COMPARATIVE SURVIVAL STUDY Chapter 3: Annual SAR by study category and ratios of SARs

1. COMPARATIVE SURVIVAL STUDY Chapter 3: Annual SAR by study category and ratios of SARs Evaluate effectiveness of smolt transportation relative to other passage routes through dams and reservoirs • Comparisons of SARs • Transport to In-River • By hatchery group • Hatchery to Wild • Sp/Su Chinook to Steelhead

2. Snake River spring/summer Chinook and steelhead • Wild Chinook • Aggregate Snake (above LGR) • Hatchery Chinook • DWOR • RAPH • MCCA • IMNA • CATH - AP • Wild Steelhead • Aggregate Snake • Hatchery Steelhead • Aggregate Snake

3. Definitions • SAR = LGR adults / LGR smolts • TIR = SARtransport / SARinriver • T0 = category of smolts transported from LGR, LGS or LMN, number of smolts expressed in LGR equivalents • C0 = category of smolts migrating through the hydrosystem that were not collected at transport projects LGR, LGS or LMN, in LGR equivalents • C1 = category of smolts migrating through the hydrosystem that were collected and bypassed at one or more of transport projects

4. SARs: Wild Chinook showed no benefit from transportation (on average) • Exception in extreme drought year 2001 • SAR = LGR adults/LGR smolts

5. SARs: Wild steelhead benefited from transportation (on average) • Benefit is relative • In-river conditions less than optimal (e.g., before court-ordered spill) • Wide CI before 2003

6. In-river SARs: Wild Chinook > Hatchery Chinook • Transport SARs: Some Hatchery SARs > Wild SARs In-river SAR Transport SAR

7. Transport beneficial Transport detrimental • SAR ratios: SAR(Transport) / SAR(In-river) = TIR • Hatchery Chinook - relatively more benefit from transportation than wild • TIR generally positive for hatchery populations (MCCA > RAPH > DWOR) • TIR slightly negative for wild populations (except 2001)

8. transport transport transport transport Adult upstream migration survival (BON – LGR) is also affected by the juvenile migration experience. Hatchery Chinook Wild Chinook • ~10% lower adult migration success for LGR transport compared to LGS/LMN transport or in-river migration • Implication for straying of transported fish into other populations

9. Conclusions: Annual SAR by study category and ratios of SARs • Wild Chinook – no benefit from transportation (on average) • Hatchery Chinook - relatively more benefit from transportation than wild; varied among hatcheries • Wild and hatchery steelhead – relative benefit from transportation; wide CI • Relative transport benefit greater in extreme drought year (2001) with poor in-river conditions • Transported wild and hatchery Chinook and steelhead smolts died at greater rate in estuary and ocean than in-river migrants (D < 1) • Process of collection/bypass compromised SARs: C1 < C0 in wild and hatchery Chinook and steelhead • Transportation from LGR reduced adult upstream migration success (straying/mortality)

11. COMPARATIVE SURVIVAL STUDY Chapter 5: Evaluation and Comparison of Overall SARs Do SARs meet regional goals? Are Snake River SARs similar to downriver SARs?What management and environmental factors influence SARs? • Comparisons of SARs • NPCC 2% - 6% SAR goal • Snake vs. John Day wild • Snake vs. Carson Hatchery • Multiple regression analyses

12. Overall SARs of wild Chinook and steelhead fell short of the NPCC 2-6% SAR objectives: • NPCC: 2% minimum, 4% average for recovery • Wild Chinook average = 0.8% • Wild steelhead average = 1.6%

13. Good precision - hatchery Chinook SARs Poor precision – aggregate hatchery steelhead SARs

14. Upriver / Downriver SAR comparisons

15. John Day R. Snake R. Snake River life-cycle survival rates declined with FCRPS Recent survival of Snake River Chinook ~ 1/3 to ¼ that of downriver Chinook CSS: Do we see similar magnitude of differential mortality in SARs? Can life history differences explain the differential shift in mortality? Schaller et al. 1999; Deriso et al. 2001; Schaller and Petrosky 2007

