1. Avoidance of Aquatic Herbicides by Juvenile Salmonids CA Curran, JM Grassley, LL Conquest, and CE Grue Washington Cooperative Fish and Wildlife Research Unit School of Aquatic and Fishery Sciences University of Washington

2. Chemical Regulation Changes Permitting requirements Chemicals Used Renovate 3 (triclopyr) Reward (diquat) Sonar AS (fluridone) INTRODUCTION

3. Behavioral Responses and Herbicide Exposure Improve ecological relevance of toxicity test results Avoidance and attraction INTRODUCTION

4. Avoidance Test Methods Y-mazes Counter-Current Chambers Laminar Flow Systems INTRODUCTION

5. Chemical Clean Counter-Current Chamber ChemicalClean Y-maze ChemicalClean Laminar Flow

6. OBJECTIVE Do juvenile chinook avoid the herbicides at maximum concentrations and 10 times those concentrations? Renovate 3 (triclopyr): 2.50 and 25.0 ppm Reward (diquat): 1.37 and 13.7 ppm Sonar AS (fluridone): 90 and 900 ppb

7. METHODS

10. 45 minute test 0-14 minutes clean water flow 15-30 minutes chemical flow 31-45 minutes clean water flow Overall design focused on initial response to chemical flow Digital photos were taken every minute METHODS

12. Scoring method Position as a ratio of tube length, 0 to 1 InletOutlet Mean Fish Position 0.50 0.25 0.50 0.75 Minute 14 METHODS 01

13. InletOutlet Mean Fish Position 0.66 Chemical 0.45 0.60 0.85 Minute 16 Photograph taken each minute (total 45) to calculate mean position METHODS

14. Data Analysis Paired t-test to compare difference in mean position by minute blocks 0-14, 15-30, 31-45 Paired t-test to compare difference in slopes of mean positions within minute blocks Alpha level = 0.10 METHODS

15. Theoretical Response - Fast - Assessment by Level

16. METHODS Theoretical Response - Slow - Assessment by Level

17. METHODS Theoretical Response - Slow - Assessment by Slope

18. RESULTS Calcium Hypochlorite 1.6 ppm

19. RESULTS Sonar AS 900 ppm

20. RESULTS AnalysisSignificant?P-valueResult 1.6 ppmSlopeyes0.09Avoidance 1.6 ppmPositionno0.12No Effect Calcium Hypochlorite

21. RESULTS AnalysisSignificant?P-valueResult 2.5 ppmSlopeno0.50No Effect 2.5 ppmPositionno0.49No Effect 25 ppmSlopeno0.77No Effect 25 ppmPositionyes0.07Attraction Renovate 3

22. RESULTS AnalysisSignificant?P-valueResult 1.37 ppm Slopeno0.25No Effect 1.37 ppm Positionno0.40No Effect 13.7 ppm Slopeyes0.08Attraction 13.7 ppm Positionno0.56No Effect Reward

23. RESULTS AnalysisSignificant?P-valueResult 90 ppbSlopeno0.40No Effect 90 ppbPositionno0.96 No Effect 900 ppbSlopeno0.47No Effect 900 ppbPositionno0.35No Effect Sonar AS

24. CONCLUSIONS Original methods needed alterations Replication, tube shape, chemical delivery The apparatus functioned as expected Positive control results New statistical approach - change in mean position vs categorical tests Attraction to 10 times the maximum concentration of Renovate and Reward

25. FUTURE WORK Examination of olfactory performance following static exposure Examination of concentrations at time of application and rates of diffusion Effects of different testing procedures on avoidance/attraction results

26. ACKNOWLEDGEMENTS Funding was provided by Washington State Department of Ecology, SePro Corporation, and the School of Aquatic and Fishery Sciences and the Washington Cooperative Fish and Wildlife Research Unit at the University of Washington. A scholarship from Weed Science Society of America made my participation in this research possible Facilities provided by USGS’s Marrowstone Marine Station