Effects of Multiple Stressors on Aquatic Communities in the Prairie

Pothole RegionPatrick K. Schoff and Lucinda B. JohnsonNatural Resources Research InstituteUniversity of Minnesota Duluth

Glenn GuntenspergenUS Geological SurveyPatuxent River, Maryland

Carter JohnsonSouth Dakota State UniversityBrookings, South Dakota

UVexoticspesticides

emerging diseasesnew parasites

development /habitat fragmentation

acidification

pharmaceuticalseutrophication

desiccation

novel predators

temperature

Amphibian Stressors

Indicators of Ecosystems in Jeopardy

population reductions

Emerging diseases of wildlife

Human epidemiologycancersasthmaheart disease

Wildlifeepidemiology

intersexparasitescancersmalformation

exotic / invasive species

local extinctions

species extinction

Degraded Environment

CWDBSE / vJCDAIDSSARSEbolaAvian InfluenzaWest Nile Virus

Emerging diseases in humans

Prairie Pothole Region

Critical freshwater resource• habitat

- breeding waterfowl- migration stopover- macroinvertebrates- amphibians

• flood water storage

Anthropogenic Stressors Affecting the Prairie Pothole Region

Climate change• increased temperature• decreased moisture

UV radiation• reduced DOC inputs (?)

Habitat restructuring/destruction• ~50% of wetlands drained in previous century• remaining wetlands embedded in agricultural matrix

Agricultural practices• excess nutrients• pesticides

Stressor Effects on Amphibians

GlobalClimateChange

AgriculturalPractices

habitat restructuringpesticidesnutrients

accelerated developmentimmune dysfunctionspecies diversity (?)

physiological stressimmune dysfunctiondisease susceptibilitydevelopmental anomalies

temperature precipitation UV-B radiation

Stressors Biological Effects

Objectives

1. Quantify relationships among differing land use, amphibian community structure and composition in the prairie pothole region.

• hydroperiod (semi-permanent v. seasonal) • crop v. grassland

2. Quantify relationships among physical and chemical wetland attributes on amphibian organismal and community responses.

• hydroperiod• thermal regime• pH

Objectives, cont.

3. Quantify the effects of multiple stressors on health and organismal responses of Rana pipiens.

• shortened hydroperiod• increased UV-B radiation

4. Predict potential effects of multiple stressors on prairie pothole wetlands and associated amphibian communities.

Stressor Effects on Amphibians

Accelerated Hydroperiod (warmer, less water)• faster development• smaller metamorphs • reduced fat stores = reduced fitness

Increased UV-B radiation (ozone depletion, +/- reduced DOC)• edema• malformations• impaired immune function • mutagenic effects

Atrazine (most commonly used herbicide)• endocrine disruption (?)

- gonadal dysmorphogenesis (♂♀) - laryngeal muscle reduction (♂)

• developmental delays

Approach

Landscape scale (Extensive study)– relationships among amphibian community structure, land use, and wetland hydrologic regime

Wetland scale (Intensive study)– relationships among individual wetlands (hydroperiod, physico-chemical), land uses (e.g. pesticides), UV-B, amphibian abundance, community structure, and health

Mesocosm scale– effects of multiple stressors (hydroperiod and pesticide)

on Rana pipiens development and health

project organizationL e v e l IM e s o c o s m• H y d r o p e r i o d• A t r a z i n e• H y d r o p e r i o d x A t r a z i n e

G o a l : D e t e r m i n e s i z e a n d d i r e c t i o n o f e f f e c t s o n a m p h i b i a n h e a l t h .

L e v e l I IC o t e a u R e g i o n• H y d r o p e r i o d

• T e m p o r a r y• S e a s o n a l• S e m i - p e r m a n e n t

• L a n d U s e• R o w c r o p• G r a z i n g

G o a l : A s s e s s e f f e c t s o n a m p h i b i a n h e a l t h , a b u n d a n c e , a n d c o m m u n i t y s t r u c t u r e i n t h e c o n t e x t o f v a r y i n g l o c a l a n d l a n d s c a p e f e a t u r e s .

L e v e l I I IP r a i r i e P o t h o l e R e g i o n• E c o r e g i o n ( 5 )• L a n d u s e ( 2 )• H y d r o p e r i o d ( 3 )

G o a l : A s s e s s t h e e x t e n t t o w h i c h a m p h i b i a n c o m m u n i t y r e s p o n s e s t o h y d r o p e r i o d a n d l a n d u s e c a n b e e x t r a p o l a t e d a c r o s s t h e P P R .

W E T S C A P E : P r e d i c t s h y d r o l o g y a n d v e g e t a t i o n u n d e r d i f f e r e n t c l i m a t e ( a n d u l t i m a t e l y , l a n d u s e ) r e g i m e s .

G o a l : P r e d i c t a m p h i b i a n o r g a n i s m a la n d c o m m u n i t y r e s p o n s e s u n d e r

d i f f e r e n t c l i m a t e a n d l a n d u s e s c e n a r i o s .

F i g u r e 2 . P r o j e c t o r g a n i z a t i o n .

