Slide show given at the CA NV Amphibian Population Task Force Meeting in Yosemite, Jan. 7, 2011

1. The Perils of Unpalatable Periphyton ! Sarah J. Kupferberg UC Berkeley, Int. Biology Amy J. Lind USFS, Pacific Southwest Research Station, Davis, CA Acknowledgments California Energy Commission San Francisco Public Utilities Commission Paula Furey, diatom expert Cheryl Bondi, algae collection

2. Sarah J. Kupferberg UC Berkeley, Int. Biology Amy J. Lind USFS, Pacific Southwest Research Station, Davis, CA Acknowledgments California Energy Commission San Francisco Public Utilities Commission Paula Furey, diatom i.d. Cheryl Bondi, algae collection Wendy Palen, population modeling Feeding Ecology of Larval Foothill Yellow-legged Frogs ( Rana boylii ) in regulated rivers

4. Multiple Stressors Contribute to Pattern

5. Indirect Effects Changes physical habitat, riparian veg., predator assemblage Direct Effects of Dams Barriers to movement, gene flow Mortality from ill timed releases and periphyton for my tadpoles

6. Spring Early Summer Late Summer Early Fall Frog life stages in synchrony with algal succession

7. Epithemia Rhopalodia Cladophora with heavy epiphyte load Often “rusty-red” in the field Epithemia adnata Cyanobacteria endosymbionts

8. Are algae really important to frog populations? Measured or Estimated a mean and a variance for each parameter * strand/scour of clutches embryo survival within an intact clutch tadpole survival to metamorphosis overwintering survival of juvenile Life stages and transition probabilities included in a stochastic matrix model

9. Population viability is sensitive to tadpole fate Used results of manipulative experiments on tadpole ability to withstand high discharge events and low algal food availability

10. Invasive Diatom, Didymosphenia geminata

13. Power peaking creates daily stage fluctuations

14. Varial zone where Didymo dominates Middle Fk. American

15. North Fk Feather, Rock Creek Reach Varial zone dominated by native diatoms with mucilaginous stalks "Thread of clubs" club ( -gompho) thread (- nema) Cymbella

16. Mucilaginous species tolerate wetting and drying in varial zone

18. Thermal changes due to level of outfall

19. Temperature monitoring Comparisons: Similar elevation regulated vs. unregulated sites Same site at different discharges

20. Altered thermal regimes

22. Biomass on Cobbles Species Composition / Nutritional Analyses (in process)

23. mg ash free dry mass / cm 2 0.4% Nitrogen 2.5% N ? Biomass comparison among treatments

24. Relative weight change over 72 hrs 2-way ANOVA results: Periphyton F 2,21 = 40.1 P < 0.001 Temperature F 1,21 = 35.4 P < 0.001 Periphyton Source x Temperature F 2,21 = 6.5 P = 0.006

25. Food Consumption Tadpoles consumed more 2-3 x more in warm treatment, except Feather 2-way ANOVA results: Periphyton F 2,21 = 13.2 P < 0.001 Temperature F 1,21 = 29.7 P < 0.001 Periphyton Source x Temperature F 2,21 = 7.9 P = 0.003

27. www.biosecurity.govt.nz http://www.nps.gov/yose/naturescience/upload/Didymo-fact-sheet-04-10.pdf Avoid felt-soled boots Help stop the spread of Didymo