development of a predation index to assess · development of a predation index to assess. trophic...

Development of a predation index to assesstrophic stability in the Gulf of Alaska

RASMUSON FISHERIES

RESEARCH CENTER

- N. Gulf of Alaska Applied Research Award -

Cheryl Barnes, UAF

Anne Beaudreau, UAF

Martin Dorn, AFSC

Kirstin Holsman, AFSC

Franz Mueter, UAF

newbie

Predation: important source of mortality for marine fishes

• shapes size and age structures

• impacts recruitment and survival

Georges Bank BalsfjordenS. Benguela

North Sea Barents SeaE. Bering Sea

Bax 1991

mortality due to predation by other fish

> larval and early juvenile stages

pred

atio

n an

d tro

phic

stab

ility

in th

e G

ulf o

f AK

pred

atio

n an

d tro

phic

stab

ility

in th

e G

ulf o

f AK

Walleye Pollock (Gadus chalcogrammus)

Gaichas et al. 2015

5%W. Pollock

23%Pacific Halibut

33%Arrowtooth Flounder

16%Pacific Cod

6%Other Fishes 1%

Unexplained

8% Marine Mammals

1% Skates

pred

atio

n an

d tro

phic

stab

ility

in th

e G

ulf o

f AK


Gaichas et al. 2015

5%W. Pollock

23%Pacific Halibut

33%Arrowtooth Flounder

16%Pacific Cod

6%Other Fishes 1%

Unexplained

1% Skates84% mortality

due to predation by fish

8% Marine Mammals

mortality due to predation by other fishes

pred

atio

n an

d tro

phic

stab

ility

in th

e G

ulf o

f AK


0

500000

1000000

1500000

2000000

2500000

3000000

1961 1963 1965 1967 1969 1971 1973 1975 1977 1979 1981 1983 1985 1987 1989 1991 1993 1995 1997 1999 2001 2003 2005 2007 2009 2011 2013 2015 20171960 1970 19901980

1

2

3

2000

Gro

und

fish

Biom

ass (

milli

ons o

f ton

s)

Dorn et al. 2017

2010

Walleye PollockGulf of Alaska

pred

atio

n an

d tro

phic

stab

ility

in th

e G

ulf o

f AK

0

500000

1000000

1500000

2000000

2500000

3000000

1961 1963 1965 1967 1969 1971 1973 1975 1977 1979 1981 1983 1985 1987 1989 1991 1993 1995 1997 1999 2001 2003 2005 2007 2009 2011 2013 2015 20171960 1970 19901980

1

2

3

2000

Gro

und

fish

Biom

ass (

milli

ons o

f ton

s)

2010

Walleye PollockArrowtooth FlounderPacific CodPacific HalibutSablefish

Gulf of Alaska

Dorn et al. 2017; Spies et al. 2017; Barbeaux et al. 2017; Stewart and Hicks 2017; Hanselman et al. 2017

pred

atio

n an

d tro

phic

stab

ility

in th

e G

ulf o

f AK

0

500000

1000000

1500000

2000000

2500000

3000000

1961 1963 1965 1967 1969 1971 1973 1975 1977 1979 1981 1983 1985 1987 1989 1991 1993 1995 1997 1999 2001 2003 2005 2007 2009 2011 2013 2015 20171960 1970 19901980

1

2

3

2000

Gro

und

fish

Biom

ass (

milli

ons o

f ton

s)

2010


Gulf of Alaska


pred

atio

n an

d tro

phic

stab

ility

in th

e G

ulf o

f AK

Research Questions1) How does predation intensity change through time and space?

