Funding & Acknowledgements

The data used in this analysis is from the Export Standardized Tables in the SEACAR Data Discovery Interface (DDI). Documents and information available through the SEACAR DDI are owned by the data provider(s) and users are expected to provide appropriate credit following accepted citation formats. Users are encouraged to access data to maximize utilization of gained knowledge, reducing redundant research and facilitating partnerships and scientific innovation.

With respect to documents and information available from SEACAR DDI, neither the State of Florida nor the Florida Department of Environmental Protection makes any warranty, expressed or implied, including the warranties of merchantability and fitness for a particular purpose arising out of the use or inability to use the data, or assumes any legal liability or responsibility for the accuracy, completeness, or usefulness of any information, apparatus, product, or process disclosed, or represents that its use would not infringe privately owned rights.

This report was funded in part, through a grant agreement from the Florida Department of Environmental Protection, Florida Coastal Management Program, by a grant provided by the Office for Coastal Management under the Coastal Zone Management Act of 1972, as amended, National Oceanic and Atmospheric Administration. The views, statements, findings, conclusions and recommendations expressed herein are those of the author(s) and do not necessarily reflect the views of the State of Florida, NOAA or any of their sub agencies.

Published: 2025-10-08

Threshold Filtering

Threshold filters, following the guidance of Florida Department of Environmental Protection’s (FDEP) Division of Environmental Assessment and Restoration (DEAR) are used to exclude specific results values from the SEACAR Analysis. Based on the threshold filters, Quality Assurance / Quality Control (QAQC) Flags are inserted into the SEACAR_QAQCFlagCode and SEACAR_QAQC_Description columns of the export data. The Include column indicates whether the QAQC Flag will also indicate that data are excluded from analysis. No data are excluded from the data export, but the analysis scripts can use the Include column to exclude data (1 to include, 0 to exclude).

Continuous Water Quality threshold values
Parameter Name Units Low Threshold High Threshold
Dissolved Oxygen mg/L -0.000001 50
Dissolved Oxygen Saturation % -0.000001 500
Salinity ppt -0.000001 70
Turbidity NTU -0.000001 4000
Water Temperature Degrees C -5.000000 45
pH None 2.000000 14
Discrete Water Quality threshold values
Parameter Name Units Low Threshold High Threshold
Ammonia, Un-ionized (NH3) mg/L - -
Ammonium, Filtered (NH4) mg/L - -
Chlorophyll a, Corrected for Pheophytin ug/L - -
Chlorophyll a, Uncorrected for Pheophytin ug/L - -
Colored Dissolved Organic Matter PCU - -
Dissolved Oxygen mg/L -0.000001 25
Dissolved Oxygen Saturation % -0.000001 310
Fluorescent Dissolved Organic Matter QSE - -
Light Extinction Coefficient m^-1 - -
NO2+3, Filtered mg/L - -
Nitrate (NO3) mg/L - -
Nitrite (NO2) mg/L - -
Nitrogen, organic mg/L - -
Phosphate, Filtered (PO4) mg/L - -
Salinity ppt -0.000001 70
Secchi Depth m 0.000001 50
Specific Conductivity mS/cm 0.005000 100
Total Kjeldahl Nitrogen mg/L - -
Total Nitrogen mg/L - -
Total Nitrogen mg/L - -
Total Phosphorus mg/L - -
Total Suspended Solids mg/L - -
Turbidity NTU - -
Water Temperature Degrees C 3.000000 40
pH None 2.000000 13
Quality Assurance Flags inserted based on threshold checks listed in Table 1 and 2
SEACAR QAQC Description Include SEACAR QAQCFlagCode
Exceeds maximum threshold 0 2Q
Below minimum threshold 0 4Q
Within threshold tolerance 1 6Q
No defined thresholds for this parameter 1 7Q

Value Qualifiers

Value qualifier codes included within the data are used to exclude certain results from the analysis. The data are retained in the data export files, but the analysis uses the Include column to filter the results.

STORET and WIN value qualifier codes

Value qualifier codes from STORET and WIN data are examined with the database and used to populate the Include column in data exports.

Value Qualifier codes excluded from analysis
Qualifier Source Value Qualifier Include MDL Description
STORET-WIN H 0 0 Value based on field kit determination; results may not be accurate
STORET-WIN J 0 0 Estimated value
STORET-WIN V 0 0 Analyte was detected at or above method detection limit
STORET-WIN Y 0 0 Lab analysis from an improperly preserved sample; data may be inaccurate

Discrete Water Quality Value Qualifiers

The following value qualifiers are highlighted in the Discrete Water Quality section of this report. An exception is made for Program 476 - Charlotte Harbor Estuaries Volunteer Water Quality Monitoring Network and data flagged with Value Qualifier H are included for this program only.

H - Value based on field kit determiniation; results may not be accurate. This code shall be used if a field screening test (e.g., field gas chromatograph data, immunoassay, or vendor-supplied field kit) was used to generate the value and the field kit or method has not been recognized by the Department as equivalent to laboratory methods.

I - The reported value is greater than or equal to the laboratory method detection limit but less than the laboratory practical quantitation limit.

Q - Sample held beyond the accepted holding time. This code shall be used if the value is derived from a sample that was prepared or analyzed after the approved holding time restrictions for sample preparation or analysis.

S - Secchi disk visible to bottom of waterbody. The value reported is the depth of the waterbody at the location of the Secchi disk measurement.

U - Indicates that the compound was analyzed for but not detected. This symbol shall be used to indicate that the specified component was not detected. The value associated with the qualifier shall be the laboratory method detection limit. Unless requested by the client, less than the method detection limit values shall not be reported

Systemwide Monitoring Program (SWMP) value qualifier codes

Value qualifier codes from the SWMP continuous program are examined with the database and used to populate the Include column in data exports. SWMP Qualifier Codes are indicated by QualifierSource=SWMP.

