Modeling the impact of future climate change on salmon habitat restoration actions

1. Modeling the impact of future climate change on salmon habitat restoration actions James BattinMark ScheuerellKrista BartzHiroo ImakiMary RuckelshausMatthew WileyElizabeth KorbRichard Palmer Northwest Fisheries Science Center UW Civil & Environmental Engineering

2. Snohomish River Basin

3. Habitat Destruction & Degradation • Habitat Destruction (¯ Capacity) • Riparian forest clearing • ChannelizationHabitat Degradation (¯ Survival) • Increased water temperature • Larger floods • Increased sedimentation

4. Proposed Habitat Restoration Actions • Restore instream habitat --Riparian restoration --Habitat reconnection --Instream habitat restoration • Restore hydrologic processes --Land use modification --Floodplain restoration --Road removal • Overall goal: increase salmon population size to some target level

5. Modeling Salmon Population Responses to Restoration • SHIRAz • Relates changes in environment to changes in salmon population size via: --Capacity --Survival • Process-based • Spatially explicit • Stage-structured

6. Climate Life-cycle model Conceptual Foundation • Life-cycle model is at the core • Changes to the “H’s” alter habitats, ecological interactions, and population dynamics Landscape processes Land use Habitat effects Hatchery effects Harvest effects Hydropower effects SHIRAZ

7. Assessing habitat conditions and landscape processes for life-cycle modeling • Instream habitat conditions available from field inventories, gages, and models • Land cover information from inventories and GIS-based modeling • Fish data from TRTs • Fish-habitat relationships from literature

8. Riparian Forest Artificial Barriers Off-channel Habitat Habitat Structures Impervious Surface Forest Cover Temperature Peak Flow Events Survival from Stage s→s+1 (ps→s+1) Abundance at Stage s+1 (Ns+1) Modeling Salmon Population Response to Restoration: SHIRAZ Action Class Variables Edge Habitat Road Density Fine Sediment SHIRAZ Inputs Capacity at Stage s+1 (cs+1) Abundance at Stage s (Ns) SHIRAZ Outputs

9. Functional relationships in SHIRAZ Incubation temperature (egg-to-fry survival) Freshwater habitat Pre-spawning temperature (spawner-to-egg survival) Fine sediment (egg-to-fry survival) Biological response Peak Flow (egg-to-migrant survival)

10. Egg Fry Smolt Adult SHIRAZ is a life-cycle model estimating cumulative effects of suites of actions peak flows sediment temperature stream gradient stream width riparian condition channel structure edge habitat estuary connectivity temperature

11. Results of the sensitivity analyses

12. Evaluation of Restoration Scenarios Three scenarios:1) Historical: Pre-European settlement2) Current Path: Extrapolation of land use change3) Restoration

13. SHIRAZ Results: Spawner Abundance Target Percent of Historical

14. Historical Summarizing spatial structure No spawning <500 spawners 500-1000 spawners >1000 spawners Current path Restoration

15. Assumptions of First Round of SHIRAZ Modeling • Static climate conditions • Linear projection of land use changeHow robust are proposed restoration actions to violations of these assumptions?

16. Climate Change Over Next 50 Years in the Northwest • Warmer air temps  warmer water temps • Earlier snowmelt  earlier (more intense?) flooding, lower summer flows • Altered precipitation regime (maybe wetter)  increased flood magnitude • Altered ocean conditions (possibly warmer)  decreased ocean survival

17. Increased Water Temperature Altered Stream Flow Incubation Temp PrespawningTemp IncubationFlow ­ Capacity (Ad. & Juv.) Survival ¯ SpawningCapacity ¯ JuvenileCapacity? Modeled Climate Effects on Salmon Climate Change

18. Scenario Planning • Uncertainty high, change uncontrollable • Evaluate several plausible alternative futures (bracket extremes) • Assess how robust recovery actions are to alternative future change (land use and climate) scenarios

19. Future Scenarios for the Snohomish • Climate --no warming --moderate warming --extreme warming

20. Future Scenarios for the Snohomish • Climate --no warming --moderate warming --extreme warming • Restoration --Historical conditions --Current path --Restoration plan (Alt. 3)

21. Future Scenarios for the Snohomish • Climate --no warming --moderate warming --extreme warming • Restoration --Historical conditions --Current path --Restoration plan (Alt. 3) • Land Use --Current Path --High growth --Low growth --Different policy assumptions

22. Changes to Modeling Framework • Q: How do we translate future climate and land use scenarios into variables SHIRAZ can use? e.g., how will climate change affect peak winter flows?

23. Changes to Modeling Framework • Q: How do we translate future climate and land use scenarios into variables SHIRAZ can use? e.g., how will climate change affect peak winter flows? • A: Interface with DHSVM stream flow model

24. Climate Model (GCM) Predicted AtmosphericCO2 Air Temp., Meteorology Hydrology Model (DHSVM) Land Cover & Land Form Maps Stream flow, Temp. Salmon Pop. Model (SHIRAZ) Salmon Population Forecast

25. Model Modifications • Make Land Use Change Targets (including Restoration and Current Path) Spatially Explicit

26. Alternative Land Use Scenarios 2001

27. Alternative Land Use Scenarios Current Path 2001 2025

28. Alternative Land Use Scenarios Current Path Restoration 2001 2025

29. Model Modifications • Make Land Use Change Targets Spatial • Make Model Stochastic (i.e., like a PVA)

30. Model Modifications • Make Land Use Change Targets Spatial • Make Model Stochastic • Develop interface with stochastic DHSVM hydrology model

31. Some Simple, Preliminary Model Perturbations • CLIMATE CHANGE • Pre-spawning temperature change: -- + 2 degrees C -- + 4 degrees C • Incubation period flows: -- + 20% -- + 40%RESTORATION • Increased juvenile rearing capacity

32. Climate Effects: Current Path Percent of Current Path

33. Percent of Current Path Interaction of Restoration and Climate

34. No spawning <500 spawners 500-1000 spawners >1000 spawners X X X X X X Historical Summarizing spatial structure Current path Restoration

35. Future Directions • More mechanistic/realistic projections of land use change --collaborate with land use modelers

36. Future Directions • More mechanistic/realistic projections of land use change --collaborate with land use modelers • Interactions between hatchery and wild fish --competition, straying, genetics

37. Future Directions • More mechanistic/realistic projections of land use change --collaborate with land use modelers • Interactions between hatchery and wild fish --competition, straying, genetics • Climate (change) effects on ocean survival --correlated or uncorrelated with freshwater

38. Future Directions • More mechanistic/realistic projections of land use change --collaborate with land use modelers • Interactions between hatchery and wild fish --competition, straying, genetics • Climate (change) effects on ocean survival --correlated or uncorrelated with freshwater • Plasticity in life histories of wild fish --how might fish adapt to change? --how will climate/land use change affect the distribution of life history types?

39. Collaborators University of Washington NOAA Fisheries School of Aquatic & Fish. Sci. Mary RuckelshausRay Hilborn Krista Bartz Mark ScheuerellJISAO Hiroo ImakiNate Mantua Kerry LagueuxDept. of Civil & Env. Engin.Rick PalmerMatt WileyLiz KorbAndre Ball james.battin@noaa.gov