ECOLOGICAL STUDIES OF CORAL REEF ECOSYSTEM AT MALVAN, WEST COAST OF INDIA Thesis submitted to the Goa University For the award of the degree of Doctor of Philosophy In Marine Sciences By Kalyan De Under the supervison of Dr. Baban Ingole School of Earth, Ocean, and Atmospheric Sciences, Goa University (Biological Oceanography Division, CSIR – National Institute of Oceanography, Goa) January 2020 i Dedicated to my Parents and Gurus गु셁र्ब्रह्मा गु셁र्वर�ुुः गु셁र्देवो महेश्वरुः । गु셁ुःसाक्षात् परर्ब्ह्म तस्मै श्रीगुरवे नम: ॥ (आपर्दशंकराचायव गु셁स्तोत्रम्) ii Declaration As required under the university ordinance OA.19, I hereby state that the present thesis entitled “Ecological Studies of Coral Reef Ecosystem at Malvan, West Coast of India” is my original contribution and the same has not been submitted for any other degree, diploma, associate-ship, fellowship or similar titles in any universities or institutions on any previous occasion. To the best of my knowledge, the present study is the first comprehensive work of its kind from the area mentioned. Literature related to the scientific objectives has been cited. Due acknowledgments have been made wherever facilities and suggestions have been availed of. Place: Goa University, Goa Kalyan De Date: 10th August 2020 iii Certificate This is to certify that the thesis entitled “Ecological Studies of Coral Reef Ecosystem at Malvan, West Coast of India” submitted by Mr. Kalyan De to the School of Earth, Ocean, and Atmospheric Sciences, Goa University for the degree of Doctor of Philosophy in Marine Sciences, is based on original work carried out by him under my supervision. The thesis, or any part thereof has not been previously submitted for any other degree or diploma in any university or institution. Dr. Baban Ingole Former Chief Scientist and Head, Biological Oceanography Division, CSIR-National Institute of Oceanography, Dona Paula, Goa-403004 Place: Goa University Date: 10th August 2020 iv Acknowledgments Starting a Ph.D. project is a challenge; finishing a Ph.D. degree is an even bigger one, and it would not be possible without many helpful and encouraging people. In my comparatively long journey of doctoral research, many people have come out and helped me towards fulfilling my objectives. First of all, I thank Prof. Baban Ingole (Former Head Biological Oceanography Division, CSIR- National Institute of Oceanography, Goa) for accepting me as a Ph.D. student. His experience, knowledge, and inspiring motivation guided and helped me throughout this Ph.D. project. Besides this, he also made sure that I should grow in every aspect of the research field, including a good orator during scientific presentations. I express my sincere gratitude to my Department Research Committee, Dr. Narsinh Thakur (the VC nominee), and Prof. H.B. Menon (Dean SEOAS), Prof. Malapati K. Janarthanam (former Dean), Prof. C.U. Rivonkar, Prof. V. M. Matta, Prof. G.N. Nayak for critically reviewing my progress report and constructive comments to keep a tight check on my work. I’m thankful to the Vice-Chancellor, Goa University, Dean of School of Earth, Ocean, and Atmospheric Sciences and the staff of the Marine Science Department, Goa University, for all the help and administrative support. I take this opportunity to thank the present Director of the CSIR-NIO, Dr.Sunil Kumar Singh, and former directors for the research infrastructure. I am also thankful to the office staff of CSIR-NIO for timely help during this period. I also acknowledge the Department of Science and Technology, Govt. of India, for providing fellowship support through the DST-INSPIRE program. I am grateful to Dr. Rusell E. Brainard of NOAA-PIFSC, Dr. Tom Oliver and Dr. Eric DeCarlo, for supervising me at the NOAA-Pacific Island Fisheries Science Center, Hawaii. Besides this, I am also thankful to Fulbright Fellowship Board for providing the fellowship for nine months to carry out part of my research work at NOAA and University of Hawaii. Thanks so much to all my great friends in Hawaii, Ari, Hannah, Lucie, Noah, Roberto for the unstated supportive atmosphere. I would convey my thanks, Prof. Baruch Rinkevich, for accepting me in his lab and allow me to work under his supervision. I want to thank all the lab-mates and my friends at ILOR, Jacob, Guy, v Claudette, Ziva, Amalia, Eitan, Nir, Elad, Yossi, Shabhy, Oshrat for all your support and beautiful memories. I would like to acknowledge the help and support of Dr. Durbar Ray in seawater nutrient analysis. Also, heartfelt thanks to Lobsang Tsering, Rahul Nagesh, Afreen Hussain, Vishal Patil, Liju Thomas, Sabyasachi Sautya, Gangadhar Tambre, Akshay Naik, Amit Patil, Laxman Pujari for tireless day-night work during numerous field trip, and sample analysis. I am thankful to Dr. Mandar Nanajkar for laboratory and financial support. Thank you, Sir, for all the help and scientific inputs till the end. Sambhaji, buddy, you have been around from day one of my Ph.D. journey, and all of this work would