Supplementary Methods and Results Section

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Electronic Supplementary Material for:

“Potential consequences of climate change for primary production and fish production in large marine ecosystems”

Julia L. Blanchard 1,2* , Simon Jennings 3,4 , Robert Holmes 5 , James Harle 6 , Gorka Merino 5 , Icarus

Allen 5 , Jason Holt 6 , Nicholas K. Dulvy 7 & Manuel Barange 5

A. Model Equations and Parameters

Table S1. Equations for the dynamic coupled size-spectrum model. Subscripts: i  {P = pelagic predators, B = benthic detritivores} and D=detritus

Equations Units

Dynamical system:

N

 t

P

N

 t

B

 m

 m

( G

( G

P

N

P

B

N

B

)

)

Temperature effect: t = e c 1

-

E /( kT )

D

P

D

B

N

P

N

B

Feeding rates result from allometric search rates, prey size preference and availability across the size spectra:

F

Pi

( m , t )

= tw i

A

P m a

P

ò

f ( m m

)

' N i

( m ', t ) m ' d m '

F

B

( m , t )

= t

A

B m a

B B

D

( t ) m -3 yr -1 g -1 m -3 yr -1 g -1 g yr -1 give growth rates:

G

P

G

B

( m , t )

=

K

P

( m , t )

=

K

B f f

PP

( m , t )

+

K

B

B

( m , t ) f

PB

( m , t )

Flux terms from death included: g yr -1 yr -1

Predation mortality

D iP

( m , t )

= w i

A

P

ò

m ' a

P j ( m ' m

)

N

P

( m ', t ) dm '

Intrinsinc and senescence mortality

D iO

( m )

= t

0.2

m

-

0.25

+

0.2

( m m s

)

0.3

Fishing mortality

F ( m )

=   í

F

 ,  m

  >  1.25

0  ,  otherwise yr -1 yr -1

Total death rates were:

D i

( m , t )

=

D iP

( m , t )

+

D iO

( m ) 

+  

F ( m )

Fishing mortality was only applied to the pelagic community where F was equal across all size > 1.25 g and the value of F was varied. yr -1

Table S2. Parameter definitions, values and units for the dynamic coupled size spectrum model. In cases where two values are given the first value is for pelagic predators and the second value is for benthic detritivores.

Symbol Definition Value Unit m min m

P,min minimum body mass of plankton minimum body mass of pelagic predators

10

10

-12

-3 g g m

B,min

(also of max body size of plankton) minimum body mass of benthic 10 -3.5

detritivores maximum body size in the whole system. 10 6 g m max g k

E c1

β

σ

Boltzmann constant activation energy constant preference for prey in either the pelagic or benthic spectrum preferred predator-prey mass ratio log10(PPMR) measure of the width of the log10 PPMR distribution pre-factor of search volume A



K exponent of search volume net growth conversion efficiency z z i

0 pre-factor for background mortality exponent for intrinsic background mortality start size for senescence mortality m s z s exponent for senescence background mortality

B. Model application and output

8.62E-5 eV K -1

0.63 eV

25.55

0.5

2.0

1.0

64, 6.4



0.2, 0.1

0.1

-0.25

1

0.3 m 3 kg

yr yr -1 g yr -1 g yr -1

-1

The plankton size spectrum is not modelled explicitly but has temporal dynamics that are driven by output from a coupled physical-biogeochemical model, POLCOMS-ERSEM. Temporal changes in the intercept of the plankton component of size-spectrum were estimated from phytoplankton and microzooplankton biomass density. The plankton size spectrum was described as log N(m) = a + blog(m) where N is abundance density per unit volume at mass, and mass is m (in grams). We estimate a from the total biomass density of phytoplankton and microzooplankton functional groups from the physical-biogeochemical model output by spreading the density across a realistic size range (10 -14 to 10 -4 g) and assuming a fixed slope

b of -1, in keeping with global empirical studies of phytoplankton size spectra [38]. Near sea floor detritus biomass density estimates from the physical-biogeochemical model were used

to force the detritus dynamics. Temperature estimates were taken form the mixed layer depth and near sea floor vertical layers for the pelagic predators and benthic detritivores, respectively.

