Cladophora and the Beach: Implications for Public Health

Colleen McDermott, D.V.M., Ph.D.

Department of Biology and MicrobiologyUniversity of Wisconsin - Oshkosh

Oshkosh, WI 54901Phone - (920) 424-1102

Fax - (920) 424-1101E-mail –mcdermot@uwosh.edu

Implications for Public Health?

• What effect does Cladophora have on beach health and the status of swimming at many Wisconsin beaches?

Freshwater Cladophora Ecology

• Filamentous, branched green algae• Often form large mats• Mainly grows attached to hard surfaces• Mats can break off and float distances• Highest abundance found in shallows of

highly eutrophic bodies of water• Although recent study found that

increased P & N not associated with increased Cladophora mats

Freshwater Cladophora Ecology

• Rarely found pure in natural systems Commonly found in communities with diatoms and

other green algae Mats resemble grey wool when dead or dying Odorous Harbor unwanted microorganisms

Cladophora Distribution Study

Ranked the presence of Cladophora on the beach on a scale of:

None (0)Low (1)Moderate (2)High (3)

ScaleLow

Cladophora minimally present in

patches on the beach.

ModerateCladophora noticeably present on the beach

and a nuisance.

HighCladophora covers beach

in wind rows.Slide adopted from WI DNR 2004.

Door County

•Out of 30 (3 inland and 27 LM) beaches monitored most had observable Cladophora at some point during 2004.•Used DNR criteria (none, low, medium, or high) for observable Cladophora and BEACH data collected on the same day to conduct a preliminary examination of a relationship between Cladophora and E.coli.

0.0

0.5

1.0

1.5

2.0

2.5

3.0

Anclai

m

Bailey

's Harb

or

Cresen

t

Egg H

arbor

Ellison

Bay

Ephrai

m

Fish C

reek

Jackso

n Harb

or Ridg

es

Kewau

nee C

ity Park

Lakesi

de

Murphy

Park

Newpo

rt

Nicolet

Bay

Otumba

Percy J

ohnso

n Mem

orial

Portag

e Park

Sand D

une B

each

Sister

Bay

Sturge

on B

ay R

ec. C

anal

Sunset

Whit

efish

Dunes

Log 1

0 E.c

oli M

PN/1

00m

L

0

0.5

1

1.5

2

2.5

3

Seasonal Mean (L

og10 E.coli M

PN/100m

L)

None Low Moderate High Season Mean

2004 Observations

n=2100+E.coli samples

Table 2: Extent of Cladophora accumulation at selected Door County beaches for Summer 2004.  

Beach Percentage of 2004 sampling affected by moderate to high Cladophora accumulations

Murphy Park 76%

Newport Bay 78%

Nicolet Bay 43%

Otumba Park 14%

Portage Park 28%

White Fish Dunes 53%

 

The Issue

• Recent research indicates: Cladophora extracts may be able to sustain E.coli

and other ‘indicator organism’ growth in recreational water.

Mats of Cladophora harbor very high levels of E.coli• Cladophora are present at many WI beach

sites.• Many questions to be asked and answered for

beach managers…….

Growth of E. coli in Cladophora leachate

Byappanahalli et al. 2003

Bacteria found in Cladophora mats in southern Lake Michigan

From Whitman et al., 2003

E. coli as an Indicator Organisms

• Intended to indicate recent fecal contamination in natural waters

• Indicator organisms can enter water from several sources (human, cattle, birds, domestic pets) and the source can tell you something about the risk to human health.

• Commensal organisms of intestines of warm-blooded animals.

• Most are not pathogenic

Host Environment — Primary Habitat

• Host provides: Warm, stable

temperature High nutrient

concentration Doubling time = 12-48

hours

Outside the Host — Secondary Habitat

• A battle for survival

• Low rate of survival

• Low probability of colonizing a new host

MAMMALIAN HOST

EXTERNAL ENVIRONMENT

Sunlight Low nutrients

PredationVariable temperature, pH and moisture

Adapted from Winfield and Groisman. 2003.

E. coli as an Indicator Organism

• It is intended to indicate recent fecal contamination in natural waters

• Chosen because: Found in feces in high numbers E. coli generally will survive longer in the environment than pathogens But-should not survive for extended periods More easily detected than pathogens

Warns us of the potential of GI tract pathogen presence

Salmonella

• Hearty as far as pathogens go.

