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Closing the Loop: Environmental Variability Throughout the Life-cycle of Oregon Coastal Natural Coho Salmon. Pete Lawson, Libby Logerwell, Nate Mantua, Bob Francis, and Vera Agostini. OCN Oregon Coastal Natural Coho salmon Aggregate of 13 basins Rain-fed streams
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Closing the Loop: Environmental Variability Throughout the Life-cycle of Oregon Coastal Natural Coho Salmon Pete Lawson, Libby Logerwell, Nate Mantua, Bob Francis, and Vera Agostini
OCN • Oregon Coastal Natural • Coho salmon • Aggregate of 13 basins • Rain-fed streams • Threatened status (on and off) D Air Temperature Data O Streamflow Data
The OCN Problem: OCN Recruits (t+1) and Spawners (t-2)
Model of Marine Survival based on Ocean Environment Logerwell, Mantua. Lawson, Francis, Agostini (in press)
Marine Factors Predicting Survival:First Winter SST, Spring Upwelling, Spring Transition, Second Winter SST
OCN smolts and smolts/spawner Reconstructed from OPIH- and GAM-estimated marine survivals.1992 estimate omitted from analysis.
Environmentaldata sets -- freshwater • 1969-1999 smolt year • Stream Flow • From 6 USGS gauging stations • Monthly mean flow • Standardized at each station, then averaged • Air Temperature • From 3 WRCC locations • Annual mean air temperature • Standardized at each station, then averaged
Coho Salmon Life Cycle with Putative Freshwater Environmental Factors
Freshwater Factors Predicting OCN smolts Annual Temperature Fall Transition Winter Flow (t1) Spring Flow (t1)
So why should we believe this? Because I repeated the analysis with a completely independent data set from the Queets River, Washington. • One basin • Glacier-fed • 1981-2000 smolt years • Smolts and spawners measured directly • No dams • Flow data from USGS -- one station • Air temperature data from WRCC -- one station
Freshwater Factors Predicting Queets Smolts Winter Flow (t1) Annual Temperature
Coho Salmon Life-cycle with Freshwater and Marine Environmental Factors
The Bottom Line:Marine and freshwater environmental variables are correlated so that good (poor) marine survival is associated with good (poor) freshwater production. Marine Marine Freshwater
Combining Freshwater and Marine Models R2 = 0.118 P = 0.041 R2 = 0.632 P < 2E-7 R2 = 0.575 P < 1E-6
Questions: Biology • What are the mechanisms of temperature and flow effects? • Timing – life-cycle stage • Scale – area of operation • How does freshwater habitat affect the response? • Logging, agriculture, urban development • Restoration
Questions: Climate • What is an efficient index of climate conditions that includes both freshwater and marine variability? • How can we use these models to project likely futures for coho salmon? • GCMs
Spawners Early * Late * fecundity OO OO ++ ++ Eggs Metapopulation Dynamics Population Dynamics Harvest Management Freshwater Habitat Marine Survival Climate Patterns
Peter LawsonNMFS/NWFSC2030 SE Marine Science DriveNewport, OR 97365541-867-0430peter.w.lawson@noaa.gov