Imnaha River Smolt Survival andSmolt to Adult Return Rate Quantification(Imnaha River Smolt Monitoring Program)

BPA Project Number 199701501

Nez Perce Tribe Department of Fisheries Resources Management

Authors: Jay A. Hesse, Peter J. Cleary,

Michael L. Blenden, and Paul A. Kucera

Associated Projects

• Fish Passage Center Smolt Monitor Program by non-federal Entities– In-season (real time) flow (spill) management

– Hydrosystem configuration effectiveness/impact assessment

– Long-term (time series) trend monitoring (status)

• Lower Snake River Compensation Plan Evaluation Studies– Hatchery Performance and Effectiveness

Project Background

Smolt Emigration Studies began in 1993 at Cow Cr. (rkm 7) with funds from the Lower Snake River Compensation Plan (LSRCP).

Participation in the Fish Passage Center’s Smolt Monitoring Program began in 1994 as part of BPA Project 198712700

Project funding was obtained directly from BPA in 1998

Major study design changes were proposed, but not funded, in 2002 for year round monitoring and obtaining smolt-to-adult returns for natural chinook salmon

Current Goals

Imnaha Smolt Monitoring - Provide emigration information to the Fish Passage Center while maintaining a time series of steelhead survival and arrival data to Lower Granite Dam, Lower Monumental Dam, and McNary Dam.

LSRCP - Provide information about juvenile chinook salmon biological characteristics, behavior and emigration timing, and survival and arrival timing to Snake River dams and McNary Dam.

Funded Objectives

•Describe emigration timing from the Imnaha River

•Monitor Imnaha River fish arrival timing and travel times to and through the mainstem Snake and Columbia rivers

•Estimate survival natural and hatchery fish from the Imnaha River subbasin to and through the mainstem Snake and Columbia rivers

•Provide information to the Fish Passage Center, Lower Snake River Compensation Plan Program, Northeast Oregon Hatchery Monitoring and Evaluation Program (NEOH M&E), and PTAGIS

• Located 7 km from the confluence of the Snake River

• Below all but one major tributary

• Situated on private property

Study Area

Imnaha River Juvenile Fish Trap

Approach• Juvenile Chinook Salmon and

Steelhead Emigrant Trapping (March 1 – June 15)

• PIT Tag Chinook Salmon and Steelhead– Weekly release groups of 200-1000

– Season-wide sample size of 11,000 chinook salmon and 5,000 steelhead

– Passage route control (SbyC)

• PIT Tag Interrogations of Smolts and Adults at Mainstem Dams and the Imnaha River

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020004000600080001000012000140001600018000

March April May June

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Smolt Emigration Timing

2001

2002

2003

Natural Chinook

Natural Steelhead

Hatchery Chinook

Hatchery Steelhead

Juvenile Hatchery Chinook Salmon Emigration Timing Imnaha

River 1998 - 2003

0

10

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30

40

50

60

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100

0 5 10 15 20 25 30 35 40 45 50 55 60 65 70 75

Days After Release

Arr

ival

Fre

quen

cy (

%)

.Hatchery Chinook 2003 Hatchery Chinook 2002

Hatchery Chinook 2001 Hatchery Chinook 2000

Hatchery Chinook 1999 Hatchery Chinook 1998

Date Hatchery Chinook Were Forced Out

Size at Emigration2003 Imnaha River Steelhead

0

3

6

9

12

15

55 75 95 115

135

155

175

195

215

235

255

275

295

Length (mm)

Fre

quen

cy (

%)

.

Natural Steelhead Hatchery Steelhead

Size at Emigration 2003 Imnaha River Chinook Salmon

0

5

10

15

20

25

55 75 95 115

135

155

175

195

215

235

255

275

295

Length (mm)

Fre

quen

cy (

%)

.

Natural Chinook Salmon Hatchery Chinook Salmon

0

30

60

90

3/25 4/84/22 5/6

5/20 6/36/17 7/1

7/15 7/29 8/12

Date of Arrival at Lower Granite Dam

Arr

ival

Tim

ing

(%)

.

