The University of Maine DigitalCommons@UMaine Electronic Theses and Dissertations Fogler Library Spring 3-10-2016 Highly Seasonal Reproduction in Desmophyllum dianthus from the Northern Patagonian Fjords Keri Feehan University of Maine, [email protected] Follow this and additional works at: http://digitalcommons.library.umaine.edu/etd Part of the Marine Biology Commons Recommended Citation Feehan, Keri, "Highly Seasonal Reproduction in Desmophyllum dianthus from the Northern Patagonian Fjords" (2016). Electronic Theses and Dissertations. 2433. http://digitalcommons.library.umaine.edu/etd/2433 This Open-Access Thesis 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. HIGHLY SEASONAL REPRODUCTION IN DESMOPHYLLUM DIANTHUS FROM THE NORTHERN PATAGONIAN FJORDS By Keri A. Feehan B.S. University of Maine, 2013 A THESIS Submitted in Partial Fulfillment of the Requirements for the Degree of Master of Science (in Marine Biology) The Graduate School The University of Maine May 2016 Advisory Committee: Rhian G. Waller, Professor of Marine Sciences, Advisor Kevin Eckelbarger, Professor of Marine Sciences Bob Steneck, Professor of Marine Sciences and Oceanography THESIS ACCEPTANCE STATEMENT On behalf of the graduate Committee for Keri A. Feehan I affirm that this manuscript is the final and accepted thesis. Signatures of all committee members are on file with the Graduate School at the University of Maine, 42 Stodder Hall, Orono, Maine. Dr. Rhian G. Waller, Associate Professor March 2nd, 2016 ii © 2016 Student’s name All Right Reserved iii 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 copy or publication of this thesis for financial gain shall not be allowed without my written permission. Signature: Date: HIGHLY SEASONAL REPRODUCTION IN DESMOPHYLLUM DIANTHUS FROM THE NORTHERN PATAGONIAN FJORDS By: Keri A. Feehan Thesis Advisor: Dr. Rhian G. Waller An Abstract of the Thesis Presented in Partial Fulfillment of the Requirements for the Degree of Master of Science (in Marine Biology) May 2016 The purpose of this study was to determine the basic reproductive biology and seasonality of the Patagonian fjord coral Desmophyllum dianthus. Desmophyllum dianthus is a deep-sea solitary scleractinian found throughout the world’s oceans and an important benthic habitat builder. The Chilean Patagonian fjords are the only known location where this species occurs >50 m and thus are the only place to collect samples efficiently, effectively and economically. Corals were collected via SCUBA approximately every three months (when conditions permitted) from August 2012 to September 2013 from three sites within the Northern Patagonian fjords – Lilihuape (n=76) and Punta Huinay (n=59) in the Comau fjord, and Punta Mamurro (n=44) in Reñihue fjord. The objectives of this study were to determine sexuality, reproductive mode, oocyte size, fecundity and seasonality using histological techniques. Environmental data (temperature, salinity and light) was also analyzed to compare to seasonal reproductive trends and bring reproductive data into context. This study determined that Desmophyllum dianthus is dioecious (gonochoristic), having both male and female individuals. This species is also highly seasonal, spawning in the austral winter (August) and beginning gamete production in early spring. The fjord was coolest and most saline in August 2012, potentially cueing spawning. No planula larvae were found in any of the 8,000 histological sections. Due to the presence of late stage oocytes in August 2012, it is likely D. dianthus’s mode of reproduction is spawning rather than brooding. However this distinction could not be determined in this study. Oogenesis starts in September producing previtellogenic oocytes (size range: 25 – 200 μm) that slowly developed into vitellogenic oocytes by June. Vitellogenic oocytes ranged from 200 – 380 μm. Fecundity is relatively high compared to other deep-sea scleractinians, ranging from 2,448 (± 5.13 SE) to 172,328 (±103.67 SE) average potential oocytes per polyp. This research provides the first insight into Desmophyllum dianthus reproductive biology and yields an important baseline for continuing work on this benthic habitat builder in the Chilean fjords, and in the deep ocean. ACKNOWLEDGEMENTS This research would not have been possible without the collaboration between the University of Maine and the Punta Huinay Scientific Field Station. I would like to thank National Geographic and the National Science Foundation for the finical support for this project. A tremendous thank you to Rhian G. Waller, Laura