Climate Adaptation in the Delaware Estuary: Risks, Opportunities and Tough Choices

1. Climate Adaptation in the Delaware Estuary: Risks, Opportunities and Tough Choices Danielle KreegerScience Director

3. ID Vulnerabilities Loss of Nature’s Benefits Tidal Marshes Bivalve Shellfish Adaptation Options Recommendations Drinking Water Case Studies Climate Ready Pilot Adaptation Planning DK 3

4. Climate Change in the Delaware Estuary Temp Salinity Sea Level Rise Storms Water Wetlands Fish & Wildlife • Likely Physical Changes 2. Example Effects on Key Resources DK 4

5. Climate Impacts on Drinking Water Supply Prototype Examples

6. Prototype • Drinking Water Tough Questions • How can we maintain low salinity in the • upper estuary? • Will more reservoirs be needed, which have • their own issues? • Where should infrastructure be protected • from SLR versus strategic retreat? Examples

7. Tidal Wetlands A Signature Trait of System Near Contiguous Band Diverse: Freshwater Tidal Marshes Brackish Marshes Salt Marshes Nature’s Benefits Flood Protection Water Quality Fish and Wildlife Natural Areas Carbon Sequestration

8. Wetland Benefits (Ecosystem Services) Livelihoods Health Health Lives Health Health Health

9. Living Shorelines 2008 Tidal Wetlands Long-standing Concerns Degradation Conversion and Loss Growing Concerns Sea Level & Salinity Rise Storms Sediment budget DK 9

10. Smooth Response Example Abrupt Response Likely Ecosystem Response Ecosystem Response Threshold Extent of Climate Change Extent of Climate Change Are Coastal Wetlands Crossing a Tipping Point? Critical thresholds can be breached even if conditions change gradually Unlikely Slide adapted from Carlos Duarte DK 10

11. Angola Neck – Rehoboth Bay, DE Summer, 2006 Sudden Wetland Dieback – Marsh Browning Slide from Chris Bason and Amy Jacobs

12. Changes in Wetland FunctionNatural versus Restored Reference Wetland Condition Existing Wetlands Benefits(functions) Restored Wetlands time Slide adapted from Amy Jacobs (DNREC)

13. Tidal Wetland Vulnerability? Freshwater Tidal Marshes • Salinity Rise Causes Conversion to Brackish • Barriers to Landward Migration • Others: Tidal Range, Seasonal Drying/Wetting Salt Marshes • Sea Level Rise, Subsidence and Sediment Deficits Lead to Drowning • Storms and Wind Wave Erosion • Barriers to Landward Migration • Others: Seasonal Wetting/Drying, Invasives

14. Options? Living Shorelines

15. Delaware Estuary Living Shorelines

16. Tidal Wetlands Adaptation PlanningGoal: Maximize long-term health and resiliency • Wetland Tough Choices • Where will wetlands will be • converted to open water? • Where can we save them ? • Where is strategic retreat • the best option? DK 16

17. 11 Other Species of Freshwater Unionid Mussels Corbicula fluminea Elliptio complanata Rangia cuneata Mya arenaria Geukensia demissa Mytilus edulis Ensis directus Mercenaria mercenaria Crassostrea virginica Bivalves of the Delaware DRBC DK 17

19. Patchy, Impaired Rare Extirpated Strophitus undulatus Elliptio complanata Alasmidonta heterodon Shifts in Species Ranges of Freshwater Mussels     

20. Salt Line Location Oyster Disease and Salinity From Rutgers HSRL From DRBC www.livingclassrooms.org/lbo/dermo/oyster2.jpg

21. No Help With Help Oyster ManagementCan they maintain (or be maintained) until they might see more optimal conditions? DK 21 Longer Growing Season Options? Shellplanting 2 Recruitment Events Intertidal Niche Expansion? Point of No Return Today 2030 2060 Historical data from Rutgers Haskin Shellfish Laboratory

22. Brandywine River, PA Elliptio complanata Delaware Estuary Marshes Geukensia demissa Delaware Bay Oysters Crassostrea virginica Brandywine River, PA DK 22

23. Bivalve Vulnerability? Oyster Reefs • Salinity Driven Disease Epizootics • Others: Food, pH Salt marsh Mussel Beds • Loss and Degradation of Wetland Habitat • Others: Food, PH Freshwater Mussel Beds • Range Shifts with No Dispersal • Habitat Degradation (T, salinity, pH, fish hosts)

24. Nature’s Benefits Bivalve Shellfish are “Ecosystem Engineers” CTUIR Freshwater Mussel Project DK 24

25. Water Filtration Benefits Start No mussels 8 adult mussels Slide from R. Neves, VA Tech DK 25

26. Water Filtration Benefits Later No mussels 8 adult mussels Slide from R. Neves, VA Tech DK 26

27. Water Filtration Benefits

28. Nature’s Benefits (Natural Capital) Shellfish Tough Decisions Which species and associated benefits can be sustained? Which should we invest in? (since funding will always be limited) Livelihoods Lives Health Livelihoods Health

29. Climate Change in a Complex Landscape The Living Estuary Water fowl, finfish, shellfish Horseshoe crab population Extensive tidal marshesThe Working River 4th largest USurban center world’s largest freshwater port 70% of east coast oil past and present industrial center DK 29

30. Climate Change +Other Changes DK 30 • Ecological Flows • Marcellus Shale • Spills, NRDA • Dredging Added Complexity • Withdrawals • Wind Farms • Land Use Change • Development • Emerging Pollutants

31. “Restore” for the Future • Forecast future sustainable states (winners and losers) • Smart “restoration” = climate adaptation • Shift policy and management paradigms Maximize Bang for the Buck Today 2030 DK 31

32. - End -

33. Next Steps? 1. ScienceStrengthen adaptation plan with more rigorous monitoring and predictive modeling for likely consequences 2. Local Relevance Develop high resolution geospatial–based planning tools that guide local actions, nested within a watershed-basis 3. Nature’s Benefits Develop and use decision tools with “bang for the buck” estimates of environmental outcomes for various adaptation tactics 4. Collaboration Implement a coordinated strategy for advancing science, policy and on-the-ground actions

34. Many Other Issues Timing of Shorebird Migration and Horseshoe Crab Spawning Website slides are from the Delaware Shorebird Project and the Horseshoe Crab Conservation Network