not have been the same without you. Thanks for your help in the underwater field to the lab, caring, support, and scientific input. I was fortunate enough to have wonderful people like Dr. Sanitha, Dr. Ravail, Dr. Periasamy, Ivy, Neelam, Santosh, Dr. Kuldeep in our lab. Thank lads for giving many memorable moments of my Ph.D. days. Additionally, my friends Awkash, Arnab, Azraz, Amit, Aditi, Dharmendra, Diksha, Govind, Gowri, Jacky, Medhavi, Mithilesh, Mintu, Pratirupa, Pankaj, Pabitra, Suchandan are fantastic guys and have supported me in many ways during the last few years. I wish to acknowledge with gratitude the continued support given by my parents and brother during the project. Finally, I wish to thank The Almighty for this beautiful life all the affection and knowledge I have gained living here. Kalyan De vi Preface Coral reefs are one of the most diverse and complex ecosystems in tropical seas, providing sustainable ground to millions of marine biotas to settle, forage, spawn and nurture their juveniles (Moberg & Folke, 1999, Hoegh-Guldberg et al., 2018). The ecosystem services from corals have been valued in the billions of dollars and mainly include nutrient cycling, food supply, shoreline protection, erosion regulation, a source of income by boosting fishery and tourism industries (Hoegh-Guldberg et al., 2018). Coral reefs directly support over 500 million people worldwide, mostly in developing countries (IUCN 2017). India is blessed with four major coral reefs in the Gulf of Kachchh, Lakshadweep archipelago, Gulf of Mannar, and the Andaman and Nicobar Islands. Apart from these reefs, there are several small reefs are there like Netrani Island in Karnataka coast (Zacharia et al., 2008), Grande Islands in Goa coast (Rodriques,1998), Gavesani bank in off Malpe, Kerala coast (Nair, 1978) and the Malvan Marine Sanctuary (MMS) along the Maharashtra coast. Biodiversity and ecological studies from these reefs, especially the Malvan and Goa, are poorly described. The MMS is the only Marine Protected Area (MPA) in the Central West Coast of India and harbours coral reef ecosystem. The MMS is spread over 29.12 km2 with a core zone of 3.182 km2, and the buffer zone is comprising of an area of 25.94 km2 between 160 02’00 N-16003’90 N and 73025’00 E-73029’25E. Submerged and exposed rocks protect corals from strong wave action and endow with ideal substratum for coral settlement. Most of the coral species have grown in patches on the subtidal reef flat. The MMS significantly contributes to the livelihood of the local fishermen population. Apart from the marine fishery, eco-tourism is the fastest growing economic sector associated with coral reefs in this region. However, due to the lack of a management plan and opposition of the local community, the MMS is not operational MPA in the real sense (Rajagopalan, 2008). Despite the presence of coral reef in the MMS, very little is known so far on coral reef ecology, health status, i.e., coral disease, bleaching, and influence of different environmental drivers on the reef ecosystem. Therefore, a detailed study on reef biodiversity, the extent of the reef formation, the health status of reef-forming corals, and the impact of coastal pressure and changing climatic vii conditions is carried out through this Ph.D. research work. The present thesis forms a comprehensive study on the biodiversity of scleractinian corals and associated biota, ecology, and present health status of the coral reefs in the MMS. Objectives: The following objectives were set for doctoral work: To document the distribution and abundance of corals and associated biota. To study the seasonal variation in coral-associated species composition. To assess the response of selected species to anthropogenic factors. Structure of the thesis The thesis is presented in the following eleven chapters: Chapter-1: This chapter provides a general introduction to the thesis and comprises the rationale of the scientific problem. Chapter-2: This chapter includes a literature review on coral reef research in India. Wherein I reviewed the documented scleractinian fauna from the Indian water and presented a revised checklist and biogeography of scleractinian from the major Indian reefs. Chapter-3: This chapter describes details of geomorphology, environmental setup, reef biodiversity, and economic status of the Malvan region on the Central West Coast of India. Chapter-4: This chapter describes the distribution and abundance of corals of the MMS reefs. The detailed taxonomic identification, distribution, and photographic illustration of the coral species described in this chapter. Chapter-5 This chapter investigates the distribution and abundance of coral reef-associated fishes. Chapter-6: This chapter illustrates seasonal variation (pre-monsoon and post-monsoon) in coral reef-associated macroalgal and algal turfs abundance. Chapter-7: This chapter assesses the seasonal variation (pre-monsoon and post-monsoon) in coral- boring sponges.