SWMP Value Qualifier codes
Qualifier Source Value Qualifier Include Description
SWMP -1 1 Optional parameter not collected
SWMP -2 0 Missing data
SWMP -3 0 Data rejected due to QA/QC
SWMP -4 0 Outside low sensor range
SWMP -5 0 Outside high sensor range
SWMP 0 1 Passed initial QA/QC checks
SWMP 1 0 Suspect data
SWMP 2 1 Reserved for future use
SWMP 3 1 Calculated data: non-vented depth/level sensorcorrection for changes in barometric pressure
SWMP 4 1 Historical: Pre-auto QA/QC
SWMP 5 1 Corrected data

Water Column

The water column habitat extends from the water’s surface to the bottom sediments, and it’s where fish, dolphins, crabs and people swim! So much life makes its home in the water column that the health of marine and coastal ecosystems, as well as human economies, depend on the condition of this vulnerable habitat. Local patterns of rainfall, temperature, winds and currents can rapidly change the condition of the water column, while global influences such as El Niño/La Niña, large-scale fluctuation in sea temperatures and climate change can have long-term effects. Inputs from the prosperity of our day-to-day lives including farming, mining and forestry, and emissions from power generation, automobiles and water treatment can also alter the health of the water column. Acting alone or together, each input can have complex and lasting effects on habitats and ecosystems.


SEACAR evaluates water column health with several essential parameters. These include nutrient surveys of nitrogen and phosphorus, and water quality assessments of salinity, dissolved oxygen, pH, and water temperature. Water clarity is evaluated with Secchi depth, turbidity, levels of chlorophyll a, total suspended solids, and colored dissolved organic matter. Additionally, the richness of nekton is indicated by the abundance of free-swimming fishes and macroinvertebrates like crabs and shrimps.

Seasonal Kendall-Tau Analysis

Indicators must have a minimum of five to ten years, depending on the habitat, of data within the geographic range of the analysis to be included in the analysis. Ten years of data are required for discrete parameters, and five years of data are required for continuous parameters. If there are insufficient years of data, the number of years of data available will be noted and labeled as “insufficient data to conduct analysis”. Further, for the preferred Seasonal Kendall-Tau test, there must be data from at least two months in common across at least two consecutive years within the RCP managed area being analyzed. Values that pass both of these tests will be included in the analysis and be labeled as Use_In_Analysis = TRUE. Any that fail either test will be excluded from the analyses and labeled as Use_In_Analysis = FALSE. The points for all Water Column plots displayed in this section are monthly averages. Trend significance will be denoted as “Significant Trend” (when p < 0.05), or “Non-significant Trend” (when p >= 0.05). Any parameters with insufficient data to perform Seasonal Kendall-Tau test will have their monthly averages plotted without a corresponding trend line.

Water Quality - Discrete

The following files were used in the discrete analysis:

  • Combined_WQ_WC_NUT_Chlorophyll_a_corrected_for_pheophytin-2025-Sep-04.txt

  • Combined_WQ_WC_NUT_Chlorophyll_a_uncorrected_for_pheophytin-2025-Sep-04.txt

  • Combined_WQ_WC_NUT_Colored_dissolved_organic_matter_CDOM-2025-Sep-04.txt

  • Combined_WQ_WC_NUT_Dissolved_Oxygen-2025-Sep-04.txt

  • Combined_WQ_WC_NUT_Dissolved_Oxygen_Saturation-2025-Sep-04.txt

  • Combined_WQ_WC_NUT_pH-2025-Sep-04.txt

  • Combined_WQ_WC_NUT_Salinity-2025-Sep-04.txt

  • Combined_WQ_WC_NUT_Secchi_Depth-2025-Sep-04.txt

  • Combined_WQ_WC_NUT_Total_Nitrogen-2025-Sep-04.txt

  • Combined_WQ_WC_NUT_Total_Phosphorus-2025-Sep-04.txt

  • Combined_WQ_WC_NUT_Total_Suspended_Solids_TSS-2025-Sep-04.txt

  • Combined_WQ_WC_NUT_Turbidity-2025-Sep-04.txt

  • Combined_WQ_WC_NUT_Water_Temperature-2025-Sep-04.txt

Chlorophyll a, Corrected for Pheophytin - Discrete

Seasonal Kendall-Tau Trend Analysis

Scatter plot of monthly average levels of chlorophyll a, corrected for pheophytin, over time. If the time series included ten or more years of discrete observations, a significant (blue) or non-significant (magenta) trend line is also shown. Only laboratory-analyzed chlorophyll a (triangles) is included in the plot.
Scatter plot of monthly average levels of chlorophyll a, corrected for pheophytin, over time. If the time series included ten or more years of discrete observations, a significant (blue) or non-significant (magenta) trend line is also shown. Only laboratory-analyzed chlorophyll a (triangles) is included in the plot.
Seasonal Kendall-Tau Trend Analysis for Chlorophyll a, Corrected for Pheophytin
Activity Type Statistical Trend Sample Count Years with Data Period of Record Median tau Sen Intercept Sen Slope p
Lab Significantly decreasing trend 711 11 2010 - 2025 4.6 -0.3434 8.8752 -0.4458 0.0021

Monthly average chlorophyll a, corrected for pheophytin, decreased by 0.45 µg/L per year, indicating an increase in water clarity.

Map showing location of discrete water quality sampling locations within the boundaries of Boca Ciega Bay Aquatic Preserve. The bubble size on the maps above reflect the amount of data available at each sampling site.
Map showing location of discrete water quality sampling locations within the boundaries of Boca Ciega Bay Aquatic Preserve. The bubble size on the maps above reflect the amount of data available at each sampling site.
Programs contributing data for Chlorophyll a, Corrected for Pheophytin
ProgramID N_Data YearMin YearMax
5002 726 2010 2025

Program names:

5002 - Florida STORET / WIN1

Chlorophyll a, Uncorrected for Pheophytin - Discrete

Seasonal Kendall-Tau Trend Analysis

Scatter plot of monthly average levels of chlorophyll a, uncorrected for pheophytin, over time. If the time series included ten or more years of discrete observations, a significant (blue) or non-significant (magenta) trend line is also shown. Only laboratory-analyzed chlorophyll a (triangles) is included in the plot.
Scatter plot of monthly average levels of chlorophyll a, uncorrected for pheophytin, over time. If the time series included ten or more years of discrete observations, a significant (blue) or non-significant (magenta) trend line is also shown. Only laboratory-analyzed chlorophyll a (triangles) is included in the plot.
Seasonal Kendall-Tau Trend Analysis for Chlorophyll a, Uncorrected for Pheophytin
Activity Type Statistical Trend Sample Count Years with Data Period of Record Median tau Sen Intercept Sen Slope p
Lab Significantly decreasing trend 681 15 2000 - 2025 5.4 -0.4047 12.3253 -0.3263 0.0002

Monthly average chlorophyll a, uncorrected for pheophytin, decreased by 0.33 µg/L per year, indicating an increase in water clarity.

