Technical Support Document for U.S. EPA’s Proposed Rule for Numeric Nutrient Criteria, 

Volume 2 Coastal Waters 

Appendix A.

Appendix A: A Review of Reference

Conditions in Florida’s Coastal Waters 

November 30, 2012 
 

Technical Support Document for U.S. EPA’s Proposed Rule for Numeric Nutrient Criteria, 

Volume 2 Coastal Waters 

Contents 

1. Introduction....................................................................................................................... A-1
 

2. Coastal Systems................................................................................................................. A-2
 

2.1. Physical Characteristics................................................................................................ A-2
 

2.1.1. Impaired Coastal Waters.................................................................................. A-9
 

2.2. Resident Biological Communities................................................................................ A-9
 

2.2.1. Northwest Panhandle ....................................................................................... A-9
 

2.2.2. West Gulf Coast............................................................................................. A-10
 

2.2.3. Atlantic Coast................................................................................................. A-12
 

2.3. Status of Neighboring Estuarine Systems .................................................................. A-13
 

2.3.1. Northwest Panhandle ..................................................................................... A-13
 

2.3.2. West Gulf Coast............................................................................................. A-14
 

2.3.3. Atlantic Coast................................................................................................. A-16
 

3. Summary of Regional Trends ........................................................................................ A-17
 

4. References........................................................................................................................ A-19
 

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Technical Support Document for U.S. EPA’s Proposed Rule for Numeric Nutrient Criteria, 

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Figures 

Figure A-1. Coastal regions and their segments for the purpose of deriving numeric
 

nutrient criteria for Florida’s coastal waters............................................................ A-2
 

Figure A-2. Northwest Gulf Coast area map .............................................................................. A-3
 

Figure A-3. Northern Gulf of Mexico summer surface current climatology (Johnson 

2008)........................................................................................................................ A-4
 

Figure A-4. Northern Gulf of Mexico non-summer surface current climatology (Johnson 

2008)........................................................................................................................ A-4
 

Figure A-5. Area map of Florida’s west Gulf Coast................................................................... A-6
 

Figure A-6. Area map of Florida’s Atlantic Coast ..................................................................... A-8
 

Figure A-7. 1998-2009 chlorophyllRS a values (mg/m3

) for Florida’s three defined coastal
 

regions ................................................................................................................... A-19
 

Tables 

Table A-1. WBIDs with EPA-approved 303(d) listings along the Atlantic and Gulf coasts
 

of Florida ................................................................................................................. A-9
 

Table A-2. Average annual surface and bottom concentrations of phosphate and nitrate
 

(as mg/L) at the 33, 82, and 164 ft (10, 25, and 50 m) isobaths (adapted from
 

Vargo et al. 2008). Each value is the average of monthly measurements
 

(±SD). .................................................................................................................... A-15
 

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Abbreviations and Acronyms 

DO dissolved oxygen 

EPA U.S. Environmental Protection Agency 

ft feet 

ft2 square feet 

g gram 

HAB harmful algal bloom 

km kilometer 

km2 square kilometer 

L liter 

m meter 

m

2 square meter 

mg/L milligrams per liter 

mi mile 

mi2 square mile 

μM micromole 

NH4 ammonium 

ng nanogram 

NO3 nitrate 

PO4 phosphate 

TN total nitrogen 

TP total phosphorus 

WBID water body identification number 

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Technical Support Document for U.S. EPA’s Proposed Rule for Numeric Nutrient Criteria, 

Volume 2 Coastal Waters 

1. Introduction 

The objective of this document is to provide a thorough summary of the best available 

information concerning the state of water quality conditions in Florida’s coastal waters. 

Currently, Florida coastal waters have few nutrient (TN, TP, chlorophyll a) field data available, 

as sparse observations have been collected on the northwest Gulf Coast and Atlantic Coast. 

There are also no actual measurements of nutrients for many coastal areas, and a deficient 

number of existing assessments to determine whether coastal impairments currently exist. 

Despite a lack of information regarding impaired coastal waters in Florida’s Impaired Waters 

Rule and monitoring programs, high rates of nutrient transport have occasionally been linked to 

Florida’s growing human population, various industries, and agriculture (Lapointe et al. 2005; 

Lapointe and Bedford 2007; Vargo et al. 2008). Given the variability of coastal water quality 

data available in Florida, information on neighboring estuarine systems was also collected to 

establish multiple lines of evidence on the reference condition of these waters and whether there 

is any reasonable indication of water quality degradation with respect to nutrients. Thus, known 

conditions in neighboring estuarine waters can inform the U.S. Environmental Protection 

Agency (EPA) of the reference conditions in nearby coastal segments. 

