Tampa Bay Tidal Tributaries

Tampa Bay Tidal Tributaries

Tidal Tributary Study Final Report Water Quality, Sediment Chemistry, Benthic Macrofauna, and Watershed Characterization

September 2007

Tidal Tributary Study Summary Report Water Quality, Sediment Chemistry, Benthic Macrofauna, and Watershed Characterization

Edward T. Sherwood, David J. Karlen, Thomas L. Dix, Barbara K. Goetting, Sara E. Markham, Anthony Chacour, Melissa Miller

September 2007

Environmental Protection Commission of Hillsborough County Environmental Resource Management Division 3629 Queen Palm Dr. Tampa, FL 33619

ii

TABLE OF CONTENTS LIST OF TABLES ........................................................................................................................ v LIST OF FIGURES ..................................................................................................................... vi LIST OF APPENDICES ............................................................................................................. ix 1.

INTRODUCTION................................................................................................................. 1

2.

METHODS ............................................................................................................................ 3 2.1 STUDY SITES ................................................................................................................. 3 2.2 MONTHLY WATER QUALITY MONITORING ............................................................. 3 2.3 SEASONAL BENTHIC BIOTA & SEDIMENT QUALITY MONITORING .................... 4 2.4 ANALYSIS ....................................................................................................................... 4 2.4.1 Water Quality Monitoring Analysis........................................................................ 4 2.4.2 Sediment Quality and Benthic Biota Analysis........................................................ 5

3.

RESULTS .............................................................................................................................. 7 3.1 WATER QUALITY MONITORING RESULTS................................................................ 7 3.1.1 Physical Water QualityParameters ......................................................................... 7 3.1.1.1 Second Order Tributary Systems (Alafia & Little Manatee River)..................... 7 3.1.1.2 First Order Tributary Systems (Feather Sound & Terra Ceia Bay)................... 7 3.1.2 Nutrient Concentrations .......................................................................................... 8 3.1.2.1 Second Order Tributary Systems (Alafia & Little Manatee River)..................... 8 3.1.2.2 First Order Tributary Systems (Feather Sound & Terra Ceia Bay)................... 8 3.1.3 Water Quality Biological Indicators ....................................................................... 9 3.1.3.1 Second Order Tributary Systems (Alafia & Little Manatee River)..................... 9 3.1.3.2 First Order Tributary Systems (Feather Sound & Terra Ceia Bay)................... 9 3.2 BENTHIC MONITORING RESULTS ........................................................................... 10 3.2.1 Physical Benthic Sampling Conditions................................................................. 10 3.2.1.1 Second Order Tributary Systems (Alafia & Little Manatee River)................... 10 3.2.1.1.1 Benthic Sampling Bottom Water Quality ................................................... 10 3.2.1.1.2 Benthic Sampling Sediment Quality........................................................... 10 3.2.1.2 First Order Tributary Systems (Feather Sound & Terra Ceia Bay)................. 13 3.2.1.2.1 Benthic Sampling Bottom Water Quality ................................................... 13 3.2.1.2.2 Benthic Sampling Sediment Quality........................................................... 14 3.2.2 Benthic Macrofauna.............................................................................................. 16 3.2.2.1 Second Order Tributary Systems (Alafia & Little Manatee River)................... 16 3.2.2.1.1 Mainstem Alafia River and its Second Order Tributaries ............................. 16 3.2.2.1.2 Mainstem Little Manatee River and its Second Order Tributaries ................ 18 3.2.2.2 First Order Tributary Systems (Feather Sound & Terra Ceia Bay)................. 19 3.2.2.2.1 Feather Sound/Old Tampa Bay and Grassy Creek ........................................ 19 3.2.2.2.2 Terra Ceia Bay and its First Order Tributaries .............................................. 21

iii

3.3 WATERSHED CHARACTERIZATION & MONITORING LINKS ............................... 23 3.3.1 Watershed Metrics ................................................................................................ 23 3.3.1.1 Second Order Tributary Systems (Alafia & Little Manatee River)................... 23 3.3.1.2 First Order Tributary Systems (Feather Sound & Terra Ceia Bay)................. 23 3.3.2 Watershed Links to Monitoring Results ............................................................... 23 4.

LITERATURE CITED ...................................................................................................... 25

5.

TABLES............................................................................................................................... 28

6.

FIGURES............................................................................................................................. 48

APPENDIX A:............................................................................................................................. 82 APPENDIX B:........................................................................................................................... 117 APPENDIX C:........................................................................................................................... 152 APPENDIX D:........................................................................................................................... 158 APPENDIX E:........................................................................................................................... 203 APPENDIX F: ........................................................................................................................... 228 APPENDIX G: .......................................................................................................................... 237

iv

LIST OF TABLES Table 1: Table 2: Table 3: Table 4: Table 5: Table 6: Table 7:

Table 8: Table 9: Table 10: Table 11:

Table 12: Table 13: Table 14: Table 15: Table 16: Table 17: Table 18: Table 19: Table 20:

Monthly tidal tributary water quality monitoring effort during 2006....................... 29 Number of unique water quality monitoring sampling events during 2006 within and in the vicinity of the Tidal Tributary projects’ sampling universe. Italicized tributaries indicate priority sample areas for this project.......................... 30 Benthic quality monitoring data descriptors and cut-offs......................................... 31 Landscape Development Intensity Index (LDI) coefficients in relation to Florida Land Use Land Cover Classification Codes (FLUCCSODE) (Adapted from Brown and Vivas 2005).................................................................... 32 Summary of physical water quality monitoring results in the Alafia River (AR), Little Manatee River (LMR), Feather Sound (FS), and Terra Ceia Bay (TCB) watersheds during 2006. ........................................................................................... 33 Results of crossed general linear model testing for general and individual differences between second order tidal tributaires and the mainstem rivers to which they drain (Alafia and Little Manatee River)............................................. 34 Results of nested general linear model testing for general differences between second order tidal tributaires draining to the Alafia (a-priori disturbed) and Little Manatee Rivers (a-priori less disturbed) and first order tributaries draining to Feather Sound (a-priori disturbed) and Terra Ceia Bay (a-priori less disturbed). .... 35 Results of crossed general linear model testing for general and individual differences between first order tidal tributaires and the embayments to which they drain (Feather Sound and Terra Ceia Bay)............................................. 36 Summary of nutrient results in the Alafia River (AR), Little Manatee River (LMR), Feather Sound (FS), and Terra Ceia Bay (TCB) watersheds during 2006. . 37 Summary of biological water quality monitoring results in the Alafia River (AR), Little Manatee River (LMR), Feather Sound (FS), and Terra Ceia Bay (TCB) watersheds during 2006................................................................................. 38 Tidal tributary benthic quality sampling information. EPCHC refers to the collections made by the Environmental Protection Commission of Hillsborough County, while MCEMD refers to collections made by the Manatee County Environmental Management Department. ................................................................ 39 Summary statistics for bottom water quality and sediment composition for benthic sampling sites in the Alafia and Little Manatee River watersheds. ............. 40 Summary statistics for bottom water quality and sediment composition for benthic sampling sites in the Feather Sound and Terra Ceia Bay watersheds.......... 41 Summary statistics for benthic community indices for benthic sampling sites in the Alafia and Little Manatee River watersheds........................................... 42 Alafia River tidal tributary benthic relative abundance............................................ 43 Little Manatee River tidal tributary benthic relative abundance. ............................. 44 Summary statistics for benthic community indices for benthic sampling sites in the Feather Sound and Terra Ceia Bay watersheds. ..................................... 45 Feather Sound / Old Tampa Bay tidal tributary benthic relative abundance............ 46 Terra Ceia Bay tidal tributary benthic relative abundance. ...................................... 46 Summary of watershed metrics for the tidal tributaries............................................ 47

v

LIST OF FIGURES Figure 1:

Figure 2: Figure 3:

Figure 4:

Figure 5: Figure 6: Figure 7: Figure 8: Figure 9: Figure 10: Figure 11: Figure 12: Figure 13: Figure 14: Figure 15: Figure 16: Figure 17: Figure 18: Figure 19: Figure 20: Figure 21: Figure 22: Figure 23: Figure 24: Figure 25:

