v Government of Western Australia Department of the Premier and Cabinet Perth and Peel Green Growth Plan for 3.5 million Strategic Assessment of the Perth and Peel Regions Draft EPBC Act Strategic Impact Assessment Report Appendix%3BNTBS$POEJUJPO4UBUFNFOUT December 2015 Acknowledgements This document has been prepared by Eco Logical Australia Pty Ltd and © Government of Western Australia Open Lines Consulting. Department of the Premier and Cabinet Disclaimer Dumas House This document may only be used for the purpose for which it was 2 Havelock Street commissioned and in accordance with the contract between Eco Logical Australia Pty Ltd and the Department of the Premier and West Perth WA 6005 Cabinet. The scope of services was defined in consultation with the Department of the Premier and Cabinet, by time and budgetary Website: www.dpc.wa.gov.au/greengrowthplan constraints imposed by the client, and the availability of reports Email: [email protected] and other data on the subject area. Changes to available information, legislation and schedules are made on an ongoing Tel: 08 6552 5151 basis and readers should obtain up to date information. Fax: 08 6552 5001 Eco Logical Australia Pty Ltd accepts no liability or responsibility Published December 2015 whatsoever for or in respect of any use of or reliance upon this report and its supporting material by any third party. Information provided is not intended to be a substitute for site specific assessment or legal advice in relation to any matter. Unauthorised use of this report in any form is prohibited. Strategic Assessment for the Perth and Peel Regions CONDITION STATEMENT – BECHER POINT RAMSAR SITE EXECUTIVE SUMMARY The Becher Point Wetlands Ramsar site is located 9 km south of the City of Rockingham and 50km south of Perth within the Swan Coastal Bioregion of Western Australia and covers 677 hectares, of which less than 10% is wetland area (Figure D1). The Becher Point Wetlands Ramsar site is part of the Port Kennedy Scientific Park (Nature Reserve 44077). Excluding a small section in the southwest, the reserve is vested in the Conservation Commission for the purpose of ‘Conservation of Flora and Fauna’ and is administered under the Department of Parks and Wildlife as part of the Rockingham Lakes Regional Park. The Becher Point wetlands are a series of wetlands formed in the linear depressions (beach ridges) between the parallel sand ridges, termed dunal swales.– these wetlands become progressively younger towards the coastline forming a geological progression of the progradation process. Today, the wetlands are different ages and are at different stages of initiation and development. These wetlands stand as a record of a generally uninterrupted and progressive wetland initiation over a period of 5,000 years. The Becher Point Wetlands Ramsar site covers only a proportion of the Becher cuspate foreland, encompassing approximately 60 of the 300 Becher Suite wetland basins and 2 of 3 Cooloongup Suite wetlands that were originally mapped in 1986-88. The Becher Point Wetlands Ramsar site was designated on 5 January 2001 as meeting two of the nine listing criteria as it represents an example of shrub swamps and seasonal marshes in a near natural condition and a rare example of a geomorphological sequence of Holocene wetlands containing a sedgelands community (Threatened Ecological Community), being particularly important for demonstrating a continuous depositional history of sediment during the last 3,000 years. Although the Ramsar site is primarily reserved for nature conservation purposes, passive recreation that does not impact on natural values or ecosystems of the reserve is permitted. The greatest threats to the values of the lakes from visitor access are from uncontrolled and unauthorised access by four- wheel drive vehicles. These activities cause trampling of plants, spread weeds and disease, disturbs native fauna, including roosting shorebirds and soil compaction and erosion. The Ramsar site is largely fenced, but the gate is constantly broken by members of the community to allow vehicle access. The site is accessible via entry along the beach. Re-evaluation of the Becher Point Wetlands Ramsar site for the drafting of the Ecological Character Description (ECD-2007) and in 2011 for the Commonwealth’s Rolling Review of Ramsar sites in Australia, confirmed the criteria for listing the system remain and while significant pressures were recognised and gaps in knowledge and monitoring existed, the site retained the biotic components and ecological processes that were the basis for recognising the site as a wetland of international significance. The evaluation conducted in this condition report is the most extensive conducted since the publication of the 2007 