John Lake – Marine BiologistJohn Lake – Marine BiologistRIDFW-Marine Fisheries SectionRIDFW-Marine Fisheries Section

3 Ft. Wetherill Road3 Ft. Wetherill RoadJamestown, RI 02835Jamestown, RI 02835john.lake@dem.ri.govjohn.lake@dem.ri.gov

Young-of-the-Year Survey in RI Coastal Ponds

Purpose of SurveyPurpose of Survey

To monitor juvenile fish populations To monitor juvenile fish populations in Rhode Island coastal ponds and in Rhode Island coastal ponds and

estuaries, for the purpose of estuaries, for the purpose of forecasting recruitment in relation to forecasting recruitment in relation to

the spawning stock biomass of the spawning stock biomass of winter flounder and other winter flounder and other

recreationally important species.recreationally important species.

Survey FactsSurvey Facts Survey began in 1992Survey began in 1992

Data has been collected on 98 fish speciesData has been collected on 98 fish species Over 500,000 fish have been collected since Over 500,000 fish have been collected since

surveys inceptionsurveys inception Being expanded this yearBeing expanded this year

Winter Flounder ReproductionWinter Flounder Reproduction Males and females reach maturity at 3 years of ageMales and females reach maturity at 3 years of age Adults believed to show spawning site affinity, sub-Adults believed to show spawning site affinity, sub-

populations of winter flounder exist in RI waterspopulations of winter flounder exist in RI waters Spawning occurs in estuaries from January – MaySpawning occurs in estuaries from January – May Eggs clump together and rest on bottom (<1mm)Eggs clump together and rest on bottom (<1mm) Usually hatch 15 – 18 days after being releasedUsually hatch 15 – 18 days after being released When the larvae are 1/3 of an inch they have When the larvae are 1/3 of an inch they have

completely metamorphosedcompletely metamorphosed

Recruitment and PredationRecruitment and Predation

Spawning and settlement in near shore demersal Spawning and settlement in near shore demersal habitats makes eggs, larvae, and juveniles sensitive habitats makes eggs, larvae, and juveniles sensitive to disturbancesto disturbances

Egg, larval, and juvenile growth and survival are Egg, larval, and juvenile growth and survival are inversely related to increasing water temperatureinversely related to increasing water temperature

Predation rates increase with increasing temperature Predation rates increase with increasing temperature Increase in Sand Shrimp (Increase in Sand Shrimp (Crangon septimspinosaCrangon septimspinosa) )

predation is thought to have a large impact on egg predation is thought to have a large impact on egg mortality when water temperatures are elevatedmortality when water temperatures are elevated

Juvenile winter flounder and sand shrimp

Winter Flounder in the Coastal PondsWinter Flounder in the Coastal Ponds

Ponds are a breeding ground/nursery with repeat Ponds are a breeding ground/nursery with repeat spawners returning annuallyspawners returning annually

Juveniles believed to be relatively stationary with Juveniles believed to be relatively stationary with affinity to sites near spawning locationsaffinity to sites near spawning locations

Prefer sandy-silt bottom texturePrefer sandy-silt bottom texture Larval and juvenile stages feed on the eggs and Larval and juvenile stages feed on the eggs and

larval stages of various invertebrateslarval stages of various invertebrates Juveniles use eelgrass and other submerged aquatic Juveniles use eelgrass and other submerged aquatic

vegetation (SAV) habitats as a refuge from predationvegetation (SAV) habitats as a refuge from predation

Map of Sampling LocationsMap of Sampling Locations

Sampling ProcedureSampling Procedure

Beach Seine is set and hauled in a semicircle at each Beach Seine is set and hauled in a semicircle at each stationstation

Water quality data is collected at each station Water quality data is collected at each station (Temperature, Salinity, Dissolved Oxygen, Secci Depth)(Temperature, Salinity, Dissolved Oxygen, Secci Depth)

Finfish species are identified, counted, and measured Finfish species are identified, counted, and measured

Physical ParametersPhysical Parameters

Average Water Temperatures from Coastal Pond Survey by Month 1993 -2010

0

5

10

15

20

25

30

May Jun Jul Aug Sep Oct

Tem

p d

eg C

Average Physical Parameters from Coastal Pond Survey

0

10

20

30

40

1993

1995

1997

1999

2001

2003

2005

2007

2009

Year

Tem

p (

deg

C)

Sal

(p

pt)

D

O (

mg

/l)

Salinity

Temperature

Dissolved Oxygen

Target SpeciesTarget Species

AlewifeAlewife Black Sea Bass Black Sea Bass BluefishBluefish MenhadenMenhaden Scup Scup TautogTautog Winter FlounderWinter Flounder

Tautog Tautoga onitis

Recreationally Important Finfish Species Abundance Recreationally Important Finfish Species Abundance Indices in Coastal PondsIndices in Coastal Ponds

Bluefish

00.5

11.5

22.5

33.5

4

1994

1995

1996

1997

1998

1999

2000

2001

2002

2003

2004

2005

2006

2007

2008

2009

2010

Year

CP

UE

(fi

sh

/hau

l)

