barry a. berejikian and megan e. moore
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Variation in the effectiveness of alternative broodstock, rearing, and release practices
among three supplemented steelhead populations - Hood Canal, WA
Barry A. Berejikian and Megan E. MooreNOAA Fisheries Northwest Fisheries
Science Center, Manchester Research Station
Acknowledgements
• NWFSC Behavioral Ecology Team• Long Live the Kings• Hood Canal Salmon Enhancement Group• Washington Department of Fish and Wildlife• US Fish and Wildlife Service• US Forest Service• Hood Canal Private Landowners• Skokomish Tribe• Point No Point Treaty Tribes
Hatchery experiment• Replicated, before-during-after-control-impact experiment (RBACI)
• Response variables =
•spawner abundance and spawn timing,
•freshwater productivity (egg to smolt)
•life history diversity
•genetic variation
•Other stuff
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Kitsap
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Hood Canal stream habitat and population traits
~April 25
Domestication selection in steelhead hatcheries• Problem: Late/spring spawn timing of
wild steelhead precludes age-1 smolt rearing without inducing size selection after release
• Ha: Fitness loss caused bya. Selection for rapid growth rates
and correlated traits (vis. Berejikian et al. 1996, Reisenbichler et al. 2004,
Araki et al. 2008)b. Artificial breeding
• Potential solutions: Avoid artificial breeding and rear to modal age-at-smoltification
Hood Canal steelhead hatcheries
WDFW McKernan Hatchery
LLTK Lilliwaup Hatchery
Hamma HammaDuckabushDewatto
SF Skokomish
( C)
Release:Age-2 smolts
Age-4 and -5 adults
Egg collection and release numbers
Number of fish released
RiverBrood Year Redds
Eggs collected Age-1 Age-2 Age-4 Age-5
Total released
Dewatto 2007 16 9,438 0 7,375 226 24 7,601Dewatto 2008 24 9,327 0 6,807 6,807Dewatto 2009 9 9,171 0 6,571 6,571Dewatto 2010 7 5,861 51 51Dewatto 2011 20 7,276
Duckabush 2007 6 3,020 0 1,574 164 45 1,738Duckabush 2008 8 6,288 0 4,671 4,671Duckabush 2009 1 44 0 0 0Duckabush 2010 6 3,149 140 140Duckabush 2011 9 4,756
Skokomish 2007 39 35,290 4,091 23,747 54 27,892Skokomish 2008 50 34,813 200 20,529 20,729Skokomish 2009 44 29,952 0 26,642 26,642Skokomish 2010 41 29,712 0 0Skokomish 2011
Smolt quality
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2009 2010 2011
Skokomish1 2 3 M
Smolt index is significantly correlated with early marine survival(Moore et al. in prep)
Why differences in smolt quality?
Lilliwaup Hatchery
(Duckabush & Dewatto)McKernan Hatchery
(Skokomish)
Mean water temperature 8.9º C 8.6 º C
Feed Manufacturer Bio-Oregon Bio-Oregon
Feeding frequency 3x/d, 4 days/wk 2-3x/d, 7 days/wk
Mean density index (to age-1) 0.0066 0.290
Mean density index (age-1 to age-2) 0.0065 0.056
Vessel size/shape (to age-1) 10’ circular 16’ circular
Vessel size/shape (age-1 to age-2) 20’ circular 12 x 140’ raceway
# of size sorts (to age-1) 2 1
Summary• Juvenile steelhead rearing regimes can be
modified to match modal age-at-smoltification and natural smolt size
• Smolt quality and precocial male maturation can vary substantially between hatcheries even under the same protocols
• Rearing density may warrant a closer look
• Simple metrics for smolt quality correspond to early marine survival estimates
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