Aswani K. Volety, Michael Savarese, Greg Tolley, Lesli Haynes, Amanda Booth; Coastal Watershed Institute,

Florida Gulf Coast UniversityFlorida Gulf Coast University

William Arnold; Florida Wildlife Research Institute

Patricia Goodman, Patricia Sime, Peter Doering; South Florida Water Management District

HistoricHistoric

FlowFlow

CurrentCurrent

FlowFlow

QualityQuantity

Getting The Water Right

Timing Distribution

Northern Estuaries

Applicability of the oyster indicator species

to CERP

� Oyster life cycle is typical of other estuarine species.

� Oyster reefs provide habitat, shelter, and food for over 300 species.

� Oyster reefs contribute to benthic-pelagic coupling.

Oysters are primary consumers. � Oysters are primary consumers.

� Productivity and community structure are directly linked to hydrology .

� Secondary habitat and food source for 2 and 3 carnivores.

� Oyster-reef survival, distribution, and aerial extent are key indicators (performance measures) in most RECOVER Conceptual Ecological Models and in CERP Interim Goals;

Advantages of the oyster indicator

� The indicator is feasible to implement and is scientifically defensible

� The indicator is sensitive to System Drivers (Stressors)

� The indicator is integrative� The indicator is integrative

� Goals and Performance measures are established in the RECOVER MAP for the indicator and the following metrics are being monitored

Conceptual model – Eastern oyster

Water Management

HydrodynamicsSedimentation(muck and rate)

SalinityAdult Density Temperature

Predation

DO

Larval Recruitment

Disease

Food

Reproduction

Substrate

Oyster Abundance and Health

Performance measures� Number of live oysters per square meter;

� Number of acres of oyster reefs;

� Condition index of live oysters;

Disease prevalence and intensity of Perkinsus marinus� Disease prevalence and intensity of Perkinsus marinus

in oysters;

� Larval / spat recruitment

� Reproduction.

� Growth and survival

Caloosahatchee RiverCaloosahatchee River

STUDY SITESSTUDY SITES

12

1. Piney Point2. Cattle Dock3. Bird Island

Gulf of MexicoGulf of MexicoSanibel

Island

Sanibel

Island

San Carlos

Bay

San Carlos

Bay

2

3

4

5

3. Bird Island4. Kitchel Key5. Tarpon Bay

Parameters measured� Temperature, salinity, D. O.

� Flow (CFS; SFWMD)

� Condition Index

Perkinsus marinus intensity and prevalence� Perkinsus marinus intensity and prevalence

� Gonadal Index

� Spat Recruitment

� Growth

� Survival (including predation)

� Living density

Salinity vs. Flow (1999-2007 data)

Condition Index Growth and Survival

Quantify the ability of an area to support oyster growth (i.e., suitable water

Juvenile survival and

growth analyses

yield results related

to short-term survival suitable water quality, food availability). CI quantifies the overall health.

to short-term survival and long term potential to support oyster reefs

Condition Index

6.00

8.00

10.00

12.00

CI

0.00

2.00

4.00

CI

Piney Point Cattle Dock Bird Island Kitchel Key Tarpon Bay

Juvenile Growth – closed bag

35

40

45

50Iona Cove

Cattle Dock

Bird Island

Kitchel Key

0

5

10

15

20

25

30

Dec '07 Jan '08 Feb '08 Mar '08 Apr '08 May '08 Jun '08 Jul '08 Aug '08 Sep '08 Oct '08 Nov '08

Len

gth

(m

m)

Month

Tarpon Bay

PepperTree

Juvenile growth - closed

25

30

35

40

Iona Cove

0

5

10

15

20

Dec '07 Jan '08 Feb '08 Mar '08 Apr '08 May '08 Jun '08 Jul '08 Aug '08 Sep '08 Oct '08 Nov '08 Dec '08

Siz

e (

mm

)

Sampling month

Iona Cove

Cattle Dock

Bird Island

Kitchel Key

Tarpon Bay

PepperTree

Juvenile survival – closed bag

200

250

Iona Cove

Cattle Dock

0

50

100

150

Dec '07 Jan '08 Feb '08 Mar '08 Apr '08 May '08 Jun '08 Jul '08 Aug '08 Sep '08 Oct '08 Nov '08

