Atlantis Modelling of the Upper Gulf of California: EBM support for

Transcription

Atlantis Modelling of the Upper Gulf of California: EBM support for
Cameron Ainsworth
Northwest Fisheries Science Center (NOAA)
Seattle, WA
PICES Annual Meeting. Portland, OR. Oct. 2010
Samhouri, J.F., Ainsworth, C.H., Busch, D.S., Cheung, W.L., Okey, T.A.
West Coast
Vancouver
Island Aquatic
Management
Board
Trilogy of papers
How will climate change impact marine ecosystems in the NE Pacific?
NE Pacific study area
• Prince William Sound (PWS)
• Southeast Alaska (SEA)
• Northern British Columbia (NBC)
• West Coast Vancouver Island (WCVI)
• Northern California Current (NCC)
Review of 1st paper
• 5 climate effects simulated using
increased or decreased organism
productivity (Ecosim forcing functions)
• 3 levels of severity tested
• Impacts tested alone and in combination
(additive)
Ocean acidification
Species range shifts
Cheung et al. 2009 (Fish and Fisheries)
Plankton size structure
Deoxygenation
Primary productivity
Ecopath with Ecosim
Model
Northern British Columbia
Northern California Current
Prince William Sound
Southeast Alaska
West Coast Vancouver Island
# groups
53
65
48
40
15
Reference
Ainsworth 2007
Field et al. 2006
Okey and Pauly 1999
Guenette et al. 2006
Martell 2002
Polovina, J.J., 1984. Coral Reefs, 3 (1): 1–11. ··· Christensen, V., Pauly, D., 1992.. Ecological Modeling, 61: 169–185. ··· Walters, C.,
Christensen, V., Pauly, D. 1997. Reviews in Fish Biology and Fisheries, 7: 139-172.
Ecopath with Ecosim
n
n
dBi
= c g i ∑ f (B j , Bi ) − ∑ f (Bi , B j ) + I i − Bi (M i + Fi + ei )
dt
j =1
j =1
Production
Predation
losses
Fisheries and
other mortality
Ecopath master equations
n
Mass balance: Bi ⋅ ( P / B )i = Yi + ∑ B j ⋅ (Q / B) j ⋅ DC ji + Ei + BAi + Bi ( P / B) i ⋅ (1 − EEi )
j =1
Conservation of energy: B ⋅ (Q / B) = B ⋅ ( P / B) + (1 − GS ) ⋅ Q − (1 − TM ) ⋅ P + B ⋅ (Q / B) ⋅ GS
Ecopath: Polovina, J.J., 1984. Coral reefs, 3(1): 1-11. Christensen, V. and D. Pauly, 1992. Ecological Modeling, 61: 169-185.
Ecosim: Walters, C., V. Christensen and D. Pauly, 1997. Reviews in Fish Biology and Fisheries, 7: 139-172.
Ecopath with Ecosim
n
n
dBi
= c g i ∑ f (B j , Bi ) − ∑ f (Bi , B j ) + I i − Bi (M i + Fi + ei )
dt
j =1
j =1
Annual scalar multiplier of biological production
Dissolved oxygen forcings (NBC)
Range shift forcings (NBC)
1st paper: Individual climate effects
Range shifts
bring rockfish
north and
reduce
competition
for plankton
Ocean
acidification
not good for
calcified
organisms
1st paper: Cumulative effects
Less catch overall
More low-value species
jellyfish
dogfish
ratfish
Doesn’t include human opportunism
Now the current study
Do community interactions change our predictions?
Range shifts
• Used bioclimatic envelope model (Cheung et al. 2009) to predict
relative abundance of fished species in 0.5° x 0.5° grid
• Predicts distribution based on species’ environmental preferences
• Based on ocean temperature, salinity from GFDL coupled model 2.1
2010
2060
0
0
Low
>
Relative
abundance
>
>
>
>
>
>
>
High
>
Pacific hake
How we simulated range shifts
Bioclimatic
envelope model
predictions
Biomass
(a focal species)
Trophic
interactions
change the
‘single species’
trajectory
Recreated
using forcing
functions
All range shifts
simultaneously
Year
Range shifts
*
Range shifts in Northern BC
Did we
get it right?
Relative abundance
2.5
2.0
1.5
1.0
0.5
0.0
2000 2010 2020 2030 2040 2050
Year
*Predicted by Cheung et al (2009) model in Ainsworth et al (2010)
Coho salmon
Chinook salmon
Squid
Ratfish
Dogfish
Forage fish
Eulachon
Adult herring
Adult POP
Rockfish
Flatfish
Adult halibut
Adult Pacific cod
Adult sablefish
Adult lingcod
Shallowwater benthic fish
Skates
Large crabs
Commercial shrimp
Some species increase,
some decrease
Range shifts
Did we get it right?
Not bad
No change
22%
Increase
17%
Decrease
61%
•
Cheung’s single species