0

500000

1000000

1500000

2000000

2500000

3000000

1961 1963 1965 1967 1969 1971 1973 1975 1977 1979 1981 1983 1985 1987 1989 1991 1993 1995 1997 1999 2001 2003 2005 2007 2009 2011 2013 2015 20171960 1970 19901980

1

2

3

2000

Gro

und

fish

Biom

ass (

milli

ons o

f ton

s)

2010


Gulf of Alaska


pred

atio

n an

d tro

phic

stab

ility

in th

e G

ulf o

f AK


2) How stable is the demersal food web in the Gulf of Alaska?

pollock consumed per year and area (MT) =

pred

atio

n an

d tro

phic

stab

ility

in th

e G

ulf o

f AK

Research Question

1) How does predation intensity vary in time and space?


pred

atio

n an

d tro

phic

stab

ility

in th

e G

ulf o

f AK

Research Question


totalpredator biomass

KG


pred

atio

n an

d tro

phic

stab

ility

in th

e G

ulf o

f AK

Research Question


*relative

predator densitytotal

predator biomass

KG


pred

atio

n an

d tro

phic

stab

ility

in th

e G

ulf o

f AK

Research Question


* *relative


predator biomassmean

annual ration

KG


pred

atio

n an

d tro

phic

stab

ility

in th

e G

ulf o

f AK

Research Question


* * *proportions of

pollock consumedrelative



annual ration

KG


pred

atio

n an

d tro

phic

stab

ility

in th

e G

ulf o

f AK

Research Question


* * * *proportions of

pollock consumedages of pollock

consumedrelative



annual ration

KG


Kitchell et al. 1977Hanson et al. 1997Harvey 2009Holsman and Aydin 2015Holsman et al. 2019



consumed

Barbeaux et al. 2017Dorn et al. 2017Hanselman et al. 2017Spies et al. 2017Stewart and Hicks 2017

- Resource Ecology and Ecosystem Modeling ProgramAlaska Fisheries Science Center, NOAA

Livingston et al. 2017

- Resource Assessment and Conservation Engineering Division- Marine Ecology and Stock Assessment Program

Alaska Fisheries Science Center, NOAA

- International Pacific Halibut Commission

relativepredator density

totalpredator biomass

meanannual ration

KG

pred

atio

n an

d tro

phic

stab

ility

in th

e G

ulf o

f AK

Research Question


pred

atio

n an

d tro

phic

stab

ility

in th

e G

ulf o

f AK

Research Question





consumedrelative



annual ration

KG

Pollo

ck C

onsu

mp

tion

(mill

MT)

Arrowtooth FlounderPacific CodPacific HalibutSablefishWalleye Pollock

pred

atio

n an

d tro

phic

stab

ility

in th

e G

ulf o

f AK

74%

6%

16%

4% 1%

Pollo

ck C

onsu

mp

tion

(mill

MT)

Arrowtooth FlounderPacific CodPacific HalibutSablefishWalleye Pollock

pred

atio

n an

d tro

phic

stab

ility

in th

e G

ulf o

f AK


2) How stable is the demersal food web in the Gulf of Alaska?