The total biomass density (g m -3 ) across a size-range (m1=1 g to m2= 100 kg) was computed from the predicted numerical density at size N(m) at time across the continuum of body masses m as: m 2 m 1

ò

N ( m ) mdm

(1)

Similarly, the total fish production (g m -3 yr -1 ) was calculated from the growth rates at size

G(m) and the numerical density at size: m 2 ò m 1

G ( m ) N ( m ) dm

(2)

The total annual catch (or ‘yield’, in g m -3 yr -1 ) across a size-range was calculated by combining

(1) with the fishing mortality rate at size

F ( m )

: m 2 ò m 1

F ( m ) N ( m ) mdm

(3)

C. Details of the large regional marine ecosystem domains

Table S3. The large regional domains of coastal and shelf seas included in the analysis and the corresponding Large Marine Ecosystems (LME) that make up the domains, with information on the primary production, surface area and 2005 fish catches. These 28 LMEs contributed approximately 77% of the landed catch from all LMEs combined around the world, and 60% of the global marine landed catches.

PP Area Fish Catch 2005

Domain LME

Bengal Bay of Bengal

Benguela Benguela Current

(mgC.m

-2 .d

-1 )

729

1,387

(10 3 .km

2)

3,657

1,470

(t)

3,818,679

1,095,408

Canary

Guinea

Canary Current

Guinea Current

Humboldt Humboldt Current

Indo-

Yellow Sea

Pacific

Indo-

Pacific

Indo-

Pacific

South China Sea

Sulu-Celebes Sea

1,196

980

876

1,613

477

573

1,120

1,959

2,619

439

5,662,985

1,016

2,077,314

859,111

9,855,464

2,063,739

6,606,620

1,111,075

Indo-

Pacific

Indo-

Pacific

Indonesian Sea

Gulf of Thailand

NW Pacific East China Sea

NW Pacific Kuroshio Current

NW Pacific Okhotsk Sea

NW Pacific Oyashio Region

Sea of Japan/ East

NW Pacific Sea

NE Atlantic North Sea

NE Atlantic Celtic Biscay Shelf

NE Atlantic Faroe Plateau

NE Atlantic Iberian Coastal

NW

Atlantic

NW

Atlantic

NW

Newfoundland-

Labrador

NE US Continental

Shelf

Atlantic

Nordic

Nordic

Nordic

Nordic

Scotian Shelf

Norwegian Shelf

Icelandic Shelf

Greenland Sea

Baltic Sea

California California Current

California Gulf of California

772

780

891

422

815

716

604

1,115

956

422

758

809

1,536

1,395

491

551

477

1,910

613

1,199

2,289,597

391,665

1,008

1,333,074

1,627

664

1,054

690,041

766,550

151

301

675

308

413

1,109

521,237

1,176

397

2,225

216

1,609,263

862,066

3,329,876

612,605

2,662,794

584,048

1,166,937

1,885,726

1,086,603

316,817

299,644

354,768

741,834

351,017

1,341,406

1,312,248

127,504

702,404

728,988

195,308

D. Model cross-validation

150

100

50

0

● ●

●●

−50

Domain

● Bay of Bengal

Benguela

Canary

Guinea

Humbolt

Indo−Pacific

NW Pacific

NE Atlantic

NW Atlantic

Nordic Shelf Seas

California Current

0 50 100

Static Model − predicted % change in biomass density

Figure S1. Comparison of predicted percentage changes (climate relative to control) in overall fish biomass density from the static metabolic scaling model and the dynamic coupled size spectrum model. Each point represents an EEZs group by colour according the large ecosystem domains (codes in legend). Solid line is 1:1 relationship.

E. Effect of fishing on fish production and resilience to climate change across ecosystems.

B en ga l

B en gu el a

C an ar y

G ui ne a

H um bo lt

In do

−P ac ifi c

N

W

P ac

N

E

A tl

N

W

A tl

N or di c

S ea s

C al ifo rn ia a) climate, no fishing climate, low fishing climate, high fishing b)

Figure S2. Climate-projected changes in (a) large fish production and (b) Coefficients of

Variation (CVs) of large fish biomass density time series. Changes are relative to the unexploited control scenario when fishing mortality rates are = 0 (dark grey, climate only),

0.2 (light grey, low fishing) and 0.8 yr -1 (white, high fishing) for all economic zones grouped by their 11 regional ecosystems domains.

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