MINISTRY OF EDUCATION AND TRAINING NHA TRANG UNIVERSITY NGUYEN Y VANG EFFECTS OF CHANGES IN SEA SURFACE TEMPERATURE ON MIGRATORY SPANISH MACKEREL OF THE COASTAL CURRENT IN NHA TRANG BAY, 1996 – 2015 MASTER THESIS NHA TRANG - 2017 MINISTRY OF EDUCATION AND TRAINING NHA TRANG UNIVERSITY NGUYEN Y VANG EFFECTS OF CHANGES IN SEA SURFACE TEMPERATURE ON MIGRATORY SPANISH MACKEREL OF THE COASTAL CURRENT IN NHA TRANG BAY, 1996 – 2015 MASTER THESIS Major: Marine Ecosytem Management Change Topic Allocation Decision Decision on establishing the Committee: 3rd June 2017 Defense date: Suppervisors: NGUYEN THI KIM ANH HENRIK GLENNER SIGURD STEFANS Chairman: LE KIM LONG Faculty of Graduate Student QUACH HOAI NAM NHA TRANG - 2017 and based Climate UNDERTAKING I undertake that the thesis entitled: “Effects of changes in Sea Surface Temperature on migratory Spanish mackerel of the coastal current in Nha Trang Bay, 1996 – 2015” is my own work The work has not been presented elsewhere for assessment until the time this thesis is submitted Khanh Hoa, 28th June 2017 Author Nguyen Y Vang i ACKNOWLEDGMENT The author acknowledges supporting from the Norwegian Agency for Development Cooperation (NORAD) for the NORHED Master's Program in Marine Ecosystem Management and Climate Change I acknowledge funding from the Norwegian Agency for Development Cooperation (NORAD) for my scholarship to follow this master's program I would like to express the deepest appreciation to the Faculty of graduate students of Nha Trang University for helping and giving best conditions as well as scholarship to finish my thesis My special thanks go to Prof Nguyen Thi Kim Anh, Prof Henrik Glenner, Prof Sigurd Stefansson and Prof Audrey Geffen for the continuous support of my study and research, for their patience, motivation, enthusiasm, and immense knowledge Their guidance helped me in all the time of research and writing of this thesis I deeply thank the Fishing Cooperative Bich Hai and Vietnam National Centre for Hydrometeorological Forecasting and RDA (http://dss.ucar.edu) for their offers in collecting data We are thankful to Mr Huan in using of MapInfo Professional Software to figure the map of study area Our gratitude is also extended to Mr Tan, leader of Bich Hai set-net fihsery for assisting with data collection without their substantial cooperation and assistance this paper would not have been successful Last but not least, I would like to thank my family: my parents and to my brothers and sister for supporting me spiritually throughout writing this thesis Thank you! Khanh Hoa, 28th June 2017 Author Nguyen Y Vang ii TABLE OF CONTENTS UNDERTAKING i ACKNOWLEDGMENT ii LIST OF SYMBOLS v LIST OF ABBREVIATIONS vi LIST OF TABLES vii LIST OF FIGURES AND GRAPHS viii ABSTRACT xi CHAPTER INTRODUCTION CHAPTER LITERATURE REVIEW CHAPTER RESEARCH METHODOLOGY 16 3.2 Data collection 17 3.2.1 Secondary data 17 3.2.2 Primary data 18 3.2.3 Data analysis 19 CHAPTER RESULTS AND DISCUSSIONS 22 4.1 RESULTS 22 4.1.1 Variability of SST during period of 1996 – 2015 22 4.1.2 Changes in landings of Bich Hai Set-net fishery during 1996 to 2015 24 a Fluctuation in annual landings 24 b Inter-annual fluctuations in average landings calculated for fishing months 25 4.1.3 Variations in weight individual of Mackerel during study period 27 a Fluctuations in annual average weight individual 27 b Occurrence of several individual sizes in weight in the catches 29 iii 4.1.4 Correlation between SST and landings of Spanish Mackerel 30 a Between SST and landings based on annual calculation 30 b Between SST and Landings calculated for several months 31 4.1.5 Effect of changes in SST on Spanish Mackerel body-sizes 33 a Effect of changes in inter-annual average SST on average individual weight 33 c Effects of changes in annual average SST on different mackerel body sizes 34 4.2 DISCUSSIONS 36 CHAPTER CONCLUSIONS AND RECOMMENDATIONS 43 4.1 CONCLUSIONS 43 4.2 RECOMMENDATIONS 43 REFERENCES 45 APPENDICES 50 iv LIST OF SYMBOLS r: coefficient of correlation Pearson p-value: Probability value (