.................................................................................................................................... ii Acknowledgements ................................................................................................................. iv Preface ....................................................................................................................................... v Abbreviations .......................................................................................................................... vi Table of contents .................................................................................................................. viii List of Figures ......................................................................................................................... xii List of Tables .......................................................................................................................... xv General Introduction ............................................................................................................... 1 Chapter 1: Literature Review ............................................................................................ 5 1.1. Global and regional elasmobranch biodiversity ....................................................... 5 1.2. Status of exploitation and implications for ecosystems ............................................ 7 1.3. Different fisheries and their impacts .......................................................................... 9 1.4. Current status of elasmobranch management in South Africa ............................. 14 1.5. Historical and contemporary gene flow patterns in elasmobranchs ..................... 15 1.6. Study species (Galeorhinus galeus Linnaeus 1758) ................................................. 21 1.7. Study species (Carcharhinus brachyurus Günther 1870) ....................................... 24 1.8. Study species (Rhinobatos annulatus Müller & Henle 1841) ................................. 26 1.9. Study Aims .................................................................................................................. 27 Chapter 2: Optimizing microsatellite multiplex panels and their utility in South Africa’s commercially exploited and endemic elasmobranchs .......................................... 29 Abstract ................................................................................................................................... 29 2.