• Relatively difficult to find in the environment.

• Many sources including avian and human.

• Require greater nutrients than E.coli.

Shigella

• Does not survive very long…less than Salmonella or E.coli

• Higher requirement for nutrients

• Primarily from human sources

Campylobacter sp.

• Survival characteristics not well studied. (Nov. 2004 AEM study)

• From avian, bovine, and human (sometimes) sources

• Ubiquitous in some areas

Norovirus

• Survival is very limited once outside the primary host.

• Implicated in several outbreaks.

• Human or bovine.

Potential Cladophora help to E.coli Survival

• Block UV light

• Increased nutrients

• Moisture retention

• More stable microbial community

• Changes the minimum at each site to favor growth and survival!

MAMMALIAN HOST

EXTERNAL ENVIRONMENT

Sunlight Low nutrients

PredationVariable temperature, pH and moisture

Adapted from Winfield and Groisman. 2003.

0.0

0.5

1.0

1.5

2.0

2.5

3.0

Anclai

m

Bailey

's Harb

or

Cresen

t

Egg H

arbor

Ellison

Bay

Ephrai

m

Fish C

reek

Jackso

n Harb

or Ridg

es

Kewau

nee C

ity Park

Lakesi

de

Murphy

Park

Newpo

rt

Nicolet

Bay

Otumba

Percy J

ohnso

n Mem

orial

Portag

e Park

Sand D

une B

each

Sister

Bay

Sturge

on B

ay R

ec. C

anal

Sunset

Whit

efish

Dunes

Log 1

0 E.c

oli M

PN/1

00m

L

0

0.5

1

1.5

2

2.5

3

Seasonal Mean (L

og10 E.coli M

PN/100m

L)

None Low Moderate High Season Mean

2004 Observations

n=2100+E.coli samples

In the ‘Mats’E. coli

(CFU/g DW)Enterococci (CFU/g DW)

Murphy (Floating) 22,515Murphy (on shore) 17,670Whitefish Dunes (Floating) 89Whitefish Dunes (on shore) 39,501 1411Lakeshore (Floating) 470Anclam South (on shore) 110Sister Bay (Floating) 10,874Baileys Harbor (on shore) 1,729 196Sunset (Floating) 1,254

Data Courtesy of: Richard Whitman, USGS

Laboratory Studies

2005 Lab Microcosm Study•Uses lake water and Cladophora from local lake •Looks at specific influence on E.coli and pathogens in a controlled setting.•Will assist in moving to field studies.

Grow Light ( 24” 20W)

Open Container w/H2O, rock, & Cladophora

Pathogens in Cladophora

• Spike Cladopha mats with:• Spike lake water with:

Salmonella Shigella Plesiomonas E. coli

• Count organism numbers over time• Replication? Survival? Death?

Salmonella survival in Cladophora mats

CFU vs. Time

1.E+00

1.E+01

1.E+02

1.E+03

1.E+04

1.E+05

1.E+06

1.E+07

1.E+08

0 24 48 72 96

Time in Hours

CFU

/mL

Control

w/ Cladophora

Field Work for 2005•Use Ozaukee, Kewaunee, and Door County beaches as a study site.•Look at spatial and temporal effects of Cladophora mats on E.coli over the summer and specific 24 hour periods.•Evaluate the genetic diversity of the E.coli isolates recovered to determine if they are transient or stable (or replicating) during the swimming season.•Evaluate any pathogens associated with the mats and at the beaches at large.•Evaluate nutrient levels and effects.

Future Work• Submitted WI Sea Grant to study Cladophora 2006-2009• Effects of Cladophora mats on beach closures

Spatial effects Replication of E. coli in mats Pathogens in mats

• Study sites Door County and Racine, WI• Collaboration between

UW-Oshkosh University of Minnesota USGS City of Racine Health Department Door County Soil & Water Department

Implications….

•Cladophora mats could allow for replication of indicator organism, E. coli, without concurrent replication of pathogens

Premature, inappropriate beach closures?Is E. coli a suitable indicator?

•Cladophora mats could allow for replication of pathogensPublic health concernManagement issues

Acknowledgements•UW-Oshkosh “Beach Group”•Door County Soil and Water Conservation Department •Door County Health Department•Ozaukee County Health Department•Vilas County Soil and Water Conservation Department•Vilas County Health Department•WI DNR•WI Bureau of Communicable Disease•USGS

Thank You!