the portfolio effectpr

edat

ion

and

troph

ic st

abilit

y in

the

Gul

f of A

K

synchrony

diversity ∝ stabilityWits University Coral Reef AllianceMarket Watch


edat

ion

and

troph

ic st

abilit

y in

the

Gul

f of A

K

Com

mun

ity B

iom

ass

Time

Adapted from Oken et al. 2018


edat

ion

and

troph

ic st

abilit

y in

the

Gul

f of A

K

Time


Variance

Com

mun

ity B

iom

ass


edat

ion

and

troph

ic st

abilit

y in

the

Gul

f of A

K

A

BC

Com

mun

ity B

iom

ass

Time


Variance

A

B

C


edat

ion

and

troph

ic st

abilit

y in

the

Gul

f of A

K

A

BC

community biomass

community biomass

community biomass

Time

Synchronous


Variance

Com

mun

ity B

iom

ass

species biomass


edat

ion

and

troph

ic st

abilit

y in

the

Gul

f of A

K

A

B

C

A

BC

community biomass

Time

Synchronous

Statistically Independent


Variance

Com

mun

ity B

iom

ass


edat

ion

and

troph

ic st

abilit

y in

the

Gul

f of A

K

A

B

C

A

BC

Time

Synchronous



Variance

A

BC

A

B

Com

mun

ity B

iom

ass


edat

ion

and

troph

ic st

abilit

y in

the

Gul

f of A

K

CAsynchronous

Time


Variance

A

BC

A

B

Com

mun

ity B

iom

ass


edat

ion

and

troph

ic st

abilit

y in

the

Gul

f of A

K

C

portfolioeffect

Synchronous


Asynchronous

Time


Variance

A

BC

A

B

Com

mun

ity B

iom

ass


edat

ion

and

troph

ic st

abilit

y in

the

Gul

f of A

K

C

portfolioeffect

Synchronous


Asynchronous

LESS STABLE

MORE STABLE

YouTube

pred

atio

n an

d tro

phic

stab

ility

in th

e G

ulf o

f AK

Sports Illustrated

the portfolio effect

pred

atio

n an

d tro

phic

stab

ility

in th

e G

ulf o

f AK

variance in total consumption

sum of predator-specific variancessynchrony =

portfolio effect = 1 - synchrony

Spatial Scales:Time Series: 1990 to 2015

- Basin- Pollock Stock Assessment Area- Subregion- INPFC Statistical Area

Gulf of Alaska

pred

atio

n an

d tro

phic

stab

ility

in th

e G

ulf o

f AK






Eastern

Western

Central

pred

atio

n an

d tro

phic

stab

ility

in th

e G

ulf o

f AK






1990 to 2015pr

edat

ion

and

troph

ic st

abilit

y in

the

Gul

f of A

K

Gulf of Alaska

1990 to 2015

- 0.42

pred

atio

n an

d tro

phic

stab

ility

in th

e G

ulf o

f AK

1990 to 2003 2005 to 2015

- 0.42

1990 to 2003

1990 to 2015pr

edat

ion

and

troph

ic st

abilit

y in

the

Gul

f of A

K

2005 to 2015

0.13

pred

atio

n an

d tro

phic

stab

ility

in th

e G

ulf o

f AK

1990 to 2015

Western

Central

Eastern

pred

atio

n an

d tro

phic

stab

ility

in th

e G

ulf o

f AK

1990 to 2015pr

edat

ion

and

troph

ic st

abilit

y in

the

Gul

f of A

K

1990 to 2003 2005 to 2015

N/A

- 0.30

- 0.34

1990 to 2015

1990 to 2003

- 0.17

N/A

0.31

N/A

- 0.30

- 0.34

pred

atio

n an

d tro

phic

stab

ility

in th

e G

ulf o

f AK

2005 to 2015

1990 to 2015

1990 to 2003 2005 to 2015

N/A

- 0.30

- 0.34

- 0.17

N/A

0.31

- 0.03

0.06

- 0.36

pred

atio

n an

d tro

phic

stab

ility

in th

e G

ulf o

f AK

Key Findingspr

edat

ion

and

troph

ic st

abilit

y in

the

Gul

f of A

K

• intense and highly-variable predation

• Arrowtooth Flounder = dominant predator

• synchronous consumption dynamics− increased through time

• dep. on scale/location

Ecological Inferences• trophic instability in the Gulf of Alaska• spatial heterogeneity: buffer


Potential for Top-Down Control

+

-

Key Findingspr

edat

ion

and

troph

ic st

abilit

y in

the

Gul

f of A

K

• trophic instability in the Gulf of Alaska• spatial heterogeneity: buffer

Ecological Inferences



Con

sum

ptio

n Sy

nchr

ony

+

-





Key Findingspr

edat

ion

and

troph

ic st

abilit

y in

the

Gul

f of A

K

• trophic instability in the Gulf of Alaska

• strong top-down control over pollock

- spatial heterogeneity: buffere.g., Thorson et al. 2018

Ecological Inferences



Predator Diversity

Con

sum

ptio

n Sy

nchr

ony

+

-






Applications


Applications

- temporal variation in portfolio effects

Zador and Yasumiishi 2018

GOA: Ecosystem Status Report


Applications

GOA: Ecosystem and Socioeconomic Profile (ESP)- appendix to SAFE Report

Martin DornAFSC, NOAA

- modifier for constant natural mortality

- spatially-explicit, time-varying, age-specific estimates of predation

“gross caricatures of complex natural systems” – Nicholas J. Bax 1991

scalespace

time

spatial heterogeneity

“gross caricatures of complex natural systems” – Bax 1991

Committee & Co-AuthorsAnne BeaudreauLorenzo CiannelliMartin DornKirstin HolsmanMary HunsickerFranz MueterTerry QuinnRichard Yamada