Overview map showing the location of the select tidal tributary study areas. The tributaries draining to Feather Sound and Terra Ceia Bay were considered first order tributaries. The tributaries draining to the Alafia and Little Manatee Rivers were considered second order tributaries. Tributaries in the Alafia River and Feather Sound watersheds were considered a priori more disturbed...................................................................................................................... 49 Total annual, wet season, and dry season rainfall conditions in the tidal tributary watersheds over the period of record (1915-2006) and during 2006 (Adapted from SWFWMD 2007). ........... 50 Aerial maps showing sample sites in the Alafia (top, a priori disturbed) and Little Manatee (bottom, a priori less disturbed) Rivers. Water quality (yellow circle) and benthic quality (red triangle) sites monitored in 2006 for the tidal tributary study are depicted. Also depicted are additional monitoring sites adjacent to the tributary study areas...................................................... 51 Aerial maps showing sample sites in Feather Sound (top, a priori disturbed) and Terra Ceia Bay (bottom, a priori less disturbed). Water quality (yellow circle) and benthic quality (red triangle) sites monitored in 2006 for the tidal tributary study are depicted. Also depicted are additional monitoring sites adjacent to the tributary study areas...................................................... 52 Alafia River and Little Manatee River tidal tributary benthic sample depths. ................................. 53 Alafia River and Little Manatee River tidal tributary benthic sampling bottom temperatures. ....... 53 Alafia River and Little Manatee River tidal tributary benthic sampling bottom pH. ....................... 54 Alafia River and Little Manatee River tidal tributary benthic sampling bottom salinity. ................ 54 Alafia River and Little Manatee River tidal tributary benthic sampling bottom dissolved oxygen. 55 Alafia River and Little Manatee River tidal tributary benthic sampling sediment composition (% silt + clay)................................................................................................................................ 55 Alafia River area tidal tributary Cd: Al regression with 95% prediction intervals. Dash lines represent TEL (lower) and PEL (upper) for Cd............................................................................ 56 Alafia River area tidaltributary Se:Al regression with 95% prediction intervals. ........................ 56 Alafia River area tidal tributary As: Al regression with 95% prediction intervals. Dash lines represent TEL (lower) and PEL (upper) for As. ........................................................................... 57 Little Manatee River area tidal tributary Cd:Al regression with 95% prediction intervals. Dash lines represent TEL (lower) and PEL (upper) for Cd. ......................................................... 57 Feather Sound/Old Tampa Bay and Terra Ceia Bay tidal tributary benthic sampling depths...... 58 Feather Sound/Old Tampa Bay and Terra Ceia Bay tidal tributary benthic bottom temperature. 58 Feather Sound/Old Tampa Bay and Terra Ceia Bay tidal tributary benthic bottom pH............... 59 Feather Sound/Old Tampa Bay and Terra Ceia Bay tidal tributary benthic bottom salinity........ 59 Feather Sound/Old Tampa Bay and Terra Ceia Bay tidal tributary benthic bottom dissolved oxygen........................................................................................................................................... 60 Feather Sound/Old Tampa Bay and Terra Ceia Bay tidal tributary benthic sediment composition (% silt+clay). ............................................................................................................ 60 Grassy Creek and Old Tampa Bay Cd:Al regression with 95% prediction intervals. Dash lines represent TEL (lower) and PEL (upper) for Cd. .................................................................. 61 Alafia River and Little Manatee River tidal tributary benthic species richness. .......................... 62 Alafia River and Little Manatee River tidal tributary benthic abundance.................................... 62 Alafia River and Little Manatee River tidal tributary benthic diversity....................................... 63 Alafia River and Little Manatee River tidal tributary: Tampa Bay Benthic Index. Dash lines indicate cut-offs for Healthy (>87) and Degraded (87) and Degraded ( 30.0 PSU Euhaline Sediment Silt/Clay Types < 1.70% Coarse 1.70-4.51% Medium 4.51-11.35% Fine 11.35 – 25.95% Very Fine > 25.95% Mud Tampa Bay Benthic Index 87 Healthy

31

Table 4:

Landscape Development Intensity Index (LDI) coefficients in relation to Florida Land Use Land Cover Classification Codes (FLUCCSODE) (Adapted from Brown and Vivas 2005).

LDI Coefficient

LDI Description

FLUCCSCODE 4100

1

Natural Land/Open Water

FLUCCSCODE Description UPLAND CONIFEROUS FOREST

4110

PINE FLATWOODS

4120

LONGLEAF PINE - XERIC OAK

4200

UPLAND HARDWOOD FORESTS - PART 1

4340

HARDWOOD CONIFER MIXED

5200

LAKES

6100

WETLAND HARDWOOD FORESTS

6110

BAY SWAMPS

6120

MANGROVE SWAMPS

6150

STREAM AND LAKE SWAMPS (BOTTOMLAND)

6200

WETLAND CONIFEROUS FORESTS

6210

CYPRESS

6300

WETLAND FORESTED MIXED

6410

FRESHWATER MARSHES

6420

SALTWATER MARSHES

6430

WET PRAIRIES

6440

EMERGENT AQUATIC VEGETATION

6530

INTERMITTENT PONDS

6600

SALT FLATS

2200

TREE CROPS

4400

TREE PLANTATIONS

1.58

Tree Plantations

1.83

Recreational/Open Space (LowIntensity)

1800

RECREATIONAL

1900

OPEN LAND

3.31

Pastureland (Mean-Intensity Index)

3300

MIXED RANGELAND

3.41

Low-Intensity Pasture (with Livestock)

2100

CROPLAND AND PASTURELAND

4.11

General Agriculture (Mean Citrus & Row Crops)

2400

NURSERIES AND VINEYARDS

2550

TROPICAL FISH FARMS

2600

OTHER OPEN LANDS

4.38

Recreational/Open Space (MeanIntensity Index)

3100

HERBACEOUS

3200

SHRUB AND BRUSHLAND

7400

DISTURBED LAND

4.54

Row Crops

2140

ROW CROPS

6.79

Single Family Residential (Low-density)

1100

RESIDENTIAL LOW DENSITY < 2 DWELLING UNITS

6.92

Recreational/Open Space (HighIntensity)

1820

GOLF COURSES

2300

FEEDING OPERATIONS

2500

SPECIALTY FARMS

7.47

Single Family Residential (Mediumdensity)

1200

RESIDENTIAL MED DENSITY 2->5 DWELLING UNIT

7.55

Single Family Residential (High-density)

1300

RESIDENTIAL HIGH DENSITY

7.81

Transportation (Low-Intensity)

8100

TRANSPORTATION

Commercial (Low-Intensity)

1400

COMMERCIAL AND SERVICES

Institutional

1700

INSTITUTIONAL

1500

INDUSTRIAL

1600

EXTRACTIVE

8200

COMMUNICATIONS

8300

UTILITIES

7

8 8.07

8.32

Agriculture (High-Intensity)

Industrial

32

Table 5:

Waters hed

AR

LMR

FS

TCB

Summary of physical water quality monitoring results in the Alafia River (AR), Little Manatee River (LMR), Feather Sound (FS), and Terra Ceia Bay (TCB) watersheds during 2006. Mean Water Column

Depth (m)

Tributary or Area

Mean Water Column Salinity (PSU)

Temperature (oC)

Bottom Dissolved Oxygen (mg/L)

N

Mean

Stderr

Min Max

N

Mean

Stderr

Max

N

Mean

Stderr

Min

Max

N

Mean

Stderr

Min

Max

N

Mean

Stderr

Min

Max

Mainstem Alafia River Dog Leg Creek

153

1.5

0.08

0.1

5.0

23

24.0

0.99

14.4 30.7

23

14.4

1.55

3.6

26.3

23

7.0

0.75

0.6

13.0

23

2.99

0.54

0.07

8.29

12

1.2

0.11

0.6

2.0

12

24.2

1.00

18.5 28.9

12

1.7

0.40

0.7

5.1

12

0.8

0.18

0.1

2.1

12

4.32

0.91

0.15 10.16

Question Mark Creek

12

0.9

0.08

0.6

1.4

12

25.2

1.51

15.2 31.9

12

10.8

1.18

4.5

17.8

12

5.0

1.01

0.7

10.0

12

4.78

0.87

0.14

Rice Creek

16

0.4

0.07

0.1

0.9

16

23.0

1.06

14.5 29.0

12

1.4

0.71

0.1

7.3

6

0.3

0.15

0.0

0.9

8

9.17

1.63

5.43 19.73

Riverview Park West Creek

12

0.6

0.08

0.2

1.0

12

24.6

1.42

15.9 31.7

12

2.7

0.82

0.2

8.2

11

1.3

0.67

0.0

7.8

11

6.20

1.22

2.02 14.58

Mainstem Little Manatee River

12

2.4

0.16

1.3

3.1

12

24.2

1.54

13.5 31.2

12

14.8

1.66

0.9

23.5

12

0.7

0.22

0.0

1.9

12

5.15

0.52

3.28

8.60

Curiosity Creek

28

1.1

0.13

0.2

3.2

28

22.7

0.94

12.0 30.2

24

3.6

0.94

0.2

15.3

24

0.3

0.16

0.0

3.8

26

4.77

0.38

0.35

8.07

Wildcat Creek

28

0.6

0.04

0.2

1.0

28

23.7

0.95

13.0 30.7

24

9.3

1.35

0.3

22.3

21

1.0

0.43

0.0

8.3

21

4.43

0.16

3.43

6.71

Other Creeks draining to LMR

7

0.2

0.03

0.1

0.3

7

21.2

1.57

15.2 25.9

.

.

.

.

.

.

.

.

.

.

.

.

.

.

.

Feather Sound/Old Tampa Bay

137

1.5

0.08

0.1

4.0

137

23.9

0.43

11.8 32.9 137

24.5

0.20

19.2 30.7 121

0.1

0.01

0.0

0.9

123

6.85

0.11

3.61

9.68

Grassy Creek

23

0.5

0.05

0.2

1.0

23

22.8

0.93

16.7 29.9

23

22.4

0.50

17.5 25.2

20

0.0

0.02

0.0

0.4

21

1.91

0.18

0.45

3.88

Other Creeks draining to FS

10

0.2

0.04

0.0

0.4

10

25.6

1.45

19.5 33.8

10

0.7

0.10

0.3

.

.

.

.

.

.

.

.

.

.

Terra Ceia Bay

12

1.9

0.26

0.3

3.0

.

.

.

.

.

.

.

.

.

.

.

.

.

.

.

.

.

.

Frog Creek

22

0.5

0.06

0.1

1.0

24

24.5

0.79

18.0 31.0

24

17.6

1.90

0.5

29.6

6

1.4

1.12

0.0

7.0

22

5.50

0.17

3.20

6.90

McMullen Creek

11

0.4

0.11

0.1

1.2

12

24.1

1.11

19.0 30.7

12

17.6

2.10

3.2

26.8

3

0.1

0.10

0.0

0.3

11

5.35

0.34

3.00

7.70

Waters hed

AR

LMR

FS

.