Door County SWCD

Preliminary Data

12-7-04

Cladophora

0.0

0.5

1.0

1.5

2.0

2.5

3.0

Anclai

m

Bailey

's Harb

or

Cresen

t

Egg H

arbor

Ellison

Bay

Ephrai

m

Fish C

reek

Jackso

n Harb

or Ridg

es

Kewau

nee C

ity Park

Lakesi

de

Murphy

Park

Newpo

rt

Nicolet

Bay

Otumba

Percy J

ohnso

n Mem

orial

Portag

e Park

Sand D

une B

each

Sister

Bay

Sturge

on B

ay R

ec. C

anal

Sunset

Whit

efish

Dunes

Log 1

0 E.c

oli M

PN/1

00m

L

0

0.5

1

1.5

2

2.5

3

Seasonal Mean (L

og10 E.coli M

PN/100m

L)

None Low Moderate High Season Mean

2004 Observations

n=2100+E.coli samples

Pathogens

Table1: Pathogens detected from five selected beaches in Door County during Summer 2004. Beaches tested were Ephraim, Fish Creek, Otumba Park, Sister Bay, and Whitefish Dunes. 4 -liter water samples were taken on Tuesdays from June to September (14 weeks) at the standard monitoring site at each beach. ND= not detected from any sample for the entire summer. TNTC= too numerous to count.

Beach Salmonella Shigella Campylobacter E. coli Ephraim ND ND ND Fish Creek ND ND ND Otumba Park

6/10/04 ND ND Low 6/17/04 ND ND Moderate 365.4/100ml 6/24/04 ND ND Moderate 13.4/100ml

7/8/04 ND ND TNTC 79.6/100ml 7/15/04 ND ND TNTC 27.1/100 ml 7/22/04 ND ND TNTC 406.7/100 l 7/29/04 ND ND TNTC 52.1/100 ml 8/11/04 ND ND TNTC 88.4/100 ml 8/26/04 ND ND TNTC 35.5/100 ml

Sister Bay ND ND ND Whitefish Dunes

ND ND ND

Post Rainfall

Otumba Post Rainfall

0

250

500

750

1000

1250

1500

1750

2000

2250

2500

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24Hours After 0.25" of Rainfall