Map showing location of discrete water quality sampling locations within the boundaries of Boca Ciega Bay Aquatic Preserve. The bubble size on the maps above reflect the amount of data available at each sampling site.
Map showing location of discrete water quality sampling locations within the boundaries of Boca Ciega Bay Aquatic Preserve. The bubble size on the maps above reflect the amount of data available at each sampling site.
Programs contributing data for Chlorophyll a, Uncorrected for Pheophytin
ProgramID N_Data YearMin YearMax
5002 668 2010 2025
95 8 2004 2018
103 7 2000 2015
115 5 2000 2003
118 3 2000 2010

Program names:

95 - Harmful Algal Bloom Marine Observation Network2
103 - EPA STOrage and RETrieval Data Warehouse (STORET)/WQX3
115 - Environmental Monitoring Assessment Program4
118 - National Aquatic Resource Surveys, National Coastal Condition Assessment5
5002 - Florida STORET / WIN1

Dissolved Oxygen - Discrete

Seasonal Kendall-Tau Trend Analysis

Scatter plot of monthly average dissolved oxygen over time. If the time series included ten or more years of discrete observations, a significant (blue) or non-significant (magenta) trend line is also shown. Only dissolved oxygen values measured in the field (circles) are included in the plot.
Scatter plot of monthly average dissolved oxygen over time. If the time series included ten or more years of discrete observations, a significant (blue) or non-significant (magenta) trend line is also shown. Only dissolved oxygen values measured in the field (circles) are included in the plot.
Seasonal Kendall-Tau Trend Analysis for Dissolved Oxygen
Activity Type Statistical Trend Sample Count Years with Data Period of Record Median tau Sen Intercept Sen Slope p
Field No significant trend 30556 39 1974 - 2025 6.44 0.0503 6.4914 0.0048 0.179

Dissolved oxygen showed no detectable trend between 1974 and 2025.

Map showing location of discrete water quality sampling locations within the boundaries of Boca Ciega Bay Aquatic Preserve. The bubble size on the maps above reflect the amount of data available at each sampling site.
Map showing location of discrete water quality sampling locations within the boundaries of Boca Ciega Bay Aquatic Preserve. The bubble size on the maps above reflect the amount of data available at each sampling site.
Programs contributing data for Dissolved Oxygen
ProgramID N_Data YearMin YearMax
5002 13990 1995 2025
69 10788 1989 2024
4067 5571 1995 2023
95 228 1974 2018
115 10 2000 2003
118 8 2000 2015
103 6 2015 2015

Program names:

69 - Fisheries-Independent Monitoring (FIM) Program6
95 - Harmful Algal Bloom Marine Observation Network2
103 - EPA STOrage and RETrieval Data Warehouse (STORET)/WQX3
115 - Environmental Monitoring Assessment Program4
118 - National Aquatic Resource Surveys, National Coastal Condition Assessment5
4067 - Tampa Bay Benthic Monitoring7
5002 - Florida STORET / WIN1

Dissolved Oxygen Saturation - Discrete

Seasonal Kendall-Tau Trend Analysis

Scatter plot of monthly average dissolved oxygen saturation over time. If the time series included ten or more years of discrete observations, a significant (blue) or non-significant (magenta) trend line is also shown. Only dissolved oxygen saturation values measured in the field (circles) are included in the plot.
Scatter plot of monthly average dissolved oxygen saturation over time. If the time series included ten or more years of discrete observations, a significant (blue) or non-significant (magenta) trend line is also shown. Only dissolved oxygen saturation values measured in the field (circles) are included in the plot.
Seasonal Kendall-Tau Trend Analysis for Dissolved Oxygen Saturation
Activity Type Statistical Trend Sample Count Years with Data Period of Record Median tau Sen Intercept Sen Slope p
Field Significantly increasing trend 8088 32 1992 - 2025 91.1 0.1068 88.0408 0.2642 0.0427

Monthly average dissolved oxygen saturation increased by 0.26% per year.

Map showing location of discrete water quality sampling locations within the boundaries of Boca Ciega Bay Aquatic Preserve. The bubble size on the maps above reflect the amount of data available at each sampling site.
Map showing location of discrete water quality sampling locations within the boundaries of Boca Ciega Bay Aquatic Preserve. The bubble size on the maps above reflect the amount of data available at each sampling site.
Programs contributing data for Dissolved Oxygen Saturation
ProgramID N_Data YearMin YearMax
4067 5110 1995 2023
5002 2971 2010 2025
102 10 1992 1992
95 1 2017 2017

Program names:

95 - Harmful Algal Bloom Marine Observation Network2
102 - National Status and Trends Mussel Watch8
4067 - Tampa Bay Benthic Monitoring7
5002 - Florida STORET / WIN1

pH - Discrete

Seasonal Kendall-Tau Trend Analysis

Scatter plot of monthly average pH over time. If the time series included ten or more years of discrete observations, a significant (blue) or non-significant (magenta) trend line is also shown. Only pH values measured in the field (circles) are included in the plot.
Scatter plot of monthly average pH over time. If the time series included ten or more years of discrete observations, a significant (blue) or non-significant (magenta) trend line is also shown. Only pH values measured in the field (circles) are included in the plot.
Seasonal Kendall-Tau Trend Analysis for pH
Activity Type Statistical Trend Sample Count Years with Data Period of Record Median tau Sen Intercept Sen Slope p
Field Significantly decreasing trend 27836 38 1974 - 2025 8.1 -0.1133 8.1337 -0.0017 0.0014

Monthly average pH decreased by less than 0.01 pH units per year.