.

Secchi Depth (m)

Tributary or Area

Color (PCU)

Min Max

1.4

Turbidity (NTU)

N

Mean

Stderr

N

Mean

Stderr

N

Mean

Stderr

Mean

Stderr

Min

Max

148

0.9

0.05

0.2

2.5

160

51

4

5

200

23

4.3

0.54

1.5

11.5 160

9.1

0.59

1.0

41.0

12

0.9

0.07

0.5

1.2

12

23

4

10

54

12

6.3

0.99

2.4

12.5

12

14.2

3.27

3.0

44.0

Question Mark Creek

12

0.7

0.05

0.4

1

12

28

4

12

63

12

12.4

3.46

3.1

41.2

12

26.1

7.55

3.5

94.5

Rice Creek

16

0.4

0.06

0.1

0.8

16

44

6

13

94

12

6.3

1.42

1.4

16.4

12

12.8

4.42

1.0

52.0

Riverview Park West Creek

12

0.4

0.06

0.2

0.7

12

32

6

13

74

12

10.5

2.89

1.6

36.0

12

23.8

6.35

4.0

67.0

Mainstem Little Manatee River

12

1.4

0.10

0.9

1.9

12

36

8

15

115

12

2.3

0.24

1.7

4.9

12

6.2

0.41

4.0

9.0

Curiosity Creek

28

0.8

0.07

0.2

1.9

28

54

8

23

149

24

3.3

0.26

2.0

7.0

24

5.1

0.63

2.0

14.0

Wildcat Creek

27

0.6

0.04

0.2

0.9

28

47

5

19

100

24

3.5

0.23

1.6

5.5

24

9.1

1.01

2.0

24.0

Other Creeks draining to LMR

7

0.2

0.03

0.1

0.3

7

52

8

32

95

.

.

.

.

.

.

.

.

.

.

Feather Sound/Old Tampa Bay

136

1.3

0.05

0.1

3.1

30

8

1

5

17

137

2.1

0.12

0.6

8.4

117

14.5

1.18

2.0

48.0

Grassy Creek

23

0.5

0.05

0.2

1

23

22

1

11

35

23

3.5

0.57

1.4

13.2

20

11.0

1.38

5.0

32.0

.

.

.

.

.

.

.

.

.

.

8

2.7

0.46

1.1

4.9

8

5.3

1.26

1.0

11.0

Terra Ceia Bay

3

2.0

0.54

1

2.8

11

35

5

16

65

12

2.6

0.40

0.4

5.1

12

37.6

21.50

6.2

272.0

Frog Creek

24

0.5

0.05

0.1

1

24

99

9

32

200

24

5.2

0.36

1.6

9.5

24

20.6

5.26

4.0

130.0

McMullen Creek

12

0.4

0.10

0.1

1.2

12

112

13

58

180

12

10.4

3.74

3.3

50.0

12

30.5

14.61

7.6

190.0

33

Min Max

Total Suspended Solids (mg/L)

Mainstem Alafia River Dog Leg Creek

Other Creeks draining to FS

TCB

Min

Water Column Stratification (Sigma T Difference)

Min Max

N

9.03

Table 6:

Results of crossed general linear model testing for general and individual differences between second order tidal tributaries and the mainstem rivers to which they drain (Alafia and Little Manatee River).

2nd Order Alafia Tributaries (Question Mark, Riverview Park West, Rice, and Dog Leg Creeks) vs. Mainstem Alafia River

Depth Stratification Temperature Salinity Bottom D.O.

River>Tributaries Tributaries 0.1 River>Tributaries River 0.0008

No Difference No Difference No Difference No Difference No Difference

0.0761 >0.1 >0.1 >0.1 >0.1

Riverview Park West Creek (RP) vs. Alafia River (AR) AR>RP AR>RP No Difference AR>RP RP>AR

Color Turbidity TSS

River>Tributaries 0.0048 Tributaries>River 0.0066 Tributaries>River QC QC>AR QC>AR

0.0641 0.0026 AR RP>AR

>0.1 0.0273 0.1 >0.1 >0.1

AR>DC No Difference No Difference

0.0207 >0.1 >0.1

Total Nitrogen DIN DON Total Phosphorus SRP

Tributaries>River River>Tributaries . No Difference River>Tributaries

0.0004 0.077 . >0.1 0.0002

No Difference AR>QC . No Difference No Difference

>0.1 0.0853 . >0.1 >0.1

RP>AR No Difference . RP>AR No Difference

0.1 . 0.0829 0.9989

RC>AR No Difference . RC>AR AR>RC

0.0808 >0.1 . 0.0003 0.1 >0.1 . >0.1 >0.1

Chlorophyll-a Fecal coliform Enterococci

Tributaries>River River 0.096 No Difference >0.1

QC>AR No Difference No Difference

0.0312 >0.1 >0.1

RP>AR No Difference No Difference

0.0002 >0.1 >0.1

RC>AR RC>AR RC>AR

0.0029 0.0206 0.0007

No Difference No Difference No Difference

>0.1 >0.1 >0.1

Wildcat Creek (WC) vs. Little Manatee River (LMR)

p-value

Curiosity Creek (CC) vs. Little Manatee River (LMR)

Parameter

General Result

General Result

2nd Order Little Manatee River Tributaries (Wildcat, Curiosity, & Other Creeks Sampled) vs. Mainstem Little Manatee River

Within Tributaries vs. Areas to Which they Drain

Type of Comparison Comparison

p-value

p-value

Question Mark Creek (QC) vs. p-value Alafia River (AR)

Rice Creek Dog Leg Creek p-value (RC) vs. Alafia p-value (DC) vs. Alafia p-value River (AR) River (AR) 0.0025 0.1 RC AR>RC No Difference AR>RC RC>AR

0.1 DC 0.1 No Difference >0.1 DC Tributaries 0.1 No Difference >0.1 River>Tributaries 0.1

LMR>WC No Difference No Difference LMR>WC No Difference

0.1 >0.1 0.0134 >0.1

LMR>CC No Difference No Difference LMR>CC No Difference

0.1 >0.1 0.1

LMR>OC . No Difference . .

0.1 . .

Color Turbidity TSS

No Difference Tributaries>River No Difference

>0.1 0.0056 >0.1

No Difference WC>LMR WC>LMR

>0.1 0.0123 0.0502

No Difference CC>LMR No Difference

>0.1 0.0303 >0.1

No Difference . .

>0.1 . .


Tributaries>River No Difference . Tributaries>River Tributaries>River

0.0037 >0.1 . 0.0004 0.0014

No Difference No Difference . No Difference No Difference

>0.1 >0.1 . >0.1 >0.1

CC>LMR No Difference . CC>LMR CC>LMR

0.0009 >0.1 . LMR . OC>LMR No Difference

0.0005 0.006 . 0.0845 >0.1


No Difference Tributaries>River No Difference

>0.1 0.0059 >0.1

No Difference WC>LMR No Difference

>0.1 0.0458 >0.1

No Difference CC>LMR No Difference

>0.1 0.0331 >0.1

No Difference OC>LMR No Difference

>0.1 0.0297 >0.1

34

General Result

p-value

Significant Variation Among Tributaries?

Significant Seasonal Variation?

2nd Order Alafia River Tributaries (Question Mark, Riverview Park West, Rice, and Dog Leg Creeks) vs. 2nd Order Little Manatee River Tributaries (Wildcat, Curiosity, & Other Creeks Sampled)

Between Disturbed vs. Undisturbed Systems

Type of Comparison

Results of nested general linear model testing for general differences between second order tidal tributaries draining to the Alafia (a-priori disturbed) and Little Manatee Rivers (a-priori less disturbed) and first order tributaries draining to Feather Sound (a-priori disturbed) and Terra Ceia Bay (a-priori less disturbed).

Depth Stratification Temperature Salinity Bottom D.O.

No Difference No Difference No Difference No Difference No Difference

0.6564 0.429 0.0801 0.5776 0.3401

Yes (pFS

0.1053 0.5058 . 0.0473 0.0288

Yes (p=0.0077) Yes (p=0.0087) . No (p=0.2521) No (p=0.3250)

No (p=0.1650) No (p=0.5676) . Yes (p=0.0381) Yes (p=0.0526)


No Difference No Difference No Difference

0.6496 0.5429 0.5278

Yes (pTributaries Bay>Tributaries No Difference Bay>Tributaries Bay>Tributaries

0.1 GC No Difference FS>GC FS>GC

0.1 0.0003 OC . No Difference FS>OC .

0.1 Bay Tributaries>Bay Bay>Tributaries

FS No Difference

OC

. >0.1 0.0638


Tributaries>Bay Tributaries>Bay . No Difference Tributaries>Bay

FS GC>FS . GC>FS GC>FS

OC

>0.1 Bay Tributaries>Bay

>0.1 FS

>0.1 0.0005 FS OC>FS OC>FS

Tributaries . . . .

FC . . . .

MC . . . .

Bay Tributaries>Bay No Difference

0.1

FC>TCB No Difference No Difference

0.1 >0.1

MC>TCB MC>TCB No Difference

0.1


Tributaries>Bay No Difference . No Difference .

0.0142 >0.1 . >0.1 .

FC>TCB No Difference . FC>TCB .

0.0689 >0.1 . 0.0854 .

MC>TCB No Difference . MC>TCB .

0.0044 >0.1 . 0.0341 .

No Difference . .

>0.1 . .

No Difference . .

>0.1 . .

No Difference . .

>0.1 . .