16. Snake River wild SARs ~¼ of John Day SARs • 8 dams vs. 3 dams • SAR data consistent with spawner-recruit analyses

17. Life history characteristics: Snake vs. John Day wild • No consistent, systematic differences in smolt size (FL) • Emigration timing from tributaries within a similar time frame (with greater variation for Snake) • Rate of emigration similar (1st to 3rd dam), a function of water velocity • Snake smolts estuary arrival timing ~ 7-10 days later than John Day smolts (a function of FCRPS) • When arrive to estuary at same time, Snake SARs are < John Day SARs • A “natural experiment”; weight of evidence

18. Multiple Regression Analysis: Historic Snake River ChinookSARs vs. smolt migration and ocean/climatic indices

19. Pacific Decadal Oscillation • Interdecadal climate variability in the North Pacific – (Sea Surface Temperature) • Coastal Upwelling Index • based upon Ekman's theory of mass transport due to wind stress - 45oN – (productivity) • “Good Ocean” • Cool phase PDO • April Upwelling • Oct Nov Downwelling Coastal Upwelling Process

20. Water Travel Time: Lewiston to Bonneville DamWTT influences smolt travel time & reach survivalpre-dam ~2 days; current ~ 19 days (10-40 days) 1938 (BON), 1953 (MCN), 1957 (TDD), 1961 (IHR), 1968 (JDA), 1969 (LMN), 1970 (LGS), 1975 (LGR)

21. Pre-dam WTT Best fit (adj. R2=0.64), best 3 parameter model Current WTT Expected change in SARsvs. WTT, PDO & UpwellingWTT significant variable in all best-fit models i.e., Snake River SARs not just due to ocean condition Analysis does not use downriver populationsResponse to WTT - similar to results using upriver/downriver populations

22. Do PIT tag SARs represent SARs of the run at large? • Run reconstruction (RunRec) SARs slightly larger than point estimate PIT SARs • RunRec SARs fell within the 90% CIs of for 5 of 8 years • Unresolved issues with wild adult accounting for RunRec SARs: assessing bias is difficult • For analyses using ratios of SARs, issue is of little concern (e.g., upriver/downriver, transport/in-river)

23. CSS – New Analytical Tools • Bootstrap CI methods for SARs, ratios of SARs (Ch. 3) • Method to estimate central tendency of SARs, & ratios of SARs accounting for large inter-annual variation and variable sample sizes (Ch. 4) • Within year differences of TIR – i.e., when is it best to transport? • Potential for looking at SAR differences between groups over multiple years with small or variable sample sizes • Simulation model to investigate potential bias in CJS survival estimates due to assumption violations (Ch. 7) • CJS parameter estimates are robust in the presence of within-season changes in survival or detection probabilities

24. Conclusions • Different responses of wild Chinook and wild steelhead to transportation: • maximization of survival of both species cannot be accomplished by transportation as currently implemented. • Improvements in in-river survival: • can be achieved through management actions that reduce the water travel time or increase the average percent spilled. • the effectiveness of these actions varies over the migration season. • Higher SARs of Snake River wild yearling Chinook were associated with: • faster water travel times during juvenile migration through the FCRPS, • cool broad-scale ocean conditions, • and near-shore downwelling during the fall of the first year of ocean residence.

25. Other management uses of CSS PIT-tag groups: • Idaho in-season Chinook harvest management: • run size • run timing • upstream conversion rates • Survival - release to LGR • SARs from LGR smolt to LGR adult • McCall, Rapid River, Dworshak Imnaha and Catherine Cr. hatcheries only • LSRCP programmatic and management needs for other Chinook hatcheries • LSRCP tagging initiated 2007, expanded 2008 in coordination with CSS • LSRCP steelhead tagging program • LSRCP tagging intiated 2008 in coordination with CSS