Pilot Mark-Recapture Study to Estimate Delta Smelt Pre-screen Loss and Salvage Efficiency

G. Castillo1; J. Morinaka3; B. Baskerville-Bridges2,4

J. Lindberg2; R. Fujimura3; J. Dubois3 ;G. Tigan2,3; V. Poage1

1 U.S. Fish & Wildlife Service2 Fish Conservation and Culture Laboratory-UC Davis3 California Department of Fish & Game4 Currently U.S. Fish & Wildlife Service

DWR

Study Area

Skinner Fish Facility

IntakeRadialGates

CliftonCourtForebay

to S

WP P

umps

DWR

SkinnerFish SalvageFacility

DWR

DWR

Skinner Fish Salvage Facility

to SWP Pumps

Primary Louvers

Water Intake

Collection and Transport

Trash Rack

Holding Tank

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

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

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

Evaluation of Mark- Recaptured Delta Smelt

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 oC

• At least 90% average survival 1 week after marking- Protocols to limit handling stress

• Similar survival between marked fish and unmarked control fish

624000 624500 625000 625500 626000 626500 627000

4187000

4187500

4188000

4188500

4189000

4189500

4190000

4190500

Clifton Court Forebay Bathymetry 12-2004

-60

-50

-40

-30

-25

-20

-15

-10

-8 .75

-7 .5

-6 .25

-5

-3 .75

-2 .5

-1 .25

0

5

UTM83 (Zone 10) in Meter

Elevation in Feet (NGVD29)

Elevation

1

3

2

DWR

Center CCF

West CCF

Fish Facility

Transport of Marked Delta Smelt to Skinner Fish Facility

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)

Fish Releases at Skinner Fish Salvage Facility

Recaptures of Marked Delta Smelt Skinner Fish Facility Release

W = Wild fishM = Marked fish

Transport of Marked Delta Smelt to CCF

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)

Fish Releases in Clifton Court Forebay

Recaptures of Marked Delta SmeltWest CCF Release

W = Wild fishM = Marked fish

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)

Recaptures of Marked Delta SmeltCenter CCF Release

W = Wild fishM = Marked fish

22883030PercentPercent

775511DaysDays

Center Center

CCFCCF

West West

CCFCCF

Trash Trash

RackRack

RecaptureRecapture

3

2

1

Ambient Temperature Controls for Marked Delta Smelt

Fish transported to outdoor holding tank (n=100)

Daily Feeding and monitoring: -Temperature -Turbidity -Survival

0.0

5.0

10.0

15.0

20.0

25.0

30.0

5/27 6/2 6/8 6/14 6/20 6/26 7/2 7/8 7/14

MONTH / DAY

TE

MP

ER

AT

UR

E (

oC

)

TU

RB

IDIT

Y (

NT

U)

0

20

40

60

80

100

SU

RV

IVA

L (

%)

Min °C Max °C Turbidity (NTU) Survival

Delta Smelt Controls for two Releases in CCF

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 oC may have increased mortality of juvenile delta smelt in Clifton Court Forebay

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 ProgramInteragency Ecological ProgramU.S. Fish and Wildlife Service

Acknowledgements