Salmon and society: Lessons from the Pacific Northwest

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Salmon and society: Lessons from the Pacific Northwest. Robin Waples Northwest Fisheries Science Center National Marine Fisheries Service N.O.A.A Seattle, WA USA. Subtext: Tell us how you #@&%ed it up down there so we will feel better [and, perhaps, can avoid the same problems]. - PowerPoint PPT Presentation

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Salmon and society:Lessons from the Pacific Northwest

Robin Waples

Northwest Fisheries Science Center

National Marine Fisheries Service

N.O.A.A

Seattle, WA USA

Subtext:

Tell us how you #@&%ed it updown there so we will feel better

[and, perhaps,can avoid the same problems]

Numberof stocks

Special Concern 54 Moderate Extinction Risk 58High Extinction Risk 101Extinct <100

Pacific salmon stocks at riskNehlsen et al. 1991

0

1

2

3

4

5

6

1970 1975 1980 1985 1990 1995

Year

Millions of fish

Calif

Oregon

Wash

Total

Coho salmon landings

ocean troll & sport fisheries

Status review scorecard Not

Species E T C Listed

Chinook 2 7 1 7Chum - 2 - 2Coho - 3 2 1Cutthroat - (1) 1 4Pink - - - 2Sockeye 1 1 - 5Steelhead 2 8 2 3

Totals 5 22 6 24

Cultural, economic, spiritual reasons

Loss of population diversity limits evolutionary potential of the species

Life history diversity • Promotes efficient use of natural resources

• Buffers productivity

Keystone species in terrestrial (and marine) ecosystems

Why is salmon conservation important?

Upstream: National ResearchCouncil 1996

General conclusion:“The long-term survival of salmon depends crucially on a diverse and rich store of genetic variation.”

There are plenty of salmon in Alaska

Salmon are colonizing species

Salmon have plastic life-history features

Common counterarguments

"singularly unsuccessful in producing new anadromous stocks”

Stock transfers of Pacific salmon:

Withler 1982

Stock transfers of O. nerka:

Percent successful

Kokanee 90

Sockeye <5

Wood 1995

Risk/recovery factors for Pacific salmon

• Habitat• Harvest• Hatcheries• Hydropower

• Misc (e.g., invasive species; natural variability)

214 Pacific salmon stocks at riskNehlsen et al. 1991

Primary factors for decline:

Habitat loss/degradation 92%

Overharvest 49%

Hatchery interactions 49%

Habitat requirements for Pacific salmon

• Ample, high quality water

• Aerated spawning gravels

• Juvenile rearing areas

• Unimpeded migration routes

Skagit River Basin

Historical habitat

Percent change

Sloughs Side channel DistributaryTributaries Hydromodified Nonhydromodified Above culverts Above damsMain stemLakes

860,100 m2

431,200 m2

283,500 m2

463,600 m2

124,200 m2

43,400 m2

632.4 km735 ha

-45%-64%

-15%-23%

-100%-100%

-7%+404%

Habitattype

Beechie et al. 1994

Historical changes in habitat of Puget Sound estuaries

0

2,000

4,000

6,000

8,000

10,000

Acres

NooksackLummiSamishSkagitStillaguamishSnohomishDuwamishPuyallupNisquallySkokomishDungeness

Historical

Present

40

30

20

10

00 60302010 40 50

Biotic integrityCoho/Cutthroat Ratio

Bio

tic

Inte

gri

ty

Watershed urbanization (%TIA)

Horner and May 1998

2

4

6

Mean number of years between 5-year flood events

Pristine 5

Urbanized 1.1

Booth 1991

Human Population Growth in Pierce, King, and Snohomish Counties, 1860-1990

0

200,000

400,000

600,000

800,000

1,000,000

1,200,000

1,400,000

1,600,000

186018701880 189019001910 192019301940 1950196019701980 1990

King

Pierce

Snohomish

Some dam impacts

are obvious

0

5000

10000

1955 1960 1965 1970 1975 1980 1985 1990 1995 2000

Number of redds

Snake River spring/summer chinook salmon redds

Snake RiverDam construction

Others only appear to be obvious

-2.000

-1.500

-1.000

-0.500

0.000

0.500

1.000

1.500

2.000

2.500

19651968197119741977198019831986198919921995

Stanardized anomaly

Ocean conditions (PDO) have shifted

Good Poor

Hydropower system completed

60 62 64 66 68 70 72 74 76 78 80 82 84 86 88 90 92 94 96 980.0

0.2

0.4

0.6

0.8

1.0

Outmigration Year

Juve

nile

Sur

viva

l in

Hyd

rosy

stem

from Raymond 1988

Williams et al. 2001

•No data•Fish passage improvements

Other impacts are less clear

Snake River spring/summer chinook smolts

0

10

20

30

40

50

60

1870

1880

1890

1900

1910

1920

1930

1940

1950

1960

1970

1980

1990S

alm

on

lan

din

gs

(mill

ion

s o

f p

ou

nd

s)