# L

ivin

g o

yste

rs

Month

Cattle Dock

Bird Island

Kitchel Key

Tarpon Bay

PepperTree

Juvenile survival – open bag

150

200

250

Iona Cove

0

50

100

150

Dec '07 Jan '08 Feb '08 Mar '08 Apr '08 May '08 Jun '08 Jul '08 Aug '08 Sep '08 Oct '08 Nov '08 Dec '08

Siz

e (

mm

)

Sampling Time

Iona Cove

Cattle Dock

Bird Island

Kitchel Key

Tarpon Bay

PepperTree

Survival:

Disease

Juvenile survival and disease analyses 0.4

0.6

0.8

1

1.2

P.

ma

rin

us

inte

nsi

ty

disease analyses

yield results related

to short-term survival0

0.2

IC CD BI KK TBP

. m

ari

nu

s in

ten

sity

Sampling Location

P. marinus intensity

3.00

3.50

4.00

0.00

0.50

1.00

1.50

2.00

2.50

Infe

cti

on

in

ten

sit

y

Sampling time

Piney Point

Cattle Dock

Bird Island

Kitchel Key

Tarpon Bay

P. marinus prevalence

80

100

120

% o

f o

yste

rs i

nfe

cte

d

0

20

40

60

% o

f o

yste

rs i

nfe

cte

d

Piney Point Cattle Dock Bird Island

Kitchel Key Tarpon Bay

Figure 1: P erkinsus marinus infec tion prevalence (% inf ected oysters) in oyste rs from

Caloosaha tchee Estuary, FL. Lo cations Piney Point, C attle Dock, Bird Island , KitchelKey, and T arpon Bay are from up stream to downstream . Ten oysters per loca tion are

analyzed m onthly using Ray's flu id thioglycollate mediu m.

Reproduction

� Effects of water quality and substrate on long-term viability of reef

� Gonadal index: reproductive stage and qualitative estimate of fecundityestimate of fecundity

� Recruitment: estimates for next year class

� Management implications: timing of freshwater inflows

Spat Recruitment

200

250

300

0

50

100

150

200

Oct '00

Feb '01

Jun '01

Oct '01

Mar '02

Jul '02

Nov '02

Mar '03

July '03

Nov '03

Mar '04

Jul '04

Nov '04

Mar '05

Jul '05

Nov '05

Mar '06

Jul '06

Nov '06

Mar '07

Jul '07

Nov '07

Sp

at/

sh

ell

l

Sampling Month

Piney Point Cattle Dock Bird Island Kitchel Key Tarpon Bay PepperTree Point

Spat Recruitment – Caloosahatchee River

� Oysters spawn between May –October.

� Large freshwater 50.0

60.0

70.0

Sp

at

/ sh

ell

� Large freshwater releases flush larvae downstream or create unfavorable salinity conditions.

0.0

10.0

20.0

30.0

40.0

Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec

Sp

at

/ sh

ell

Sampling Month

IC CD BI KK TB PTP

Spat Recruitment

Reproduction

� Effects of water quality and substrate on long-term viability of reef

� Gonadal index: reproductive stage and qualitative estimate of fecundityestimate of fecundity

� Recruitment: estimates for next year class

� Management implications: timing of freshwater inflows

Gonadal Index

4.0

5.0

6.0

Gonadal In

dex

0.0

1.0

2.0

3.0

Gonadal In

dex

Sampling month

PP CD BI KK TB

Living Density

Dry Season Wet Season

2000

2500

1400

1600

1800

0

500

1000

1500

2000

Iona Cove

Cattle dock

Bird Island

Kitchel Key

Tarpon Bay

Dry '06

Dry '07

0

200

400

600

800

1000

1200

1400

Iona Cove

Cattle dock

Bird Island

Kitchel Key

Tarpon Bay

Wet '06

Wet '07

Living Density (2008)

1200

1400

1600

Liv

ing

oy

ste

rs /

sq

. m

.

0

200

400

600

800

1000

Iona Cove Cattle dock Bird Island Kitchel Key Tarpon Bay

Liv

ing

oy

ste

rs /

sq

. m

.

Sampling location

Caloosa 2008 Density Data (Average # oysters per square meter) Dry

Approach� What do we do with the data?

� The measurements we make will answer why and not just what is happening.

