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Unexpected effects and unintended consequences:altering emergence timing induces
variability in Chinook salmon life history
Brian Beckman, Don Larsen, Deb Harstad, Kathy Cooper, Dina Spangenberg and Paul Parkins
NOAA Fisheries, Northwest Fisheries Science Center, Seattle, WA
Northwest Fish Culture ConferenceNovember 2008
Columbia Riverspring Chinook salmonlife history is variable
““Spawning Spawning -- FallFall””
ocean rearingocean rearing
emergenceemergence
spring smoltingspring smolting(age 1+)(age 1+)
AgeAge--4 4
AgeAge--55
AgeAge--3 jack3 jack
fry
parr
maturationmaturation
Precocious parrage 1
miniJackage 2
fall smoltingfall smolting(age 1)(age 1)
10 years of sampling, >12,000 fish = 2 precocious parr (<0.02%)
Two important points:1). this appears to be quite low
data from other hatchery and wild populations2). most of the fish were sampled for Ray Brunson
Charlie Strom manager
Why so few precocious parr?
One of the reasons CESRF is special: (there are many)
Seasonal timing for ponding fry
Many hatcheries alter emergence (ponding) I). synchronize ponding
Compress(chill early egg take, warm later egg take)
3 months
3 weeks
Many hatcheries alter emergence (ponding) II). Pond “early” - longer growth period, clear egg stacks
Compress and shift early
(incubate at warm temp)
3 weeks
3 months
Many hatcheries alter emergence (ponding) III). Pond “late” - avoid silting of ponds, smaller size
Compress and shift late(incubate at cold temp)
CESRF
3 months
3 weeks
Does late ponding affect rate of age-1 male maturation?
What is “Natural Emergence Timing”?
BY 05 SPAWNING CHANNE
0
200
400
600
800
1000
1200
1400
1600
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2000
2200
2400
2600
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3000
3200
30-Nov-0510-Dec-0520-Dec-0530-Dec-059-Jan-0619-Jan-0629-Jan-068-Feb-0618-Feb-0628-Feb-0610-Mar-0620-Mar-0630-Mar-069-Apr-0619-Apr-0629-Apr-069-May-0619-May-06
# O
F FR
Y TR
APP
ED
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DA
ILY
AVE
TEM
P (C
)
Total # FRYTEMP
Data kindly provided by Steve Schroder,Todd Pearsons, Anthony Fritts, Jen Scott, Jordan Vandal, Gene Sanborn (WDFW) and Curt Knudsen (Oncorh Consulting).
Adults spawn within a few daysBut, progeny emerge/migrate over several months
7 weeks
Greater variation in juvenile emergence timing (weeks)than adult spawning (days)
“Natural” emergence timing greatly extendedas compared to many hatcheries
Experimental Question:
What is the effect of emergence timing on life-history variation?
Pond fry at 3 different photoperiods
1 December (early)15 February (middle)1 May (late)
Experimental approach:
Important!!
Purpose of experiment is to investigatelife history variation;
not, to develop protocols for CESRF(or any other hatchery).
My job is not to tell people what to do, my job is to helppeople understand their fish.
Growth rate is also important (Don Larsen ad nausea):
Larsen, D.A., Beckman, B.R., Strom, C., Parkins, P., Cooper, K.A., Fast, D., and Dickhoff, W.W. 2006. Growth modulation alters the incidence of early male maturation and physiological development of hatchery reared spring Chinook salmon: a comparison with wild fish. Trans. Am. Fish. Soc. 135:1017-1032.
Larsen, D.A., Beckman, B.R., Cooper, K.A., Barrett, D., Johnston, M., Swanson, P., and W.W. Dickhoff. 2004. Assessment of high rates of precocious male maturation in a spring chinook salmon supplementation hatchery program. Trans Am. Fish Soc. 133:98-120.
feed fry at 3 different rates
LowHighSatiation
Experimental approach II:
30
50
70
90
110
130
150
170
Dec Feb Apr Jun Aug Oct Dec
Emergence time, growth and size were varied experimentally
Length (mm)
Fish grown in experimental tanks NOAA Montlake
Monitor Autumnal Smolting:24 hour seawater challenge
parr
freshwater sea water
smolts0% survival
100% survival
Monitor Age-1 (precocious parr) Maturation:milt expression or simple dissection
30
50
70
90
110
130
150
170
Dec Feb Apr Jun Aug Oct Dec
Emergence and growth of fish did vary
Target sizefor tagging @
CESRF
Thanks to Charlie Strom and CESRF staff for eggs
Average sizewild fish fall 93, 94
(Canyon - Union gap - Zillah)Beckman et al. 2000
Length (mm)
0
5
10
15
20
25
30
35
40
45
50
% survival24 hrs, 37.5 ppt
seawater(Sept - Nov)
Low High Sat Low High Sat Low High Sat
Feeding Rate
Early emerging fish smolt in the autumnlater emerging fish do not
EarlyEmerge
MiddleEmerge
LateEmerge
SW challenge
Late emerge fish do smolt the following spring
1
2
3
4
5
6
7
8
9
7/19
/07
8/23
/07
9/12
/07
10/
3/07
10/2
3/07
11/
9/07
11/2
7/07
12/2
0/07
1/11
/08
2/ 7
/08
2/29
/08
3/28
/08
Gill
ATP
ase
30
50
70
90
110
130
150
170
Length (mm)
0
10
20
30
40
50
60
70
80 Early Emerge
MiddleEmerge
LateEmerge
Low High Sat Low High Sat Low High Sat
% maturingMales
(% of total males)
Early emerging fish have a high propensityfor early male maturation (age 1)
(precocious parr)
Feeding Rate
0%
We split egg lots betweentreatments
⇒ Absolutely no geneticdifference between groups
SpawningSpawning
fry
emergenceemergence
earlyearly
latelate
Conclusion: Emergence timing mayprovide another axis for
life history variability
““Spawning - FallSpawning - Fall””
ocean rearingocean rearing
spring smoltingspring smolting(age 1+)(age 1+)
Age-4 Age-4
Age-5Age-5
Age-3 jackAge-3 jack
fry
parr
maturationmaturation
Precocious parrage 1
miniJackage 2
fall smoltingfall smolting(age 1)(age 1)
earlyearly
emergenceemergence
Early emergence accelerates life history
““Spawning - FallSpawning - Fall””
ocean rearingocean rearing
spring smoltingspring smolting(age 1+)(age 1+)
Age-4 Age-4
Age-5Age-5
Age-3 jackAge-3 jack
fry
parr
maturationmaturation
Precocious parrage 1
miniJackage 2
fall smoltingfall smolting(age 1)(age 1)
earlyearly
emergenceemergence latelate
Late emergence delays life history
““Spawning - FallSpawning - Fall””
ocean rearingocean rearing
spring smoltingspring smolting(age 1+)(age 1+)
Age-4 Age-4
Age-5Age-5
Age-3 jackAge-3 jack
fry
parr
maturationmaturation
Precocious parrage 1
miniJackage 2
fall smoltingfall smolting(age 1)(age 1)
earlyearly
emergenceemergence latelate
10 years of sampling, >12,000 fish = 2 precocious parr (<0.02%)
Late emergence delays life history
ImplicationsWhat happens in the hatchery does not stay in the hatchery, long-term life history implications for altering emergence (ponding) time exist.
No easy answers for “best” rearing program - a series of trade-offs between male maturation, size (taggingtargets), smolting and SAR.
Current rearing program (late ponding) mimics conditions found in head water streams (high elevation, cold - late emergence) and is favorable for yearling releases.