Map showing location of discrete water quality sampling locations within the boundaries of Boca Ciega Bay Aquatic Preserve. The bubble size on the maps above reflect the amount of data available at each sampling site.
Map showing location of discrete water quality sampling locations within the boundaries of Boca Ciega Bay Aquatic Preserve. The bubble size on the maps above reflect the amount of data available at each sampling site.
Programs contributing data for pH
ProgramID N_Data YearMin YearMax
5002 12858 1995 2025
69 10576 1989 2024
4067 4248 1995 2023
95 205 1974 2018
115 10 2000 2003
103 3 2015 2015

Program names:

69 - Fisheries-Independent Monitoring (FIM) Program6
95 - Harmful Algal Bloom Marine Observation Network2
103 - EPA STOrage and RETrieval Data Warehouse (STORET)/WQX3
115 - Environmental Monitoring Assessment Program4
4067 - Tampa Bay Benthic Monitoring7
5002 - Florida STORET / WIN1

Salinity - Discrete

Seasonal Kendall-Tau Trend Analysis

Scatter plot of monthly average salinity over time. If the time series included ten or more years of discrete observations, significant (blue) or non-significant (magenta) trend lines are also shown. Discrete salinity values derived from grab samples analyzed in the field (circles) or the laboratory (triangles) are both included in the plot.
Scatter plot of monthly average salinity over time. If the time series included ten or more years of discrete observations, significant (blue) or non-significant (magenta) trend lines are also shown. Discrete salinity values derived from grab samples analyzed in the field (circles) or the laboratory (triangles) are both included in the plot.
Seasonal Kendall-Tau Trend Analysis for Salinity
Activity Type Statistical Trend Sample Count Years with Data Period of Record Median tau Sen Intercept Sen Slope p
All No significant trend 28282 60 1954 - 2025 32.64 0.0509 31.9378 0.0064 0.1348

Salinity showed no detectable trend between 1954 and 2025.

Map showing location of discrete water quality sampling locations within the boundaries of Boca Ciega Bay Aquatic Preserve. The bubble size on the maps above reflect the amount of data available at each sampling site.
Map showing location of discrete water quality sampling locations within the boundaries of Boca Ciega Bay Aquatic Preserve. The bubble size on the maps above reflect the amount of data available at each sampling site.
Programs contributing data for Salinity
ProgramID N_Data YearMin YearMax
5002 14015 1995 2025
69 10821 1989 2024
4067 2564 1995 2023
95 909 1954 2018
115 10 2000 2003
102 10 1992 1992
118 2 2015 2015

Program names:

69 - Fisheries-Independent Monitoring (FIM) Program6
95 - Harmful Algal Bloom Marine Observation Network2
102 - National Status and Trends Mussel Watch8
115 - Environmental Monitoring Assessment Program4
118 - National Aquatic Resource Surveys, National Coastal Condition Assessment5
4067 - Tampa Bay Benthic Monitoring7
5002 - Florida STORET / WIN1

Secchi Depth - Discrete

Seasonal Kendall-Tau Trend Analysis

Scatter plot of monthly average Secchi depth over time. If the time series included ten or more years of discrete observations, a significant (blue) or non-significant (magenta) trend line is also shown. Secchi depth is only measured in the field (circles).
Scatter plot of monthly average Secchi depth over time. If the time series included ten or more years of discrete observations, a significant (blue) or non-significant (magenta) trend line is also shown. Secchi depth is only measured in the field (circles).
Seasonal Kendall-Tau Trend Analysis for Secchi Depth
Activity Type Statistical Trend Sample Count Years with Data Period of Record Median tau Sen Intercept Sen Slope p
Field Significantly decreasing trend 10274 32 1994 - 2025 -1.1 -0.3044 -0.9659 -0.0129 0

Monthly average Secchi depth became deeper by 0.01 m per year, indicating an increase in water clarity.

Map showing location of discrete water quality sampling locations within the boundaries of Boca Ciega Bay Aquatic Preserve. The bubble size on the maps above reflect the amount of data available at each sampling site.
Map showing location of discrete water quality sampling locations within the boundaries of Boca Ciega Bay Aquatic Preserve. The bubble size on the maps above reflect the amount of data available at each sampling site.
Programs contributing data for Secchi Depth
ProgramID N_Data YearMin YearMax
69 9739 1994 2024
5002 530 2010 2025
115 4 2000 2002
103 1 2015 2015

Program names:

69 - Fisheries-Independent Monitoring (FIM) Program6
103 - EPA STOrage and RETrieval Data Warehouse (STORET)/WQX3
115 - Environmental Monitoring Assessment Program4
5002 - Florida STORET / WIN1

Total Nitrogen - Discrete

Total Nitrogen Calculation:

The logic for calculated Total Nitrogen was provided by Kevin O’Donnell and colleagues at FDEP (with the help of Jay Silvanima, Watershed Monitoring Section). The following logic is used, in this order, based on the availability of specific nitrogen components.

