A Biophysical Assessment of the Philippine Territory of the Sulu-Sulawesi Marine Ecoregion Sulu-Sulawesi Marine Ecoregion Program WWF-Philippines May 2003 CREDITS AUTHORS: Angel Alcala, Ph.D. Monyeen Alava, M.Sc. Emmanuel Anglo, Ph.D. Naniel Aragones, Ph.D. Emmanuel Bate, M.Sc. Flordeliz Guarin, Ph.D. Rudolf Hermes, Ph.D. Daniel Lagunzad, Ph.D. Augustus Rex Montebon, M.Sc. Ramon Miclat Jose Angelito Palma Johanna Pe-Montebon Hildie Maria Nacorda, M.Sc. Teresita Perez, Ph.D. Gavino Trono, Jr., Ph.D. Arnel Andrew Yaptinchay, D.V.M. EDITORS: Johanna Pe-Montebon, Evangeline F.B. Miclat, M.Sc., and Jose Noel Dumaup TECHNICAL ASSISTANTS: Josephine Sumangil-Evangelista and Dino Leoncarlo Calderon INTEGRATOR: Johanna Pe-Montebon TECHNICAL ADVISERS/REVIEWERS: Alan White, Ph.D., Angel Alcala, Ph.D., and Romeo Trono ACKNOWLEDGEMENT: The Biophysical Assessment of the Sulu-Sulawesi Marine Ecoregion is funded by WWF-US. 1 TABLE OF CONTENTS Credits............................................................................................................................. 1 Table of Contents....................................................................................................... 2 List of Figures ............................................................................................................. 5 List of Tables ............................................................................................................... 7 List of Appendices ..................................................................................................... 9 Chapter I Introduction THE ECOREGION CONSERVATION CONCEPT....................................................................... 10 OBJECTIVES OF THE BIO-PHYSICAL ASSESSMENT……………………………………..….11 METHODOLOGY ................................................................................................................. 12 Chapter II The Physical Setting within Sulu-Sulawesi GEOGRAPHIC COVERAGE AND GEOMORPHOLOGY ............................................................. 13 The Marine Environments of Sulu-Sulawesi........................................................ 13 The Philippine Inland Seas ................................................................................... 14 The Sulu Sea ......................................................................................................... 17 The Sulu Archipelago-Zamboanga Peninsula ...................................................... 19 Sulawesi Sea ......................................................................................................... 22 GEOLOGY........................................................................................................................... 23 Tectonic Setting and Geologic History................................................................. 23 Active Geologic Processes.................................................................................... 28 METEOROLOGY.................................................................................................................. 32 Climatic Controls.................................................................................................. 32 Monthly Station Weather...................................................................................... 38 OCEANOGRAPHY................................................................................................................ 47 Bathymetry of Major Basins................................................................................. 47 Tides...................................................................................................................... 48 Currents................................................................................................................. 49 Wind-Generated Waves........................................................................................ 53 Sea Surface Temperature (SST)............................................................................ 54 Storm Surges......................................................................................................... 61 WATER QUALITY ............................................................................................................... 62 Riparian Ecosystems............................................................................................. 62 Estuarine and Associated Ecosystems .................................................................. 73 Coastal and Marine Ecosystems ........................................................................... 75 Effects on Primary Production.............................................................................. 79 2 Chapter III The Watersheds and their Linkages to the Ecoregion THE WATERSHED DEFINED................................................................................................ 81 LOCATION, OCCURRENCE AND DISTRIBUTION................................................................... 81 THREATS TO WATERSHED AREAS...................................................................................... 85 Agriculture and aquaculture.................................................................................. 86 Legislation and Resource Management................................................................ 87 Chapter IV Coastal and Marine Ecosystems and their Associated Species I. THE MANGROVE ECOSYSTEM........................................................................................ 88 Coverage, Occurrence and Distribution................................................................ 88 Species diversity ................................................................................................... 88 Importance ............................................................................................................ 96 Threats .................................................................................................................. 98 Resource Management.......................................................................................... 99 II. THE SEAWEED AND SEAGRASS ECOSYSTEMS............................................................. 101 Occurrence, Distribution and Data Gaps ............................................................ 101 Importance .......................................................................................................... 104 Threats and Resource Management Issues ......................................................... 105 III. THE CORAL REEF ECOSYSTEM.................................................................................. 105 Distribution of Noteworthy Reef Areas and Species Diversity.......................... 105 Importance .......................................................................................................... 124 Threats and Issues............................................................................................... 126 Resource Management........................................................................................ 127 IV. THE SOFT BOTTOM ECOSYSTEM............................................................................... 131 Benthic Faunal Assemblages .............................................................................. 131 Importance .......................................................................................................... 131 Threats ................................................................................................................ 132 V. MARINE PLANKTON AND ECOSYSTEM LINKAGES ...................................................... 133 Dynamics and Linkages...................................................................................... 134 Importance .......................................................................................................... 136 Threats ................................................................................................................ 137 VI. MARINE FISHERY RESOURCES OF NERITIC ECOSYSTEMS ......................................... 144 Major Fishing Grounds within SSME ................................................................ 144 Major Fishery Resources of the Region.............................................................. 145 Importance .......................................................................................................... 157 Threats ................................................................................................................ 161 Resource Management........................................................................................ 162 Chapter V Species of Special Concern BACKGROUND.................................................................................................................. 164 MARINE BIRDS................................................................................................................. 164 3 Occurrence and Distribution............................................................................... 164 Threats ................................................................................................................ 167 Conservation Initiatives ...................................................................................... 167 MARINE MAMMALS ......................................................................................................... 167 Dugongs .............................................................................................................