south bay salt pond restoration-- challenges to ecological restoration

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Goals of the Restoration Project Restore and enhance a mix of wetland habitats Provide for flood management Provide for public access and recreational opportunities

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South Bay Salt Pond Restoration-- Challenges to Ecological Restoration Topics Covered in this Talk Goals of the Project & Scientific Input Restore to What? Key Habitats in the Restoration Plan Constraints on Restoration Success Some Key Questions Moving forward in the face of Uncertainty Goals of the Restoration Project Restore and enhance a mix of wetland habitats Provide for flood management Provide for public access and recreational opportunities Scientific Direction is Needed To identify ecologically meaningful restoration goals To identify and evaluate uncertainties, constraints and complications To identify ways to reach ecological restoration goals in light of these challenges Restore to What? What is the Goal? Native, indigenous ecosystem as a goal Improving ecological functioning as a goal Historical view helps guide restoration goals Current conditions guide restoration goals San Francisco Bay Habitats ca (SFEI EcoAtlas Project) Our Urbanized Estuary Oakland HarborCarquinez Straights Conversion to Salt Ponds A Mix of Habitats for a Diversity of Species Habitat Mix Restore Vegetated Tidal Salt Marsh Manage Ponds of Various Salinities Maintain Ecological Functions of Mudflat and Slough Habitats outside Ponds How do we restore tidal salt marsh and manage salt ponds while maintaining the ecological support provided by habitats outside the ponds? Three Conceptual Models Tidal Salt Marsh Managed Pond Landscape Level bay, mudflats, sloughs Factors that Limit Full Ecological Restoration Scientific Constraints: Data on sediment loads, sea-level rise Technical Constraints: Engineering limitations Human Impacts: Adjacent land uses, flooding, mosquitoes Regulatory Requirements: Water quality, species Economic Constraints: Costs of different actions Scientific Constraints Missing data on current conditions critical to restoration of the target habitat Lack of data on short-term ecological processes (acting immediately after restoration actions initiated) Inability to predict long-term ecological processes (acting long after restoration is initiated) Goals of Restoration Science Identify the conditions and processes most important to successful restoration Collect data on essential conditions and processes, where possible Estimate range of uncertainty produced by not having all necessary data Sediment Loads Invasive Species Sea-level Rise Pond Elevations Pollutant Effects Landscape Change Current Conditions Short-term Conditions Restoration Actions Long-term Conditions Adaptive Management Tidal Marsh Restoration: Actions, Conditions, Constraints Collect Data Collect Data Potential Constraints on Successful Salt Marsh Restoration Levee heights/adjacent land uses Inadequate sediment supplies Sea-level rise Non-native invasive species Pollutant impacts Importance of particular ponds Potential Constraints on Pond Management Ability to maintain salinities at suitable levels for target species Ability to maintain levees and structures Smell associated with algal decay Importance of particular ponds for tidal marsh restoration Potential Impacts of Restoration on South Bay Waters, Mudflats, Sloughs Localized salinity changes due to pond water release Regional loss of mudflat due to sediment sinks in ponds being restored to salt marsh Local loss of slough habitat from scour due to changes in water circulation Some Key Questions Sediments To what extent is the suspended sediment supply adequate for restoration? How might sediment needs of restoring pond affect sloughs and mudflats in the Bay? Some Key Questions Non-native Species Can we prevent non-native, species, esp. Spartina alterniflora and predators, from dominating restored marshes? What ecological effects are likely from particular non-native species? Are there design alternatives, e.g., levee design, breach location, etc., that can be incorporated to prevent the access of non-native species into restored wetlands? Some Key Questions Habitats and Species What ecosystem functions are provided by the existing habitats and habitats planned for restoration? Can remaining ponds be managed to increase their shorebird and waterfowl carrying capacity? What physical factors drive the conversion of one habitat type to another? Are there any critical factors that may limit ecosystem development Some Key Questions Pollutants To what extent might restoration activities release contaminants, especially mercury? What are the ecological effects of released contaminants? What is the potential for nuisance algal blooms in future managed ponds? Dealing with Uncertainty Analyze existing data Collect additional data in the short-term Model ecological processes Assess uncertainty (modeling, stats) Conduct long-term monitoring Conduct new research Moving Forward with Restoration Use the best existing data Collect more data during planning Implement the most scientifically-sound plan Use adaptive management to learn & improve