Climate Change Impacts on Great Lakes Fisheschangingclimate.osu.edu/webinars/ppt/stu-ludsin.pdf ·...

Climate Change Impacts onGreat Lakes Fishes

Stuart A. Ludsin

[email protected] Climate Webinar Series

The Ohio State University19 April 2011

• Great Lakes Fish Community

• A Changing Climate

• Impacts on Fishes: The Expected

• Impacts on Fishes: Ecological Surprises

• Take Home Messages

Today’s Presentation

• Diverse fish community− ~169 species− >25 exotics

• Cultural & ecological import

• Economic import– Recreational fishing– Commercial fisheries

Great Lakes Fish Community

Great Lakes Recreational Fisheries• >1.75 million anglers annually• >22 million angler days annually• $1.75 billion

YP

Walleye

Chinook Lake trout

Great Lakes Commercial Fisheries

WI

MI

OHPA

NY

INIL

ON

Species fishedMax. harvest (millions of pounds)

16

24

30

25

4.5

59.6

24.3

75.1

6.2

25

Herring

Whitefish

YP

Walleye

• Fish production depends heavily on availability of quality habitat

Pro

duct

ion

Quality habitat

• Many factors affect habitat quality & quantity− Spawning habitat− Water clarity− Prey (food)− Dissolved oxygen− Temperature

• Each species has a unique set of habitat requirements that promote maximal growth, survival, & production

• Fish distribution & abundance vary as a function of habitat– Within an ecosystem (lake)– Across ecosystems (lakes)


35

30

25

20

15

10

5

0

Pre

ferre

d te

mpe

ratu

re (º

C)

Habitat preferenceDeep/offshore Shallow/nearshore

Laketrout

Lakeherring

RainbowsmeltChinook

salmon

Burbot

Cohosalmon

WhitefishAlewife

Yellowperch

Walleye

Emeraldshiner Smallmouth

bass

Carp

Whiteperch

Gar

Bluegill

After Fig. 23, Kling et al (2003)

Whitecrappie

NorthernpikeRock

bass

Freshwaterdrum White

bassChannelcatfish

Rainbowtrout

Cold

Cool

Warm



• A Climate Changing





1950

1960

1970

1980

1990

2000

2010#

Day

s <

0o C (A

ir)

90

100

110

120

130

140

150

160

170Toledo, OH1956-2007

p<0.0001R2=0.42

Climate Change Projections: Temperature

Farmer & Ludsin, unpublished data

A Changing Climate• Lake Superior temperature increase

– Water has warmed 2-fold faster than air

Source: J. Austin, U of Minnesota, DuluthAustin and Coleman (2007)

1980 1985 1990 1995 2000 2005

1816141210

86

Air (0.06°C/yr)Water (0.12°C/yr)

Tem

pera

ture

(°C

)

• Significant increase in precipitation– Erie, Michigan, Ontario, and Huron

Climate Change Projections: Precipitation

1930 1950 1970 1990

1200

900

600

Pre

cipi

tatio

n(m

m/y

ear)

Year

Lake Ontario

McBean and Motiee (2008)

• 7-day storm events– Increased frequency

(1931 – 1996)

Climate Change Projections: Precipitation

Kunkel et al (1999)

• Shift in seasons– Longer growing season (earlier spring, later fall)– Shorter winter (by 33-88 days)

1900 1950 2000 2050 2100

220

180

140Gro

win

g se

ason

(day

s)

Year

Kling et al. (2003)

High emissions scenarioLow emissions scenario

• Higher temperatures– Summer increase: 3 – 11ºC– Winter increase: 3 – 7ºC

A Changing Climate

• Shift in seasonal rainfall– More rain in winter & spring– Less rain during the summer & fall

4

3

2

Ave.

pre

cipi

tatio

n(m

m/d

ay)

Kling et al. (2003)

High emissionsLow emissions

AJ F J JM AJ OS DN

5

• Increased frequency of storm events– Doubling of 24-hour & 7-day storms

A Changing Climate

Current

By 2030(summer)

By 2095(summer)

By 2095(winter)

A Changing Climate

Impacts on Fishes: The ExpectedAir

TemperatureSpring

Storms & Rain

Spring Nutrient &Sediment Inputs

Spring RiverDischarge

SpringRunoff

Oxygen Availability( “Dead Zones”)

WinterIce Cover

WaterTemperature

ThermalStratification

WaterLevel

Fish Growth, Survival& Production

PlanktonProduction

WaterClarity

AirTemperature

WaterTemperature


Impacts on Fishes: The Expected• Modeling to date is limited

– Direct effects of temperature

Impacts of Fishes: The Expected• Water temperature warming

– ↑ warm- and cool-water fishes– ↓ coldwater fishes

Stefan et al (1995)

100

75

50

0

-50

-75

-100

warm-H2O cool-H2O cold-H2O

Lake trout

YellowperchBluegill

% c

hang

e in

ther

mal

hab

itat

Unproductive lakes

Productive lakes

• Shifts in current species range – Northern expansion of range: warm & cool-water fishes

• Yellow perch, smallmouth bass, walleye, northern pike

Impacts on Fishes: The Expected


• Yellow perch, smallmouth bass, walleye, carp, northern pike

– Southern retraction of range: cold-water fishes• Lake trout, burbot, lake whitefish, walleye, northern pike



• Yellow perch, smallmouth bass, walleye, northern pike

– Southern retraction of range: cold-water fishes• Lake trout, burbot, lake whitefish, walleye, northern pike

• Shifts in community composition– Expansion of invasive species

• White perch, striped bass, “native” smallmouth bass

• Altered food-web interactions• Competitive & predatory interactions with new invaders

