Generating scenarios of salmon recovery: what are the mechanisms linking climate

variability to marine survival?

E. Logerwell1, N. Mantua2, P. Lawson3,

R. Francis4 and V. Agostini4

1Alaska Fisheries Science Center

2 Univ. Washington School of Marine Affairs/Joint Institute for the Study of the Atmosphere and Ocean

3 Northwest Fisheries Science Center

4 Univ. Washington School of Aquatic and Fisheries Science

Salmon and Climate

Mantua, et al. 1997

Pacific Decadal Oscillation Index

above average

below average

#

Columbia River

Newport

Oregon

Washington

California40° 40°

41° 41°

42° 42°

43° 43°

44° 44°

45° 45°

46° 46°

47° 47°

48° 48°

49° 49°

127°

127°

126°

126°

125°

125°

124°

124°

123°

123°

122°

122°

121°

121°

Oregon Production Index (OPI) Coho Salmon

OPI Coho Survival

0.00

0.02

0.04

0.06

0.08

0.10

0.12

0.14

1969 72 75 78 81 84 87 90 93 96 99Year (ocean entry)

Sur

viva

l (pr

opor

tion

)

Previous studies link coho survival to ...

• Upwelling (Nickelson, 1986)

• Sea surface temperature (Cole, 2000)

• Spring transition (Ryding & Skalski, 1999)

• Spring and winter ocean conditions (Koslow, et al. in press)

• Select variables that represent local nearshore conditions

• GAM to understand effects of ocean processes on survival

• Examine linkages between model variables and climate indices

Our study of coho survival

Conceptual model

Spring transitiondate

Water column stratification(influenced by winter climate)

Spring/Summerupwelling winds

1st Winterocean feeding

Smolt migration

Feeding and predatoravoidance

Overwintermortality

Coho early marine life history

Environmental bottlenecks

2 4 6 8 10 12 14

-1000 mb

0.00

0.04

0.08

0.12

Sur

viva

l

NPI

60 80 100 120 140 160

Julian Day0.

000.

040.

080.

12

Sur

viva

l

Spring transition*

0 20 40 60

m^3/s/100 m

0.00

0.04

0.08

0.12

Sur

viva

l

Upwelling*

2 4 6 8 10 12 14

-1000 mb

0.00

0.04

0.08

0.12

Sur

viva

l

NPI

-100 -80 -60 -40 -20 0

m^3/s/100 m

0.00

0.04

0.08

0.12

Sur

viva

l

Upwelling*

10.5 11.0 11.5 12.0 12.5

degrees C

0.00

0.04

0.08

0.12

Sur

viva

l

SST

-100 -80 -60 -40 -20 0

m^3/s/100 m

0.00

0.04

0.08

0.12

Sur

viva

l

Upwelling

9 10 11 12

degrees C

0.00

0.04

0.08

0.12

Sur

viva

l

SST*

-150 -100 -50 0 50

mm

0.00

0.04

0.08

0.12

Sur

viva

lSea level*

9 10 11 12

degrees C

0.00

0.04

0.08

0.12

Sur

viva

l

SST*

Winter (Jan-Mar) before smolt migration

Spring (April-June)

Winter (Jan-Mar) after smolt migration

Transition

GAM Results

0.00

0.02

0.04

0.06

0.08

0.10

0.12

0.14

1969 72 75 78 81 84 87 90 93 96 99Year (ocean entry)

Sur

viva

l (pr

opor

tion

) ObservedPredicted

Climate linkages

• Indices– NPI (Aleutian Low)– PDO– ENSO

• 1948-1997

• October-March

NPI (Aleutian Low)Spring upwelling

Spring transition

Winter SST (after)

Winter SST (before)

PDOWinter SST (after)

Spring upwelling

Spring transition

Winter SST (before)

ENSOWinter SST (after)

Spring upwelling

Spring transition

Winter SST (before)

How might recovery scenarios affect salmon?

• Life stage? – marine survival

• Habitat characteristics? – winter SST, spring transition, spring upwelling

• Forecasts? – climate linkages between NPI, PDO and pre-

smolt winter SST

Uncertainty?

• Biological dimension of ocean habitat– Predators? – Prey?

• Climate forecasts– Natural variability (El Niño, PDO, other)– Anthropogenic change

Alternative scenarios?

Can we make a similar forecast for ocean variables (such as SST) or climate variables (such as NPI)?

Beth Sinclair and Tonya Zepplinhttp://nmml.afsc.noaa.gov/AlaskaEcosystems/sslhome/Program%20Review%20Presentations/Program%20Review.htm