methodology is
recreated here by
holding other groups
static
(no trophic interactions)
Range shifts
small pelagics
rockfish
No change
22%
Increase
17%
pelagic invertebrates
large pelagics
NBC
flatfish
elasmobranchs
Decrease
61%
demersals
benthic invertebrates
-40 -20 0
20 40 60
% difference vs. baseline
Single species trajectory
NCC
SEA
Range shifts
small pelagics
rockfish
No change
No change
22%
36%
Increase
17%
Increase
pelagic invertebrates
35%
large pelagics
NBC
flatfish
elasmobranchs
Decrease
29%
61%
demersals
benthic invertebrates
-40 -20 0
20 40 60
% difference vs. baseline
Now with all range shifts
NCC
SEA
Findings
•
Community interactions might moderate
range shifts across a wide range of
exploited functional groups
Ocean acidification
Functional groups affected
L
S
S
Northern British Columbia
Commercial shrimp
Epifaunal invertebrates
Euphausiids
L
S
S
L
Northern California Current
Benthic shrimp
Euphausiids
Infaunal invertebrates
Pandalid shrimp
S
L
Southeast Alaska
Carnivorous epibenthic invertebrates
Shrimps
2
Productivity
Effect
size
1870
1870
Linear forcing to
-10% or -50%
S
1
Aragonite
Aragonite
saturation
saturation 2060
2060
ND
ND
Low
Low
L
0
Marginal
Marginal
Adequate
Adequate
Optimal
Optimal
2010
2035
2060
Year 2008
Guinotte & Fabry
Guinotte & Fabry 2008
Guinotte, J.M, and Fabry, V.J., 2008. Ocean acidification and its potential effects on marine ecosystems. In: Ostfeld, R.S., Schlesinger, W.H. (Eds.), The Year in
Ecology and Conservation Biology 2008, Annals of the New York Academy of Sciences, pp. 320–342.
Ocean acidification
Manipulated groups only
No change
39%
Decrease
61%
(manipulated groups
and other groups)
Single species trajectory
Manipulated groups only
Ocean acidification
Manipulated groups only
No change
39%
Manipulated groups only
Decrease
61%
(manipulated groups
and other groups)
Now with all OA effects
Multispecies effects reduce impacts on invertebrates
relative to single-species expectations
Ocean acidification
Benthos under multispecies impacts
10.00%
4
Biomass (t/sqkm)
Groups that depend on benthos
p<0.01
8.00%
3
6.00%
2
4.00%
1
2.00%
0
0.00%
p~0.2
p<0.01
‐2.00%
‐1
‐4.00%
‐2
‐6.00%
NBC
NCC
SEA
NBC
NCC
SEA
Multispecies
OA
Theseimpacts
groups alleviate
are responding,
effects on
butbenthos
not how you would expect
Makes them worse
Findings
•
Community interactions may reduce
OA impacts on affected
invertebrates
•
Effects do not cascade up the food
web as expected
Primary production
NCC
NBC
15%
20%
Anomaly
20%
10%
10%
5%
0%
0%
‐10%
‐5%
‐20%
‐10%
2010 2020 2030 2040 2050 2060
Year
2010 2020 2030 2040 2050 2060
Year
y
30%
20%
15%
10%
5%
0%
‐5%
‐10%
‐15%
SEA
2010 2020 2030 2040 2050 2060
Year
• Geophysical Fluid Dynamics Laboratory (GFDL) Earth
System Model (ESM2.1)
• Includes Tracers of Ocean Phytoplankton with Allometric
Zooplankton (TOPAZ) model of ocean ecosystems and
biogeochemical cycles
• Simulations based on the IPCC AR4 protocols (SRES A1B).
Primary production
NCC model
80
phytoplankton
70
Vs. GFDL predictions, variability of
Phytoplankton
variability
decreased
phytoplankton
has increased
6% 15%
60
50
zooplankton
40
Zooplankton variability decreases 8%
30
20
10
0
2010
2020
2030
2040
2050
Compensatory feeding dynamics by high TLs reduce variation in plankton
Zooplankton
4 month lag
with phytoplankton
(R = 0.74)
NCC:show
Zooplankton
variability
decreases 8%
NBC: Zooplankton variability decreases 1%
Foraging arena: Walters, C.J. and F. Juanes, 1993. CJFAS, 50: 2058-2070.
Primary production
Findings
•
Multispecies interactions increase
variability of phytoplankton
•
Higher TL interactions reduce
variability of prey
Summary
Do community interactions change our predictions?
• Range shifts and ocean acidification impacts
are moderated by multispecies interactions
• Variability of primary production increases
Thank you

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