  1. TN = TKN + NO3O2;
  2. TN = TKN + NO3 + NO2;
  3. TN = ORGN + NH4 + NO3O2;
  4. TN = ORGN + NH4 + NO2 + NO3;
  5. TN = TKN + NO3;
  6. TN = ORGN + NH4 + NO3;

Additional Information:

  • Rules for use of sample fraction:
    • Florida Department of Environmental Protection (FDEP) report that if both “Total” and “Dissolved” components are reported, only “Total” is used. If the total is not reported, then the dissolved components are used as a best available replacement.
    • Total nitrogen calculations are done using nitrogen components with the same sample fraction, nitrogen components with mixed total/dissolved sample fractions are not used. In other words, total nitrogen can be calculated when TKN and NO3O2 are both total sample fractions, or when both are dissolved sample fractions. Future calculations of total nitrogen values may be based on components with mixed sample fractions.
  • Values inserted into data:
    • ParameterName = “Total Nitrogen”
    • SEACAR_QAQCFlagCode = “1Q”
    • SEACAR_QAQC_Description = “SEACAR Calculated”

Seasonal Kendall-Tau Trend Analysis

Scatter plot of monthly average total nitrogen over time. If the time series included ten or more years of discrete observations, a significant (blue) or non-significant (magenta) trend line is also shown. Only nitrogen values obtained from laboratory analyses (triangles) are included in the plot.
Scatter plot of monthly average total nitrogen over time. If the time series included ten or more years of discrete observations, a significant (blue) or non-significant (magenta) trend line is also shown. Only nitrogen values obtained from laboratory analyses (triangles) are included in the plot.
Seasonal Kendall-Tau Trend Analysis for Total Nitrogen
Activity Type Statistical Trend Sample Count Years with Data Period of Record Median tau Sen Intercept Sen Slope p
Lab Significantly increasing trend 2977 26 1999 - 2025 0.55 0.2502 0.489 0.007 0

Monthly average total nitrogen increased by 0.01 mg/L per year.

Map showing location of discrete water quality sampling locations within the boundaries of Boca Ciega Bay Aquatic Preserve. The bubble size on the maps above reflect the amount of data available at each sampling site.
Map showing location of discrete water quality sampling locations within the boundaries of Boca Ciega Bay Aquatic Preserve. The bubble size on the maps above reflect the amount of data available at each sampling site.
Programs contributing data for Total Nitrogen
ProgramID N_Data YearMin YearMax
5002 2961 1999 2025
103 11 2000 2003
115 5 2000 2003

Program names:

103 - EPA STOrage and RETrieval Data Warehouse (STORET)/WQX3
115 - Environmental Monitoring Assessment Program4
5002 - Florida STORET / WIN1

Total Phosphorus - Discrete

Seasonal Kendall-Tau Trend Analysis

Scatter plot of monthly average total phosphorus over time. If the time series included ten or more years of discrete observations, a significant (blue) or non-significant (magenta) trend line is also shown. Only phosphorus values obtained from laboratory analyses (triangles) are included in the plot.
Scatter plot of monthly average total phosphorus over time. If the time series included ten or more years of discrete observations, a significant (blue) or non-significant (magenta) trend line is also shown. Only phosphorus values obtained from laboratory analyses (triangles) are included in the plot.
Seasonal Kendall-Tau Trend Analysis for Total Phosphorus
Activity Type Statistical Trend Sample Count Years with Data Period of Record Median tau Sen Intercept Sen Slope p
Lab Significantly decreasing trend 2732 26 1999 - 2025 0.05 -0.1118 0.0644 -0.0004 0.0106

Monthly average total phosphorus decreased by less than 0.01 mg/L per year.

Map showing location of discrete water quality sampling locations within the boundaries of Boca Ciega Bay Aquatic Preserve. The bubble size on the maps above reflect the amount of data available at each sampling site.
Map showing location of discrete water quality sampling locations within the boundaries of Boca Ciega Bay Aquatic Preserve. The bubble size on the maps above reflect the amount of data available at each sampling site.
Programs contributing data for Total Phosphorus
ProgramID N_Data YearMin YearMax
5002 2751 1999 2025
103 10 2000 2015
115 5 2000 2003

Program names:

103 - EPA STOrage and RETrieval Data Warehouse (STORET)/WQX3
115 - Environmental Monitoring Assessment Program4
5002 - Florida STORET / WIN1

Total Suspended Solids - Discrete

Seasonal Kendall-Tau Trend Analysis

Scatter plot of monthly average total suspended solids (TSS) over time. If the time series included ten or more years of discrete observations, a significant (blue) or non-significant (magenta) trend line is also shown. Only TSS values obtained from laboratory analyses (triangles) are included in the plot.
Scatter plot of monthly average total suspended solids (TSS) over time. If the time series included ten or more years of discrete observations, a significant (blue) or non-significant (magenta) trend line is also shown. Only TSS values obtained from laboratory analyses (triangles) are included in the plot.
Seasonal Kendall-Tau Trend Analysis for Total Suspended Solids
Activity Type Statistical Trend Sample Count Years with Data Period of Record Median tau Sen Intercept Sen Slope p
Lab Significantly decreasing trend 2782 22 2002 - 2025 12 -0.3101 16.1446 -0.3218 0

Monthly average total suspended solids decreased by 0.32 mg/L per year, indicating an increase in water clarity.

Map showing location of discrete water quality sampling locations within the boundaries of Boca Ciega Bay Aquatic Preserve. The bubble size on the maps above reflect the amount of data available at each sampling site.
Map showing location of discrete water quality sampling locations within the boundaries of Boca Ciega Bay Aquatic Preserve. The bubble size on the maps above reflect the amount of data available at each sampling site.
Programs contributing data for Total Suspended Solids
ProgramID N_Data YearMin YearMax
5002 2795 2001 2025

Program names:

5002 - Florida STORET / WIN1

Turbidity - Discrete

Seasonal Kendall-Tau Trend Analysis

Scatter plot of monthly average turbidity over time. If the time series included ten or more years of discrete observations, a significant (blue) or non-significant (magenta) trend line is also shown. Only turbidity values measured in the laboratory (triangles) are included in the plot.
Scatter plot of monthly average turbidity over time. If the time series included ten or more years of discrete observations, a significant (blue) or non-significant (magenta) trend line is also shown. Only turbidity values measured in the laboratory (triangles) are included in the plot.
Seasonal Kendall-Tau Trend Analysis for Turbidity
Activity Type Statistical Trend Sample Count Years with Data Period of Record Median tau Sen Intercept Sen Slope p
Lab Significantly increasing trend 7053 29 1995 - 2025 2.6 0.1119 2.7911 0.0313 0.0053

Monthly average turbidity increased by 0.03 NTU per year, indicating a decrease in water clarity.