Black Sea Bass

0

0.5

1

1.5

2

2.5

1994

1995

1996

1997

1998

1999

2000

2001

2002

2003

2004

2005

2006

2007

2008

2009

2010

Year

CP

UE

(fi

sh

/hau

l)Tautog

0

1

2

3

4

5

6

71994

1995

1996

1997

1998

1999

2000

2001

2002

2003

2004

2005

2006

2007

2008

2009

2010

Year

CP

UE

(fi

sh

/hau

l)

Alewife

0

0.5

1

1.5

2

2.5

3

3.51994

1995

1996

1997

1998

1999

2000

2001

2002

2003

2004

2005

2006

2007

2008

2009

2010

Year

CP

UE

(fi

sh

/hau

l)

Menhaden

0

100

200

300

400

500

600

700

1994

1995

1996

1997

1998

1999

2000

2001

2002

2003

2004

2005

2006

2007

2008

2009

2010

Year

CP

UE

(fi

sh

/hau

l)Scup

0

0.1

0.2

0.3

0.4

0.5

1994

1995

1996

1997

1998

1999

2000

2001

2002

2003

2004

2005

2006

2007

2008

2009

2010

Year

CP

UE

(fi

sh

/hau

l)

May 2010 Winter Flounder Length Frequency

0

2

4

6

8

10

0

1.1

2.2

3.3

4.4

5.5

6.6

7.7

8.8

9.9 11

12.1

13.2

14.3

15.4

16.5

17.6

Length (cm)

Fre

qu

ency

July 2010 Winter Flounder Length Frequency

0

5

10

15

20

25

0

1.1

2.2

3.3

4.4

5.5

6.6

7.7

8.8

9.9 11

12.1

13.2

14.3

15.4

16.5

17.6

Length (cm)

Fre

qu

ency

September 2010 Winter Flounder Length Frequency

0

1

2

3

4

5

0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18

Length (cm)

Fre

qu

ency

June 2010 Winter Flounder Length Frequency

0

2

4

68

10

12

14

0

1.1

2.2

3.3

4.4

5.5

6.6

7.7

8.8

9.9 11

12.1

13.2

14.3

15.4

16.5

17.6

Length (cm)

Fre

qu

ency

August 2010 Winter Flounder Length Frequency

0

5

10

15

20

25

30

0

1.1

2.2

3.3

4.4

5.5

6.6

7.7

8.8

9.9 11

12.1

13.2

14.3

15.4

16.5

17.6

Length (cm)

Fre

qu

ency

October 2010 Winter Flounder Length Frequency

0

0.5

1

1.5

2

2.5

3

3.5

0

1.1

2.2

3.3

4.4

5.5

6.6

7.7

8.8

9.9 11

12.1

13.2

14.3

15.4

16.5

17.6

Length (cm)

Fre

qu

ency

Coastal Pond Winter Flounder Length Frequencies

2010 Winter Flounder Frequency from Coastal Pond Survey2010 Winter Flounder Frequency from Coastal Pond Survey

2010 Winter Flounder Frequency by Pond

0

50

100

150

200

250

May

June Ju

ly

Augus

t

Septe

mbe

r

Octobe

r

Month

Fre

qu

ency

CP

NR

PJ

QP

WP

Coastal Pond Winter Flounder Abundance Indices (fish/haul)Coastal Pond Winter Flounder Abundance Indices (fish/haul)

CPUE of Winter Flounder from Coastal Pond Survey by Pond

0

10

20

30

40

50

60

1994

1996

1998

2000

2002

2004

2006

2008

2010

Year

CP

UE

(fi

sh/h

aul)

CP

NR

PJ

QP

WP

Average CPUE of Winter Flounder from Coastal Pond Survey

05

10152025303540

1994

1995

1996

1997

1998

1999

2000

2001

2002

2003

2004

2005

2006

2007

2008

2009

2010

Year

CP

UE

(fi

sh/h

aul)

CPUE of Winter Flounder from Trawl and Seine Surveys

0102030405060

1999

2001

2003

2005

2007

2009

Year

CP

UE

(fi

sh /

hau

l)

Coastal PondSurvey

NarragansettBay Survey

RIDFW SpringTrawl

URIGSO Trawl

Comparison of CPS Winter Flounder Comparison of CPS Winter Flounder Abundance Indices to other surveysAbundance Indices to other surveys

CPUE of Winter Flounder from RIDFW Fyke Net and Seine Survey in Point Judith Pond

0.00

10.00

20.00

30.00

40.00

50.00

1999 2001 2003 2005 2007 2009

Year

CP

UE

(fi

sh/h

aul)

Fyke

CPS

Point Judith Pond Adult and Juvenile IndicesPoint Judith Pond Adult and Juvenile Indices

• Point Judith Pond was closed to harvest and possession of Winter Flounder on April 8, 2011

Funded by Rhode Island Division of Fish and Wildlife, USFW Federal Aid to Sport Fish Restoration Funded by Rhode Island Division of Fish and Wildlife, USFW Federal Aid to Sport Fish Restoration

Grant No: F-61-R-17Assessment of Recreationally Important Finfish

Stocks in Rhode Island Coastal Ponds