Title: Overview
1Overview
- Modeling to date
- Distribution of mortality
- Achieving improvements with specific actions
- Building scenarios
- Dealing with uncertainty some ideas
2Snake River Spring/Summer Chinook Life Cycle
4,000-5,000 eggs
2 spawners
120-151 1-year-olds to Lower Granite Dam
1-1.4 Migrants return to spawning grounds
95-119 Migrants Below Bonneville Dam (77
transported, 23 in River)
4-5 Youngsters To 2nd Birthday (Estuary Ocean)
2-3 Adults return to mouth of Columbia
3Rate of population change Accounting for
hatchery fish
1.10
1.00
0.90
Population Growth Rate
0.80
0.70
0.60
0.50
Snake River
Lower Columbia
Snake River Fall
Lower Columbia
Upper Columbia
Upper Willamette
Middle Columbia
Upper Willamette
Upper Columbia Spr
Hatchery fish reproductive success 1
Snake River Spr/Sum
Columbia River Chum
Chinook
Steelhead
Hatchery fish reproductive success 0
4- How can we give fish what they need to survive
and recover?
5Hydropower
6Improvements to hydropower system
- Past passage improvements
- Future options
- Passage improvements
- Flow and spill measures
- Dam breaching
7Past vs. current passage survival
Snake River spr/sum chinook
8Option 1 anticipated changes with passage
improvement
9Harvest maximum benefits
10- Are there life stages at which management actions
might be most fruitfully aimed?
11Sensitivity Test Standard
reductions in mortality
12Snake River Spring/Summer Chinook Life Cycle
4,000-5,000 eggs
2 spawners
120-151 1-year-olds to Lower Granite Dam
1-1.4 Migrants return to spawning grounds
95-119 Migrants Below Bonneville Dam (77
transported, 23 in River)
4-5 Youngsters To 2nd Birthday (Estuary Ocean)
2-3 Adults return to mouth of Columbia
13Survival vs. sedimentation
14(No Transcript)
15Hatchery Genetic concerns
- Inadvertent selection due to hatchery practices
reduces fitness of hatchery fish. Interbreeding
of hatchery and wild fish may affect fitness of
wild fish as well. - Domestication seen in as little as a single
generation - Stock transfers
16Hatchery Ecological concerns
Average Ocean Productivity
Poor Ocean Productivity
r2 0.06
r2 0.73
Percent survival wild chinook (log)
10
20
30
40
50
Number of hatchery spring chinook released
(millions)
17Building scenarios
- Combinations of actions when one isnt enough
- Interactions between actions
- Continuing degradation in habitat/other
environmental factors
18Major areas of uncertainty
- Hatchery fish masking what is the TRUE
population status? - Interactions between life stages does
survival/growth/experience in one stage affect
survival/fitness in another? - Impacts of particular actions
19Snake River Spring/Summer Chinook Life Cycle
4,000-5,000 eggs
2 spawners
120-151 1-year-olds to Lower Granite Dam
1-1.4 Migrants return to spawning grounds
95-119 Migrants Below Bonneville Dam (77
transported, 23 in River)
4-5 Youngsters To 2nd Birthday (Estuary Ocean)
2-3 Adults return to mouth of Columbia
20Some possible approaches
- Different questions
- What actions (or areas) are important REGARDLESS
of the potential future? - Are there easy actions that might be useful for
bet-hedging against an unlikely future? - Which pieces of information would be most
important to have (would help us reduce our
uncertainty)?