The University of Maine DigitalCommons@UMaine Electronic Theses and Dissertations Fogler Library 8-2007 Assessment of the Flame Angelfish (Centropyge loriculus) as a Model Species in Studies on Egg and Larval Quality in Marine Fishes Chatham K. Callan Follow this and additional works at: http://digitalcommons.library.umaine.edu/etd Part of the Aquaculture and Fisheries Commons, and the Oceanography Commons Recommended Citation Callan, Chatham K., "Assessment of the Flame Angelfish (Centropyge loriculus) as a Model Species in Studies on Egg and Larval Quality in Marine Fishes" (2007). Electronic Theses and Dissertations. 126. http://digitalcommons.library.umaine.edu/etd/126 This Open-Access Dissertation is brought to you for free and open access by DigitalCommons@UMaine. It has been accepted for inclusion in Electronic Theses and Dissertations by an authorized administrator of DigitalCommons@UMaine. ASSESSMENT OF THE FLAME ANGELFISH (Centropyge loriculus) AS A MODEL SPECIES IN STUDIES ON EGG AND LARVAL QUALITY IN MARINE FISHES By Chatham K. Callan B.S. Fairleigh Dickinson University, 1997 M.S. University of Maine, 2000 A THESIS Submitted in Partial Fulfillment of the Requirements for the Degree of Doctor of Philosophy (in Marine Biology) The Graduate School The University of Maine August, 2007 Advisory Committee: David W. Townsend, Professor of Oceanography, Advisor Linda Kling, Associate Professor of Aquaculture and Fish Nutrition, Co-Advisor Denise Skonberg, Associate Professor of Food Science Mary Tyler, Professor of Biological Science Christopher Brown, Professor of Marine Science (Florida International University) LIBRARY RIGHTS STATEMENT In presenting this thesis in partial fulfillment of the requirements for an advanced degree at The University of Maine, I agree that the Library shall make it freely available for inspection. I further agree that permission for “fair use” copying of this thesis for scholarly purposes may be granted by the Librarian. It is understood that any copying or publication of this thesis for financial gain shall not be allowed without my written permission. Signature: Date: ASSESSMENT OF THE FLAME ANGELFISH (Centropyge loriculus) AS A MODEL SPECIES IN STUDIES ON EGG AND LARVAL QUALITY IN MARINE FISHES By Chatham K. Callan Thesis Advisors: Dr. David W. Townsend and Dr. Linda J. Kling An Abstract of the Thesis Presented in Partial Fulfillment of the Requirements for the Degree of Doctor of Philosophy (in Marine Biology) August, 2007 This project sought to determine if flame angelfish (Centropyge loriculus) could serve as models in examination of environmental and dietary effects on egg quality in marine fishes. Evaluation of 21 marine ornamental species identified flame angelfish as being amenable to egg quality research, due to their rapid conditioning and frequency of spawning. At the onset of this project, accidental copper introduction to broodstock systems required assays to determine the effects of copper exposure on survival and reproduction. Flame angelfish exhibited accute sensitivity to copper, as 60% of fish exposed to 0.25mg/L died within 12 hours of exposure. Likewise, fish exposed to 0.20 and 0.15mg/L exhibited 40% mortality within 48 hours. Furthermore, copper at 0.10mg/L significantly reduced fecundity and negatively affected embryonic development among orchid dottyback (Pseudochromis fridmani) broodstock. A series of experiments was conducted to determine the effects of water chemistry and broodstock diet on flame angelfish reproduction, as well as to compile baseline spawning performance and egg quality data for this species. Results revealed that water chemistry significantly affected spawning performance, as fish maintained in sterilized ocean water exhibited greater fecundity, egg fertilization rates and egg viability than pairs held in water from saltwater wells. However, sterilization of ocean water by chlorine at levels >25ppm significantly reduced fecundity and egg fertilization. Flame angelfish readily adapted to a variety of formulated feeds and results from current experiments demonstrated that maternal diet significantly affected egg quality. Fish that were fed a diet containing 3.63% n-3 highly unsaturated fatty acids (HUFA) exhibited significantly greater fecundity, fertilization rates and egg viability than fish that were fed diets with lower n-3 HUFA levels. Furthermore, over-all egg quality, egg and larval size metrics, and survival to yolk-exhaustion, were not significantly different between fish fed the High n-3 and Control diets. Daily egg production from 18 pairs was recorded over a 20-month period and averaged 1,000-1,500 eggs per female. Mean daily egg fertilization rates ranged from 60-80% and hatch rates were normally 80%. Egg quality characteristics responded to maternal