Parameter

Parameter 1st Order Tributaries (Frog & McMullen Creeks) vs. Terra Ceia Bay

Within Tributaries vs. Areas to Which they Drain

Type of Comparison Comparison


36

Other Creeks (OC) vs. Feather p-value Sound (FS)

Table 9:

Waters hed

Tributary or Area

Summary of nutrient results in the Alafia River (AR), Little Manatee River (LMR), Feather Sound (FS), and Terra Ceia Bay (TCB) watersheds during 2006.

Dissolved Inorganic Nitrogen (mg/L)

Mainstem Alafia River Dog Leg Creek Question Mark Creek Rice Creek Riverview Park West Creek

N Mean 160 0.6 12 0.7 12 0.4 16 0.5 12 0.6

LMR

Mainstem Little Manatee River Curiosity Creek Wildcat Creek Other Creeks draining to LMR

12 28 28 7

0.2 0.5 0.1 1.1

0.03 0.10 0.01 0.65

0.0 0.0 0.0 0.0

0.3 2.4 0.2 4.8

. 24 24 .

FS

Feather Sound/Old Tampa Bay Grassy Creek Other Creeks draining to FS

135 23 8

0.0 0.1 0.3

0.00 0.01 0.07

0.0 0.0 0.1

0.1 0.2 0.6

Terra Ceia Bay Frog Creek McMullen Creek

2 19 10

0.1 0.4 0.2

0.04 0.06 0.08

0.1 0.1 0.1

0.1 1.1 0.9

AR

TCB

Stderr 0.03 0.10 0.07 0.06 0.09

Dissolved Organic Nitrogen (mg/L)

Min Max N Mean 0.0 1.3 . . 0.1 1.1 12 0.5 0.0 0.9 12 0.7 0.1 1.0 12 0.9 0.0 1.2 12 0.7

Soluble Reactive Phosphorus (mg/L)

Total Nitrogen (mg/L)

Stderr . 0.06 0.12 0.21 0.13

Min . 0.216 0.4425 0.378 0.196

Max . 1.06 1.8605 2.676 1.764

N Mean 160 1.5 12 1.7 12 1.9 16 2.2 12 3.0

. 0.7 0.6 .

. 0.07 0.05 .

. 0.34 0.296 .

. 1.604 1.282 .

12 28 28 7

0.7 1.5 0.9 1.9

0.08 0.13 0.06 0.53

0.3 0.6 0.5 0.6

1.4 3.7 1.8 4.7

. 23 .

. 0.6 .

. 0.09 .

. 0.286 .

. 2.541 .

137 23 10

0.4 0.7 0.4

0.01 0.04 0.00

0.3 0.0 0.4

. . .

. . .

. . .

. . .

. . .

7 21 11

0.7 1.1 1.4

0.08 0.10 0.17

0.4 0.2 0.6

37

Stderr 0.07 0.10 0.51 0.55 0.68

Min Max N 0.1 10.0 160 1.2 2.5 12 1.0 7.4 12 1.1 8.2 16 1.0 8.2 12

Total Phosphurus (mg/L)

Mean 0.6 0.5 0.6 0.3 0.6

Stderr 0.02 0.06 0.06 0.06 0.05

Min Max N Mean 0.1 1.3 160 0.77 0.2 1.0 12 0.81 0.3 1.1 12 0.92 0.1 0.8 16 0.43 0.4 1.0 12 1.03

12 28 28 7

0.2 0.6 0.3 0.3

0.02 0.05 0.01 0.07

0.1 0.2 0.2 0.1

0.4 1.1 0.5 0.5

12 28 28 7

0.9 1.0 0.4

137 23 8

0.1 0.1 0.0

0.00 0.01 0.01

0.0 0.1 0.0

0.2 0.2 0.1

0.9 1.8 2.2

. 24 12

. 0.3 0.4

. 0.04 0.08

. 0.1 0.1

. 0.7 1.0

Dissolved Silica (mg/L)

Stderr 0.03 0.11 0.12 0.10 0.12

Min 0.19 0.44 0.59 0.18 0.54

Max 1.50 1.96 2.08 1.43 2.09

N Mean . . 12 9.2 12 6.1 12 7.4 12 8.8

Stderr . 0.84 0.47 0.51 0.76

Min Max . . 0.6 11.7 4.1 9.2 3.7 9.1 3.3 12.0

0.28 0.71 0.34 0.48

0.03 0.05 0.02 0.11

0.16 0.29 0.18 0.24

0.49 . 1.32 24 0.57 24 0.98 .

. 7.0 5.0 .

. 0.71 0.62 .

. 2.0 1.2 .

. 15.1 11.3 .

137 23 8

0.14 0.19 0.07

0.01 0.01 0.01

0.02 0.37 10 0.01 0.30 23 0.04 0.10 .

3.1 3.9 .

0.66 0.23 .

0.2 2.7 .

7.0 6.5 .

6 24 12

0.24 0.39 0.48

0.04 0.04 0.13

0.13 0.36 . 0.13 0.88 24 0.12 1.67 12

. 6.9 7.7

. 0.79 1.51

. 0.1 2.5

. 14.0 19.9

Table 10:

Waters hed

Summary of biological water quality monitoring results in the Alafia River (AR), Little Manatee River (LMR), Feather Sound (FS), and Terra Ceia Bay (TCB) watersheds during 2006.

Tributary or Area

Uncorrected Chlorophyll-a (μg/L)

Mainstem Alafia River Dog Leg Creek Question Mark Creek Rice Creek Riverview Park West Creek

N Mean 160 27.9 12 56.8 12 83.5 16 94.4 12 119.1

LMR

Mainstem Little Manatee River Curiosity Creek Wildcat Creek Other Creeks draining to LMR

12 28 28 7

FS

Feather Sound/Old Tampa Bay Grassy Creek Other Creeks draining to FS Terra Ceia Bay Frog Creek McMullen Creek

AR

TCB

Fecal Coliform Bacteria (# col./100mL)

Corrected Chlorophyll-a (μg/L)

Stderr 4.02 13.66 42.89 50.67 44.90

Min 2.0 7.7 7.0 1.2 1.9

Max 315.3 147.9 546.5 650.8 529.5

N Mean 23 49.5 12 48.9 12 72.6 16 88.9 12 107.6

3.8 21.1 14.7 7.4

0.50 7.68 2.05 3.45

1.8 0.5 0.8 1.8

7.6 12 217.1 28 40.4 28 27.4 7

137 23 7

7.1 4.4 26.6

0.81 0.47 8.13

0.5 1.3 1.2

65.8 10.9 58.9

12 . .

5.9 . .

1.76 . .

1.2 . .

20.3 . .

Stderr 17.77 12.19 36.78 48.69 38.46

Min 1.8 6.1 7.1 0.7 1.5

Max 313.8 137.3 470.05 614.6 424.6

N Mean 23 222 12 505 12 57 16 701 12 415

3.5 18.8 12.8 3.7

0.66 7.62 1.91 0.81

0.9 0 0 0.7

8.6 215.1 35.5 6.3

12 28 28 7

82 321 309 414

49 55 54 110

20 600 12 20 1100 28 20 920 28 100 780 7

253 570 536 711

164 107 163 190

20 20 20 100

2000 2700 4000 1400

. 23 .

. 3.9 .

. 0.43 .

. 1.4 .

. 10.1 .

30 23 8

3 137 133

1 34 69

2 20 3

18 580 600

30 23 8

2 129 58

0 23 24

2 20 4

6 460 192

. 22 12

. 9.7 10.5

. 1.46 3.01

. 2 2.7

. 29.3 40.3

. 20 11

. 59 650

. 19 311

. 3 22

. . 310 17 3350 9

. 18 643

. 6 312

. 1 18

. 82 2500

38

Stderr 89 126 16 212 122

Min 10 20 20 20 20

Max 1700 1220 170 3500 1260

Enterococci Bacteria (# col./100mL) N Mean 23 288 12 398 12 113 16 999 12 322

Stderr 76 123 44 249 88

Min Max 10 1700 20 1200 20 560 60 3600 20 980

Table 11:

Tidal tributary benthic quality sampling information. EPCHC refers to the collections made by the Environmental Protection Commission of Hillsborough County, while MCEMD refers to collections made by the Manatee County Environmental Management Department.