Upper Trap - Fall 2000 Lower Trap - Fall 2000 Spring - Lower 2001

Imnaha River Natural Juvenile Chinook Salmon Arrival Timing at Lower Granite Dam

0%

30%

60%

90%

3/23 3/30 4/64/13 4/20 4/27 5/4

5/11 5/18 5/25 6/1 6/86/15 6/22 6/29 7/6

7/13 7/20

Date of Arrival at Lower Granite Dam

Arr

ival

Tim

ing

(%)

.

Spring Fall

2001

2003

1-May11-May21-May31-May10-Jun20-Jun30-Jun10-Jul20-Jul

1994

1995

1996

1997

1998

1999

2000

2001

2002

2003

Migration Year

Day

of

the

Yea

r

Natural Hatchery

90% Arrival Timing of Steelhead at Lower Granite Dam

(1994 to 2003)

90% Arrival Timing of Chinook Salmon at Lower Granite Dam

(1992 to 2003)

1-May

11-May

21-May

31-May

10-Jun

1992

1994

1996

1998

2000

2002

Migration Year

Day

of

the

Yea

r

Hatchery Natural

0.0%

20.0%

40.0%

60.0%

80.0%

100.0%

April 13 April 20 May 27 May 4 May 11

Week of Release

Surv

ival

(%

)

Lower Granite Dam Lower Monumental Dam

Weekly Survival of Hatchery Steelhead from the Imnaha River to Lower Granite and Lower

Monumental Dams in 2003

Season-wide Juvenile Steelhead Survival Estimates to Lower Granite Dam

Imnaha River 1995 -2003

0102030405060708090

100

1995 1996 1997 1998 1999 2000 2001 2002 2003

Year

Sur

viva

l Est

imat

e (%

) .

Natural Hatchery

d

0102030405060708090

100

1998 1999 2000 2001 2002 2003

Year

Survi

val E

stima

te (%

)

Natural Hatchery

Season-Wide Juvenile Survival Estimates to McNary Dam

Natural and Hatchery Steelhead 1998 to 2003

Post Release Survival Hatchery Chinook Salmon

(Gumboot Acclimation Facility to Mouth of Imnaha River)

0102030405060708090

100110

1994 1995 1996 1997 1998 1999 2000 2001 2002 2003

Migration Year

Surv

ival

(%

) .

n = 3,974 n = 13,378

n = 19,827

n = 23,425

n = 20,149n = 20,922

n = 20,917

n = 2,993 n = 4,715 n = 20,904

0102030405060708090

100

1993 1994 1995 1996 1997 1998 1999 2000 2001 2002 2003

Year

Sur

viva

l E

stim

ate

(%)

Natural Hatchery

Season-wide Juvenile Chinook Salmon Survival Estimates to Lower Granite Dam

Imnaha River 1993 - 2003

0102030405060708090

100

1998 1999 2000 2001 2002 2003

Year

Survi

val E

stima

te (%

)

Natural Hatchery

Season-Wide Juvenile Survival Estimates to McNary Dam

Natural and Hatchery Chinook Salmon 1998 to 2003

Summary• Tributary-specific contribution to Fish Passage Center Smolt

Monitor Program basin aggregate monitoring.• Maintains a time series of tributary-specific juvenile survival

estimates to and through the Snake and Columbia river hydrosystem.– Natural chinook salmon survival to Lower Granite Dam range from

76 to 91%.– Hatchery chinook salmon survival to Lower Granite Dam range from

67 to 80%.– Natural steelhead survival to Lower Granite Dam range from 82 to

90%. – Hatchery Steelhead survival to Lower Granite Dam range from 64 to

89 %.

• Primary data and survival estimates available real time on line at WWW.FPC.BPA.GOV and WWW.CQS.WASHINGTON.EDU

• Annual reports posted at WWW.EFW.BPA.GOV

Future Direction Representative Juvenile Trapping and Marking (Year-Round) Provide estimates of juvenile emigrant abundance at Imnaha rkm

7 Measure the SAR for Imnaha River natural chinook salmon and

steelhead from the Imnaha River to the Imnaha River, from Lower Granite Dam to Lower Granite Dam, and from Lower Granite Dam to the Imnaha River

Measure Juvenile survival to Lower Granite Dam (and McNary Dam)

Estimate Imnaha River natural chinook salmon and steelhead smolt equivalents at Lower Granite Dam

Questions?