dietary changes within weeks, indicating that experiments of shorter duration than those currently reported may be possible. DEDICATION This dissertation is dedicated in loving memory of my sister Jaclyn Rose Callan. She inspired me to do my best at all times and always made me laugh, even when I didn’t feel like it. She remains in my heart forever. This is for you Jackie. ii ACKNOWLEDGMENTS Throughout this dissertation research and over the course of my graduate career, there have been many individuals who have helped, supported and encouraged me along the way. I would like to thank my advisor, Dr. David Townsend, for having the vision necessary to get this, seemingly improbable, project of studying tropical fish in Maine initiated. Who would have suspected that a practical joke (you never did find my exam), an impromptu visit to a marine ornamental fish farm, and a lone dottyback in a drainage ditch could have led to so much? Thank you for supporting this project and me so whole- heartedly, despite the skepticism and limited resources I know you encountered. Thank you also for the personal support and friendship you have provided to both Jessica and me during our time in Maine and in Hawaii. I wish to thank my co-advisor, Dr. Linda Kling, for her continued support of my work over the years and invaluable contributions to this research. Thank you for your assistance with all my many nutrition questions, and for guiding me through a very complex and difficult field. Despite the challenges I encountered over this period, your excitement and enthusiasm have been a real encouragement to me. Although we did not get to test all the parameters we had hoped to during this project, I am looking forward to working with you in the future to address those unanswered questions and more. I would also like to thank Dr. Denise Skonberg, Dr. Mary Tyler and Dr. Christopher Brown for agreeing to serve on my committee and for their helpful, insightful and constructive contributions to this dissertation. Through your support, guidance and encouragement I have been able to overcome many obstacles in this iii exciting and challenging field of research. I am very grateful for the time, patience and energy you contributed in helping me realize this achievement. Continued appreciation is also expressed to Dr. Charles Laidley for enabling me to complete my dissertation while working at the Oceanic Institute. I am grateful for the opportunity to continue pursuing the research on marine ornamentals in which you paved the way. Thank you for allowing me the chance to explore new ideas and for valuing my contributions to the finfish department. It has been a privilege working with you that I hope extends for many years to come. I also wish to thank Kenneth Liu and the technical staff at the Oceanic Institute finfish department for supporting my research by providing the unglamorous technical assistance that is vital to completing studies such as these. It would have been impossible to initiate this project without the help, support and team-effort provided by my good friend and colleague Søren Hansen. I am forever grateful for your assistance in getting this crazy idea off the ground and for your determination to see it through. Despite all the bumps in the road, I’m proud of what we accomplished and I know I could not have done it without you. I wish you the best in your future endeavors with Sea & Reef! Finally, I want to express my sincerest thanks and utmost appreciation for all my family and for my wife who supported me through this extremely challenging, but incredibly rewarding, period of my life. I would not have made it through without the love, support and encouragement of my siblings, parents and grandparents. Jessica, thank you for believing in me, loving me and supporting me through this time. I know I could not have gotten as far as I have without you. iv TABLE OF CONTENTS ACKNOWLEDGMENTS ............................................................................................... iii LIST OF TABLES ......................................................................................................... xiii LIST OF FIGURES ......................................................................................................... xv Chapter 1. INTRODUCTION ................................................................................................. 1 1.1. The Marine Aquarium Industry ...................................................................... 1 1.2. Angelfish Taxonomy, Distribution and Reproductive Biology ...................... 4 1.2.1. Reproductive Biology ........................................................................... 6 1.2.2. Spawning Rituals .................................................................................