Alafia River Tidal Tributary Season Sampling Date Dog Leg Creek Spring 10 May 2006 Dog Leg Creek Fall 27 Sept 2006 Question Mark Creek Spring 10 May 2006 Question Mark Creek Fall 27 Sept 2006 Rice Creek Spring 10 May 2006 Rice Creek Fall 27 Sept 2006 Riverview Park West Creek Spring 10 May 2006 Riverview Park West Creek Fall 27 Sept 2006 Mainstem Alafia River Spring 10 May 2006 Mainstem Alafia River Fall 14-17 Aug 2006 Little Manatee River Tidal Tributary Season Sampling Date Curiosity Creek Spring 08 May 2006 Curiosity Creek Fall 26 Sept 2006 Wild Cat Creek Spring 08 May 2006 Wild Cat Creek Fall 26 Sept 2006 Mainstem Little Manatee River Spring 08 May 2006 Mainstem Little Manatee River Fall 21-22 Aug 2006

Gear Petite Ponar Petite Ponar Petite Ponar Petite Ponar Petite Ponar Petite Ponar Petite Ponar Petite Ponar Petite Ponar Young Van Veen

Agency n EPCHC 1 EPCHC 1 EPCHC 1 EPCHC 2 EPCHC 2 EPCHC 2 EPCHC 2 EPCHC 1 EPCHC 6 EPCHC 12

Gear Petite Ponar Petite Ponar Petite Ponar Petite Ponar Petite Ponar Young Van Veen

Agency EPCHC EPCHC EPCHC EPCHC EPCHC EPCHC

N 3 3 3 3 6 6

Agency EPCHC EPCHC EPCHC EPCHC

n 6 6 6 8

Feather Sound / Old Tampa Bay Tidal Tributary Season Sampling Date Gear Grassy Creek Spring 11 May 2006 Petite Ponar Grassy Creek Fall 28 Sept 2006 Petite Ponar Feather Sound/Old Tampa Bay Spring 11 May 2006 Petite Ponar Feather Sound/Old Tampa Bay Fall 28 Aug 2006 Young Van Veen Terra Ceia Bay Tidal Tributary Season Sampling Date Gear Frog Creek Spring 23 May 2006 Petite Ponar Frog Creek Fall 28 Sept 2006 Petite Ponar McMullen Creek Spring 23 May 2006 Petite Ponar McMullen Creek Fall 28 Sept 2006 Petite Ponar Terra Ceia Bay Spring 24 May 2006 Petite Ponar Terra Ceia Bay Fall 21-22 Sept 2006 Young Van Veen

39

Agency N MCEMD 3 MCEMD 3 MCEMD 3 MCEMD 3 MCEMD 6 MCEMD 5

Table 12:

System

Mainstem Alafia River (Spring)

Summary statistics for bottom water quality and sediment composition for benthic sampling sites in the Alafia and Little Manatee River watersheds. ND = Not detected.

6

1

Dog Leg Creek (Fall)

1

Question Mark Creek (Spring)

1

Question Mark Creek (Fall)

2

Rice Creek (Spring)

2

Rice Creek (Fall)

2

Riverview Park Creek (Spring)

2

Riverview Park Creek (Fall)

System

Mainstem Little Manatee River (Spring) Mainstem Little Manatee River (Fall) Curiosity Creek (Spring)

Temperature (oC)

pH

Salinity (PSU)

D.O. (mg/L)

Silt/Clay (%)

Median Min Max 1

Median Min Max 27.76

Median Min Max 7.78

Median Min Max 8.84

Median Min Max 2.87

Median Min Mac 9.9

0.8

26.85

7.64

5.68

1.26

7.5

n

Mainstem Alafia 12 River (Fall) Dog Leg Creek (Spring)

Depth (meters)

1

2.3 1.8

1.1

25.87 3.3

1.2 1.2

1.2

0.6 0.6

1.1

6

3

Curiosity Creek (Fall)

3

Wildcat Creek (Spring)

3

Wildcat Mark Creek (Fall)

3

25.46

26.89

27.81

0.4

24.41

26.89

28.4

28.63

28.4

24.41

28.55

26.49

26.49

7.26

2.05

7.83

8.36

7.01

6.85

0.12

6.84 6.82

7.67

7.75

6.15

0.12

6.05

9

0.23

4.15

3.1

9.68

0.7

6.25

1.3

38.61

1.4

46.8

2.02

42.6

42.6


Median Min Max 7.62


Median Min Max 4.79

Median Min Mac 4.5

0.8

27.59

7.28

15.18

3.41

1.4

0.9

4.3 0.8

0.7

2.5

26.36

1.2

25.94

0.9

28.47

28.11

26.07

29.36

7.33

6.69

27.36

28.2

9.55

0.2

7.57

18.51

4.24

0.22

4.54

0.32

40

0.29

3.63

Benthic Chlorophyll-a (μg/L) Median Min Max . .

.

.

. 228.46

4.7

209.15

3.49

0

5.08

2.1

0

ND

5

51.48

601.72

38.61

1.5 1.4

19.31

102.97

3

4.09

572.76

19.31

0

4.07 0.4

17

1.4

4.67

21.22

.

.

2 4.47

3.17

22.2

1.4

3.35

20.73

6.92

4.36

2194.51

.

2.8

4.32

15.45

6.75

6.82 6.78

0.23

0.21

7.46 7.22

8.2

15.12 7.39

6.23 4.17

0.13

6.71

28.09 0.9

7.01 7.36

29.08

0.4 0.4

6.68

26.01

0.7 0.6

29.66

28.07

0.9 0.7

25.64

0.16

96.53 .

Median Min Max 1

6.87

.

42.6

Silt/Clay (%)

26.39

. 1145.52

D.O. (mg/L)

2.1

26.24

122.28 1103.69

40.1

Salinity (PSU)

21.57

ND

. 2.8

pH

7.92

ND

612.98

Temperature (oC)

29.79

ND 13.62

Depth (meters)

1.2

38.61 ND

61.4

33.3

473.01

38.61

2.1

4.73

2.02

27.4

1.1

2.02 0.23

473.01

14.8

18.5

3.92

8.81

17

40

6.15

0.23 7.03

14.8

7.92 7.4

. 473.01

14.8 2.55

0.18

8.91

7.03 7.03

12.28

0.12

7.71

27.4

2.17

7.21

.

27.4 0.15

2.55

. .

82.4

17

2.55

12.72

.

17 2.44

0.15

7.17

8.1

0.7

0.15 2.89

12.72

5.1

2.44

12.72 7.85

7.23

0.08

23.4 8.5

2.44 5.83

2.89

7.25

26.49 0.4

5.83

7.85 7.85

22.68

2.89 7.07

5.98 4.85

5.83 7.42

7.07

28.48 1.2

0.09

7.07

24.41

0.4 0.4

28.16

0.9

1.1 1

25.46

7.23

7.42

28.11

0.4 0.3

27.02

17.28 0.1

7.42

28.4

0.8 0.7

6.86

26.89

n

6

27.02

0.8 0.5

31.49

25.46 1.4

0.6

25.7

7.89 7.1

27.02

1.4 1.4

28.62

Benthic Chlorophyll-a (μg/L) Median Min Max .

2.1

ND

54.7

Table 13:

System

Feather Sound / Old Tampa Bay (Spring) Feather Sound / Old Tampa Bay (Fall) Grassy Creek (Spring) Grassy Creek (Fall)

System

Terra Ceia Bay (Spring) Terra Ceia Bay (Fall)

Summary statistics for bottom water quality and sediment composition for benthic sampling sites in the Feather Sound and Terra Ceia Bay watersheds. ND = Not detected. Temperature (oC)

pH

Salinity (PSU)

D.O. (mg/L)

Silt/Clay (%)

Median Min Max 1.1


Median Min Max 8.13


Median Min Max 5.56

Median Min Mac 8.3

0.7

27.58

7.94

24.96

4.63

3.5

n

6

8

3

3

1.3 4.4

0.8

5.5

6

5

3

Frog Creek (Fall)

3

McMullen Creek (Spring)

3

3

29.12

0.4 0.3

0.9

29.95

26.04

7.97

26.43

24.79

8.18

7.27

23.34

7.42

7

26.25

24.42

3.32

25.18

17.41

6.01

1.09

1.5

2.51

1.31

7.2

2.1

5

2.13

1.5

7.3

D.O. (mg/L)

Silt/Clay (%)

Median Min Max 1.2

Median Min Max 27

Median Min Max 7.9

Median Min Max 32

Median Min Max 4.7

Median Min Mac 17.1

0.7

27

3

27.15

0.4 0.2

0.6

27

0.1

26.7

0.2

8.15

0.5

27

28

7.3

27.4

7

26.5

8.21

21.8

7.3

7.5

19.5

7.7

0.5

6.9

26.7

5.53

23.5

31.2

5

3.7

5.4

41

4

7.82

1.5

5.6

2.6

8.3

1.5

2.55

10.2

6.8

.

6.6

.

2.7

23.1

264

4

134

6.5

847 196 300 641

4.5

618.5

920 192

9.8 7

. 286

4.4 5.3

. .

1.5

6.8

57.92


13.1

4.5 30.9

40.2

ND

3.8

5.9

6.7 7.35

2

5.2

28.6 7.5

5 6.69

0.6

7.2 27.8

4.1

29.6

7.3 27

32.7 22.9

7.2

26.6 0.1

32

7.3

27

0.1 0.1

29.32

26.8

0.5

7.9 8.21

27

0.1 0.1

7.4

28.26

257.42 1061.86 33.79

Salinity (PSU)

24

.

2.6

pH

2.4

. 667.69

Temperature (oC)

1

. .

Depth (meters)

0.6

.

