otolith chemistry reveals the diverse rearing habitats of winter...
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Corey Phillis, Metropolitan Water DistrictAnna Sturrock, U.C. DavisRachel Johnson, NOAA FisheriesPeter Weber, Lawrence Livermore National Laboratory
Otolith Chemistry Reveals the Diverse Rearing Habitats of Winter-Run ChinookSalmon
10-year winter-run otolith study spanning hydroclimatic regimes
1. Where do the successful winter-run rear as juveniles?
2. Are both fry and parr migrants represented in the adult population (based on otolith size)?
• Where do fry rear?
3. Are there differences in size at freshwater exit associated with juvenile rearing habitat?
• Or escapement year?
3 Research questions
Q1: Where do the successful winter-run rear as juveniles?
I’m a winner!!
Q1: Where do the successful winter-run rear as juveniles?
I’m a winner!!
What do I have to do to be like that guy?
Federal Register Vol. 58, No.114: Designation of ESA critical habitat for Sacramento River winter-run Chinook, 6/16/1993
Our conceptual models assume juvenile rear in the Sacramento and Delta
Hendrix et al., Life cycle monitoring framework for Sacramento River winter-run Chinook salmon, 2014
Narrative model Life-Cycle Model
Is rearing in the Delta a viable strategy?
And if not the Delta, where?
Q1: Where do the successful winter-run rear as juveniles?
Most juveniles begin moving downstream as fry
Proportion of total catch
Fork length (mm) of winter-run juveniles at RBDD RST
fry (<55)
Min. size for acoustic tag (> ~85)
parr (>55)
Most juveniles begin moving downstream as fry
Proportion of total catch
Fork length (mm) of winter-run juveniles at RBDD RST
fry (<55)
Where do these fry go to rear?
Sr isotopes discriminate habitats
· ·. r in the otoliths record outmigration
., Sr provides geographic data
., North-south gradient ~ 87Srf86Sr otolith = 87SrJB6Sr water
''What's in th1e water is in the otolith''
D Upper Sac. R .
D Lower Sac. R. & Delta
15] SF Bay Estuary
Pacific Ocean
San Francisco
Bay
• 188 otoliths (2007-2009 n = 29, 91, 68)
• Individuals assigned to 1 of 5 habitats:• Sacramento River (Keswick to Freeport)• American River• Northern Tributaries (e.g. Mill, Deer, Battle Creeks)• Delta or Feather River • “Habitat X”
• Detection limit for rearing in a habitat ~20 days
Individuals were assigned to juvenile rearing habitats
Strontium isotopes in otoliths record juvenile life-history
High Sr-isotope ratio and low Sr concentration hallmark of American River rearing
{b) American River 0.7,0
______ ,.. __ Rive k Loeatia Sr oonoo tration
AmericafJ RiLr'f.Jf Gold£:
9o 0.709 Gate Bay
UJ 0.708 Chipps m - 73 95% C.l. ~ ~SIMld
Dofra
en 0.707 - - - - - - - - - - - - - - -1'-- J
" ~fl-1\1.!1 t aJ J
aJ R ) "iri,;lHD b.i!Dt I
- ,75 I
0.706 r'oopor J
.... .- -- --- - -- --Sacramento River ... fR. 1'1- . I iJ 1 QLlrl·l~ 1 ,..:!-1fJ.!
0.705 - 567 ®dding .:: •.t.f].r:~ , .. i .1,-o.:ato
~---- -----------------.,.,__,_ ___ .,... ____ ..... ____ ,__
~1orthorn
0.704
200 300 400 500 SOO 700 ,BOO 000
Distance rom otolith core (~m)
Rearing in the Northern tribs indicated by Sr-isotope ratio lower than Sac R. minimum
(c) orth ern Trib·u tari es 0.710 Loeatia Sr oonoo trn.tion
Al11a.rica.n R · 1'
0 Gold£:
9o 0.709 Gate
UJ Bay
0.708 Chipps m 73 95% C.l. ~ ~SIMld
Dclr:a
en D.7C7' - - - - - - - - - - - - - - -1'-- J
" ~fl-1\1.!1 t aJ J
aJ R ) "iri,;lHD b.i!Dt I
175 I
D.1DI r'oopor J
.... .- -- --- - -- --... f R . 1'1- ' I iJ 1 QLlrl·l~ 1 ,..:!-1fJ.!