Grange, Chris Riguad, Vreni Haussermann, Gunter Forsterra and all divers & scientists at the Punta Huinay scientific field station who collected the samples for this study. I would also like to thank undergraduates M. Halfman, A. Rossin, and E. Hartill for their help with decalcifications and staining. I would like to thank Damian Brady for over a 9,000 data points worth of salinity conversions. I am deeply grateful to my friends, family and fiancé Travis Conley for their support and love over the last two years. To my committee, Kevin Ecklebarger and Bob Steneck it has been a joy to know you and learn from you over the last several years, thank you for the all the great conversations and inspiration. To my advisor and mentor Rhian Waller, thank you for cultivating my passion for marine biology, thank you for every opportunity you have put my way, and thank you for your patience, kindness and forthright honesty. It is a pleasure to know you; you have helped me learn but most importantly you have helped me grow into the scientist I am today. I will be forever grateful for you and all who I have meet on my journey at the University of Maine. iv TABLE OF CONTENTS ACKNOWLEDGEMENTS…………………………………………………………………………………iv LIST OF TABLES………………………………………………………………………………………….…vii LIST OF FIGURES……………………………………………………………………………………….…viii CHAPTER 1. INTRODUCTION……………………………………………………….………………………………….1 2. HYPOTHESIS……………………………………………………………………….……………………….8 3. MATERIALS AND METHODS……………………………………………………………..............9 4. RESULTS……………………………………………………………………………...….…………………14 4.1. Environmental Analysis…………………………………………………………….…………14 4.1.1. Lilihuape………………………………………………………………………………........14 4.1.2. Punta Huinay………………………………………………………….………………..….14 4.1.3. Punta Mamurro……………………………………………………………………….…..15 4.2. Gametogenesis…………….………………………………………………………………….….18 4.3. Fecundity…………………………………………………………………………………….………22 4.4. Size and fecundity………………………………………………………………………….……23 5. DISCUSSION……………………………………………………………………….…....…….……......27 REFERENCES………………………………………………………………………………..…………….34 v APPENDIX A. SUMMARY OF REPRODUCTIVE DATA BY SITE………….…….……..40 APPENDIX B. SUMMARY OF FECUNDITY DATA……………………………....………….47 APPENDIX C. SUMMARY OF COLD-WATER SCLERACTINIAN REPRODUCTIVE DATA………….…………………………………………………………………….48 BIOGRAPHY OF THE AUTHOR…………………………………………………….….…………..50 vi LIST OF TABLES Table A.1. Summary of size parameters and sex of Desmophyllum dianthus individuals collected at Lilihuape in the Comau fjord….…………..….40 Table A.2. Summary of size parameters and sex of Desmophyllum dianthus individuals collected at Punta Huinay in the Comau fjord.…….…….43 Table A.3. Summary of size parameters and sex of Desmophyllum dianthus individuals collected at Punta Mammuro in the Renihue fjord..…..45 Table A.4. Summary of size parameters and sex of Desmophyllum dianthus individuals collected at Cabudahue in the Renihue fjord……………..46 Table B.1. Summary of fecundity (opp), average oocyte diameter, polyp area and number of reproductive mesenteries in females from all locations……………………………………………………………………………………….47 Table C.1. Summary of sexuality, mode of reproduction and maximum oocytes sizes in all deep-sea Scleractinians published to date………………………………………………………………………………………………………48 vii LIST OF FIGURES Figure 1. Map of study sites in the Comua and Reñihue fjords, Southern Chile ……………………………………………………………………………………..…..10 Figure 2. Height (H), length (L) and width (W) measurement specifications for Desmophyllum dianthus..……………………………..…………..…..12 Figure 3. Histological sections of Desmophyllum dianthus reproductive anatomy………………………………………………….…………………………...13 Figure 4. Seasonality at Lilihuape in terms of environmental and reproductive data from August 2012 to September 2013….……………………...16 Figure 5. Seasonality at Punta Huniay in terms of environmental and reproductive data from August 2012 to September 2013……………….....17 Figure 6. Seasonality at Punta Mamurro in terms of environmental and reproductive data from August 2012 to September 2013…………………..18 Figure 7. Percent frequency of oocyte diameter per month from females collected in the Comau fjord (Lilihuape and Punta Huinay collection sites)……………………………………………………………..…....21 viii Figure 8. Percent frequency of oocyte diameter per month from females collected in the Comau fjord (Lilihuape and Punta Huinay collection sites)……..….…………………………………………………..…...22 Figure 9. Average potential fecundity by month at Lilihuape..…………………..24 Figure 10. Average potential fecundity in the Comau fjord in June 2013………………………………………………………………………………………………………....24