3.3

1.57

17.82

11.6


2.1

1.21

17.55 7.1

6.14 5.16

24.84

7.07

25.37

25.4

25.65

7.32

24.97 0.5

8.15 8.15

26.1

0.3 0.2

27.92

29.87

n

Frog Creek (Spring)

McMullen Mark Creek (Fall)

Depth (meters)

13.7

160

307

Table 14:

Summary statistics for benthic community indices for benthic sampling sites in the Alafia and Little Manatee River watersheds. Number of Number per Diversity Evenness TBBI taxa m2 (H’) (J’) System n Median Median Median Median Median Min Max Min Max Min Max Min Max Min Max Mainstem 20 29004 1.96 0.68 81.73 6 Alafia River 3 31 860 87333 0.85 2.51 0.56 0.82 66.64 84.05 (Spring)

Mainstem Alafia River (Fall)

12

Dog Leg Creek (Spring)

1


1


1


2

Rice Creek (Spring)

2

Rice Creek (Fall)

2

Riverview Park Creek (Spring)

2

Riverview Park Creek (Fall)

1

System Mainstem Little Manatee River (Spring) Mainstem Little Manatee River (Fall)

n

6 6

Curiosity Creek (Spring)

3


3

Wildcat Creek (Spring)

3

Wildcat Creek (Fall)

3

9 1

4650 27

50

11 -

21700

-

0

23 18

15738

23

9589

15 13

28337

-

-

Number per m2 Median Min Max 25328

11

5848

19 21 19

100

8525

40936

3 25 21

31

172

258

18450

48807

2408 14

1763

1.83

1.20 0.56

1.87 2.37 1.68 1.56 2.21

7740

1.14

1.79

0.71 0.75

0.68

78.00

0.81

0.40 0.95 0.63

TBBI Median Min Max 86.04 78.59

87.14

63.17

72.74

82.01

89.11

60.26

63.97

86.49 0.69

0.78 0.48

-

60.96 0.97

0.50

-

86.99 0.52

0.81

80.19

70.06

0.43

1.26

42

-

0.26

90.84

80.89

Evenness (J’) Median Min Max 0.47

1.93 1.71

78.70

0.53

Diversity (H’) Median Min Max 1.32

82.56

79.10 0.65

-

83.03

84.77 0.77

0.63

1.04

27176

10 4

60931

78.51

0.64

-

0.56

0.00

80.54 0.75

0.32

1.25

172 5

0.53

0.54

41.52

0.55

2.77

-

-

0.65

2.17

76.77

-

-

2.11

58566 26

2

1.61

122637 0.78

4525 23

1.52

-

-

0.53

1.32

Number of taxa Median Min Max 19.5 21

-

1.72

5590 -

2

0.74

-

Undefined -

1.75

10965

26058

12 -

1.80

27198 17

-

71.37

73.26 -

1.98

38099

60.52

0.57 -

0.00

10277 36

-

0.76

24940

0.90

1.00 -

-

26919 28

10

12470

18

-

-

67.30

0.22

1.30

-

9 0

4730

-

0.47

1.10

-

10

1.99

-

129 -

0.61

0.54

-

3

-

0.00

10492 -

-

1.39

86.19

89.52

79.36 0.82

70.85

82.97

Table 15:

Alafia River tidal tributary benthic relative abundance.

Dog Leg Creek (Spring)


Taxa

%

Taxa

TUBIFICIDAE

89.34

Limnodrilus hoffmeisteri

4.51

Tanytarsus sp.

1.64

Mediomastus ambiseta; TUBIFICIDAE; Sinelobus stanfordi

Tanypus neopunctipennis

1.23

Procladius (Holotanypus) sp.

0.82

Grandidierella bonnieroides

33.33

Taxa Littoridinops palustris Stenoninereis martini TUBIFICIDAE Melanoides tuberculata; Mytilopsis leucophaeata; Tanypus clavatus ACTINARIA; Laeonereis culveri; Mediomastus ambiseta; Tubificoides wasselli

Riverview Park West Creek (Spring) Taxa TUBIFICIDAE; Littoridinops monroensis Laeonereis culveri Chironomus sp. Pyrgophorus platyrachis

%


%


%

Taxa

%

56.36

TUBIFICIDAE

50.69

22.73

Chironomus sp.

22.07

11.82

Littoridinops Palustris

10.69

1.82

Melanoides tuberculata

0.91

Mytilopsis leucophaeata

Riverview Park West Creek (Fall) Taxa

Rice Creek (Spring) Taxa Grandidierella bonnieroides Corbicula fluminea

Rice Creek (Fall) %

43.37

Taxa Corbicula fluminea

% 56.07

12.86

TUBIFICIDAE

8.58

TUBIFICIDAE

11.98

Pyrgophorus platyrachis

7.11

6.55

Tanytarsus sp.

9.27

Dubiraphia sp.

3.97

3.97

Polypedilum scalaneum group

5.03

Laeonereis culveri

3.77

Mainstem Alafia River (Spring)

Mainstem Alafia River (Fall)

%

Taxa

%

Taxa

%

23.00


54.62

Grandidierella bonnieroides

33.04


35.77

18.42 14.62 9.01

TUBIFICIDAE Polypedilum halterale group Procladius (Holotanypus) sp. Tanypus neopunctipennis; Dero nivea

28.46 6.15 3.08

Edotia triloba Mytilopsis leucophaeata Dicrotendipes sp.

10.29 8.22 5.79

Streblospio spp. Pyrgophorus platyrachis TUBIFICIDAE

17.11 12.17 7.88

1.54

Ampelisca abdita

5.62

Almyracuma proximoculi

6.20

5.93

43

Table 16:

Little Manatee River tidal tributary benthic relative abundance.

Curiosity Creek (Spring) Taxa Grandidierella bonnieroides Uromunna reynoldsi Apocorophium louisianum

Gammarus cf. tigrinus

Cyathura polita


%

Taxa

%

30.74

HYDROBIIDAE

28.57

24.31

TUBIFICIDAE; Cyathura polita

14.29

21.09

8.42

3.48

Amphiporus bioculatus; Corbicula fluminea; Cryptochironomus sp.; Polypedilum sp.: Polypedilum scalaneum group: Gammarus palustris

7.14

Wildcat Creek (Spring) Taxa Grandidierella bonnieroides

Wildcat Creek (Fall)

% 46.04

Taxa RISSOOIDEA sp. A of EPC

% 61.73

ACTINARIA

13.75

TUBIFICIDAE

10.11

RISSOOIDEA sp. A of EPC

6.42

Laeonereis culveri

7.22

Leptochelia sp.

4.92


4.78

Almyracuma proximoculi; Grandidierella bonnieroides

Apocorophium louisianum

44

Mainstem Little Manatee River (Spring) Taxa Apocorophium louisianum Grandidierella bonnieroides

% 65.11

Mainstem Little Manatee River (Fall) Taxa Grandidierella bonnieroides

% 29.68

17.98

TUBIFICIDAE

12.88

Cyathura polita

4.58

Polypedilum scalaneum group

10.41

4.33

Ampelisca abdita

1.75

Cyathura polita

9.95

3.25

ACTINARIA

1.23

Tubificoides motei

7.76

Table 17:

Summary statistics for benthic community indices for benthic sampling sites in the Feather Sound and Terra Ceia Bay watersheds.

System

n

Feather Sound / Old Tampa Bay (Spring)

6

Feather Sound / Old Tampa Bay (Fall)

8

Grassy Creek (Spring)

6

Grassy Creek (Fall)

6

System

n

Terra Ceia Bay (Spring)

6

Terra Ceia Bay (Fall)

5

Frog Creek (Spring)

3

Frog Creek (Fall)

3

McMullen Creek (Spring)

3

McMullen Creek (Fall)

3

Number of taxa Median Min Max

Number per m2 Median Min Max

Diversity (H’) Median Min Max

Evenness (J’) Median Min Max

TBBI Median Min Max

49

51042

2.70

0.70

77.50

22

57

9546

35 27

12689 68

3975

40 25

70251

83076 44

11825

23 17

80324

185373

12578 29

8643

15824

2.07

3.05

0.58

2.38 1.36

0.65 3.08

0.34

2.16 1.83

0.81

0.50

2.09

0.73

0.52

90.97

77.15

93.47

88.02

0.65 2.50

59.28

87.63

0.59 2.54

1.48

0.77

67.29

90.55

71.06 0.80

60.42

77.46

Number of taxa Median Min Max

Number per m2 Median Min Max

Diversity (H’) Median Min Max

Evenness (J’) Median Min Max

TBBI Median Min Max

31

12599

2.25

0.68

63.50

15

42

2193

29 21

4800 67

1100

15 15

8041

9 1290

15

5074 16426

24

1849

8 6

43817 1979

10

10

8426 15351

46

6

57706

71724 2021

10

430

2236

45

1.72

2.79

0.50

2.96 2.47

3.40

0.85 0.71

2.18 1.86

2.64

1.66

2.15

1.84

0.76

0.40

94.58

49.57

83.26

40.75

79.21

65.54 0.81

0.80 0.65

51.42

78.35

0.79

1.70 1.36

0.80

0.62

86.12

82.57

0.70

1.85 1.27

0.92

0.69

35.90

86.22

0.69

1.43 1.25

0.90

65.40

81.51

55.73 0.95

36.46

65.70

Table 18:

Feather Sound / Old Tampa Bay tidal tributary benthic relative abundance.

Grassy Creek (Spring) Taxa Leptochelia sp. Grandidierella bonnieroides Parastarte triquetra Fabricinuda trilobata Ampelisca abdita Table 19:


% 28.78 16.31 15.75 8.54 4.25

Taxa Laeonereis culveri TUBIFICIDAE Parastarte triquetra Stenoninereis martini Leitoscoloplos spp.

% 24.54 15.68 10.81 10.53 6.41

Taxa Axiothella mucosa Parastarte triquetra Tubificoides wasselli Ampelisca holmesi Fabricinuda trilobata

Feather Sound / Old Tampa Bay (Fall)

% 15.21 8.36 7.46 6.85 5.66

Taxa Exogone dispar Rudilemboides naglei Fabricinuda trilobata Mysella planulata Glottidia pyramidata

% 36.57 9.53 5.38 4.81 3.02

Terra Ceia Bay tidal tributary benthic relative abundance.

Frog Creek (Spring) Taxa Parastarte triquetra Laeonereis culveri Grandidierella bonnieroides Americorophium ellisi

Feather Sound / Old Tampa Bay (Spring)

Grassy Creek (Fall)

Frog Creek (Fall) %

20.86 14.20

Taxa Polypedilum halterale group Polypedilum scalaneum group

McMullen Creek (Spring) % 40.20

Taxa Grandidierella bonnieroides

McMullen Creek (Fall)

%

Taxa

%

58.29

TUBIFICIDAE

33.94

Streblospio spp. Laeonereis culveri

15.60

29.89

Leptochela sp.

