Transcript Slide 1
Modeling the impact of future climate change on salmon habitat restoration actions James Battin Mark Scheuerell Krista Bartz Hiroo Imaki Mary Ruckelshaus Matthew Wiley Elizabeth Korb Richard Palmer Northwest Fisheries Science Center UW Civil & Environmental Engineering Snohomish River Basin Habitat Destruction & Degradation Habitat Destruction ( Capacity) • Riparian forest clearing • Channelization Habitat Degradation ( Survival) • Increased water temperature • Larger floods • Increased sedimentation 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 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 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 Life-cycle model Harvest effects Hydropower effects SHIRAZ Climate 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 100 2 Egg to fry survival (%) R = 0.95 80 60 40 20 0 0 20 40 Fine sediment (%) 60 80 Action Class Variables Modeling Salmon Population Response to Restoration: SHIRAZ Riparian Forest Artificial Barriers Off-channel Habitat Edge Habitat Habitat Structures Fine Sediment SHIRAZ Inputs Temperature Forest Cover SHIRAZ Outputs Capacity at Stage s+1 (cs+1) Survival from Stage s→s+1 (ps→s+1) Abundance at Stage s+1 (Ns+1) Abundance at Stage s (Ns) Impervious Surface Road Density Peak Flow Events Functional relationships in SHIRAZ Incubation temperature (egg-to-fry survival) Pre-spawning temperature Freshwater habitat (spawner-to-egg survival) Fine sediment (egg-to-fry survival) Peak Flow (egg-to-migrant survival) Biological response SHIRAZ is a life-cycle model estimating cumulative effects of suites of actions Egg stream gradient stream width riparian condition Fry temperature Smolt Adult peak flows sediment temperature channel structure edge habitat estuary connectivity Results of the sensitivity analyses Percent increase in spawners 45 historical juvenile capacity historical spawner capacity 40 fry-smolt s +10% 35 egg-fry s +10% 30 25 20 15 10 5 0 Entire basin Estuary Mainstem Lowland Location of restoration action Headwaters Evaluation of Restoration Scenarios Three scenarios: 1) Historical: Pre-European settlement 2) Current Path: Extrapolation of land use change 3) Restoration Percent of Historical SHIRAZ Results: Spawner Abundance 100% Target 80% 60% Snoqualmie Skykomish 40% 20% 0% Historical Current Path Restoration Historical Summarizing spatial structure No spawning <500 spawners 500-1000 spawners >1000 spawners Current path Restoration Assumptions of First Round of SHIRAZ Modeling • Static climate conditions • Linear projection of land use change How robust are proposed restoration actions to violations of these assumptions? 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 Modeled Climate Effects on Salmon Climate Change Increased Water Temperature Incubation Temp Prespawning Temp Survival Altered Stream Flow Incubation Flow Spawning Capacity Capacity (Ad. & Juv.) Juvenile Capacity? 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 Future Scenarios for the Snohomish • Climate --no warming --moderate warming --extreme warming Future Scenarios for the Snohomish • Climate --no warming --moderate warming --extreme warming • Restoration --Historical conditions --Current path --Restoration plan (Alt. 3) 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 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? 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 Predicted Atmospheric CO2 Climate Model (GCM) Air Temp., Meteorology Hydrology Model (DHSVM) Land Cover & Land Form Maps Stream flow, Temp. Salmon Pop. Model (SHIRAZ) Salmon Population Forecast Model Modifications • Make Land Use Change Targets (including Restoration and Current Path) Spatially Explicit Alternative Land Use Scenarios 2001 Alternative Land Use Scenarios Current Path 2001 2025 Alternative Land Use Scenarios Current Path Restoration 2001 2025 Model Modifications • Make Land Use Change Targets Spatial • Make Model Stochastic (i.e., like a PVA) Model Modifications • Make Land Use Change Targets Spatial • Make Model Stochastic • Develop interface with stochastic DHSVM hydrology model 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 Climate Effects: Current Path Percent of Current Path 160% 140% 120% 100% 80% 60% 40% 20% 0% Baseline Temp + 2 Temp + 4 Flow + 20% Flow + 40% Interaction of Restoration and Climate Percent of Current Path 250% 200% 150% Current Path Restoration 100% 50% 0% Baseline Temp +4 Flow +40% Historical Summarizing spatial structure No spawning <500 spawners 500-1000 spawners >1000 spawners Current path Restoration XX X XX X Future Directions • More mechanistic/realistic projections of land use change --collaborate with land use modelers Future Directions • More mechanistic/realistic projections of land use change --collaborate with land use modelers • Interactions between hatchery and wild fish --competition, straying, genetics 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 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? Collaborators University of Washington NOAA Fisheries School of Aquatic & Fish. Sci. Ray Hilborn Mary Ruckelshaus Krista Bartz Mark Scheuerell Hiroo Imaki Kerry Lagueux JISAO Nate Mantua Dept. of Civil & Env. Engin. Rick Palmer Matt Wiley Liz Korb Andre Ball [email protected]