33 vii Stage-Structured Model .............................................................................................................. 34 Population Projection .................................................................................................................. 36 Results ................................................................................................................................... 37 Discussion ............................................................................................................................ 42 CHAPTER 3: ESTABLISHMENT OF MARINE PROTECTED AREAS ALONE DOES NOT RESTORE CORAL REEF COMMUNITIES .........................................46 Introduction ........................................................................................................................ 46 Methods ................................................................................................................................ 50 Study locations ............................................................................................................................... 50 Fish surveys ..................................................................................................................................... 51 Benthic surveys .............................................................................................................................. 53 Covariates ......................................................................................................................................... 53 Data Analysis ................................................................................................................................... 54 Results ..................................................................................................................................