comparisons of reproductive success between hatchery and...
TRANSCRIPT
Comparisons of reproductive success between hatchery and natural fish: Current research and perspectives
• Ilana Koch
• Maureen Hess
• Shawn Narum
April 28, 2020
Milli
ons
of fi
sh
Year
Harvest HabitatHydro Dams Hatcheries
-Climate -Selection-Urbanization
759,347
1855: NPCC historical run extrapolation estimate; 1880-1920 data points extrapolated from Columbia River cannery output; 1940-present: dam counts and river mouth estimates
Primary purpose of salmonid hatchery programs = Mitigate for impacts caused by dams and development of the CRB
Major Decline in Salmonid Abundance in Columbia River
Returning Columbia River salmon (chinook, steelhead, sockeye, coho)
Pre-development Estimated Average: 17,000,000
Tribes and Hatchery Risks
Source: Paul Lumley, CRITFC executive director, 2008-2016
• “The tribes recognize that there is significant risk to wild fish associated with the production of hatchery fish.”
• “The job at hand is to manage that risk, with sound hatchery practices.”
• “The tribes insist that hatcheries must remain a tool to benefit recovery of imperiled wild stocks and help rebuild populations for both reproduction and harvest.”
• “As long as we have dams we’ll have hatcheries to provide mitigation for heavy losses.”
• Harvest augmentation – Fish for harvest (often segregated)
• Reintroduction – Restore extirpated populations (outside stocks, integrated)
• Supplementation – Prevent extirpation, rebuild natural production (integrated)
Management of Hatchery Programs
Integrated program
Hatchery Nature
ØLower degree of domesticationØLower genetic risk to natural
population
Two different management approaches
Segregated program
Hatchery Nature
Ø Higher degree of domestication (“hatchery-adapted”)
Ø Higher genetic risk to natural population
- Proportion of natural-origin fish in broodstock and hatchery-origin fish on spawning grounds varies by program and year
- Intended to maintain diversity necessary for long-term persistence- Domestication expected to decrease with high proportion of natural-
origin broodstock
Integrated Supplementation Programs
Dom
estic
atio
n
% Natural-origin broodstock
Expectation:
• Supplementation – Prevent extirpation, rebuild natural production (integrated)
Integrated program
Hatchery Nature
ØLower degree of domesticationØLower genetic risk to natural
population
The Role of Genetic Sampling in Supportive Breeding
• Genetic sampling can provide insight into numerous individual and population-level assessments:� Diversity within and among populations� Connectivity among populations� Genes underlying traits (i.e. migration timing)� Parentage Analyses (i.e. Parentage Based Tagging; PBT)
• Parentage analyses can provide insight into fitness differences (reproductive success; RS) between hatchery- and natural-origin fish.
Relative Reproductive Success (RRS)
Avg # offspring (Natural origin)Avg # offspring (Hatchery origin)
RRS =
2 offspring (Nat.)
2 offspring (Hat.)RRS = = 1.0
2 offspring (Nat.)
1 offspring (Hat.)RRS = = 0.5
Equal Fitness Lower Fitness
Studies In Salmonids and Risks to Natural-Origin Fish
• Steelhead� Lower success of hatchery-origin compared to natural-origin fish1
� Success of natural-origin fish reduced when mating with hatchery-origin fish1
� Natural-origin broodstock produce offspring that reproduce better in nature2
• Coho� No differences in success between hatchery- compared to natural-origin fish3
� Lower success of hatchery-origin compared to natural-origin fish, except for jacks4
• Chinook� Lower success of hatchery-origin compared to natural-origin fish5,6
� More generations in hatchery leads to lower success in the wild for males6
� No effect detected when natural-origin fish mate with hatchery-origin fish5
1Kostow et al. 2003; McClean et al. 2003, 2004; Araki et al. 2007, 2009; Berntson et al. 20112Ford et al. 20163Ford et al. 2006; O’Malley et al 20154Theriault et al. 20115Hess et al. 2012; Janowitz-Koch et al. 20196 Williamson et al. 2010; Ford et al. 2012; Anderson et al. 2013; Evans et al. 2015
Summary: Results vary by species and hatchery program
Spring/Summer Chinook salmon (Oncorhynchus tshawytscha)• Threatened or endangered in many locations
• Johnson Creek: spawning tributary in interior watershed of Salmon River Basin (Idaho)� All fish are passed above the weir for natural spawning.� Only natural-origin fish are used for broodstock.
Methods: Sample Collection• Fin tissue sample collected and data recorded from all fish at
Johnson Creek weir (~93% of spawning adults)
• Samples genotyped for parentage analyses
• Tissue samples from approximately 14,500 fish between 1998-2016� 19 collection years and 10 brood years examined in this study: 2002-
2011
34
5
00 02 03 04 05 1199 01 1498 1008 09 12 13 1606 150702 03 04 05 06
Questions
Evaluate the long-term effects of supplementation over two full generations in Johnson Creek: 1. Does the hatchery boost population abundance?
2. Do hatchery-origin fish demonstrate lower (or higher) reproductive success than natural-origin fish?
3. What are some of the key factors affecting variation in reproductive success?
Result 1: Demographic Boost• First generation:
Broodstock produced ~5 times the number of returning adult offspring compared to natural spawners (average = 4.52).