0.705 567 ®dding .:: •.t.f].r:~ , .. i .1,-o.:ato
D.704
200 300 400 500 SOO 700 ,BOO 000
Distance rom otolith core (~m)
Delta rearing is likely, but difficult to discriminate isotopically from Feather River
0.709
0.708
0.707
0.706
0.705
0.704
{d) De~ ta or Feather R~ver
i
L • • - • •
... -
Bay
Do/ra
ather Ri'WJr
Sacramento RiiiCt
200 300 400 500 SOO 700 ,BOO 000
0
73
567
Distance rom otolith core (~m)
Loeatia
Gold£: Gate
Chipps ~SIMld
®dding
Sr oonoo tration
9o 95% C.l.
" ~fl-1\1.!1 t aJ R ) "iri,;lHD b.i!Dt
---------- .......... ---
J
J
I
I
J
45-65% of adults reared in non-natal habitats as juveniles
Q2: Are both fry and parr migrants represented in the adult population?
Spatial diversity in rearing strategies
Temporal diversity in rearing strategies?
fry (<55mm)
parr (55-75 mm)
smolt (>75 mm)
leave earlier
leave later
Otolith radius
Fork length
Zabel et al., 2010
Otolith radius is a suitable proxy for body length, but it varies by ESU
***Currently no established relationship for SWRC ESU***
Fork length ~ f(Otolith radius + ESU)
Lots of variation in migration timing between individuals
Body size was estimated at exit from the natal rearing habitat
Natal rearing exit size
Fry migrate to non-natal rearing habitats
Freshwaterexit size
Q3: Are there differences in size at freshwater exit associated with juvenile rearing habitat?
Size at freshwater exit is conserved across rearing habitats…
…But freshwater exit size differs across years
10-year winter-run otolith study spanning hydroclimatic regimes
Q1: Where do the successful winter-run rear as juveniles?
A1: Winter-run rear in the Sacramento and Delta. But they also use non-natal habitats
Q2: Are both fry and parr migrants represented in the adult population?
A2: Yes, and the non-natal habitats are used successfully by fry
Q3: Are there differences in size at freshwater exit?
A3: Freshwater exit size is conserved across rearing habitats, but can vary between years
In summary:
Lessons from t'h:e Ocean for Integrating Science in Policy Decisions Steve Gaines, Dean, Bren School of Environmental Science and Management at UCSB
The Scientific C allenges of Establishing Appropriate Baselines for Watershed Restoration Daniel Schindler, Harriet Bullitt Endowed Chair in Conservation, School of Aquatic and Fishery Sciences, University of Washington
Ecosystems are not static. They are reshuffling in response to
physical and biological drivers.
Populations are resilient when there are options to reshuffle into
For winter-run, non-natal rearing habitats are some of those options
Incorporate non-natal rearing habitats into our conceptual models
Narrative model Life-Cycle Model
Non-natal habitats represent options for fish
But they also represent management options
Conservation Value
Stak
ehol
der V
alue
scenarios in critical habitat onlyscenarios that include non-natal habitat
efficiency frontier
Non-natal habitats represent options for fish
But they also represent management options
Conservation Value
Stak
ehol
der V
alue
scenarios in critical habitat onlyscenarios that include non-natal habitat
efficiency frontier
Acknowledgements
Otolith samplesUSFWS & Livingston Stone FH staff
Otolith preparation & analysesJustin Glessner & George Whitman
FundingCALFED(!!!)
Delta Science Program MWD
YearOctNovDecJanFebMarApr
MayJunJul
AugSep
1993 2016
Fremont weir overtopping event
http://www.cbr.washington.edu/sacramento/data/alert_weirs.html
Timing and duration of Yolo Bypass inundation varies year-to-year
YearOctNovDecJanFebMarApr
MayJunJul
AugSep
1993 2016
Fremont weir overtopping event
http://www.cbr.washington.edu/sacramento/data/alert_weirs.html
Yolo bypass is rarely accessible when fry need rearing habitat
2007 2008 2009
RBDD RST
Knights Landing RST
Date cumulative catch exceeded ~80% at:
Chipps Island Trawl
del Rosario et al., 2013
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