• Winners & losers will emerge


AirTemperature

WaterTemperature


Impacts on Fishes: Ecological Surprises

• Modeling has not considered most indirect effects

• Potential interactions with other human stressors have not been considered

• Modeling to date is limited– Direct effects of temperature

AirTemperature

SpringStorms & Rain



SpringRunoff


WinterIce Cover

WaterTemperature


WaterLevel


PlanktonProduction

WaterClarity


Pre

ferre

d te

mpe

ratu

re (º

C)

Habitat preferenceDeep/offshore Shallow/nearshore

Yellowperch

Cold

Cool

WarmYellow Perch

(©Shedd Aquarium)

Impacts on Fishes: Ecological Surprises35

30

25

20

15

10

5

0

West

Year1960 1970 1980 1990 2000

Age

-2 y

ello

w p

erch

abu

ndan

ce(m

illio

ns)

0

25

50

75

100

125

150

175?


Data Source: Lake Erie Committee

WaterTemperature


+

AirTemperature


Day of Year

Wat

er c

olum

n de

pth

(m)

Lake Michigan yellow perch(Magnuson et al. 1990)

AirTemperature

SpringStorms & Rain



SpringRunoff


WinterIce Cover

WaterTemperature


WaterLevel


PlanktonProduction

WaterClarity


• Enhanced bottom hypoxia (“dead zones”)– ↑ air temperature & ↓ ice cover

• ↑ phytoplankton production• ↓ water levels• ↑ thermal stratification

-83.5 -82.5 -81.5 -80.5 -79.541.5

42

42.5

43

0

4

8

12Dissolved oxygen (mg/L)

Lake ErieSept. 2005


•  Reducedaccesstobo-ominsummer→hypoxia(lowoxygen)

Cool

Warm

Warmer

Colder Low oxygen With

Climate Warming

No Climate

Warming

wouldresultin:

↓feeding↓growth

↓condi=oninfall

Yellow perch

Benthos

Benthos

ImpactsonFishes:EcologicalSurprises

Robertsetal.(2009,inpress)Arendetal.(2011)


WaterTemperature


+-


AirTemperature

SpringStorms & Rain



SpringRunoff


WinterIce Cover

WaterTemperature


WaterLevel


PlanktonProduction

WaterClarity


% fe

mal

es th

at s

paw

ned

Chill duration (days from Oct. 30)

4

6 8

10

100

60

20

120 160 200 240

MonthM A M J J

• Ho: Warmer winters could negatively affect reproduction(impair ovary development, egg production, spawning success)

Fig. 1 from Hokanson (1977)

Treatmenttemperature


At least 165 daysbelow 6°C for

100% spawning

Western

100

200

0Age

-0 Y

P C

PU

E

0

0.0 0.5 1.0 1.5 2.0 2.5 3.0

Winter water temperature (°C)

x = 0.27p = 0.03


• Ho: Warmer winters could negatively affect reproductive(ovary development, fecundity, spawning or egg/larval survival)

1969-2006

T. Farmer, OSU, unpublished


WaterTemperature


+-

WinterIce Cover

-


AirTemperature

SpringStorms & Rain



SpringRunoff


WinterIce Cover

WaterTemperature


WaterLevel


PlanktonProduction

WaterClarity


SpringStorms & Rain



SpringRunoff


PlanktonProduction

WaterClarity


Ho: Increased precipitation-driven

runoff/discharge could benefit fisheries via inputs of nutrients and/or sediments

April-May Maumee R. discharge(m3 / sec)

100 300 500

Age

-2 y

ello

w p

erch

(mill

ions

)

1

10

100

'87

'88

'89'90

'91

'92

'93'94'95

'96

'97

'98 '99

'00

'01'03

'04

'05

'06

'02

1987-2006

(r = 0.84)

Ho: Increased precipitation-driven

runoff/discharge could benefit fisheries via inputs of nutrients and/or sediments


S. Ludsin, unpublished data

Log10(April-May Maumee River discharge)(m3 / sec)

100 300 500

Log 10

(age

-2 y

ello

w p

erch

)(m

illio

ns)

1

10

100

1000

'58

'59

'60 '61

'62

'63

'64

'65

'66

'67'68'69

'70'71

'72'73

'74'75

'76

'77

'78'79

'80

'81

'82

'83

'84

'85

'86

100 300 500

'87

'88

'89'90

'91

'92

'93'94'95

'96

'97

'98'99

'00

'01'03

'04

'05

'06

'02

1958-1986 1987-2006

(r = 0.84)

Relationship holds only in new regime

Impacts on Fishes: Ecological SurprisesHo: Precipitation-driven runoff/discharge could benefit fisheries via inputs of nutrients and/or sediments

S. Ludsin, unpublished data



WaterTemperature


PlanktonProduction

WaterClarity

+- +

WinterIce Cover

-


Take Home Messages• Climate change will affect Great Lakes fishes

– Alter distribution of abundance, fish community composition– Some fisheries will benefit, others will not

• Ability to forecast effects is still in its infancy– Most studies have focused on direct temperature effects– However, numerous other direct/indirect effects likely (via river

discharge, hypoxia, warm winters)

• Need more mechanistic research & modeling– Synergies (Ho: hypoxia + warm winters = ↓ reproduction)– Interactions (Ho: ↑ precipitation/runoff is both good & bad)– Climate change effects are context- (regime) dependent

Thanks for your attention!

Climate Change Impacts on Great Lakes Fisheschangingclimate.osu.edu/webinars/ppt/stu-ludsin.pdf ·...

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