� Enables us to engage in adaptive management.� Enables us to engage in adaptive management.

� In addition to scientific evaluation of the cause and effect relationship, we need to communicate the results with resource managers and public

� Stoplight Indicator (Success (Green), Caution (Yellow) and Failure (Red).

� Caloosahatchee Estuary as an example

Stoplight Indicator � A communication tool that uses MAP performance

measures to grade an estuary’s response to anthropogenic or restoration inputs (Average of component score + trend score).

� Questions or decision rules are developed for each � Questions or decision rules are developed for each performance measure and translated as suitability curves.

� Suitability curve address:

� (1) Have we reached the restoration target, and

� (2) are we making progress toward targets?

� Finally, results are translated into a stoplight display (red, yellow, green)

Component Scores – Decision rules1. What is the current living density, in individuals per meter square, of oysters in the

Caloosahatchee estuary.

a. 0 - 200 Score: 0 Red

b. > 200 - 800 Score: 0.5 Yellow

c. > 800 - 4000 Score: 1.0 Green

2. What is the current condition index of the oysters in the Caloosahatchee estuary? Use the yearly

average.average.

a. 0 – 1.5 Score: 0 Red

b. > 1.5 – 3.0 Score: 0.5 Yellow

c. > 3.0 - 6.0 Score: 1.0 Green

3. What is the current gonadal condition of oysters in the Caloosahatchee estuary? Use the yearly

average.

a. 0 – 1 Score: 0 Red

b. >1 - 2 Score: 0.5 Yellow

c. >2 - 4 Score: 1 Green

Component Scores – decision rules4. What is the current spat recruitment of oysters (spat / shell) in the Caloosahatchee estuary?

a. 0 - 5 Score: 0 Red

b. > 5 - 20 Score: 0.5 Yellow

c. > 20 – 200 Score: 1.0 Green

5. What is the current growth of juvenile oysters in mm/month?

a. 0 – 1 Score: 0 Red

b. > 1.0 - 2.5 Score: 0.5 Yellowb. > 1.0 - 2.5 Score: 0.5 Yellow

c. > 2.5 - 5 Score: 1.0 Green

6. What is the prevalence of Perkinsus marinus (% of infected oysters) in oysters from the Caloosahatchee estuary?

Use the yearly average.

a. 0 - 20 Score: 1 Green

b. > 20 – 50 Score: 0.5 Yellow

c. > 50 - 100 Score: 0 Red

7. What is the intensity of Perkinsus marinus (scale 0-5) in oysters from the Caloosahatchee estuary? Use the yearly

average.

a. 0 - 1 Score: 1 Green

b. > 1 - 3 Score: 0.5 Yellow

c. > 3 – 5 Score: 0 Red

Trend score

Trend score – decision ruleTrend question

a. - slope Score: 0 Red

b. no slope Score: 0.5 Yellow

c. + slope Score: 1.0 Green

Index

Score

Stoplight Color

0.0-0.3 0 Red

>0.3-0.6 0.5 Yellow

>0.6-1.0 1.0 Green

Translation of component score and trend score into an index score

Caloosahatchee estuaryComponent Parameter Value Parameter

Value

Stoplight

Index Score Trend Trend Stop

light

Trend score Average Component

Score

Component

Stoplight

Oysters

Living Density

(per sq. m.)

1029 1 0.5 (1+0.5)/2=0.75

Condition Index 2.96 0.5 0.5 (0.5+0.5)/2=0.5Condition Index 2.96 0.5 ± 0.5 (0.5+0.5)/2=0.5

Spat Recruitment

per shell

6.43 0.5 ± 0.5 (0+0.5)/2=0.5

Juvenile growth

(mm/month)

2 0.5 ± 0.5 (0.5+0.5)/2=0.5

Perkinsus

marinus

prevalence

49.5 0.5 - 0 (0.5+0)/2=0.25

Perkinsus

marinus intensity

0.83 1 - 0 (1+0)/2=0.5

Geometric mean of oyster component scores (0.75 x 0.5 x 0.5 x 0.5 x 0.25 x 0.5)1/6 =