Map showing location of discrete water quality sampling locations within the boundaries of Boca Ciega Bay Aquatic Preserve. The bubble size on the maps above reflect the amount of data available at each sampling site.
Map showing location of discrete water quality sampling locations within the boundaries of Boca Ciega Bay Aquatic Preserve. The bubble size on the maps above reflect the amount of data available at each sampling site.
Programs contributing data for Turbidity
ProgramID N_Data YearMin YearMax
5002 7139 1995 2025
95 2 2004 2004

Program names:

95 - Harmful Algal Bloom Marine Observation Network2
5002 - Florida STORET / WIN1

Water Temperature - Discrete

Seasonal Kendall-Tau Trend Analysis

Scatter plot of monthly average water temperature over time. If the time series included ten or more years of discrete observations, a significant (blue) or non-significant (magenta) trend line is also shown. Only water temperature measurements taken in the field (circles) are included in the plot.
Scatter plot of monthly average water temperature over time. If the time series included ten or more years of discrete observations, a significant (blue) or non-significant (magenta) trend line is also shown. Only water temperature measurements taken in the field (circles) are included in the plot.
Seasonal Kendall-Tau Trend Analysis for Water Temperature
Activity Type Statistical Trend Sample Count Years with Data Period of Record Median tau Sen Intercept Sen Slope p
Field Significantly increasing trend 31128 62 1954 - 2025 27.1 0.0869 24.5507 0.0108 0.0055

Monthly average water temperature increased by 0.01°C per year.

Map showing location of discrete water quality sampling locations within the boundaries of Boca Ciega Bay Aquatic Preserve. The bubble size on the maps above reflect the amount of data available at each sampling site.
Map showing location of discrete water quality sampling locations within the boundaries of Boca Ciega Bay Aquatic Preserve. The bubble size on the maps above reflect the amount of data available at each sampling site.
Programs contributing data for Water Temperature
ProgramID N_Data YearMin YearMax
5002 14270 1995 2025
69 10843 1989 2024
4067 5015 1995 2023
95 981 1954 2018
115 10 2000 2003
102 10 1992 1992

Program names:

69 - Fisheries-Independent Monitoring (FIM) Program6
95 - Harmful Algal Bloom Marine Observation Network2
102 - National Status and Trends Mussel Watch8
115 - Environmental Monitoring Assessment Program4
4067 - Tampa Bay Benthic Monitoring7
5002 - Florida STORET / WIN1

Submerged Aquatic Vegetation

The data file used is: All_SAV_Parameters-2025-Sep-04.txt

Submerged aquatic vegetation (SAV) refers to plants and plant-like macroalgae species that live entirely underwater. The two primary categories of SAV inhabiting Florida estuaries are benthic macroalgae and seagrasses. They often grow together in dense beds or meadows that carpet the seafloor. Macroalgae include multicellular species of green, red and brown algae that often live attached to the substrate by a holdfast. They tend to grow quickly and can tolerate relatively high nutrient levels, making them a threat to seagrasses and other benthic habitats in areas with poor water quality. In contrast, seagrasses are grass-like, vascular, flowering plants that are attached to the seafloor by extensive root systems. Seagrasses occur throughout the coastal areas of Florida, including protected bays and lagoons as well as deeper offshore waters on the continental shelf. Seagrasses have taken advantage of the broad, shallow shelf and clear water to produce two of the most extensive seagrass beds anywhere in continental North America.

Parameters

Percent Cover measures the fraction of an area of seafloor that is covered by SAV, usually estimated by evaluating multiple small areas of seafloor. Percent cover is often estimated for total SAV, individual types of vegetation (seagrass, attached algae, drift algae) and individual species.

Frequency of Occurrence was calculated as the number of times a taxon was observed in a year divided by the number of sampling events, multiplied by 100. Analysis is conducted at the quadrat level and is inclusive of all quadrats (i.e., quadrats evaluated using Braun-Blanquet, modified Braun-Blanquet, and percent cover.”

Species

Turtle grass (Thalassia testudinum) is the largest of the Florida seagrasses, with longer, thicker blades and deeper root structures than any of the other seagrasses. It is considered a climax seagrass species.

Shoal grass (Halodule wrightii) is an early colonizer of vegetated areas and usually grows in water too shallow for other species except widgeon grass. It can often tolerate larger salinity ranges than other seagrass species. Shoal grass is characterized by thin, flat blades, that are narrower than turtle grass blades.

Manatee grass (Syringodium filiforme) is easily recognizable because its leaves are thin and cylindrical instead of the flat, ribbon-like form shared by many other seagrass species. The leaves can grow up to half a meter in length. Manatee grass is usually found in mixed seagrass beds or small, dense monospecific patches.

Widgeon grass (Ruppia maritima) grows in both fresh and salt water and is widely distributed throughout Florida’s estuaries in less saline areas, particularly in inlets along the east coast. This species resembles shoal grass in certain environments but can be identified by the pointed tips of its leaves.

Three species of Halophila spp. are found in Florida - Star grass (Halophila engelmannii), Paddle grass (Halophila decipiens), and Johnson’s seagrass (Halophila johnsonii). These are smaller, more fragile seagrasses than other Florida species and are considered ephemeral. They grow along a single long rhizome, with short blades. These species are not well-studied, although surveys are underway to define their ecological roles.

Notes

Star grass, Paddle grass, and Johnson’s seagrass will be grouped together and listed as Halophila spp. in the following managed areas. This is because several surveys did not specify to the species level:

  • Banana River Aquatic Preserve

  • Indian River-Malabar to Vero Beach Aquatic Preserve

  • Indian River-Vero Beach to Ft. Pierce Aquatic Preserve

  • Jensen Beach to Jupiter Inlet Aquatic Preserve

  • Loxahatchee River-Lake Worth Creek Aquatic Preserve

  • Mosquito Lagoon Aquatic Preserve

  • Biscayne Bay Aquatic Preserve

  • Florida Keys National Marine Sanctuary

Maps showing the temporal scope of SAV sampling sites within the boundaries of Boca Ciega Bay Aquatic Preserve by Program name.
Maps showing the temporal scope of SAV sampling sites within the boundaries of Boca Ciega Bay Aquatic Preserve by Program name.

