Recruitment in Wild Smolt and Adult Steelhead Trout: the 30-year Experience at the Keogh River....
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Transcript of Recruitment in Wild Smolt and Adult Steelhead Trout: the 30-year Experience at the Keogh River....
Recruitment in Wild Smolt and Recruitment in Wild Smolt and Adult Steelhead Trout: the 30-Adult Steelhead Trout: the 30-year Experience at the Keogh year Experience at the Keogh
RiverRiver..Bruce R. WardBruce R. Ward
B.C. Ministry of Environment, U.B.C.B.C. Ministry of Environment, U.B.C.
AndAnd
Don J.F. McCubbingDon J.F. McCubbingIn-Stream Fisheries Research Inc., In-Stream Fisheries Research Inc.,
Vancouver, B.C.Vancouver, B.C.
Funding Funding Habitat Conservation Trust FundHabitat Conservation Trust Fund
Study LocationStudy Location
Steelhead of the Keogh Steelhead of the Keogh RiverRiver
Trends in Adult Steelhead Trends in Adult Steelhead at the Keogh Riverat the Keogh River
Trends in Smolt Yield at Trends in Smolt Yield at KeoghKeogh
Steelhead survival and abundance trends
1960 1965 1970 1975 1980 1985 1990 1995
Ocean Entry Year (t-3)
0
1
2
3
4
5
6
7
8
9
10
Ore
go
n M
arin
e S
urv
ival
(%
)
0
5
10
15
20
25
30
Keo
gh
R M
arine S
urvival (%
)
1960
-77
(6.1
%)
1978
-90
(3.3
%)
1991
-95
(0.6
%)
Oregon CohoKeogh Steelhead
Oregon Coho & BC (Keogh) Steelhead
Conservation designation
Recruitment from the Recruitment from the OceanOcean
smolt-to-adult survival trendsmolt-to-adult survival trend
Smolt-to-Adult SurvivalSmolt-to-Adult Survival
Climate ChangeClimate Change our management, policy
and legal systems, plus many of our built environments may not resilient enough to cope with real present day or projected future changes in fish, salmon, and habitats that result from climate change and weather extremes.
http://fisheries.c-ciarn.ca/
Climate Change and Climate Change and SteelheadSteelhead
•El Nino/La Nina
•Pacific Decadal Oscillation
•Global Climate Change
Back-Calculated Smolt Length and Back-Calculated Smolt Length and SurvivalSurvival
0.0
5.0
10.0
15.0
20.0
25.0
30.0
35.0
40.0
45.0
14 16 18 20 22 24 26
BACK-CALCULATED SMOLT
LENGTH (cm)
% survival
Observed and Expected Survival Observed and Expected Survival Rates Rates
Wild Steelhead @ Keogh RiverWild Steelhead @ Keogh River
0.00
5.00
10.00
15.00
20.00
25.00
30.001
97
7
19
79
19
81
19
83
19
85
19
87
19
89
19
91
19
93
19
95
19
97
19
99
SMOLT YEAR
SM
OL
T-T
O-A
DU
LT
SU
RV
IVA
L
(%)
Observed
Expected
Tracking wild and LGB Tracking wild and LGB smolts in Queen Charlotte smolts in Queen Charlotte
StraitStraitM a inlan dB ritish C olu m b ia
V a n cou v er Islan d
Q u een C ha rlo tte Strait
Strait o fG eo rgiaMa in la nd BC
Va nc ou ve rIslan d
M a lc o lm Is l.
Ke o gh R ive rm o u th
R M
Surgically-Implanted SteelheadSurgically-Implanted SteelheadSmoltSmolt
(7 Months Post-Implantation)(7 Months Post-Implantation)
4.5 4.5 mosmos15 15 mosmos
Post 2004/2005 SurvivalsPost 2004/2005 Survivals
Species Survival to River Mouth
(%)
Survival to QCS Line (%)
FW survivors to QCS Line
(%)
Wild Steelhead smolt 77 31 40
Hatchery Steelhead smolt 71 29 42
Steelhead Smolt Recruitment @ KeoghSteelhead Smolt Recruitment @ Keogh
0
2000
4000
6000
8000
10000
12000
0 500 1000 1500 2000 2500 3000
80's
Fert
90s
WRP
0
2000
4000
6000
8000
10000
12000
0 200 400 600 800 1000
Spawners
Sm
olt
Re
cru
its 80s
Fert
90s
WRP
rplcmt@ 4%
rplcmt@15%
1990’s regime affects 1990’s regime affects freshwaterfreshwater
0
2000
4000
6000
8000
10000
12000
0 200 400 600 800 1000
Spawners
Sm
olt
Re
cru
its 80s
Fert
90s
WRP
rplcmt@ 4%
rplcmt@15%
Freshwater capacity falls 6000 to less than 3000
Climate changes in freshwater as well
Spring migrationSpring migration(r(r22=0.65)=0.65)
Steelhead Parr per meter Steelhead Parr per meter in Treatment and Control in Treatment and Control
HabitatsHabitats
0
20
40
60
80
100
Controls Structures Nutrients Structures& Nutrients
num
ber
per
met
re
Mean length of 2-year-old (broken line, Mean length of 2-year-old (broken line, circles) and 3-year-old (solid line, squares) circles) and 3-year-old (solid line, squares)
steelhead smolts. Open markers indicate years steelhead smolts. Open markers indicate years affected by nutrient addition. Odd- and even-affected by nutrient addition. Odd- and even-
year variation is attributed to Pink salmon year variation is attributed to Pink salmon abundance.abundance.