0.477

Final Eastern Oyster Index score = 0.5

St. Lucie EstuaryComponent Parameter

Value

Parameter

Value

Stoplight

Index Score

Trend Trend

Stop

Light

Trend

Score

Average

Component

Score

Component

Stoplight

Living Density

(per sq. m.)95.3 0 + 1 (1+0)/2=0.5

Condition

Index2.7 0.5 + 0.5 (0.5+0.5)/2=0.5

Spat

Recruitment 1.4 0 - 0 (0+0)/2=0

Recruitment

per shell

Juvenile

growth

(mm/month)

3.2 1 + 0.5 (1+0.5)/2=0.75

Perkinsus

marinus

prevalence

5.7 1 + 0 (1+0)/2=0.5

Perkinsus

marinus

intensity

0.04 1 + 0.5 (1+0.5)/2=0.75

Geometric mean of oyser component scores (0.5*0.5*0*1*0.5*1)1/6=0

Final Eastern Oyster Index Score = 0

Loxahatchee EstuaryComponent Parameter

Value

Parameter

Value

Stoplight

Index Score

Trend Trend

Stop

Light

Trend

Score

Average

Component

Score

Component

Stoplight

Living Density

(per sq. m.)168 0 + 1 (1+0)/2=0.5

Condition

Index3.1 1 + 0.5 (1+0.5)/2=0.75

Spat 3.8 0 + 1 (0+1)/2=0.5Spat

Recruitment

per shell

3.8 0 + 1 (0+1)/2=0.5

Juvenile

growth

(mm/month)

2.8 1 + 0.5 (1+0.5)/2=0.75

Perkinsus

marinus

prevalence

28.7 0.5 + 0 (0.5+0)/2=0.25

Perkinsus

marinus

intensity

0.22 1 + 0 (1+0)/2=0.5

Geometric mean of oyster component scores (0.5*0.75*0.5*0.75*0.25*0.5)1/6=0.03

Final Eastern Oyster Index Score = 0.03

Lake Worth LagoonComponent Parameter

Value

Parameter

Value

Stoplight

Index Score

Trend Trend

Stop

Light

Trend

Score

Average

Component

Score

Component

Stoplight

Living Density

(per sq. m.)172 0 - 0 (0+0)/2=0

Condition

Index3.4 1 + 1 (1+1)/2=1

Spat 3.1 0 + 0.5 (0+0.5)/2=0.25Spat

Recruitment

per shell

3.1 0 + 0.5 (0+0.5)/2=0.25

Juvenile

growth

(mm/month)

2.5 0.5 + 0.5 (0.5+0.5)/2=0.5

Perkinsus

marinus

prevalence

41.6 0.5 + 0 (0.5+0)/2=0.25

Perkinsus

marinus

intensity

0.32 1 + 0 (1+0)/2=0.5

Geometric mean of oyster component scores (0*1*0.25*0.5*0.25*0.5)1/6=0.0

Final Eastern Oyster Index Score = 0.0

Summary

�Freshwater releases from Lake Okeechobee decrease salinities at the samples sites by 3-6 ppt.

�Juvenile oysters at upstream locations with �Juvenile oysters at upstream locations with intermediate salinities showed higher growth, with the exception of Cattle Dock, a location that receives output from Cape Coral (water quality?)

Summary�Oysters in the Caloosahatchee Estuary spawn

continuously between April – October.

�High levels of freshwater flows during summer (spawning) months may flush out oyster larvae or reduce salinities to unfavorable levels.(spawning) months may flush out oyster larvae or reduce salinities to unfavorable levels.

� High salinities in 2007 resulted in poor spat recruitment and higher disease levels (as well as low survival due to predation?)

Summary

�Flows between 500 – 3000 CFS from Lake Okeechobee will result in optimum salinities at sampling locations (15 – 25 ppt).

�Stoplight indicator communication toll was developed. Can be adapted for other estuaries

�Caloosahatchee estuary is at “Caution”

Future directions� Integration of the data with HSI

� Inclusion of other factors influencing oyster responses

� Newer techniques that will enhance the sample size and power of analysesand power of analyses

� Addition / changing sampling locations

� Looking at why the indicator species is responding and not what it is doing.

� Adaptive management

Acknowledgements�Funding: South Florida Water Management

District; FGCU; USDOE; EPA.

�Technical / Field Help: Lesli Haynes, Amanda Bridges, Erin Dykes and numerous graduate and Bridges, Erin Dykes and numerous graduate and undergraduate students.