• Second generation: Broodstock produced ~3 times the number of returning adult grand-offspring compared to natural spawners (average = 2.56).
Does the hatchery boost population abundance? YES
2.591.05
4.733.56
5.99
3.67 3.082.32 2.09 2.25 2.5
4.31
20.68
N/A13579
111315171921
1998 1999 2000 2001 2002 2003 2004 2005 2006 2007 2008 2009 2010 2011Return Year
F 0�D
emog
raph
ic B
oost
a)
1.20.74
3.362.9
6.36
2.312.04
1.56
N/A
1
2
3
4
5
6
7
1998 1999 2000 2001 2002 2003 2004 2005 2006Return Year
F 1�D
emog
raph
ic B
oost
b)
2.591.05
4.733.56
5.99
3.67 3.082.32 2.09 2.25 2.5
4.31
20.68
N/A13579
111315171921
1998 1999 2000 2001 2002 2003 2004 2005 2006 2007 2008 2009 2010 2011Return Year
F 0�D
emog
raph
ic B
oost
a)
1.20.74
3.362.9
6.36
2.312.04
1.56
N/A
1
2
3
4
5
6
7
1998 1999 2000 2001 2002 2003 2004 2005 2006Return Year
F 1�D
emog
raph
ic B
oost
b)
Janowitz-Koch, I, et al. 2018. Evol App.
Result 2a: Relative Reproductive Success- All Sampled Adults
• Trend toward lower reproductive success for hatchery-origin fish, especially for:
• Females: 2007
• Males: 2002 & 2008
• Jacks: 2003 & 2008
Do hatchery-origin fish exhibit lower reproductive success than natural-origin fish? In certain years YES, but OVERALL, NO.
Successful Spawners
0
0.5
1
1.5
2
2.5
0
0.5
1
1.5
2
2.5
3
3.5
Rel
ativ
e R
epro
duct
ive
Succ
ess
(95%
CI)
FemaleMaleJack
b)
Successful Spawners
All Spawners
0
0.5
1
1.5
2
2.5
3
3.5
3
3.5
Rel
ativ
e R
epro
duct
ive
Succ
ess
(95%
CI)
FemaleMaleJack
a)
b)
Successful Spawners
2002 2003 2004 2005 2006 2007 2008 2009 2010 2011
0
0.5
1
1.5
2
0
0.5
1
1.5
2
2.5
3
3.5
Return Year
Rel
ativ
e R
epro
duct
ive
Succ
ess (
95%
CI)
FemaleMaleJack
b)
Successful Spawners
2002 2003 2004 2005 2006 2007 2008 2009 2010 2011
0
0.5
0
0.5
1
1.5
2
2.5
3
3.5
Return Year
Rela
tive R
epro
duct
ive S
ucce
ss (9
5% C
I)
FemaleMaleJack
b)
Janowitz-Koch, I, et al. 2018. Evol App.
Result 2b: Relative Reproductive Success- Single Generation Crosses
• No difference in reproductive success of Hatchery-origin x Natural-origin crosses compared to Natural-origin x Natural-origin crosses.
• No difference in reproductive success of Hatchery-origin x Hatchery-origin crosses compared to Natural-origin x Natural-origin crosses.
Do hatchery-origin fish impact the reproductive success of natural-origin fish? NO
Janowitz-Koch, I, et al. 2018. Evol App.
Result 3: The Impact of Size on Reproduction
• As body length increases, reproductive success also increases.
• In some years, hatchery-origin fish are smaller and have lower reproductive success.
Janowitz-Koch, I, et al. 2018. Evol App.
• Supplementation programs provide a boost in population abundance (survival advantage in hatchery)
• Hatchery adults have lower reproduction when spawning in nature in some cases, but decrease is slight overall
• Smaller, younger males (jacks) have lower reproductive success
• No effect detected when natural-origin fish mate with hatchery-origin fish
Overall: Limited effects for integrated hatchery programs that use ~100% natural origin fish in broodstock
General Conclusions from Case Studies in Chinook
Results in Steelhead: Natural-origin broodstock produce offspring that reproduce better in nature (Ford et al. 2016, PLOS One)
Integrated vs. Segregated Programs• Results support that integrated programs have lower
risks to natural populations than segregated programs• However, very few integrated hatchery programs with
high percent of natural origin broodstock
0
10
20
30
40
50
60
70
80
90
100
Nat
ural
Orig
in B
rood
stoc
k (%
NO
B)
Hatchery Program
Highly Integrated
Modest Integrated
Low Integrated or Segregated
Example from 25 Chinook Hatcheries
Credit: Rebekah Horn
� Additional studies needed that contrast integrated vs. segregated programs
� Evaluate differences after hatchery reform measures implemented
� Ensure genetic & life history diversity is maintained in natural populations
� Important that the breadth of RRS studies continue to expand across a wide range of salmonid species
� Evaluate the effect of annual environmental factors on reproductive success
Future Directions
Acknowledgments
Nez Perce Fisheries:Jay HesseBill YoungJason VogelField support technicians
Columbia River Inter-Tribal Fish Commission:Peter GalbreathJanae ColeStephanie Harmon Travis JacobsonLori MaxwellMegan MooreVanessa MormanJeff Stephenson
Photo Credit: Craig Rabe