Click here to view spatio-temporal plots on GitHub.

Sampling locations by Program:

Map showing SAV sampling sites within the boundaries of Boca Ciega Bay Aquatic Preserve. The point size reflects the number of samples at a given sampling site.
Map showing SAV sampling sites within the boundaries of Boca Ciega Bay Aquatic Preserve. The point size reflects the number of samples at a given sampling site.
Program Information for Submerged Aquatic Vegetation
ProgramID N-Data YearMin YearMax method Sample Locations
565 2730 1998 2024 Braun Blanquet 10
564 54 2019 2019 Percent Cover 7

Program names:

564 - Western Pinellas County Seagrass Monitoring9
565 - Tampa Bay Seagrass Monitoring10

Scatter plots of median percent cover of submerged aquatic vegetation over time by group. Plots for time series that included five or more years of observations show the estimated trend as a blue line.
Scatter plots of median percent cover of submerged aquatic vegetation over time by group. Plots for time series that included five or more years of observations show the estimated trend as a blue line.
Trends in median percent cover for various seagrass species in Boca Ciega Bay Aquatic Preserve - simplified
Trends in median percent cover for various seagrass species in Boca Ciega Bay Aquatic Preserve - simplified
Percent Cover Trend Analysis for Boca Ciega Bay Aquatic Preserve
CommonName Trend Significance (0.05) Period of Record LME-Intercept LME-Slope p
Drift algae Insufficient data to calculate trend - - - -
Shoal grass No significant trend 1998 - 2024 47.97762 -0.198289 0.3776091
No grass in quadrat Model did not fit the available data 1998 - 2024 - - -
Manatee grass Model did not fit the available data 2003 - 2024 - - -
Turtle grass Significantly decreasing trend 1998 - 2024 52.32631 -0.496445 0.0492310
Halophila, unk. Insufficient data to calculate trend - - - -

An annual decrease in percent cover was observed for turtle grass (-0.5%). No detectable change in percent cover was observed for shoal grass. Trends in percent cover could not be evaluated for unknown Halophila and drift algae due to insufficient data, and the model could not be fitted for manatee grass.

Frequency of occurrence for various seagrass species in Boca Ciega Bay Aquatic Preserve
Frequency of occurrence for various seagrass species in Boca Ciega Bay Aquatic Preserve

SAV Water Column Analysis

The following parameters are available for Boca Ciega Bay Aquatic Preserve within the SAV_WC_Report:

  • Chlorophyll a

  • Dissolved Oxygen

  • Dissolved Oxygen Saturation

  • pH

  • Salinity

  • Secchi Depth

  • Water Temperature

  • Total Nitrogen

  • Total Suspended Solids

  • Turbidity

Access the reports here: DRAFT_SAV_WC_Report_2024-11-20.pdf

Nekton

The data file used is: All_NEKTON_Parameters-2025-Sep-04.txt

Bar graph(s) of annual average nekton richness over time for species groups occurring in at least 1% of samples. The bar colors represent species groups including bony fishes, cartilaginous fishes, decapod crustaceans (e.g., shrimps, crabs, and lobsters), and cephalopods (e.g., squid). Gear types and sizes are indicated in the panel label.
Bar graph(s) of annual average nekton richness over time for species groups occurring in at least 1% of samples. The bar colors represent species groups including bony fishes, cartilaginous fishes, decapod crustaceans (e.g., shrimps, crabs, and lobsters), and cephalopods (e.g., squid). Gear types and sizes are indicated in the panel label.
Nekton Species Richness
Gear Type Sample Count Number of Years Period of Record Median N of Taxa Mean N of Taxa
Trawl (6.1) 1833 36 1989 - 2024 0.45 0.77
Seine (183) 1747 29 1996 - 2024 0.15 0.19

The median annual number of taxa was 0.15 based on 1,747 observations collected by 183-meter seine between 1996 and 2024, and the median annual number of taxa was 0.45 based on 1,833 observations collected by 6.1-meter trawl between 1989 and 2024.

Map showing location of nekton sampling locations within the boundaries of Boca Ciega Bay Aquatic Preserve. The bubble size on the maps above reflect the amount of data available at each sampling site.
Map showing location of nekton sampling locations within the boundaries of Boca Ciega Bay Aquatic Preserve. The bubble size on the maps above reflect the amount of data available at each sampling site.

