ECOLOGICAL CHARACTER DESCRIPTION OF THE LAKE GORE RAMSAR SITE, ESPERANCE, WESTERN AUSTRALIA A report by the Department of Environment and Conservation Ecological Character Description of the Lake Gore Ramsar Site Acknowledgements Funding for the development of this document was sourced jointly from the Natural Heritage Trust (NHT) and the State and Commonwealth contributions to the National Action Plan for Salinity and Water Quality (NAP). NHT and NAP are jointly administered by the Australian Government departments of Agriculture, Fisheries and Forestry and the Environment, Water, Heritage and the Arts and the WA Natural Resource Management Office. In-kind contributions were gratefully received from the organisations represented on the Technical Advisory Group. Document Preparation This document has been prepared by the Wetlands Section of the Department of Environment and Conservation. Gareth Watkins - Author / conceptual models and graphics Jennifer Higbid - Internal review Expert Advice Steve Appleyard DEC Roger Jaensch Wetlands International Tilo Massenbauer DEC John Simons DAFWA Doug Watkins Wetlands International Technical Advisory Group Members Michael Coote DEC Robyn Cail South Coast NRM Ian Hartley Esperance Regional Forum Jennifer Higbid DEC Tegan Laslett DEC John Lizamore DEC Julie Patten DEC Ken Read Esperance Bird Observers Group John Simons DAFWA Thank you to the following people for their contributions Margaret Brock University of New England David Cale DEC Tracy Calvert DoW _________________________________________________________________________ I Ecological Character Description of the Lake Gore Ramsar Site Nikki Cowcher DEC Henry Dabb South Coast NRM Brad Degans DoW Paul Galloway DAFWA Jennifer Hale Aquatic Ecologist Stuart Halse Bennelongia Geraldine Janicke University of Western Australia Steve Janicke Jim Lane DEC Adam Lillicrap DAFWA Cliff Lloyd DEC Malcolm Robb DoW Marcus Singor Birds Australia Richard Sutton DAFWA Ryan Vogwill DEC David Weaver DAFWA Yvonne Winchcombe DEC Stephen Wong DEC Katherine Zdunic DEC Photo credits Cover photograph: Lake Gore (G. Watkins) Internal photographs: B. Cook, G. Janicke, G. Watkins. Other credits Symbols in conceptual models courtesy of the Integration and Application Network <http://ian.umces.edu/symbols/ >, University of Maryland Center for Environmental Science To reference this document Department of Environment and Conservation (2009). Ecological Character Description of the Lake Gore Ramsar Site: A Report by the Department of Environment and Conservation . Prepared by G.Watkins, Department of Environment and Conservation, Perth, Western Australia. _________________________________________________________________________ II Ecological Character Description of the Lake Gore Ramsar Site TABLE OF CONTENTS GLOSSARY ...........................................................................................................IX ABBREVIATIONS................................................................................................XIII EXECUTIVE SUMMARY..................................................................................... XIV 1.0 INTRODUCTION............................................................................................... 1 1.1 SITE DETAILS......................................................................................................... 2 1.2 PURPOSE OF AN ECOLOGICAL CHARACTER DESCRIPTION .......................... 3 1.2.1 OBJECTIVES OF THE LAKE GORE RAMSAR SITE ECOLOGICAL CHARACTER DESCRIPTION ...................................................................................................................... 5 1.3 RELEVANT TREATIES, LEGISLATION AND REGULATIONS .............................. 7 1.3.1 INTERNATIONAL AGREEMENTS/CONVENTIONS ..................................................... 7 1.3.2 NATIONAL LEGISLATION ........................................................................................... 8 1.3.3 WESTERN AUSTRALIA STATE LEGISLATION .......................................................... 9 2.0 DESCRIPTION OF THE LAKE GORE RAMSAR SITE.................................. 11 2.1 LOCATION ............................................................................................................ 11 2.2 LAND TENURE AND LAND USE.......................................................................... 11 2.3 CULTURAL HERITAGE ........................................................................................ 12 2.3.1 ABORIGINAL HERITAGE ...........................................................................................12 2.3.2 EUROPEAN HERITAGE .............................................................................................12 2.4 CLIMATE............................................................................................................... 