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Columbia River salmon: Who (or what) will save them? John Williams Klarälven meeting in Karlstad 9 May 2011

Columbia River salmon : Who (or what) will save them? John Williams Klarälven meeting in Karlstad 9 May 2011

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Columbia River salmon:

Who (or what) will save them?

John WilliamsKlarälven meeting in Karlstad

9 May 2011

Road Map

• Columbia River history• decline of salmon stocks• Endangered Species Act• detour - survival studies• recent trends• present controversies

The Players:• Dam operators (COE)• Power marketers (BPA and PUDs)• Water users (BuRec/irrigators/tow boats)• Environmental advocates• Native tribes• Fishers• States• Federal Government (regulators)• Federal Court system• Scientists• Mother nature

Science--range of results for different options Science--will not resolve policy issues:

• recovery objective• acceptable risk for failure to achieve objective• burden of proof--on fish or status quo• allocation of impacts among constituencies: who pays

Conclusion

Causes of decline(anthropogenic)

• harvest• habitat• hydropower

(but need to consider all dams)

• hatcheries

Columbia River salmon - peak runs1,000s of fish

(After Chapman TAFS – 1986)

Chinook - Spring 400 - 500Summer 1,700 - 2,000Fall 1,100 - 1,250

3,200 – 3,750

Steelhead 382 - 449

Sockeye 1,915 - 2,253

190019010

250

500

750

1000

1250Steelhead

Chinook

3000

1940 1950 1960 1970 1980 1990 2000

*

Sockeye

**

Average peak catch late 1880s-early 1990s(after Chapman 1986 TAFS)

Year

Adu

lt ca

tch

(1,0

00s)

Mitchell Act - 1938

• Historic location• Present location

Historic Present

Bonneville

McNary Lower Granite

Snake River wild spring-summerChinook salmon

1965 1975 1985 1995 20050

25

50

75

100

125

Adult return year

To

tal

retu

rn (

1,00

0s)

Stocks listed

Hydropower damcompletion

Snake River

Endangered Species Act Status of West Coast Salmon & Steelhead (Updated July 1, 2009)

Sockeye Salmon (Oncorhynchus nerka)

1 Snake River Endangered

2 Okanogan River Not Warranted

3 Lake Wenatchee Not Warranted

Chinook Salmon (O. tshawytscha)

4 Upper Columbia River Spring-run Endangered

5 Snake River Spring/Summer-run Threatened

6 Snake River Fall-run Threatened

7 Lower Columbia River Threatened

8 Upper Willamette River Threatened

9 Middle Columbia River spring-run Not Warranted

10 Upper Columbia River summer/fall-run

Not Warranted

12 Deschutes River summer/fall-run Not Warranted

Coho Salmon (O. kisutch)

13 Lower Columbia River Threatened

Chum Salmon (O. keta)

14 Columbia River Threatened

Steelhead(O. mykiss)

15 Upper Columbia River Threatened

16 Snake River Basin Threatened

17 Lower Columbia River Threatened

18 Upper Willamette River Threatened

19 Middle Columbia River Threatened

Changed flow

Cumulativeturbine mortality

‘Gas bubbledisease’

Snake River Chinook salmon

0

5

10

15

20

25

30

35

40

Low flow Moderate flow High FlowSnake R. (995-1,505 m3·sec-1) (2,017-3,010 m3·sec-1) (3,010-5,028 m3·sec-1)

Columbia R. (4,005-5,028 m3·sec-1) (6,022-9,034 m3·sec-1) (10,028-14,034 m3·sec-1)

0

4

8

0

48

0

4

8

Tra

vel t

ime

(d

ays

)

0

100

200

300

400

500

600

15-A

pr

29-A

pr

13-M

ay

27-M

ay

10-J

un

24-J

un

8-Ju

l

22-J

ul

5-A

ug

19-A

ug

Flo

w (

kcfs

)1949-1954

1955-1964

1965-1974

1975-1984

1985-1994

1995-2004

Solutions to addressproblems1.Spill – fix conditions, more of it, surface routes 2. Install bypass systems3. Transportation

4. Hatcheries (?)5. Restore flow6. Decrease harvest

Hatchery

Wild

*

Hatcheries• Juvenile releases• Effects on wild spawners

Snake River stocksEstimated juvenile smolt survival

through hydropower system

1965 1970 1975 19800.0

0.1

0.2

0.3

0.4

0.5

0.6

0.7

1995 2000 2005 2010

Nodata

Chinook

Steelhead

Outmigration year

Estim

ated

sur

viva

l

Smolt survival estimationHistorically - freeze-branded fish, batch marked

estimated collection efficiencyexpanded count to obtain populationcompared populations at dams

At present - PIT-tags (radio or acoustic tags) identify individual fish

maximum likelihood estimation basedon Cormack, Jolly, Seber procedures

Smolt survival estimation

Single-Release of Tagged IndividualsTwo “recapture” occasions

Mark-Recapture Data = Possible PIT-Tag Detection Histories

Detection histories record outcome of series of conditionally independent events.Histories constitute multinomial sample.

Probability of each history depends on conditional survival and detection probabilities.

111 : S1P1110 : S1P1101 : S1(1-P1S1S1(1-P1

=S2p2P1

S2

P2

R

S1

•Many assumptions

•Some not met exactly

•Bias in survival estimates

Status of stocks at present

(empirical data)

1960 1975 1990 20050

1

2

3

4

5

6Petrosky et al.(2001)

Estimated SR wild spring-summer Chinook(catch + escapement)

2-oceanonly

Outmigration year

Sm

olt-

to-a

dult

retu

rn

Snake River wild spring-summerChinoook salmon

(based on ocean upwelling indices)

1964 1974 1984 1994 20040

1

2

3

4

5

forecast

Lower 90% PIUpper 90% PI

Observed(2-ocean only for 2006)

Outmigration year

Sm

olt

-to

-ad

ult

ret

urn

rat

es(%

)

R2 = 0.71

(after Scheuerell and Williams. 2005. Fish & Ocean)

1995 1996 1997 1998 1999 2000 2001 2002 2003 2004 2005 2006 2007 20080.0

0.5

1.0

1.5

2.0

2.5

3.0

3.5

4.0

4.5

Snake River wild Chinook salmon (LGR to LGR)

Unmarked

PIT-tag

Year of outmigration

Sm

olt-

to-a

dult

retu

rn r

ate

(%)

Some return rate arguments based on PIT-tagged fish

But, absolute numbers of wildfish returns less

What will happenin the future?

Karluk Lakeδ15N

Anchovyscales

Sardinescales

Saanich fishremains

0 400 800 1200 1600 AD2000 Calendar age

From Finney et al.(2002). Nature

It is difficult to know where to go, when we don’t know where we are.

Actions planned• continue harvest limitations• consider decreasing hatchery production• improve spawning, rearing, and migration habitat• ‘tweak’ hydropower system

Summary• stocks declined concurrent with hydropower construction• direct juvenile survival now high• run timing of smolts critical • ocean influences return rates• hydropower now ‘takes’ some juveniles that historically would have become adult harvest• unclear how much improvement in habitat possible• unclear effect of hatcheries

• controversial -- environmental activists want dams removed -- federal judge tends to side with environmental activists – dams limit recovery -- effect of habitat and hatcheries ?? -- do not have means to predict future -- concerns about how climate will affect stocks -- effect of anthropogenic changes on productivity and abundance ??

Thanks for your attention

Comments?

Questions?