Release Strategies to Improve Post-Release Performance of

Hatchery Summer Steelhead in Northeast Oregon.

Lance Clarke, Michael Flesher, Shelby Warren , and Richard Carmichael

By

STUDY DESIGN1. Acclimation vs. Direct-Release: One group released after a

16-57 day acclimation, the other group direct-released on same day. 14 paired groups.

• Spring Creek, (1987-1990)• Deer Creek, (1991-1996)• Little Sheep Creek, (1993-1996)

2. Volitional vs. Forced Release following Acclimation: Both groups acclimated for at least 27 days,1 group provided a 14-21 day volitional release the other group forced from acclimation pond. 6 paired groups.

• Spring Creek, (1996-1999)• Deer Creek, (1998-1996)

LOWER GRANITE DAM

SnakeRiver

Washington

Oregon

Gra

nde

RondeRiver

Wallowa River

Imnaha

River

Littl

e Sh

eep Cr

.

N

SpringC

r.

Deer C

r.

020 20 40

Kilometers

SNAKE RIVER BASIN STUDY AREA

Col umbiaR.

COMMON METHODS1. Rearing in hatchery raceways to yearling stage, water temperature

range = 10 -14 C. Fish trucked 3.5 to 4.5 h to acclimation sites.

2. Release groups of 25,000 to 50,000. Fish were freeze-branded or PIT-tagged to measure outmigration travel time and survival to

dam. All fish received coded-wire-tags; tag recoveries used to estimate smolt-to-adult survival and straying.

3. Acclimation ponds are rectangular and concrete, supplied with stream water.

Response Metrics 1. Outmigration Travel Time

2. Outmigration Survival

3. Smolt-to-Adult-Survival

4. Stray Rate Index

PIT Tagging and Coded-Wire-Tagging at Irrigon Hatchery

Big Canyon Acclimation Pond

Adult Returns to Wallowa Hatchery

ACCLIMATION VERSUS DIRECT-RELEASE RESULTS

0

20

40

60

80

100

120

140

AcclimatedDirect

1991 1992 1994 1995 1996

Deer Creek

19960

20

40

60

80

100

120

1993 1994 1995

Little Sheep Creek

TRAV

EL D

AYS

SIMILAR TRAVEL TIME TO LOWER GRANITE DAM

N = 163-509

(Paired t-test, P = 0.649)

RELEASE YEAR

% S

URVI

VAL

0

20

40

60

80

100

1987 1988 1989 1990 1991 1992 1993 1994 1995 1996

Spring Deer Little Sheep

ACCreek DR

SIMILAR OUTMIGRATION SURVIVAL TO DAM

P = 0.874

Vertical lines = 95% CI

% S

MOL

T-TO-

ADUL

T SU

RVIV

AL

0

0.5

1

1.5

2

2.5

RELEASE YEAR1987 88 89 90 91 92 93 94 95 1996

Spring Deer Little Sheep

ACCreek DR

ACCLIMATED GROUPS HAD HIGHER SURVIVAL TO ADULTHOOD (P = 0.013)

N = 8,260

93

RELEASE YEAR

% S

TRAY

RAT

E

0

5

10

15

20

25

30

1987 88 89 90 91 92 94 95 1996

35Creek

ACCLIMATED GROUPS HAD LOWER STRAY RATES (P < 0.001)

Spring Deer Little Sheep

AC DR

N = 861

020 20 40

Kilometers

Mouth (RK 0)

Pelton Trap (RK 161)

Sherars Falls (RK 69)

Warm Springs NationalFish Hatchery (RK 154)

Springs

Warm

River Deschutes

River

COLUMBIA RIVERDeschutes River Basin

54% Direct-Release

59% Direct-Release above Sherars Falls

56% of recoveries after 1 February were Direct-Release

% SURVIVAL TO LOWER GRANITE DAM

% S

MOL

T-TO-

ADUL

T SU

RVIV

AL

0

0.2

0.4

0.6

0.8

1.0

1.2

1.4

0 10 20 30 40 50 60 70 80 90

r 2 = 0.1122P = 0.1096N = 24

DOES OUTMIGRATION SURVIVAL MATTER?