12 2.5 WETLAND TYPES ................................................................................................ 16 2.6 RAMSAR CRITERIA ............................................................................................. 18 2.6.1 RAMSAR CRITERIA UNDER WHICH THE SITE WAS DESIGNATED ........................18 2.6.2 CURRENT RAMSAR CRITERIA .................................................................................20 2.6.2.1 ASSESSMENT AGAINST EACH OF THE RAMSAR CRITERIA FOR THE LAKE GORE RAMSAR SITE ..................................................................................................................................23 3.0 LAKE GORE RAMSAR SITE: CRITICAL ECOSYSTEM COMPONENTS, PROCESSES, BENEFITS AND SERVICES......................................................... 26 3.1 CRITICAL ECOSYSTEM COMPONENTS AND PROCESSES ............................. 26 3.1.1 GEOMORPHOLOGY ...................................................................................................30 3.1.2 HYDROLOGY ..............................................................................................................32 3.1.3 WATER QUALITY .......................................................................................................41 3.1.3.1 LAKE GORE WATER PHYSICO -CHEMICAL PROPERTIES .................................................42 3.1.3.2 CATCHMENT SURFACE AND GROUND WATER PHYSICO-CHEMICAL PROPERTIES ..............48 3.1.4 PHYSICAL PROCESSES ............................................................................................51 3.1.5 WETLAND SOILS .......................................................................................................52 3.1.6 BIOTA .........................................................................................................................55 3.1.6.1 WATERBIRDS ..........................................................................................................55 3.1.6.2 FISH ......................................................................................................................66 3.1.6.3 AQUATIC INVERTEBRATES ........................................................................................67 3.1.6.4 VEGETATION ...........................................................................................................70 3.2 CRITICAL ECOSYSTEM BENEFITS AND SERVICES ......................................... 75 3.2.1 PROVISIONING SERVICES ........................................................................................79 _________________________________________________________________________ III Ecological Character Description of the Lake Gore Ramsar Site 3.2.2 REGULATING SERVICES ..........................................................................................79 3.2.3 CULTURAL SERVICES ...............................................................................................80 3.2.4 SUPPORTING SERVICES ..........................................................................................81 4.0 THREATS TO ECOLOGICAL CHARACTER ................................................. 83 4.1 AGRICULTURAL ACTIVITIES .............................................................................. 85 4.1.1 ALTERED HYDROLOGY ............................................................................................85 4.1.2 POLLUTION ................................................................................................................88 4.1.3 ALTERED FIRE REGIMES ..........................................................................................89 4.2 NON-NATIVE AND ALIEN SPECIES .................................................................... 90 4.3 CLIMATE CHANGE............................................................................................... 91 4.4 RECREATION ....................................................................................................... 92 5.0 CHANGES TO ECOLOGICAL CHARACTER ................................................ 93 5.1 INTERACTION BETWEEN THE CRITICAL ECOSYSTEM COMPONENTS, PROCESSES, BENEFITS, SERVICES AND THREATS ............................................. 94 5.2 CHANGES TO CRITICAL ECOSYSTEM COMPONENTS AND PROCESSES..... 96 5.3 CHANGES TO CRITICAL ECOSYSTEM BENEFITS AND SERVICES................. 97 6.0 LIMITS OF ACCEPTABLE CHANGE............................................................. 99 7.0 KNOWLEDGE GAPS.................................................................................... 108 8.0 MONITORING REQUIREMENTS ................................................................. 112 9.0 COMMUNICATION, EDUCATION AND PUBLIC AWARENESS................. 117 REFERENCES...................................................................................................