Percent composition of age 1 (grey bar), age 2 (black bar), age 3 (white bar), and age 4 (hatch bar) steelhead smolts in
the Keogh River in 1996 and 1997 (no nutrient addition), and from 1998 to 2003 (nutrients added).
y = -0.0013x + 3.3284
y = -0.0032x + 2.616
0.0
0.5
1.0
1.5
2.0
2.5
3.0
3.5
4.0
4.5
0 500 1000 1500 2000 2500 3000
Spawners
ln(s
mol
ts/s
paw
ner)
1980s
1990s
Fert
WRP
Smolts per spawner production
Steelhead smolt recruitsSteelhead smolt recruits
0
10
20
30
40
50
60
0 1000 2000 3000
Number of Spawners
Nu
mb
er o
f S
mo
lts
per
Sp
awn
er
80s
Fert
90s
WRP
Predicted
Replacement at 15%
Replacement at 4%
Recruitment in FreshwaterRecruitment in Freshwater
0
10
20
30
40
50
60
70
0 1000 2000 3000
Number of Spawners
Nu
mb
er
of
Sm
olt
s p
er
Sp
aw
ne
r
80sFert90sWRPPredicted
The steelhead smolts per spawner and number of spawners in the Keogh River during the 1980s (diamonds) and the 1990s (triangles), nutrient experiments in the mid-1980s (squares), and initial results during WRP to 2003 (circles). Our modified Beverton-Holt fit to these data (solid points) statistically distinguishes the 1980s and nutrient experiments from all other treatments, while the 1990s and initial watershed restoration treatments cannot be statistically distinguished.
SummarySummary >30-yrs of study of freshwater and marine influences >30-yrs of study of freshwater and marine influences
to variation in steelhead recruitment implicate mainly to variation in steelhead recruitment implicate mainly climate climate
Trends in adult and smolt abundance suggest Trends in adult and smolt abundance suggest production regimes cahnges in bothproduction regimes cahnges in both
Trends in abundance and survival at Keogh are Trends in abundance and survival at Keogh are mirrored over a broad geographic area of the mirrored over a broad geographic area of the southern distribution, and in other species (e.g., southern distribution, and in other species (e.g., coho) suggesting a common cause.coho) suggesting a common cause.
Mortality in the ocean duriung t he first few weeks Mortality in the ocean duriung t he first few weeks appears high, but requires further studyappears high, but requires further study
Productivity and capacity in freshwater is altered by Productivity and capacity in freshwater is altered by nutrient dynamics, including marine-derived nutrient dynamics, including marine-derived nutrients from Pink salmonnutrients from Pink salmon
and probably habitat destruction/restorationand probably habitat destruction/restoration A highly variable riverine environment controlled by A highly variable riverine environment controlled by
precipitation affects all steelhead life stagesprecipitation affects all steelhead life stages
Divine Intervention?Divine Intervention?or rather - playing God!or rather - playing God!
Wild (98-02) and Wild/Living Gene Bank Wild (98-02) and Wild/Living Gene Bank (2003) (2003)
Steelhead Counts - Keogh River Steelhead Counts - Keogh River
0
50
100
150
200
250
300
350
12/1
12/8
12/1
5
12/2
2
12/2
9
1/5
1/12
1/19
1/26 2/2
2/9
2/16
2/23 3/2
3/9
3/16
3/23
3/30
Date
No
s o
f F
ish
1998
1999
2000
2001
2002
2003
0
20
40
60
80
100
120
140
12/1
12/8
12/1
5
12/2
2
12/2
9
1/5
1/12
1/19
1/26 2/
2
2/9
2/16
2/23 3/
2
3/9
3/16
3/23
3/30
Date
No
s o
f F
ish
1998
1999
2000
2001
2002
2003
•Increased adults, but….will this increase recruits?