T h e o r e t i c a l m o d e l o f a m p h i b i a n a b u n d a n c e & c o m m u n i t y s t r u c t u r e

Multiple Stressors Study

Extensive study:• Prairie Pothole Region • goal = 120 wetlands (2004 = 63 wetlands)• 2004, 2005

Intensive study:• Prairie Coteau ecoregion• goal = 60 wetlands (2003 = 27 wetlands)• a portion under study in an ongoing hydrological research program• 2003 - 2005

Mesocosm study:• 2003 pilot study• 2004 – 2005 full-scale

2 hydroperiod categories:seasonalsemi-permanent

2 use classes:row cropgrazing/pasture

IntensiveStudy Area

Prairie Pothole Region

Intensive Study (2003 – 2005)

Wetland morphology

size; configuration; depth profile; hydrologic regime

Habitat vegetative cover maps; land use; distance to wetlands, fields, roads & structures

Water column continuous temp; sp. conductance; pH; depth (weekly); spectral scans; UV attenuation; pesticide analysis (atrazine); chlorophyll-A

Microclimate temperature; humidity; precipitation; cloud cover; wind speed

Amphibian community

calling surveys; VES surveys & trapping for amphibian larvae (biweekly)

Category Parameter

5

10

15

20

25

30

35

Semi-permanent-cropSemi-permanent-grasslandSemi-permanent-cropSemi-permanent-grassland

WetlandTypes

Tem

pera

ture

( C

)

Wetland Temperatures - 2003

Water Loss in Wetlands - 2003

11 May25 May 8 J une 22 J une 5 J uly 19 J uly 2 Aug0.0

0.2

0.4

0.6

0.8

1.0

Week in 2003

Pro

port

ion

of s

ites

con

tain

ing

wat

er

0 10 20 30 40 50 60 700

20

40

60

80

100

120

140

160

Water depth (cm)

Met

amor

phs

colle

cted

Metamorphs Captured – Week 10

Wetland pH - 2003

5.5

6.0

6.5

7.0

7.5

8.0

8.5

9.0

9.5

Semi-Permanent-cropSemi-Permanent-grassland Seasonal-crop Seasonal-grassland

WetlandTypes

pH

Wetland Conductivity - 2003

0

500

1000

1500

2000

2500

Semi-Permanent - crop Semi-Permanent - grasslandSeasonal - cropSeasonal - grassland

Con

duct

ivity

(S

)

WetlandTypes

Malformation Prevalence - 2003

0

2

4

6

8

10

Semi-permanent cropSemi-permanent grasslandSeasonal cropSeasonal grassland

WetlandTypes

% M

alfo

rme

d

Malformations - 2003

• metamorphs 1475• malformed individuals 45• prevalence range 0 – 7.8%• overall prevalence 3.1% (Midwest study = 2.0%)

Malformation prevalence:

• 27 wetlands• 7 dry• 8 with < 10 metamorphs captured (n = 14)• 12 with >10 metamorphs captured (n = 1475) (avg. = 123; range = 22 - 155)

Survey

Malformation Prevalence by Wetland Type

Wetland Category Wetlands Metas. Malfs. Prev. (%)

Semi-permanent crop 1 132 2 1.5

Semi-permanent grassland 8 913 25 2.4

Seasonal crop 1 153 12 7.8

Seasonal grassland 2 277 6 2.2

Total 12 1475 45 3.1%

Extensive Study Blocks (2004)

DRY

DRY

0 50 100 150 200 250 300 Miles

Extensive Study (2004 – 2005)

Wetland morphology size; configuration; depth profile; hydrologic regime

Habitat vegetative cover maps; land use; distance to wetlands, fields, roads, & structures

Water column temperature; pH; spectral scans; water color @ 440 nm

Microclimate temperature; humidity; precipitation; cloud cover; wind speed

Amphibian community

calling surveys; VES surveys & trapping for amphibian larvae

Category Parameter

Mesocosm Scale

Goal – replicate environmentally relevant multiple stressor exposure under controlled conditions:

1. accelerated hydroperiod 2. atrazine

Hydroperiod1. normal hydroperiod – drawdown tied to field conditions2. accelerated hydroperiod – drawdown at increased rate

Atrazine1. 0.1 g/L – found by Hayes and others to cause gonadal dysmophogenesis2. 20 g/L – commonly found in ground and surface water in corn-growing areas3. 200 g/L – occasionally found in surface water

Mesocosms - 2003“Pilot year” for mesocosms (late start limited options)

• survival• density• temperature• feeding• atrazine exposure tests:

1) control, no addition 2) solvent (acetone) 3) atrazine, 20 g/L 4) atrazine, 200 g/L

Results:• limited development• no metamorphs

Interpretation:• suspect water source• late collection of tadpoles• long holding time in aquarium• high temperatures in mesocosms

Mesocosms - 2004Modifications:

• lake water• addition of shade cloth• insulated tubs with straw• successful early egg mass collection• limited holding time (larvae transferred at Gosner stage 20+)

Mesocosms - 2004

Treatments (stressors):

hydrology: normal or acceleratedatrazine: 0, 0.1, 20,200 g/L

9 treatment categories:

1. normal hydrology, no additions2. accelerated hydrology, no additions3. normal hydrology, solvent control (acetone)4. normal hydrology, atrazine 0.1 g/L5. normal hydrology, atrazine 20 g/L6. normal hydrology, atrazine 200 g/L7. accelerated hydrology, atrazine 0.1 g/L8. accelerated hydrology, atrazine 20 g/L9. accelerated hydrology, atrazine 200 g/L

Modeling

• Multi-basin wetland complex model based on WETSIM (Poiani et al. 1996) • Consists of interacting submodel components: surface water, groundwater, and vegetation. • Simulates changes in water level and vegetation cover for prairie wetland complexes that include 3 hydrologic classes:

• semi-permanent,• seasonal, • temporary

• HADCM3 climate scenarios will be used to parameterize model.