UAFCoastal Fisheries Ecology LabJordan Watson

Acknowledgments

Funding:

Data provided by:

RASMUSON FISHERIES

RESEARCH CENTER

N. Gulf of Alaska Applied Research Award (2018, 2019)

AFSC, NOAAKerim AydinSteve BarbeauxDana HanselmanGeoff LangWayne PalssonNancy RobersonMark Zimmerman

IPHCIan StewartThomas Kong

Fish ArtNick Ingram

Cheryl L. BarnesCFOS, University of Alaska Fairbanks

[email protected]://github.com/cheryl-barnes/

Gulf of Alaska Food Web

Aydin et al. 2007

Aydin et al. 2007

Top down control in the Gulf of Alaska

Arrowtooth Flounder - Spies et al. 2017Walleye Pollock - Dorn et al. 2017Pacific Halibut - Stewart and Hicks 2017 +

Pacific Cod - Barbeaux et al. 2017Sablefish - Hanselman et al. 2017

Gulf of Alaska

pred

atio

n an

d tro

phic

stab

ility

in th

e G

ulf o

f AK

Con

sum

ptio

n of

Wal

leye

Pol

lock

(mill

MT)

Wal

leye

Pol

lock

(mill

MT)

1.511.34

2.76

1.53

3.57

3.05

2.37 2.90

0.74

0.48

0.74

0.45

pred

atio

n an

d tro

phic

stab

ility

in th

e G

ulf o

f AK

1.30[- 0.30]

0.97[0.03]

1.19[- 0.19]

0.95[0.05]

1.31[- 0.31]

1.22[- 0.22]

0.88[0.12]

1.30[- 0.30]

0.64[0.36]

N/A

N/A

N/A

N/A

1990 to 2003 2005 to 2015

1990 to 2015pr

edat

ion

and

troph

ic st

abilit

y in

the

Gul

f of A

K

CtenophoraCnidariaMolluscaTeuthidaOctopodaAnnelidaCrustaceaEuphausiaceaMisc. ShrimpsMisc. CrabsEchinodermataTunicataChondrichthyesTeleosteiClupeiformesSalmoniformesOsmeriformesArgentiniformesMyctophiformesGadiformes

G. chalcogrammusG. macrocephalus

PerciformesTrachiniformesScorpaeniformesPleuronectiformesOffalOther

1+ yr, ≥ 19 cm

529 520 1283 415 951 358 189 383 602 592 728 696

Prop

ortio

n of

Pre

y C

onsu

med

(by

wei

ght)

pred

atio

n an

d tro

phic

stab

ility

in th

e G

ulf o

f AK

0+ yr, ≥ 0 cm

685 799 463 339 598 231 195 534 720 843 871 806




Prop

ortio

n of

Pre

y C

onsu

med

(by

wei

ght)

pred

atio

n an

d tro

phic

stab

ility

in th

e G

ulf o

f AK

336 341 228 104 640 160 98 455 411 410 929 660

8+ yr, ≥ 82 cm




*

Prop

ortio

n of

Pre

y C

onsu

med

(by

wei

ght)

pred

atio

n an

d tro

phic

stab

ility

in th

e G

ulf o

f AK

2+ yr, ≥ 45 cm

194 208 45 44 216 109 94 194 227 193 0 0




Prop

ortio

n of

Pre

y C

onsu

med

(by

wei

ght)

pred

atio

n an

d tro

phic

stab

ility

in th

e G

ulf o

f AK

3+ yr, ≥ 37 cm




599 583 227 246 312 375 148 402 601 569 603 602

Prop

ortio

n of

Pre

y C

onsu

med

(by

wei

ght)

pred

atio

n an

d tro

phic

stab

ility

in th

e G

ulf o

f AK

development of a predation index to assess · development of a predation index to assess. trophic...

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