E.co

li M

PN/1

00m

L

18.4

Post Rainfall - Whitefish Dunes

0

250

500

750

1000

1250

1500

1750

2000

2250

2500

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24Hours after 0.25" Rain

E.c

oli M

PN/1

00m

L

5/21/04

Post Rainfall - Lakeside

0

250

500

750

1000

1250

1500

1750

2000

2250

2500

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24

Hours after 0.25" Rain

E.co

li M

PN/1

00m

L

5/21/048/9/04

Post Rainfall - Sister Bay

0

250

500

750

1000

1250

1500

1750

2000

2250

2500

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24

Hours after 0.25" Rain

E.co

li M

PN/1

00m

L

6/22/04

Post Rainfall - Ephraim

0

250

500

750

1000

1250

1500

1750

2000

2250

2500

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24

Hours after 0.25" Rain

E.co

li M

PN/1

00m

L

6/22/048/19/04

Post Rainfall - Murphy

0

250

500

750

1000

1250

1500

1750

2000

2250

2500

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24

Hours after 0.25" Rain

E.co

li M

PN/1

00m

L

6/28/04

Post Rainfall - Egg Harbor

0

250

500

750

1000

1250

1500

1750

2000

2250

2500

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24

Hours after 0.25" Rain

E.co

li M

PN/1

00m

L

6/28/04

Post Rainfall - Fish Creek

0

250

500

750

1000

1250

1500

1750

2000

2250

2500

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24

Hours after 0.25" Rain

E.co

li M

PN/1

00m

L

8/19/04

Post Rainfall - Otumba

0

250

500

750

1000

1250

1500

1750

2000

2250

2500

Hours after 0.25" Rain

E.co

li M

PN/1

00m

L

6/13/04 6/18/04 7/5/04 7/7/04 7/22/04 8/25/04

Post Rainfall - Sunset

0

250

500

750

1000

1250

1500

1750

2000

2250

2500

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24

Hours after 0.25" Rain

E.co

li M

PN/1

00m

L

6/13/04 6/18/04 7/5/04 7/7/04 7/22/04 8/25/04

Spatial Sampling

Depth Sampling of E.coli - Door County, WI

0

50

100

150

200

250

300

350

400

450

500

12" Average 24" Average 48" Average

Depth Sampled

E.c

oli M

PN/1

00m

L

EphraimFish CreekOtumbaSister BayWhitefish Dunes

n=102

Depth Sampling of E.coli - Door County, WI

0

50

100

150

200

250

300

350

400

450

500

Ephraim Fish Creek Otumba Sister Bay Whitefish Dunes

Location Sampled

E.c

oli M

PN/1

00m

L

12" Average24" Average48" Average

n=102

Ephraim Depth Sampling

109.3

274.4

81.8

158.8

29.6 9.3

215.4

112.7148.3

32.9 24.3 31.6 8.4 8.9 7.90

100

200

300

400

500

600

700

Outfall

1

Outfall

2

Outfall

3

12" A

verag

e

24" A

verag

e

48" A

verag

e12

L12

"M12

" R24

" L24

" M 24" R

48" L

48" C

48" R

E.c

oli M

PN/1

00m

L

n=34

Possible Beach Status Change8-5-04

Fish Creek Depth Sampling

267.5

1112.4

78.0

387.6

123.955.6

351.8404.4 410.6

100.7 105.9165.0

58.0 54.8 54.00

200

400

600

800

1000

1200

Outfall

1

Outfall

2

Outfall

3

12" A

verag

e

24" A

verag

e

48" A

verag

e12

L12

"M12

" R24

" L24

" M 24" R

48" L

48" C

48" R

E.c

oli M

PN/1

00m

L

n=34

Possible Beach Status Change5-26-047-2-047-7-04

7-21-048-5-04

8-13-04

Otumba Depth Sampling

413.0

604.7

261.3

134.2

60.5

359.1

178.4246.3

82.5142.3

177.8

40.0 66.2 75.3

0

100

200

300

400

500

600

700

Outfall

1

Outfall

2

Outfall

3

12" A

verag

e

24" A

verag

e

48" A

verag

e12

L12

"M12

" R24

" L24

" M 24" R

48" L

48" C

48" R

E.c

oli M

PN/1

00m

L

n=34

Possible Beach Status Change5-25-047-7-04

7-15-047-21-047-22-047-23-048-5-04

Sister Bay Depth Sampling

113.9 132.6

40.6 66.5 40.0 36.5 57.9107.9

33.7 39.3 55.0 27.4 39.6 44.7 24.80

100

200

300

400

500

600

700

Outfall

1

Outfall

2

Outfall

3

12" A

verag

e

24" A

verag

e

48" A

verag

e12

L12

"M12

" R24

" L24

" M 24" R

48" L

48" C

48" R

E.c

oli M

PN/1

00m

L

n=34

Possible Beach Status Change7-15-048-5-04

Whitefish Dunes Depth Sampling

51.6 59.0112.3

54.6 36.4

158.5122.6

57.1 54.588.4

21.061.5 36.4 12.6

0

100

200

300

400

500

600

700

Outfall

1

Outfall

2

Outfall

3

12" A

verag

e

24" A

verag

e

48" A

verag

e12

L12

"M12

" R24

" L24

" M 24" R

48" L

48" C

48" R

E.c

oli M

PN/1

00m

L

n=34

Possible Beach Status Change7-22-04

215.432.9

8.4

274.4

109.3

81.8

148.324.37.9

112.7

24.3

8.9

Outfalls48”24”12”