W A T E R T O W N , S D

P R A I R I E C O T E A U

M U E N S T E R , S K

C A N A D I A N A S P E N F O R E S T S A N D P A R K L A N D S

M I N O T , N D

N O R T H E R N M I X E D

G R A S S L A N D S

M E D I C I N E H A T , A B

N O R T H E R N S H O R T

G R A S S L A N D S

C R O O K S T O N , M N

N O R T H E R N T A L L G R A S S L A N D S

A L G O N A , I A

C E N T R A L T A L L G R A S S L A N D S

T E M P E R A T U R E + 3 O C

P R E C I P I T A T I O N

– 2 0 %

T E M P E R A T U R E + 3 O C

P R E C I P I T A T I O N + 2 0 %

T E M P E R A T U R E + 3 O C

H I S T O R I C

W A T E R T O W N , S D

P R A I R I E C O T E A U

M U E N S T E R , S K

C A N A D I A N A S P E N F O R E S T S A N D P A R K L A N D S

M I N O T , N D

N O R T H E R N M I X E D

G R A S S L A N D S

M E D I C I N E H A T , A B

N O R T H E R N S H O R T

G R A S S L A N D S

C R O O K S T O N , M N

N O R T H E R N T A L L G R A S S L A N D S

A L G O N A , I A

C E N T R A L T A L L G R A S S L A N D S

T E M P E R A T U R E + 3 O C

P R E C I P I T A T I O N

– 2 0 %

T E M P E R A T U R E + 3 O C

P R E C I P I T A T I O N + 2 0 %

T E M P E R A T U R E + 3 O C

H I S T O R I C

W A T E R T O W N , S D

P R A I R I E C O T E A U

M U E N S T E R , S K

C A N A D I A N A S P E N F O R E S T S A N D P A R K L A N D S

M I N O T , N D

N O R T H E R N M I X E D

G R A S S L A N D S

M E D I C I N E H A T , A B

N O R T H E R N S H O R T

G R A S S L A N D S

C R O O K S T O N , M N

N O R T H E R N T A L L G R A S S L A N D S

A L G O N A , I A

C E N T R A L T A L L G R A S S L A N D S

T E M P E R A T U R E + 3 O C

P R E C I P I T A T I O N

– 2 0 %

T E M P E R A T U R E + 3 O C

P R E C I P I T A T I O N + 2 0 %

T E M P E R A T U R E + 3 O C

H I S T O R I C

W A T E R T O W N , S D

P R A I R I E C O T E A U

M U E N S T E R , S K

C A N A D I A N A S P E N F O R E S T S A N D P A R K L A N D S

M I N O T , N D

N O R T H E R N M I X E D

G R A S S L A N D S

M E D I C I N E H A T , A B

N O R T H E R N S H O R T

G R A S S L A N D S

C R O O K S T O N , M N

N O R T H E R N T A L L G R A S S L A N D S

A L G O N A , I A

C E N T R A L T A L L G R A S S L A N D S

T E M P E R A T U R E + 3 O C

P R E C I P I T A T I O N

– 2 0 %

T E M P E R A T U R E + 3 O C

P R E C I P I T A T I O N + 2 0 %

T E M P E R A T U R E + 3 O C

H I S T O R I C

Modeling Climate Change

Algona, IACentral Tall Grasslands

Crookston, MNNorthern Tall Grasslands

Minot, NDNorthern Mixed Grasslands

Watertown, SDPrairie Coteau

Historic T +3oCP +20%

T +3oC

P - 20%

T +3oC

A B

C D

Modeling Climate Change

Challenges1. Site availability and landowner cooperation.

• farmer/rancher sensitivity to researchers• lack of “crop” wetland sites

2. Who would do wetland research in a drought?

3. UV monitoring in continually windy conditions.

4. Availability of target frog (Rana pipiens) eggs for mesocosms; variability due to local weather & short-term climate conditions.

5. Mesocosms:• frog survival• metamorph development

This research has been supported by the U.S. EPA Science to Achieve Results (STAR) Multiple Stressors Initiative.

RD-83087901-0

Acknowledgments

Dr. Catherine Johnson, National Forest ServiceDr. Nels Troelstrup, South Dakota State University

Jennifer Olker MilanAngela Rohweder

Dena ShelleyKatie BrownDeborah EndrissChandler SchmutzerDenise GregorieJanna GoldrupSarah SyriaPatti Kramer