1. Some potential impacts of climate change and altered runoff regimes on riverine ecosystems Tim Beechie (NOAA) Bob Naiman (UW) Coastal Rivers Research Consortium

2. Hydrologic regime and salmon life history diversity in Puget Sound Questions: Can environmental indicators help identify How life history diversity of an ESU has changed? Which populations are important for recovery? Beechie, T., E. Buhle, M. Ruckelshaus, and A. Fullerton Submitted to Biological Conservation

3. The basic approach Select environmental indicators that exert long- term selective pressure on populations Correlate indicators with life history traits Map the ‘environment’ and populations Examine changes to life history diversity and potential for recovery

4. Data sets Runoff patterns USGS mean monthly discharge Temperatures unavailable Life history traits Percent yearling smolts Mean spawn date Mean spawner age Mean length (4 yrs)

5. Mapping hydrologic regimes Cluster analysis identifies three hydrologic regimes Snowmelt Transitional Rainfall J O DNJASMJMAF

6. Mapping hydrologic regimes Classification tree identifies elevation and precipitation zones for each hydrologic regime

7. Mapping hydrologic regimes Calculate mean elevation and precipitation for all 30- m grid cells Rainfall Transition Snowmelt

8. Hydrologic regime and life history diversity

9. Conclusion 1 Populations with high proportions the stream type life history rare Those populations are clustered in a small geographic area

10. Hydrologic regime and life history diversity

11. Conclusion 2 Historical stream-type fish extirpated by dams blocking access to snowmelt habitats May be recoverable; life histories less genetically distinct in Puget Sound

12. Some general questions 1. What are habitat consequences of shifting runoff regimes? 2. Can species adapt quickly enough? 3. Are there other factors that might ameliorate climate change effects?

13. April 1 SWE (mm) Current Climate“2020s” (+1.7 C)“2040s” (+ 2.5 C) -44%-58% Dire predictions Courtesy Alan Hamlet, UW Climate Impacts group

14. Mote P.W.,Hamlet A.F., Clark M.P., Lettenmaier D.P., 2005, Declining mountain snowpack in western North America, BAMS (in press) But haven’t we seen this already? 1950 1997

15. Runoff regimes are shifting: Spring runoff will be less and earlier Catherine Creek, Union, OR

16. Runoff regimes are shifting: Spring runoff will be less and earlier Catherine Creek, Union, OR 1920s - July

17. Runoff regimes are shifting: Spring runoff will be less and earlier Catherine Creek, Union, OR Current, normal year - June

18. Runoff regimes are shifting: Spring runoff will be less and earlier Catherine Creek, Union, OR Future - May

19. Some potential habitat consequences Increased winter incubation temperature Stream-type chinook salmon Less water in spring Cottonwood seedling establishment Steelhead spawning Increased summer stream temperature All stream-type salmon

20. Can species adapt quickly enough? Three key questions: Is timing of life history events genetically controlled? If no, higher likelihood of viable populations If yes: How fast is habitat changing? How fast can species adapt?

21. Critical life history events for Cottonwood Seed dispersal between late April and July Seedlings die when root growth (½ inch per day) is slower than water table recession Seeds only viable for 6 to 8 weeks after dispersal

22. Critical life history events for Steelhead Migration between July and March Spawning between March and May Egg incubation between April and Early July

23. Potential consequences of changes in runoff regime Cottonwood Seed dispersal timing may adjust? Little chance of seedling survival if hydrograph becomes rainfall-dominated? Steelhead Spawning timing may adjust to timing of spring melt? Less chance of survival if hydrograph becomes rainfall-dominated?

24. How can we test these ‘hypotheses’? Snowpack and hydrology have already changed 50% less in many areas Find locations with altered runoff regime Can we see evidence of effects on cottonwood or steelhead? Cottonwood establishment history in ‘control’ and ‘treatment’ sites Extensive post-treatment inventory of steelhead spawning and juvenile survival

25. April 1 SWE (mm) Current Climate“2020s” (+1.7 C)“2040s” (+ 2.5 C) -44%-58% Finding sensitive sites Courtesy Alan Hamlet, UW Climate Impacts group

26. What data can we collect? Cottonwood Establishment history in sensitive drainages Age trees along the drainage length and across drainages Expect recent cohorts in snowmelt systems Expect older cohorts in streams that have shifted to rainfall Steelhead Population trends in sensitive drainages Spawner history Reports of extirpated runs Expect steep decline or extirpation in streams that have shifted to rainfall

27. Are there other factors that can ameliorate climate change effects? Restoration of incised channels Rebuild large aquifers Decrease stream temperatures

28. Are there other factors that can ameliorate climate change effects? Riparian restoration Decrease stream temperatures