COASTAL IMPOUNDMENT DECISION MAKING ADAPTATION IN ACTION

1. COASTAL IMPOUNDMENT DECISION MAKING ADAPTATION IN ACTION Rob Hossler and Karen Bennett – Delaware Div. Fish & Wildlife Austin Kane - National Wildlife Federation

2. LIONS, TIGERS and On The GROUND CLIMATE CHANGE ADAPTATION…OH MY! Delaware’s Efforts to get over the Fear and Make Decisions to Implement/Adapt to Climate Change for its Coastal Impoundments

3. Coastal Impoundments History Salt hay farming Rice production Mosquito control Waterfowl habitat

5. Today…Multiple Functions for Wildlife: • Breeding habitat for shorebirds, rails, bitterns, waterfowl • Feeding habitat for migrating shorebirds, waterfowl, post-breeding wading birds • Roosting habitat for shorebirds, waterfowl • Fish nursery habitat • Muskrat habitat

6. Today…Multiple Socioeconomic Functions: • Waterfowl hunting • Birding, wildlife viewing, photography • Furbearer trapping • Flood-hazard reduction • Mosquito control

7. Coastal Impoundments in DE: • State maintains 14 coastal impoundments comprising 2,400 acres on several state wildlife areas along the central to southern Delaware Bay coast, and a few along the Atlantic Coast. • USFWS maintains 1,100 acres at Bombay Hook NWR and 4,200 acres at Prime Hook NWR, both along Delaware Bay coast.

8. Urgency to Do Adaptation Thrust Upon Us Breaches 2010 Breaches 2012 Impoundment Wetland Habitat at risk Impoundment wetlands converting to open water. Prime Hook NWR – after Hurricane Sandy 2012. Prime Hook NWR – after 2009 Mother’s Day storm.

11. STATE IMPOUNDMENTS ARE NOT IMMUNE! Breach of State Impoundment Dikes after Hurricane Irene (2011)

12. Step 1: Initiation of a State Impoundment Management Plan/Philosophy • Collective wisdom of administrator, program and land managers, and staff scientists to support continued management and preservation of state impoundments. • Goal is to Avoided Administrative Neglect, i.e., “I will be retired before it’s an issue” and make adaptation an immediate priority among other current funding needs. • Begin the development of a systematic approach for evaluating the current status of impoundments, identifying objectives and developing an adaptive strategy to enhance resilience in face of climate change.

13. Multiple OBJECTIVES: • Maximize Juvenile Fish Populations • Maintain Furbearer populations at a desired level (e.g., Muskrat) • Minimize Mosquito Production • Maximize Recreational Use • Minimize Cost • Maximize Breeding Marsh Birds • Maximize Roosting Red Knots and Spring Migrating Shorebirds • Maximize Breeding Shorebirds (e.g., Black-necked Stilt) • Maximize Migrating and Wintering Waterfowl • Maximize Fall Migrating Shorebirds • Maximize Breeding Waterfowl

14. Now what??? It’s complicated…. • We can’t manage for everything, everywhere…not physically possible given biological needs of target wildlife. • We’ll never have all the data we think we need. • Cost constraints and uncertainty are a reality. • Tradeoffs among competing objectives must be made. • We want to find the best combination of management actions to achieve multiple affordable objectives in the face of climate change uncertainty.

15. Step 2: Approach - Structured Decision Making • Developed a prototype decision model for 4 impoundments looking 30 years out (estimated impoundment life span). • Small team of experts identified key management objectives and predicted outcomes (e.g., duck-use days, roosting red knots, mosquito and fish counts) of different actions under different SLR scenarios (5 and 10 mm/year). • SDM is an explicit, organized way to deal with multiple, competing objectives and uncertainty. • Flexible • Transparent • Adaptive • Incorporates cost constraints • Provides a suite of actions that maximizes benefit

16. GOAL: If we are spending the time and money on these impoundments we need to maximize their functions in an explicit, organized way that deals with multiple, competing management objectives and cost constraints under the uncertainty of SLR. • Coordinated water-level management (% of full pool) across a suite of impoundments to provide for: • Vegetation growth (waterfowl) • Exposed mudflat (shorebirds) • Pools and channels (fish and mosquitos)

18. Influences – Consequences Diagram Rectangles = management decision nodes; ovals = stochastic process nodes; rounded rectangles = intermediate calculations; and hexagons = outcomes (e.g., objectives).

19. Utility Functions for Objectives These objectives were than weighted for Relative Importance. Example - Red Knots = 0.31 Waterfowl = 0.38 Fish = 0.17 Mosquito = 0.14

20. LONG-TERM ACTIONS UNDER SLR UNCERTAINTY: • Water management regime? • Repair levees and water-control structures? • Raise elevation with thin-layer application of dredge material? • Create salt marsh buffers? • Build new impoundments in uplands? • Abandon and restore to tidal salt marsh habitat?

21. Consequences – Predictions and Uncertainty Uncertainty Uncertainty

22. How Do We Decide? • Each action has an expected benefit. • Benefit is determined by: • Species response • Uncertainty • Species weighting • Each action has a cost.

23. Using Excel “Solver” Add-in:

24. Step 3: Pilot Habitat Projects • Select “no regret” restoration projects anticipated to have success to restore wetland habitat and enhance impoundment resiliency to climate change. • These project fall in three categories: • Better Management Practices • Resiliency in the Form of Structure Integrity (improvements or buffers). • Strategic Retreat.

25. Better Management Practices • Better Data Collection: Vegetation Transects, Integrated Waterbird Management and Monitoring (“IWMM”), Hydrology and Hydraulic studies. • Are we achieving what we want – qualitatively and quantitatively? • Provides baseline for monitoring of pilot projects, SLR scenarios and evaluating management practices.

26. Buffer Construction Restore old levee Create tidal marsh within 106-acre containment cell, eventually with tidal exchange via channel creation. Reinforce existing dikes

27. Strategic Retreat • Wildlife Conservation Society-funded project working with The National Wildlife Federation. • Inland retreat of a 389-acre impoundment where we have lost some of our management capabilities to maximize functions and values. • Creates an 86-acre impoundment complex from an existing pond and two agricultural fields augmented with freshwater to maximizes functions and values and replace larger impoundment.

28. Thank you!!! • National Fish and Wildlife Foundation • Wildlife Conservation Society • State Wildlife Grants and Wildlife and Sport Fish Restoration • National Wildlife Federation – Climate Smart Guidance Project • Delaware Impoundment Management and SDM Team