ECD. 2 Strategic Assessment for the Perth and Peel Regions Serious threats exist at the Ramsar site, the most significant being fire frequency which combined with declining groundwater levels in the northern and eastern sectors of the site and continued access by off-road vehicles has led to weed invasions along the access tracks and in cases these have spread to significant areas, particularly in the northern and eastern sectors, closest to urban infrastructure. Beach erosion has removed one occurrence of the TEC (BP1) in the last 5 years and sea level rise will likely become the most significant threat in future years. Groundwater levels are generally stable, although levels in wetlands closest to urban infrastructure have declined in recent years. It is unclear whether this can be attributed to a reduction in rainfall, groundwater abstraction or potentially both. Importantly, the annual monitoring of the Threatened Ecological Community (TEC) vegetation condition has not indicated any alteration by the by the recent decline in groundwater levels. The site would benefit from having a dedicated monitoring program designed to facilitate reporting on the condition of the site’s key values, including the nationally listed TEC and the processes that maintain these values and the expression of water in the interdunal swales. The Department of Water is currently reviewing the adequacy of the existing groundwater monitoring program and licensed groundwater use in this locality as part of implementing the Rockingham – Stakehill groundwater management plan 2008. Particular regard will be given to further examining the local hydrological processes in order to maintain adequate water levels at the Becher wetlands Ramsar site. Elsewhere in the site, groundwater levels remain static. Nutrient loads are within eutrophic levels as a result of nutrient leakage within the catchment, but is not resulting in algal growth within the wetlands. The pH and conductivity are within acceptable limits and not identified as threats. Monitoring of vegetation in wetlands is limited to the north-east of the Becher Point Wetlands Ramsar site closest to the Port Kennedy golf course and a strategic vegetation monitoring program is required, particularly to better delineate the TEC and wetland vegetation and changes in extent and condition that may occur through future pressures from climate change and urban pressures. 3 Strategic Assessment for the Perth and Peel Regions 1 Introduction 1.1 INTRODUCTION TO THIS REPORT The purpose of this technical report is to provide a Condition Statement for the Becher Point Wetlands Ramsar site. It will be used to inform the development of Draft Commonwealth Impact Assessment Report (CIAR) and the Draft Strategic Conservation Plan for the Strategic Assessment of the Perth and Peel Regions (SAPPR). This report has been developed collaboratively by a number of Western Australian State Government Agencies, as the technical experts regarding the Ramsar site. Agencies authors include: Department of Water. Department of Parks and Wildlife. Department of Premier and Cabinet. The content of this report is based on: Information Sheet on Ramsar Wetlands (RIS)-updated November 2014. Ecological Character Description for the Becher Point Wetlands Ramsar site (Draft V & C Semeniuk Research Group 2007) (ECD). 1.2 BECHER POINT WETLANDS RAMSAR SITE OVERVIEW The Becher Point Wetlands Ramsar site was listed as a Wetland of International Importance under the Ramsar Convention in January 2001. The Ramsar site comprises a portion of the system of interdunal wetlands on the beachridge plain which forms the geomorphic surface of the Becher cuspate foreland, on the coast of south-west Western Australia. The series of wetlands within the Ramsar site exhibits a continuum of development in geomorphology, sedimentary fill, hydrology, hydrochemistry and vegetation, and is considered by researchers to be a unique wetland system in Western Australia and one of the youngest wetland systems on the Swan Coastal Plain. The sedgelands that occur within the linear wetland depressions of the Ramsar site are a nationally listed Threatened Ecological Community (TEC) under the Australian Government Environment Protection and Biodiversity Conservation Act (1999). The community is recorded as ‘Sedgelands in Holocene dune swales of the southern Swan Coastal Plain’ and is listed as endangered (Figure D1). Historically, as the cuspate foreland prograded seawards, a series of beach ridges were progressively produced and a chain of wetlands formed in the linear depressions between the parallel sand ridges – these wetlands become progressively younger towards the coastline. Today, the wetlands are different ages and are at different stages of initiation