1935 Fishwheelsprohibited

1950 Seines,traps, set nets prohibited

1965 LastSummerseason

1977 Lastspringseason

1988 Last sockeyeseason

Columbia RiverSalmon harvest

Recruits

Spawners

MSY

Replacement

Spawners

Snake River Steelhead

0

50,000

100,000

150,000

1960 1970 1980 1990

Ad

ult

Ru

n S

ize

Total

Natural

Long-term sustainability unproven• Catastrophic failure

• Political and funding uncertainties

• Erosion of ecological/genetic/life history diversity

• Loss of fitness and productivity

Hatcheries don’t promote functioning natural ecosystems

Why is it important to conserve wild salmonids--what about hatcheries?

Hatchery vs. wild environments

Similarities Water

Differences Food Substrate Density Temperature Flow regime Competitors Predators

2.00

1.60

1.20

0.80

0.40

0.00

-0.400 25 50 75 100

Oregon steelhead

LocalNon-LocalExpected

From Chilcote 1998

Pro

du

ctiv

ity

Percent hatchery 25

10 20 30 40 5010 20 30 40 50-3

-2

-1

0

1

2

Sur

viva

l wild

chi

nook

(lo

g)

Number of hatchery spring chinook released (millions)

r2 = 0.06 r2 = 0.73

Average Ocean Productivity Poor Ocean Productivity

Levin et al. 2001

Risks

Benefits

Types of benefits to be considered

• Natural pops

• Harvest

• Mitigation

• Treaty obligations

• Public education

• Natural pops

Conservation General

Supplementation review

Was it met?Objective Y N ?

Broodstock collection (representative) Age 11 3 8Run timing 10 2 10Integrity 17 5 -

Hatchery survivalPrespawning (90%) 12 6 4Egg-smolt (70%) 19 2 1Adult-adult (2x) 12 4 6

Population increase (20%) 8 11 3Natural spawning (comparable) 1 2 19Sustainable - 2 20

Waples et al. in press

How insulated are wilderness areas from external impacts?

A by-product of the life cycle

• Most biomass of salmon is acquired at sea

• Results in a transfer of marine nutrients to terrestrial systems

Adult spawners Directly consumed by cohort of 2000

Could indirectly affect salmon by fueling 1o and 2o production in streams

Native rangeIntroduced

Brook Trout Salvelinus fontinalis

Brook trout absent

0 500 1000 1500

Juvenile chinook density

0.0

0.1

0.2

0.3

0.4

0.5

Ch

ino

ok

surv

ival

0 500 1000 1500

Brook trout present

Achord et al. 2003

Percent Extinct

0

10

20

30

40

50

60

PinkChum

Sock

Coho

ChinSteel

Pink

Chum

Sock

Coho

Chin Steel

PinkChum

Sock

Coho

Chin Steel

Pink

Chum

SockCoho

ChinSteel

Ecology LifeHistoryGenetics ESUs

Gustafson et al. in prep

c: Population Size

b: Ocean Environment

a: Freshwater Habitat Quality

=

+

DCB

A

Time

Escapement0 Lawson 1993

Oregon coast coho

0

2

4

6

8

10

1969 1972 1975 1978 1981 1984 1987 1990 1993 1996

Sm

olt

-ad

ult

su

rviv

al (

%)

Year

Oregon coast coho -- Rivers

10000

100000

1000000

1965 1970 1975 1980 1985 1990 1995 2000 2005

Abundance

Pre-Harvest RecruitsSpawners

Vertical slides here

Percent Extinct

0

10

20

30

40

50

60

PinkChum

Sock

Coho

ChinSteel

Pink

Chum

Sock

Coho

Chin Steel

PinkChum

Sock

Coho

Chin Steel

Pink

Chum

SockCoho

ChinSteel

Ecology LifeHistoryGenetics ESUs

Gustafson et al. in prep

1) Puget Sound 32) Willamette/LCR 5 3) Interior Columbia 74) Oregon Coast 15) S. Oregon/N. CA 16) North-central CA 37) South-central CA 28) Central Valley 3

Total 25

Listed ESUsDomain

A B C

Which ESUs are viable?

X

X

X

X

X X

XX XX

Risk

High Medium Low

Total 3 5 11

North 2 3 7South 1 2 4

Summer 2 2 0 Winter 1 3 11

Wild 3 3 2Hatchery 0 2 9

Diversity

Conclusions• Causes of salmon declines can be complex

–FW habitat most pervasive threat–Habitat problems are caused by people–Habitat that appears pristine may not be

• Salmon populations generally are not replaceable on ecological time scales• Long-term effects of hatcheries on natural populations are uncertain but

may be profound• In PNW much has been lost, but much remains. Region is at a pivotal point• Fluctuating ocean cycles + declining FW productivity = trouble for salmon

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