Antibiotic Resistance

Antibiotic Resistance Profiles

0.0

10.0

20.0

30.0

40.0

50.0

60.0

70.0

80.0

90.0

100.0

Ampic

illin

Augm

entin

Ceph

alothi

n

Ciprofl

axacin

Erythr

omyci

n

Gentam

ycin

Kana

mycin

Nalidixic

Acid

Novobio

cin

Polym

ixin B

Strep

tomyci

n

Sulfis

oxazo

le

Tetrac

ycline

Trimeth

oprim

Tobram

ycin

Vancom

ycin

% o

f Iso

late

s Re

sist

ant

EphraimFish CreekOtumbaSister BayWhitefish DunesHumanAvian

Antibiotic Resistance Profiles - Ephraim

0

10

20

30

40

50

60

70

80

90

100

Ampicillin

Augmen

tin

Cepha

lothin

Ciprofla

xacin

Erythr

omyc

in

Gentam

ycin

Kana

mycin

Nalidixi

c Acid

Novob

iocin

Polym

ixin B

Strep

tomyc

in

Sulfis

oxaz

ole

Tetracy

cline

Trimeth

oprim

Tobram

ycin

Vanc

omyc

in

% o

f Is

olat

es R

esis

tant

EphraimHumanAvian

N=118

Antibiotic Resistance Profiles - Fish Creek

0

10

20

30

40

50

60

70

80

90

100

Ampicillin

Augmen

tin

Cepha

lothin

Ciprofl

axac

in

Erythr

omyc

in

Gentam

ycin

Kana

mycin

Nalidixi

c Acid

Novob

iocin

Polym

ixin B

Strep

tomyc

in

Sulfis

oxaz

ole

Tetracy

cline

Trimetho

prim

Tobramyc

in

Vanc

omyc

in

% o

f Is

olat

es R

esis

tant

Fish CreekHumanAvian

N=156

Antibiotic Resistance Profiles - Otumba

0

10

20

30

40

50

60

70

80

90

100

Ampic

illin

Augm

entin

Cepha

lothin

Ciprofl

axacin

Erythrom

ycin

Gentam

ycin

Kanam

ycin

Nalidixic

Acid

Novobio

cin

Polym

ixin B

Strep

tomyci

n

Sulfis

oxazo

le

Tetrac

ycline

Trimeth

oprim

Tobram

ycin

Vancom

ycin

% o

f Is

olat

es R

esis

tant

OtumbaHumanAvian

N=128

Antibiotic Resistance Profiles - Sister Bay

0

10

20

30

40

50

60

70

80

90

100

Ampicillin

Augmen

tin

Cepha

lothin

Ciprofl

axac

in

Erythr

omyci

n

Gentam

ycin

Kana

mycin

Nalidix

ic Acid

Novob

iocin

Polym

ixin B

Strep

tomyci

n

Sulfis

oxazol

e

Tetrac

ycline

Trimeth

oprim

Tobram

ycin

Vanc

omyci

n

% o

f Iso

late

s Re

sist

ant

Sister BayHumanAvian

N=90

Antibiotic Resistance Profiles - Whitefish Dunes

0

10

20

30

40

50

60

70

80

90

100

Ampicillin

Augmen

tin

Cepha

lothin

Ciprofl

axac

in

Erythr

omyci

n

Gentam

ycin

Kana

mycin

Nalidix

ic Acid

Novob

iocin

Polym

ixin B

Strep

tomyci

n

Sulfis

oxazol

e

Tetrac

ycline

Trimeth

oprim

Tobram

ycin

Vanco

mycin

% o

f Is

olat

es R

esis

tant

Whitefish DunesHumanAvian

N=174

Genetic Testing

Lets look at Cladophora

• O.K……So now we know what an ‘indicator organism’ is and what they are supposed to represent, let us back-up and look at this Cladophora issue again……

E. coli cells in lake water mesocosms

(a) E. coli cells at day 0

(b) E. coli cells at day 4 on particles without medium

(c) E. coli cells at day 4 on particles with medium

Adapted from Brettar and Höfle. 1992.

Door and Kewaunee Counties

•High levels of E.coli recovered from the algal mats.•Correlations found at 4 locations.•Relatively high amount of observable algal growth at some locations.•Very dependent on wind conditions.•From a historical perspective more observable algae in recent years.

Vilas, Onieda, and Lake Superior Counties

•1300+ lakes in Vilas County alone•Low amount of observable algae growth•Out of 45 (18 inland and 27 LS) beaches monitored none had a chronic observable issue with Cladophora (no microystin associated)•Only one occurrence in LS and lasted for 2 days with E.coli < 10 MPN/100mL•Less of a problem here that some other locations in WI.

Vilas, Onieda, and Lake Superior Counties

•1300+ lakes in Vilas County alone•Low amount of observable algae growth•Out of 45 (18 inland and 27 LS) beaches monitored none had a chronic observable issue with Cladophora (no microystin associated)•Only one occurrence in LS and lasted for 2 days with E.coli < 10 MPN/100mL•Less of a problem here that some other locations in WI.