Issues in measuring and managing changes to the ecological character of the Western Port Ramsar Site as a result of climate change

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1 presenter: Shelley Heron Issues in measuring and managing changes to the ecological character of the Western Port Ramsar Site as a result of climate change

2 Western Port Bay Where is it? Ecological character description Threats Climate change risks Action Knowledge gaps Presenting a case study with issues that are relevant to estuaries world wide.

3 Western Port Bay Australia, Victoria South eastern Australia 60 km south Melbourne

4 Western Port Bay 60,000 ha (148,000 acres) Different habitat types Mudflats - mangroves, sea grass beds Salt marsh Sandy beaches, rocky shores Deep channels Listed on Convention on Wetlands of International Importance in 1982 (Ramsar Convention)

5 Areas surrounding Western Port are used for agriculture, some are urbanised, some has been reclaimed for sporting fields, ringed by public land and the majority of the catchment is in private ownership Industry Deep shipping channels Mudflats Fishing Shallow channels Mangroves

6 Ramsar Wetland Meets 7 Ramsar Criteria natural or near-natural wetland type vulnerable, endangered, or critically endangered plants and animals important for maintaining the biological diversity plant and animal species at a critical stage in their life cycles, or provides refuge during adverse conditions. regularly supports 20,000 or more waterbirds regularly supports 1 per cent of the individuals in a population of one species or subspecies of waterbird important source of food for fishes, spawning ground, nursery and migration path for fish Photo: Danny Rogers

7 Ecological Character Description Melbourne environment team of KBR was commissioned to prepare the Ecological Character Description by the Department of Environment Water Heritage & the Arts. Photo: Danny Rogers

8 Ecological Character Description describes essential elements, components, processes, benefits and services sets a benchmark from which change can be measured describes threats to the ecological character describes the current status and any evident change within the site describes knowledge gaps and monitoring requirements Photo: Danny Rogers

9 Ecological Character Description describes essential elements, components, processes, benefits and services sets a benchmark from which change can be measured describes threats to the ecological character describes the current status and any evident within the site describes knowledge gaps and monitoring requirements Photo: Danny Rogers

10 Threats to ecological character Historical site and catchment alterations Catchment and coastal erosion Climate change Deteriorating water quality Shipping Recreational activities Pest plants and animals Urban development Grazing Recreational and commercial fishing Impacts Erosion Channelisation enhanced sediment delivery Sediment input Elevated turbidity levels and poor water quality Loss of seagrass beds Pollution from a variety of sources Dredging leading to increased sediment input Disturbance to waterbirds Uncontrolled vehicle access causing damage to intertidal mudflats Encroachment of exotic flora and loss of habitat Increased competition with native flora and fauna Predation of native fauna species Degradation to intertidal areas and native vegetation Sea level rise and storm surges leading to increased inundation, habitat loss and erosion Elevated sea water temperatures altering marine habitat Reductions in rainfall causing fluctuations in water quality of catchment inflows Increased run-off and stormwater May be exacerbated with changing climate

11 Summary of estimated future changes in climate for the Western Port region Increase in annual average temperatures Lower rainfall in catchment More frequent intense rainfall events Increased frequency of droughts Decrease in annual average relative humidity Frequency of weather conditions conducive to high forest fire risk will increase Increased sea levels Increased storm surge heights Increased frequency of 1:100 yr storm tide heights Increased areas of inundation Sourced from CSIRO various publications

12 Some implications for Western Port Bay s Ecological Character Intertidal mudflats that are currently exposed at low tide may be permanently inundated or exposed less frequently Storm surges may exacerbate coastal erosion and sediment delivery that can impact distribution of mangroves, seagrass & saltmarsh communities Storm events may cause further catchment erosion & sediment delivery which can impact seagrass distribution

13 Direct impacts on ecological character & Ramsar criteria Change to habitats may cause impacts on several of the Ramsar criteria

14 Ramsar resolution Contracting Parties recognise that climate change may substantially affect the ecological character of wetlands and their sustainable use In 2002 at the 8 th meeting of the of the Conference of the Contracting Parties Resolution VIII.3: Climate change and wetlands: impacts, adaptation, and mitigation was adopted. Asked Contracting Parties to manage wetlands to increase their resilience to climate change and extreme climatic events. SO WHAT IS BEING DONE TO MAKE WESTERN PORT MORE RESILIENT?

15 Action - Legislation 3 Marine National Parks Federal Legislation that controls infrastructure development with specific reference to Matters of National Environmental Significance (EPBC Act) State Legislation that controls infrastructure development that may impact Ramsar wetlands (Environment Effects Act) State Legislation to protect listed significant species (FFG Act) Local Planning legislation that controls development through Planning Schemes, zones and permits

16 Action- catchment projects Waterway stabilisation and revegetation to reduce sediment loads Improving environmental flows in waterways Reducing nutrients in waterways (phosphorus & nitrogen) Implemented through Catchment Management Authority LandCare groups Other government agencies & volunteer organisations

17 Action catchment projects Bunyip River Fishway Galaxias Fish migration between fresh & saline habitats Bed and bank stabilisation Habitat complexity Tupong

18 Action restoration projects School Engagement Program - engage schools in growing and planting mangrove seedlings Western Port DVD Project - produced and are distributing a DVD with the aim of building public awareness and knowledge of special features and threatening processes to Western Port. Seagrass Restoration Project the first full scale seagrass transplanting experiment to be undertaken in Western Port. Improving Water Quality - the project aimed to improve water quality by planting mangroves to reduce coastal erosion. Implemented through Catchment Management Authority Western Port Seagrass Partnership

19 Action - research CSIRO still undertaking climate change modelling through the Future Coasts Program Modeling suitable areas for re-establishment of managrove and saltmarsh communities given a rise in sea level exploring two variables: tidal regime wave energy Climate change impacts on Victoria s coastal vegetation (mangroves and saltmarsh): Western Port Case Study Professor Paul Boon, Victoria University, Australia Dr Steve Sinclair & Dr Matt White, Arthur Rylah Institute, Australia Abstract: Practical Responses to Climate Change National Conference, Melbourne 2010.

20 Lots of great work to promote resilience Legislation in place to manage future development Catchment and restoration projects to remediate problems of the past Some research Fantastic projects being undertaken by lots of groups Benchmark to measure change via the ECD

21 Challenges Improving resilience is only part of the solution Planning and development decisions of the past remain Little room for migration of existing habitats mudflats, mangroves, saltmarsh & studies just beginning

22 Knowledge gaps Better understanding potential loss of habitat as a result of sea level rise, changes to the tidal regime and increasing temperatures and the response of flora & fauna to these changes Better understanding of severity of coastal erosion and sedimentation resulting from climate change, including sea level rise and storm surges Understand water quality changes in association with reduced catchment inflows resulting from climate change Appropriateness of past development & infrastructure decisions and plan for the future How will communities adapt?

23 Western Port acts as a good case study and could be anywhere in the world. Similar threats, impacts, risk of climate change, challenges & knowledge gaps. As estuary managers, planners, policy makers we are grappling with many unknowns of climate change. While we do this making estuaries and their catchments more resilient is good practice. Photo: Danny Rogers