1. Pilot Mark-Recapture Study to Estimate Delta Smelt Pre-screen Loss and Salvage Efficiency G. Castillo 1 ; J. Morinaka 3 ; B. Baskerville-Bridges 2,4 J. Lindberg 2 ; R. Fujimura 3 ; J. Dubois 3 ;G. Tigan 2,3 ; V. Poage 1 1 U.S. Fish & Wildlife Service 2 Fish Conservation and Culture Laboratory-UC Davis 3 California Department of Fish & Game 4 Currently U.S. Fish & Wildlife Service

2. DWR Study Area Skinner Fish Facility Intake Radial Gates Clifton Court Forebay to SWP Pumps DWR

3. Skinner Fish Salvage Facility DWR

4. Skinner Fish Salvage Facility to SWP Pumps Primary Louvers Water Intake Collection and Transport Trash Rack Holding Tank

5. Project Goals To estimate: 1. Delta smelt’s pre-screen loss at Clifton Court Forebay (CCF) 2. Salvage efficiency of delta smelt at the Skinner Fish Facility

6. Objectives 1.Develop a mass-marking method for juvenile & adult delta smelt 2.Refine mark-recapture method to evaluate delta smelt’s salvage efficiency at Skinner Fish Facility (SWP) 3.Conduct preliminary mark-recapture tests in Clifton Court Forebay (CCF) to refine methods to estimate pre-screen loss of delta smelt

7. Marking Method Cultured Delta smelt FCCL-UC Davis Used SE-Mark Calcein under INAD process Calcein concentrations: 2.5 g/L (juveniles) and 5.0 g/L (adults) Calcein immersion tests: 0, 1, 3, 5, 7 min. Daily post-marking survival Calcein detector: fins (pelvic, pectoral, caudal), operculum, jaw, scales Two independent marking grade evaluations using calcein detector

8. Evaluation of Mark- Recaptured Delta Smelt

9. Calcein Marking Results 100% mark retention within 1 month post-marking Higher mark intensity with increasing immersion time Post-marking survival increased with: - Reduced light exposure (shaded windows) - Water temperatures < 16.5 o C At least 90% average survival 1 week after marking - Protocols to limit handling stress Similar survival between marked fish and unmarked control fish

10. 1 3 2 DWR Center CCF West CCF Fish Facility

11. Transport of Marked Delta Smelt to Skinner Fish Facility

12. Release at Skinner Fish Facility - Trash Rack (June 4) Near noon (4 groups 30 min. apart) Released 200 fish (50 fish per group / 5 gallon bucket x 4 groups) Release conducted c.a. 1 hr after export began (2,260 cfs)

13. Fish Releases at Skinner Fish Salvage Facility

14. Recaptures of Marked Delta Smelt Skinner Fish Facility Release W = Wild fish M = Marked fish

15. Transport of Marked Delta Smelt to CCF

16. Release in West Side of CCF (June 12) Daylight morning hours (two groups within minutes) Released 500 fish (250 fish per group / 80 L carboy x 2 groups) Release conducted c.a. 20 min. after exports began (375 - 2,260 cfs)

17. Fish Releases in Clifton Court Forebay

18. Recaptures of Marked Delta Smelt West CCF Release W = Wild fish M = Marked fish

19. Release Near the Center of CCF (June 26) Daylight morning hours (5 groups within minutes) Released 2,647 fish (c.a. 500 fish per group / 80L carboy x 5 groups) Release conducted c.a. 7 hours after exports began (2,260 - 3,390 cfs) Concurrent release of drifters at release site (hydrodynamic study)

20. Recaptures of Marked Delta Smelt Center CCF Release W = Wild fish M = Marked fish

21. 2830Percent 751Days CenterCCFWestCCFTrashRackRecapture 3 2 1

22. Ambient Temperature Controls for Marked Delta Smelt Fish transported to outdoor holding tank (n=100) Daily Feeding and monitoring: -Temperature -Turbidity -Survival

23. Delta Smelt Controls for two Releases in CCF

24. Conclusions 1- Calcein seems appropriate for mass mark-recapture experiments on juvenile and adult delta smelt 2- Significant decrease in percent of recapture and increased time of recapture with distance to Skinner Fish Facility 3- Water temperatures above 25 o C may have increased mortality of juvenile delta smelt in Clifton Court Forebay

25. Cooperation & Coordination: Luke Ellison (FCCL-UC Davis) Jennifer Messineo (DFG) Kim Webb (USFWS) Raul Piedrahita (UC Davis) Theresa Rettinghouse (FCCL-UC Davis) Marty Gingras (DFG) Paul Cadrett (USFWS) Robert Clarke (USFWS) Sheryl Moore (DWR) Cathy Ruhl (USGS) Kevin Clark (DWR) Ed Gross (EC) Mark Bowen (USBR) Michael McWilliams (EC) Ted Sommer (DWR) Pete Smith (USGS retired) Andy Chu (DWR) Brynn Hooton (DFG) Denise Barnard (DFG) Paul Miklos (USFWS) Mike Marshall (USFWS) Science Aids (DFG) Katherine Kellogg-Campbell (DFG) Carlie Jackson (DFG) Crystal Kaphaem (DFG) Funding: CALFED Science Program Interagency Ecological Program U.S. Fish and Wildlife Service Acknowledgements