Marine perspectives on Chinook salmon hatchery production in the Columbia River Basin

Transcription

1 Marine perspectives on Chinook salmon hatchery production in the Columbia River Basin Brian Beckman, Larissa Rohrbach and David Teel Northwest Fisheries Science Center, NOAA Fisheries Seattle, WA

2 Yearling Chinook salmon Columbia River hatchery production ~ 33 million/year Spring Mid & Upper Columbia River West Cascade Rivers X Spring Summer/Fall All juvenile salmon pass under the bridge at Astoria Fall Snake River Early marine habitat of juvenile salmon Willamette River Spring Spring

3 Current Columbia River Basin management paradigm #1: more smolts = more adults

4 New Columbia River hatchery programs will release an additional 12 million smolts, (all species) Chief Joseph 2.9M spr/sum Chinook smolts Springfield Hatchery 1.0M sockeye smolts Penticton Hatchery 1.0M sockeye fry Walla Walla Hatchery 0.5M spring Chinook smolts Nason Creek Hatchery 0.2M spring Chinook smolts John Day mitigation 6.0M fall Chinook smolts Holmes Hatchery 0.7M coho parr/smolts

5 Abundance of Columbia River Spring chinook salmon adults varies Smolt production relatively constant during this period Adult spring Chinook at Bonneville (USACE) Bad ocean Good ocean 2014? Return year

6 Current Columbia River Basin management paradigm #2: Ocean variability is unpredictable and production responses are unmanageable

7 Manage for good or bad ocean? Manage for optimal production in good years or bad years? Manage for total salmon return or return of selected stocks/species? Note: El Nino prediction for 2015?

8 El Nino?

9 Goal: generate discussion on interactions between ocean resources, smolt abundance and smolt size Outline: marine growth and survival varying size-biased survival of hatchery smolts size and marine growth

10 What about salmon in the ocean? NOAA Juvenile Salmon Ocean Survey present

11 T I 125 W 124 W 123 W NOAA Salmon Survey May, June and September starting in N LaPush 47 N Washington 2013, June only 4 This talk: May and June data 46 N Astoria Yearling Columbia River Chinook salmon 45 N Tillamook Oregon 180m Newport

12 Why does marine survival vary? Adult spring Chinook at Bonneville Return year

13 What do salmon do in the ocean? Eat & Grow

14 mean IGF1 (+/- se) Adult spring Bonneville Marine growth* varies between years, growth is related to survival (Columbia River spring Chinook Salmon) Growth* of UCR/SnkR Spring Chinook varies between years Growth is related to adult return 95% CI r 2 =0.85, p < Ocean Entry Year mean IGF1** (+/- se) (UCR/Snk spring Chinook salmon) *Growth in June ~ 2-6 weeks post-ocean entry ** IGF1 is a hormone that reflects growth rate

15 Growth varies => Food is limited in some years If food is limited => there is competition for food

16 Change focus from the ocean to hatcheries

17 Most (all?) hatcheries have release targets How does smolt size at release relate to marine survival??

18 Bonneville Dam Carson NFH Yearling spring Chinook salmon

19 How does smolt size of surviving adults vary between years? Queried PTAGIS Adults: PIT-tags at Bonneville Adult Ladder by release yr minijacks (age 2) jacks (age 3) age 4 Smolts: generated mean size at tagging by release yr minijacks jacks age 4 mean size at tagging is a surrogate for smolt size => related mean size at tagging of surviving adults to ocean conditions

20 Carson data Adult spring Chinook at Bonneville Return year

21 Size at tagging (mm) Size at tagging (mm) Size at tagging (mm) Size selective mortality is more intense during bad ocean years (-PDO = good for salmon) r 2 = r 2 = Age 2 (minijack) Age 3 (jack) May PDO May PDO Slopes similar => Suggests common mechanism between age classes r 2 = Age May PDO

22 Size selective mortality occurs (in 1st ocean year) More intense selection in bad ocean years

23 Why does survival vary with size?

24 IGF1 Yearling Columbia R Chinook salmon: marine growth varies with size Length (mm) , May, all stocks p<0.001, r 2 =0.20

25 IGF1 - size relationships vary between years (slope of regression line) Snake River spring Chinook salmon

26 IGF vs Length slope varies with ocean conditions Bad ocean >>> Good ocean ~

27 IGF1 - size relationships vary between years due to varying ocean conditions Good ocean Bad ocean Snake River spring Chinook salmon

28 Size- biased growth occurs Big fish have higher growth than smaller fish in bad ocean years

29 More hatchery data

30 WestCSp WillRSp MUCRSp SnkSp SnkFa UCRSuFa WestCSp WillRSp MUCRSp SnkSp SnkFa UCRSuFa Weight (g) Release size of yearling Chinook salmon varies 2-fold by stock 14 Fish Released (millions) Release Size Fish Passage Center

31 What about salmon in the ocean? NOAA Juvenile Salmon Ocean Survey

32 WestCSp WillRSp MUCRSp SnkSp SnkFa UCRSuFa WestCSp WillRSp MUCRSp SnkSp SnkFa UCRSuFa weight (g) weight (g) Weight of fish caught in the ocean varies > 2-fold by stock May June

33 Upriver spring yearlings have lower growth in May IGF Downriver Spring Upriver Summer/Fall Upriver Spring

34 Different stocks have differing smolt sizes Different stocks have differing early marine growth rates

35 Do different stocks have differing size-based marine mortality rates? Do stock specific sizebased mortality rates vary with ocean conditions?

36 El Nino?

37 Summary: - marine growth is limited in some years - marine survival is related to marine growth - size selective marine mortality occurs - more intensive marine size selection in low marine growth years - differences in growth between big and small fish are greater in years with low marine growth - size varies among stocks - El Nino 2015?

38 Acknowledgements Ocean Ecology group NOAA NWFSC Cheryl Morgan Suz Hinton Cindy Bucher Bill Peterson Bob Emmett Paul Bentley Ric Brodeur Kym Jacobson Joe Fisher Laurie Weitkamp Captains & Crew F/V Frosti Physiology group NWFSC Deb Harstad Kathy Cooper Dina Spangenberg Shell Nance Dave Metzger Don Larsen Funding Bonneville Power NOAA Fisheries