EAST AFRICAN COMMUNITY LAKE VICTORIA BASIN COMMISSION East African Community, Lake Victoria Basin Commission, Off Kenyatta Highway, LAKE VICTORIA BASIN ECOSYSTEM New Nyanza Regional Headquarters, PROFILE ASSESSMENT REPORT 13th Floor, P.O BOX 1510-40100, Kisumu, Kenya LAKE VICTORIA BASIN ECOSYSTEM PROFILE ASSESSMENT REPORT | FEBRUARY 2016 ASSESSMENT REPORT PROFILE BASIN ECOSYSTEM VICTORIA LAKE FEBRUARY 2016 170 LAKE VICTORIA BASIN ECOSYSTEM PROFILE ASSESSMENT REPORT LAKE VICTORIA BASIN ECOSYSTEM PROFILE ASSESSMENT REPORT FEBRUARY, 2016 DISCLAIMER The views expressed in this publication do not necessarily reflect the views of the United States Agency for International Development or the United States Government. FEBRUARY 2016 i ACKNOWLEDGEMENTS The Lake Victoria Basin Commission wishes to thank all those who participated in the preparation of the Lake Victoria Basin Ecosystem Profile Assessment (EPA) Report. The team worked with policymakers and practitioners from a wide range of sectors and disciplines, including government and nongovernment stakeholders, the private sector, and communities, all of whom contributed with thoughtfulness to this highly commendable cause-conserving biodiversity in the Lake Victoria Basin. Special thanks go to our colleagues in the Planning for Resilience in East Africa through Policy, Adaptation, Research and Economic Development Project: U.S. Agency for International Development/Kenya and East Africa Regional Mission, Tetra Tech, Land Trees and Sustainability Africa, the EPA consultants, and all members of the Biodiversity Task Force of the East African Community. The report was prepared by Tetra Tech and Land Trees and Sustainability (LTS) Africa Tetra Tech 159 Bank Street, Suite 300 Burlington, Vermont 05401 USA Telephone: (802) 495-0282 Fax: (802) 658-4247 E-Mail: [email protected] LTS Africa Ltd, Lavington Shopping Complex, PO Box 25496-00603, Nairobi, Kenya Telephone: +254 735 780 973 Email: [email protected] Website: www.ltsi.co.uk COVER PHOTO: Mara River and swamp, as viewed from the Kirumi Bridge, courtesy of PREPARED Project Unless otherwise stated, the maps, photos, and illustrations used in this report were obtained from the original sources cited in the accompanying text. Photos from the BSAs in Section 6 were obtained from the PREPARED Project unless cited otherwise. ii LAKE VICTORIA BASIN ECOSYSTEM PROFILE ASSESSMENT REPORT TABLE OF CONTENTS LIST OF TABLES ................................................................................................................................................................................................................................. v LIST OF FIGURES ............................................................................................................................................................................................................................... vii ACRONYMS AND ABBREVIATIONS .................................................................................................................................................................................. ix EXECUTIVE SUMMARY ................................................................................................................................................................................................................ xii 1.0 OVERVIEW OF THE ECOSYSTEM PROFILE ASSESSMENT PROCESS ..............1 1.1 INTRODUCTION ........................................................................................................................................................................ 1 1.1.1 PREPARED Project.....................................................................................................................................................1 1.1.2 EPA Purpose...................................................................................................................................................................1 1.2 EPA APPROACH .......................................................................................................................................................................... 2 1.2.1 Best Practices..................................................................................................................................................................2 1.2.2 Key Concepts.................................................................................................................................................................4 1.3 THE LVB EPA PROCESS .......................................................................................................................................................... 4 1.3.1 Governance.....................................................................................................................................................................5 1.3.2 Data Collection and Analysis.................................................................................................................................5 1.3.3 Stakeholder Engagement.........................................................................................................................................6 1.3.4 Validation of the EPA Report...............................................................................................................................6 1.4 BSA SELECTION PROCESS................................................................................................................................................... 7 1.4.1 Selection Criteria ....................................................................................................................................................7 1.4.2 Two-tiered Approximation ..................................................................................................................................9 2.0 THE BIODIVERSITY CONSERVATION CONTEXT IN THE LVB............................16 2.1 THE PHYSICAL ENVIRONMENT ...................................................................................................................................... 1 6 2.1.1 Location..............................................................................................................................................................................16 2.1.2 Topography and Geology........................................................................................................................................16 2.1.3 Surface Hydrology........................................................................................................................................................17 2.1.4 Sub-basin Flows..............................................................................................................................................................19 2.1.5 Groundwater Hydrology..........................................................................................................................................23 2.1.6 Surface Water Quality...............................................................................................................................................24 2.1.7 Ecological Changes in Lake Victoria...................................................................................................................25 2.1.8 Factors Causing Ecological Change.....................................................................................................................25 2.1.9 Rivers....................................................................................................................................................................................27 2.1.10 Water Balance................................................................................................................................................................28 2.1.11 Wetlands...........................................................................................................................................................................29 2.1.12 Environmental Flows..................................................................................................................................................29 2.2 CLIMATE OF THE LVB ............................................................................................................................................................. 35 2.3 THE BIOLOGICAL ENVIRONMENT .............................................................................................................................. 3 6 2.3.1 Terrestrial Biodiversity...............................................................................................................................................36 2.3.2 Freshwater Biodiversity.............................................................................................................................................39 2.4 SOCIO-ECONOMIC CONTEXT ...................................................................................................................................... 40 2.4.1 Importance of Ecosystem Services in Partner States...............................................................................40 2.4.2 Livelihoods and Biodiversity Linkages ...............................................................................................................42 2.4.3 Biodiversity and Gender............................................................................................................................................46