7.88

Laeonereis culveri Parastarte triquetra

6.59 4.68

Chironomus sp.

7.34

Cyathura polita

4.63

Capitella capitata complex

4.59

10.62

Laeonereis culveri

7.22

6.14

Cryptochironomus sp.

4.12

4.73

HYDROBIIDAE

3.61

46

14.68

Terra Ceia Bay (Spring) Taxa Grandidierella bonnieroides Leptochelia sp. Exogone dispar Parastarte triquetra Fabricinuda trilobata

% 26.07

Terra Ceia Bay (Fall) Taxa Cymadusa compta

% 10.00

9.84

TUBIFICIDAE

8.92

7.15

Pileolaria rosepigmentata Xenanthura brevitelson

7.20

Tubificoides wasselli

4.52

6.70 6.51

4.73

Table 20:

Summary of watershed metrics for the tidal tributaries draining to the Alafia and Little Manatee Rivers, Feather Sound, and Terra Ceia Bay.

System Type

Minor Second Order Tributaries Discharging to a Major First Order Tributary

Minor First Order Tributaries Discharging Directly to Embayments

Watershed

Alafia River

Basin Size (ha)

Tributary

% Impervious Cover (USGS 2001) Basin (%)

100-m Stream Corridor (%)

Landscape Development Intensity Indices (SWFWMD 2004) 100-m Stream Basin Corridor (Indices) (Indices)

Dog Leg Creek

35.5

2.55

2.13

6.04

3.05

Question Mark Creek

23.2

7.04

2.35

5.68

3.96

1315.4

9.81

6.9

4.91

3.72

68.2

16.57

6.93

6.22

6.43

Rice Creek Riverview Park West Creek

Little Manatee River

Curiosity Creek

5725.9

0.9

0.58

3.19

3.01

Wildcat Creek

926.3

1.89

0.83

3.2

2.48

Feather Sound

Grassy Creek

159.9

4.24

1.18

1.62

1.08

Frog Creek

2357.2

6.65

3.12

4.11

3.31

McMullen Creek

757.5

13.89

9.12

5.16

4.79

Terra Ceia Bay

47

6.

FIGURES

48

Figure 1:

Overview map showing the location of the select tidal tributary study areas. The tributaries draining to Feather Sound and Terra Ceia Bay were considered first order tributaries. The tributaries draining to the Alafia and Little Manatee Rivers were considered second order tributaries. Tributaries in the Alafia River and Feather Sound watersheds were considered a priori more disturbed.

49

90 2006 Total Annual Rainfall

Total Annual Rainfall (in.)

80

70

60

50

40

30 55

Alafia River


Coastal Tampa Bay

Terra Ceia Bay


Coastal Tampa Bay

Terra Ceia Bay


Coastal Tampa Bay

Terra Ceia Bay

2006 Wet Season Rainfall

Wet Season Rainfall (in.)

50 45 40 35 30 25 20 15 Alafia River 50

Dry Season Rainfall (in.)

2006 Dry Season Rainfall 40

30

20

10

0 Alafia River

Figure 2:

Total annual, wet season, and dry season rainfall conditions in the tidal tributary watersheds over the period of record (1915-2006) and during 2006 (Adapted from SWFWMD 2007).

50

Figure 3:

Aerial maps showing sample sites in the Alafia (top, a priori disturbed) and Little Manatee (bottom, a priori less disturbed) Rivers. Water quality (yellow circle) and benthic quality (red triangle) sites monitored in 2006 for the tidal tributary study are depicted. Also depicted are additional monitoring sites adjacent to the tributary study areas.

51

Figure 4:

Aerial maps showing sample sites in Feather Sound (top, a priori disturbed) and Terra Ceia Bay (bottom, a priori less disturbed). Water quality (yellow circle) and benthic quality (red triangle) sites monitored in 2006 for the tidal tributary study are depicted. Also depicted are additional monitoring sites adjacent to the tributary study areas.

52

Le g

Bottom Temperature (oC) 25

20

15

10

5

Figure 6: Bottom Temperature (oC)

Figure 5:

Cu rio sit yC re ek -S Cu pr rio ing sit yC re ek W ild -F ca all tC re ek -S W pr ild ing ca tC Lit tle re ek M an -F at all ee Ri ve Lit r tle -S M pr an ing at ee Ri ve rFa ll

Cr ee Do k Q g -S ue Le st pr g ion in Cr M ee g ar Q k k ue -F Cr st al ee io l n k M S ar pr k in Cr g Ri ee ce Ri Cr k - F ve ee al rv l k ie -S w Ri Pa ce pr in Ri r C k g ve re W rv ek es ie -F tC w Pa al re l ek rk W -S es p r tC in Al g af ree ia k -F Ri ve a r - ll Al Sp af rin ia g Ri ve rFa ll

Do g Le g

Cu rio sit yC re ek -S Cu pr rio ing sit yC re ek W ild -F ca all tC re ek -S W pr ing ild ca tC Lit tle re ek M an -F at all ee Ri ve Lit rtle Sp M rin an g at ee Ri ve rFa ll

Cr ee Do k Q g -S ue L eg st pr io in Cr n g M ee ar Q k k ue -F C st al re io l ek n M -S ar p k rin C g Ri re ce e Ri Cr k - F ve e a ek rv ll ie -S w Ri Pa ce pr i Ri n r C k g ve re W rv ek es ie -F tC w Pa al re l ek rk W -S es p r tC in Al g af ree ia k -F Ri ve a r - ll Al Sp af rin ia Ri g ve rFa ll

Do g

Depth (meters) 1.5

1.0

Depth (meters)

Tidal Streams Study 2006 Alafia River Area

Tidal Streams Study 2006 Little Manatee River Area

3.0

4

2.5

2.0

3

0

53

2

0.5

1

0.0

0

Alafia River and Little Manatee River tidal tributary benthic sample depths.



35

31

30

30

29

28

27

26

25

24

23

22

21

20

Alafia River and Little Manatee River tidal tributary benthic sampling bottom temperatures.

Le g

Bottom Salinity (PSU) 15

10

5

Figure 8: Bottom Salinity (PSU)

Figure 7:


Cr ee Do k Q g -S ue Le st pr g io in Cr n g M ee a Q k rk ue Cr Fa st ee io ll n k M -S ar pr k in Cr g Ri ee ce Ri Cr k - F ve ee al rv l k ie -S w Ri Pa ce pr in Ri r C k g ve re W rv ek es ie -F tC w Pa al re l ek rk W -S es t C prin Al g af ree ia k -F Ri ve a r - ll Al Sp af rin ia g Ri ve rFa ll

Do g

Le g

Cu rio sit yC re ek -S Cu pr rio ing sit yC re ek W ild -F ca all tC re ek -S W pr ild ing ca tC Lit tle re ek M an -F at all ee Ri ve Lit rtle Sp M an rin at g ee Ri ve rFa ll

Cr ee Do k Q g -S ue Le st pr g io in C n g re M ek ar Q k ue Cr Fa st ee io ll n k M -S ar pr k i ng Cr Ri ee ce Ri Cr k - F ve ee al rv l k ie -S w Ri Pa ce pr i Ri ng rk Cr ve W ee rv es k ie -F tC w Pa al re l ek rk W -S es p rin tC Al g af ree ia k Ri ve Fa r - ll Al Sp af rin ia g Ri ve rFa ll

Do g

7.0

pH

pH



8.5

8.0

8.0

7.5

7.5

6.5

54

7.0

6.5

6.0

6.0

Alafia River and Little Manatee River tidal tributary benthic sampling bottom pH.



25

25

20

20

15

10

5

0

0

Alafia River and Little Manatee River tidal tributary benthic sampling bottom salinity.

Le g

% Silt + Clay 60

40

Figure 10: % Silt + Clay

Figure 9:


C Do reek Q g -S ue L eg st pr io in Cr n M ee g ar Q k k ue Cr Fa st ee io ll n k M -S ar p k r i n C g Ri ce reek Ri Cr -F ve e al rv ek l ie -S w Ri ce Pa pr i Ri n r Cr k ve W ee g rv es k ie -F tC w Pa al re l ek rk W -S es p rin t Al Cr g e af ia ek -F Ri ve al l rAl Sp af rin ia Ri g ve rFa ll

Do g


Le g C Do reek Q g -S ue L eg st p ion Cr ring M ee ar Q k k ue -F Cr st al ee ion l k M Sp ar k r i n g Ri Cre ce e Ri Cr k ve F e al rv ek iew -S l Ri ce Pa pr Ri i ng r C k ve re W rv ek es ie -F tC w Pa al re l e rk W k-S es pr t in Al Cr g af e ia ek Ri -F ve r - all Al Sp af rin ia Ri g ve rFa ll

Do g

Bottom Dissolved Oxygen (mg/L) 9

8

7

6

5

4

3

2

1




12

11

7

10

100

20

55

6

5

4

3

2

0

1

0

Alafia River and Little Manatee River tidal tributary benthic sampling bottom dissolved oxygen.



20

80

15

10

5

0

0

Alafia River and Little Manatee River tidal tributary benthic sampling sediment composition (% silt + clay).

Tidal Streams Study 2006 Alafia River Area 100

Cadmium (mg/kg)

Alafia River Baseline - Black Dog Leg Creek - Pink Question Mark Creek - Blue Rice Creek - Green Riverview Park West - Red 10

1

0.1 100

1000

10000

100000

Aluminum (mg/kg)

Figure 11:

Alafia River area tidal tributary Cd: Al regression with 95% prediction intervals. Dash lines represent TEL (lower) and PEL (upper) for Cd.