Species list

Acanthophora sp.1 Etropus crossotus2 No fish
Acanthostracion quadricornis2 Eucinostomus argenteus2 No grass in quadrat1
Achirus lineatus2 Eucinostomus gula2 Ocyurus chrysurus2
Aetobatus narinari2 Eucinostomus harengulus2 Ogcocephalus cubifrons2
Albula vulpes2 Eucinostomus spp.2 Ogcocephalus spp.2
Alpheidae spp.2 Eugerres plumieri2 Oligoplites saurus2
Aluterus schoepfii2 Floridichthys carpio2 Ophidion grayi2
Aluterus scriptus2 Fundulus grandis2 Ophidion holbrookii2
Anarchopterus criniger2 Fundulus similis2 Ophidion josephi2
Anchoa cubana2 Gerres cinereus2 Opisthonema oglinum2
Anchoa hepsetus2 Gobiesox strumosus2 Opsanus beta2
Anchoa lyolepis2 Gobiidae spp.2 Oreochromis aureus2
Anchoa mitchilli2 Gobionellus oceanicus2 Orthopristis chrysoptera2
Anchoa spp.2 Gobiosoma bosc2 Ostraciidae spp.2
Ancylopsetta quadrocellata2 Gobiosoma longipala2 Paraclinus fasciatus2
Anguilla rostrata2 Gobiosoma robustum2 Paraclinus marmoratus2
Archosargus probatocephalus2 Gobiosoma spp.2 Paralichthys albigutta2
Argopecten irradians Gracilaria sp.1 Penaeidae spp.2
Argopecten spp. Haemulon aurolineatum2 Penaeus duorarum2
Ariopsis felis2 Haemulon plumierii2 Peprilus burti2
Astroscopus ygraecum2 Haemulon spp.2 Peprilus paru2
Attached algae1 Halichoeres bivittatus2 Poecilia latipinna2
Bagre marinus2 Halodule wrightii1 Pogonias cromis2
Bairdiella chrysoura2 Halophila sp.1 Pomatomus saltatrix2
Bathygobius soporator2 Harengula jaguana2 Portunus spp.2
Bothidae spp.2 Hemicaranx amblyrhynchus2 Prionotus scitulus2
Brevoortia spp.2 Hemiramphus brasiliensis2 Prionotus spp.2
Calamus arctifrons2 Hippocampus erectus2 Prionotus tribulus2
Calamus penna2 Hippocampus zosterae2 Pseudocrenilabrinae2
Calamus proridens2 Hypleurochilus caudovittatus2 Rachycentron canadum2
Calamus spp.2 Hypnea1 Rhinoptera bonasus2
Callinectes ornatus2 Hyporhamphus meeki2 Rimapenaeus constrictus2
Callinectes sapidus2 Hyporhamphus spp.2 Sardinella aurita2
Callinectes similis2 Hyporhamphus unifasciatus2 Sarotherodon melanotheron2
Callinectes spp.2 Hypsoblennius hentz2 Sciaenops ocellatus2
Caranx bartholomaei2 Kyphosus sectatrix2 Scomberomorus maculatus2
Caranx crysos2 Kyphosus spp.2 Scorpaena brasiliensis2
Caranx hippos2 Lachnolaimus maximus2 Selene vomer2
Caranx latus2 Lactophrys trigonus2 Serraniculus pumilio2
Caranx spp.2 Lagodon rhomboides2 Serranus subligarius2
Carcharhinus limbatus2 Leiostomus xanthurus2 Sicyonia brevirostris2
Caulerpa sertularioides1 Limulus polyphemus Sicyonia laevigata2
Centropomus undecimalis2 Lobotes surinamensis2 Sicyonia spp.2
Centropristis striata2 Lucania parva2 Sicyonia typica2
Chaetodipterus faber2 Lutjanus analis2 Sphoeroides nephelus2
Chaetodon capistratus2 Lutjanus apodus2 Sphoeroides spengleri2
Chaetodon ocellatus2 Lutjanus griseus2 Sphyraena barracuda2
Chasmodes saburrae2 Lutjanus spp.2 Sphyraena borealis2
Chelonia mydas2 Lutjanus synagris2 Sphyraena guachancho2
Chilomycterus schoepfii2 Lyngbya sp. Sphyrna tiburo2
Chloroscombrus chrysurus2 Menidia spp.2 Stephanolepis setifer2
Citharichthys cornutus2 Menippe mercenaria2 Strongylura marina2
Citharichthys macrops2 Menippe spp.2 Strongylura notata2
Cynoscion arenarius2 Menticirrhus americanus2 Strongylura timucu2
Cynoscion nebulosus2 Menticirrhus littoralis2 Syacium papillosum2
Cyprinodon variegatus2 Menticirrhus saxatilis2 Symphurus plagiusa2
Diapterus auratus2 Menticirrhus spp.2 Syngnathus floridae2
Diodon holocanthus2 Microgobius gulosus2 Syngnathus louisianae2
Diplectrum formosum2 Microgobius spp.2 Syngnathus scovelli2
Diplectrum spp.2 Microgobius thalassinus2 Syngnathus springeri2
Diplodus holbrookii2 Micropogonias undulatus2 Synodus foetens2
Dorosoma petenense2 Monacanthus ciliatus2 Syringodium filiforme1
Drift algae1 Mugil cephalus2 Thalassia testudinum1
Drift red algae1 Mugil curema2 Trachinotus carolinus2
Echeneis naucrates2 Mugil spp.2 Trachinotus falcatus2
Echeneis neucratoides2 Mugil trichodon2 Trinectes maculatus2
Echeneis spp.2 Mycteroperca bonaci2 Tylosurus crocodilus2
Elops saurus2 Mycteroperca microlepis2 Unidentified species
Engraulidae spp.2 Myrophis punctatus2 Urophycis floridana2
Epinephelus itajara2 Narcine bancroftii2 Acanthophora sp.1
Epinephelus morio2 Nicholsina usta2 Acanthostracion quadricornis2

1 - Submerged Aquatic Vegetation, 2 - Nekton

References

1.
Florida Department of Environmental Protection (DEP). Florida STORET / WIN. (2024).
2.
Florida Fish and Wildlife Conservation Commission (FWC); Florida Fish and Wildlife Research Institute (FWRI). Harmful Algal Bloom Marine Observation Network. (2018).
3.
U.S. Environmental Protection Agency (EPA). EPA STOrage and RETrieval Data Warehouse (STORET)/WQX. (2023).
4.
U.S. Environmental Protection Agency (EPA); Office of Research and Development. Environmental Monitoring Assessment Program. (2004).
5.
U.S. Environmental Protection Agency (EPA); Office of Water; National Oceanic and Atmospheric Administration (NOAA); U.S. Geological Survey (USGS); U.S. Fish and Wildlife Service (USFWS); National Estuary Program (NEP); coastal states. National Aquatic Resource Surveys, National Coastal Condition Assessment. (2021).
6.
Florida Fish and Wildlife Conservation Commission (FWC). Fisheries-Independent Monitoring (FIM) Program. (2022).
7.
Tampa Bay Estuary Program. Tampa Bay Benthic Monitoring. (2022).
8.
National Oceanic and Atmospheric Administration (NOAA); Center for Coastal Monitoring and Assessment. National Status and Trends Mussel Watch. (2000).
9.
Pinellas County (Florida); Department of Environmental Management; Tampa Bay Estuary Program (TBEP). Western Pinellas County Seagrass Monitoring. (2019).
10.
Tampa Bay Interagency Seagrass Monitoring Program; Tampa Bay Estuary Program (TBEP). Tampa Bay Seagrass Monitoring. (2023).