VOLITIONAL RELEASE FORCED VERSUS

0

20

40

60

80

0

20

40

60

80

VolitionalForced Spring

Creek

Deer Creek

1997 1998 1999

19991998

TRAV

EL D

AYS

SIMILAR TRAVEL TIME TO LOWER GRANITE DAMN = 46-189

N = 40-61

P = 0.316

% S

URVI

VAL

0

20

40

60

80

100

Deer Spring

VOLCreek FR

1997 1998 1999

RELEASE YEAR

OUTMIGRATION SURVIVAL WAS SIGNIFICANTLY HIGHER FOR VOLITIONAL RELEASE (P = 0.035)

Vertical lines = 95% CI

0

0.2

0.4

0.6

0.8

1.0

SURVIVAL TO ADULTHOOD WAS NOT DIFFERENT (P = 0.658)

1996 1997 1998 1999

RELEASE YEAR

% S

MOL

T TO

ADU

LT S

URVI

VAL

N = 1,896

Deer Spring

VOLCreek FR

30

0

5

10

15

20

25

1996 1997 1998 1999

RELEASE YEAR

% S

TRAY

RAT

E Deer Spring

VOLCreek FR

VOLITIONAL RELEASE DID NOT REDUCE STRAYING (P = 0.852)

N = 194

Use of Volitional Release to Remove Residuals

Big Canyon Facility Little Sheep Facility

Release Year % Male

Numberremoved

Stream Density(no./100

m2) % MaleNumber removed

Stream Density(No./100

m2)2003 76 2,014 7.0 2004 65 0 9.22005 -- -- 5.6 92 8,470 13.82006 72 4,968 6.8 73 9,187 14.72007 67 0 21.3 81 9,701 10.62008 73 2,361 6.0 59 0 14.32009 84 2,457 5.6 78 4,733 8.22010 68 0 10.9 65 0 27.72011 70 0 3.5 65 0 16.8

2.0

0.0

0.5

1.0

1.5

MEAN

% S

MOL

T-TO-

ADUL

T S

URVI

VAL

..Survival to Adulthood, Four Month vs.

Two Month AcclimationTwo-factor ANOVA; P <0.005

Four Month Two Month

2000 2001 2002 2003 2004 2005RELEASE YEAR

(Spring Chinook, Umatilla Hatchery Program)

CONCLUSIONS1. Acclimation increased survival to adulthood and

decreased straying. Acclimation appears to ameliorate affects of stress.

2. Volitional release did not increase survival to adulthood or decrease straying. Survival results consistent with similar studies.

3. Juvenile outmigration survival did not correlate well with survival to adulthood.

Judge the success of release groups based on adult returns.

Survival results not consistent with other steelhead acclimation studies.

Management action: all releases are now acclimated.

Management action: retain some volitional releases to remove residuals.

Adjust Acclimation Protocols to the Hatchery Program

1. Acclimation locations, length, timing, feeding protocols, etc., can affect success of release groups. Hatchery specific investigations are needed. Unpublished data from the Wallowa program suggests that

straying is 30-40% higher for fish acclimated at Wallowa Hatchery than those at Big Canyon.

2. For supplementation programs, small temporary acclimation ponds spread throughout the watershed may promote a better distribution of returning adult spawners.

3. Acclimation is an ideal time to develop behavioral traits (i.e. prey or predator recognition training) that may improve survival.

4. Volitional release used as a tool to remove residuals; however, difficult to judge the success of that strategy.

For More InformationClarke, L.R., M.W. Flesher, T.A. Whitesel, G.R. Vonderohe, and R.W. Carmichael. 2010. Post-release performance of acclimated and direct-released hatchery summer steelhead into Oregon tributaries of the Snake River. North American Journal of Fisheries Management 30:1098-1109.

Clarke, L.R., M.W. Flesher, S.M. Warren, and R.W. Carmichael. 2011. Survival and straying of hatchery steelhead following forced or volitional release. North American Journal of Fisheries Management 31:116-123.

Clarke, L.R., W.A. Cameron, and R.W. Carmichael. 2012 Performance of spring Chinook salmon reared in acclimation ponds for two and

four months before release. North American Journal of Aquaculture 74: 65-72

NOW, WHAT DID HE SAY?