Tidal Streams Study 2006 Alafia River Area 1000

Selenium (mg/kg)

Alafia River Baseline - Black Dog Leg Creek - Pink Question Mark Creek - Blue Rice Creek - Green Riverview Park West - Red 100

10

1 100

1000

10000

100000

Aluminum (mg/kg)

Figure 12:

Alafia River area tidal tributary Se:Al regression with 95% prediction intervals.

56


Arsenic (mg/kg)

100

10

1 Alafia River Baseline - Black Dog Leg Creek - Pink Question Mark Creek - Blue Rice Creek - Green Riverview Park West - Red 0.1 100

1000

10000

100000

Aluminum (mg/kg)

Figure 13:

Alafia River area tidal tributary As: Al regression with 95% prediction intervals. Dash lines represent TEL (lower) and PEL (upper) for As.

Tidal Streams Study 2006 Little Manatee River Area 100

Cadmium (mg/kg)

10

Fall

1

Spring

0.1 Curiosity Creek - Red Wildcat Creek - Green Little Manatee River Baseline - Black 0.01 100

1000

10000

100000

Aluminum (mg/kg)

Figure 14:

Little Manatee River area tidal tributary Cd:Al regression with 95% prediction intervals. Dash lines represent TEL (lower) and PEL (upper) for Cd.

57

Tidal Streams Study 2006 Old Tampa Bay/Feather Sound Area

Tidal Streams Study 2006 Terra Ceia Bay Area

6

2.5

2.0

4

Depth (meters)

Depth (meters)

5

3

2

1.5

1.0

0.5

1

-F al l

Te rra

Ce ia

Ba y

-S pr in g

-F al l Te rra

Ce ia

Ba y

Cr ee k

-S pr in g

M cM ul le n

Feather Sound/Old Tampa Bay and Terra Ceia Bay tidal tributary benthic sampling depths.


Tidal Streams Study 2006 Old Tampa Bay/Feather Sound Area 30

35 34

29

33

28

Bottom Temperature (oC)

32

Bottom Temperature (oC)

Cr ee k

M cM ul le n

Fr og

Cr ee k Fr og

O ld

O ld

Cr ee k

-S pr in g

-F al l Ta m pa

Ba y Ta m pa

G ra ss y

Ba y

-S pr in g

-F al l Cr ee k

-S pr in g Cr ee k G ra ss y

Figure 15:

-F al l

0.0

0

31 30 29 28 27 26 25 24

27 26 25 24 23 22

23 22

21

21 -F al l Ba y

Ce ia Te rra

Te rra

Ce ia

Ba y

-S pr in g

-F al l Cr ee k

-S pr in g

M cM ul le n

Cr ee k

M cM ul le n

Cr ee k

Cr ee k Fr og

Fr og

-S pr in g

-F al l Ba y Ta m pa

O ld

O ld

Ta m pa

Ba y

-S pr in g

-F al l Cr ee k G ra ss y


Figure 16:

-F al l

20

20

Feather Sound/Old Tampa Bay and Terra Ceia Bay tidal tributary benthic bottom temperature.

58


Tidal Streams Study 2006 Old Tampa Bay/Feather Sound Area 8.5

8.5

8.0

8.0

7.5

pH

pH

7.5

7.0

7.0

6.5

6.5

O ld

Fa ll Ba y-

Ce ia Te rra

Ce ia

Ba y

-S pr in g

-F al l Cr ee k Te rra

-S pr in g

M cM ul le n

Cr ee k

Cr ee k

M cM ul le n

-S pr in g

O ld

Fr og

Fr og

Cr ee k

Fa ll Ta m pa

Ba yTa m pa

G ra ss y

Ba y-

Sp rin g

-F al l Cr ee k


Figure 17:

-F al l

6.0

6.0

Feather Sound/Old Tampa Bay and Terra Ceia Bay tidal tributary benthic bottom pH.



30

30

Bottom Salinity (PSU)

20

15

10

25

20

15

10

5

5

Feather Sound/Old Tampa Bay and Terra Ceia Bay tidal tributary benthic bottom salinity.

59

-F al l Ba y

Ce ia

Te rra

Te rra

Ce ia

Ba y-

Sp rin g

-F al l Cr ee k

-S pr in g

M cM ul le n

Cr ee k

Cr ee k

Cr ee k Fr og

Fr og

-S pr in g

Fa ll Ba yTa m pa

O ld

O ld

Ta m pa

Ba y

-S pr in g



Figure 18:

-F al l

0

0

M cM ul le n

Bottom Salinity (PSU)

25



7


5

4

3

2

1

7 6 5 4 3 2 1

-F al l Ba y

Ce ia Te rra

Ce ia

Ba y

-S pr in g


-S pr in g

Feather Sound/Old Tampa Bay and Terra Ceia Bay tidal tributary benthic bottom dissolved oxygen.



14

30

12

25

% Silt + Clay

10

8

6

20

15

10

4

5

2

-F al l Ba y

Ce ia

Te rra

Ce ia

Ba y-

Sp rin g


-S pr in g

M cM ul le n

Cr ee k

Cr ee k

Cr ee k Fr og

Fr og

-S pr in g

-F al l Ta m pa

O ld

Ba y Ta m pa O ld

Ba y

-S pr in g



Figure 20:

-F al l

0

0

M cM ul le n

% Silt + Clay

M cM ul le n

M cM ul le n

Fr og

Cr ee k

Cr ee k

Cr ee k

-S pr in g

-F al l Ta m pa

O ld

O ld

Ta m pa

G ra ss y

Ba y

Ba y

-S pr in g

-F al l Cr ee k


Figure 19:

-F al l

0

0

Fr og


8

6

Feather Sound/Old Tampa Bay and Terra Ceia Bay tidal tributary benthic sediment composition (% silt+clay).

60


Cadmium (mg/kg)

10

1

Fall Spring

0.1 Grassy Creek - Red Old Tampa Bay - Black 0.01 1

10

100

1000

10000

100000

Aluminum (mg/kg)

Figure 21:

Grassy Creek and Feather Sound/Old Tampa Bay Cd:Al regression with 95% prediction intervals. Dash lines represent TEL (lower) and PEL (upper) for Cd.

61

Benthic Abundance (#/m2) 1000

100

Figure 23: Benthic Abundance (#/m2)

Figure 22:

Cu rio sit yC re ek -S Cu pr rio ing sit yC re ek W ild -F ca all tC re ek -S W pr ild ing ca tC Lit tle re ek Ma -F na all te eR i v Lit er tle -S Ma pr ing na tee Ri ve rFa ll

Le g C Do reek Qu g Le - Sp es tio g Cr ring n M ee ar Qu k k -F es all tio Cre ek n M S ar k C prin Ri g ce ree Ri Cr k ve ee Fa rv ll k iew Ri ce Spr Pa Ri ing Cr ve rk W ee rv kiew est Fa Pa Cre ll ek rk W -S es p Al t Cr ring af ee ia Ri k - F ve r - all Al Sp af ia r Ri ing ve rFa ll

Do g

Le g


Cr ee Do k Q g -S ue Le st pr g io in Cr n M ee g a Q k rk ue Cr Fa st ee ion ll k M -S ar pr k ing Cr Ri ce eek Ri Cr -F ve ee al rv l k iew -S Ri Pa ce pr in Ri r C k g ve re W rv ek es ie -F t w Pa Cre all ek rk W -S es t C prin Al g af ree ia k -F Ri ve a r - ll Al Sp af rin ia g Ri ve rFa ll

Do g

Number of Taxa 30

20

Number of Taxa



50

35

40

30

25

10

62

20

15

10

0

5

0

Alafia River and Little Manatee River tidal tributary benthic species richness. Tidal Streams Study 2006 Alafia River Area


100000

1000000

10000

100000

10000

1000

100

10

10

1

Alafia River and Little Manatee River tidal tributary benthic abundance.

Tampa Bay Benthic Index 60

40

20

Figure 25: Tampa Bay Benthic Index

Figure 24:


Le g C Do reek Q g -S ue L eg st p ion Cr ring M ee ar Q k k ue -F Cr st all ee io n k M Sp ar k rin C g Ri ce reek Ri C ve re Fa rv ek ll iew -S Ri ce Pa pr i Ri n r Cr k ve W ee g rv es k ie -F tC w Pa al re l ek rk W -S es p rin t Al Cr g e af ia ek -F Ri ve al l rAl Sp af rin ia Ri g ve rFa ll

Do g Le g


C Do reek Qu g -S Le es pr tio g in Cr n g M ee ar Qu k k -F es Cr al tio ee l n k M -S ar p k rin C g Ri r ce eek Ri Cr -F ve e a rv ek ll ie -S w Ri Pa ce pr i Ri n r C k g ve re W rv ek es ie -F tC w Pa all re ek rk W -S es pr t in Al Cr g ee af ia k -F Ri ve a r - ll Al Sp af rin ia Ri g ve rFa ll

Do g

Shannon Diversity Index (H') 2.5

2.0

1.5

1.0

0.5

Shannon Diversity Index (H')



3.5

3.0

3.0

2.5

63

2.0

1.5

1.0

0.0

0.5

0.0

Alafia River and Little Manatee River tidal tributary benthic diversity. Tidal Streams Study 2006 Alafia River Area


100

100

80

80

60

40

20

0

0

Alafia River and Little Manatee River tidal tributary: Tampa Bay Benthic Index. Dash lines indicate cutoffs for Healthy (>87) and Degraded (87) and Degraded (