For this review, coastal waters are defined by EPA as marine waters up to three nautical miles 

from shore, but exclude estuaries that are generally semi-enclosed waters connected to the open 

sea, defined at the upstream limit by average salinity equal to 2.7 practical salinity units, and at 

the seaward margin by the natural limits of the semi-enclosed basin. Florida coastal waters have 

been organized into three regions (Figure A-1): Atlantic Coast (between Biscayne Bay and the 

Georgia State border), West Florida Shelf (between Anclote Bay and Rookery Bay), and Florida 

Panhandle (between Alabama State border and St. Joseph Bay). The information collected for 

each coastal region can help EPA deduce whether the numeric criteria derived under a reference 

condition approach will not only be protective of water quality in these areas, but also of their 

designated uses. While no conclusions will be made in this review, the accumulation of available 

information will help EPA determine reference conditions for these waters. 

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Technical Support Document for U.S. EPA’s Proposed Rule for Numeric Nutrient Criteria, 

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Figure A-1. Coastal regions and their segments for the purpose of deriving numeric nutrient criteria for Florida’s 

coastal waters 

2. Coastal Systems 

2.1. Physical Characteristics 

Coastal systems receive nutrients from several major inputs including rivers, groundwater, and 

atmospheric deposition. The fate and transport of landward nutrients to coastal systems is a 

dynamic and complex process. Several forcing mechanisms such as winds, tides, freshwater 

inflow, and ocean currents affect the spatial and temporal nature of physical exchange between 

the nearshore and coastal environments (Hubertz et al. 2005). There are biogeochemical 

considerations that can dictate the transformation of nutrient constituents as they move along the 

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freshwater to marine continuum (Jickells 1998). Human modifications between the sea and 

interior water bodies, and control of freshwater releases, can also affect mixing and residence 

time of water constituents. 

Northwest Coast 

The northwest Gulf Coast includes the coastal portions from St. Joseph Bay to the 

Florida/Alabama border at Perdido Bay. Neighboring bays include Perdido, Pensacola, 

Choctawhatchee, St. Andrews, and St. Joseph bays (FMRI 2002) (Figure A-2). The majority of 

the region is separated from contact with the mainland and bays by barrier islands that line the 

Panhandle. There is a lack of open mixing between the water in the bays and the greater coastal 

areas in this region, due to few natural openings to the Gulf of Mexico (Livingston 2001). 

Figure A-2. Northwest Gulf Coast area map 

Wind appears to be a major factor in circulation and salinity in the nearby shallow Gulf estuaries. 

Currents in the northwest Gulf Coast change seasonally. In the summer (June to August), winds 

typically blow surface currents north, toward the shore; in non-summer months, winds blow the 

currents west/southwest (Figure A-3 and Figure A-4) (Johnson 2008). 

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Figure A-3. Northern Gulf of Mexico summer surface current climatology (Johnson 2008) 

Figure A-4. Northern Gulf of Mexico non-summer surface current climatology (Johnson 2008) 

River flow patterns are an important feature of stratification and salinity distribution, also 

impacting color, turbidity, and primary productivity in these locations. The major sources of 

freshwater surface flow into the Gulf come from Perdido Bay, Pensacola Bay, Choctawhatchee 

Bay, St. Andrews Bay, and St. Joseph Bay watersheds. In these areas, urbanization has 

contributed to the degradation of aquatic conditions, from sources such as stormwater runoff and 

sewage leakage. This has led to higher TN and TP in the water column, especially because of the 

lack of flushing in these estuarine systems (Livingston 2001). While there is historical evidence 

of biological imbalance of faunal communities and high phytoplankton productivity in the 

estuaries, there is little evidence of these effects in the neighboring coastal waters. 

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West Gulf Coast 

The west Gulf Coast is on Florida’s western central coast along the Gulf of Mexico. The stretch 

of coastal waters includes areas outside of St. Joseph Sound, Clearwater Harbor, Tampa Bay, 

Sarasota, Charlotte Harbor, and Rookery Bay (Figure A-5). Barrier islands stretch 60 miles (mi) 

(97 kilometers [km]) along the shoreline, from Tampa Bay to Charlotte Harbor (SWFWMD 

2000). The barrier islands are composed of Miocene limestone beneath Holocene and 

Pleistocene sediments (Davis et al. 2003). 

In general, waters in the West Florida Shelf are oligotrophic (Vargo et al. 2008). During the 

summer, the gulf currents flow from the south in the lower portions of the west Gulf Coast, and 

from the north in the upper portions (See Figure A-3). During non-summer months, the current 

flows from the north along the entire west Gulf Coast (see Figure A-4) (Johnson 2008). Along 

southwest Florida, land based nutrient discharges have been historically linked to the 

development of harmful algal blooms (HABs), primarily macroalgae (or seaweeds) that have 

grown with expanding urbanization of the watershed, discharges from the Peace and 

Caloosahatchee rivers, runoff from treated sewage used in agriculture, drainage from the 

Everglades Agricultural Area, and sewage leachate. A study performed by Lapointe and Bedford 

(2007) found that drifts of rhodophyte blooms off of Lee County’s coastal waters are linked to 

land based nutrient pollution. Blooms such as these affect the composition of the water column a 

considerable distance offshore, highlighting the mobility of their negative ecological impacts. 

Lapointe and Bedford (2007) showed nitrogen and phosphorus pollution extending 16 mi 

(26 km) offshore of Lee County from elevated nutrient loading during the fall of 2004, after a 

drift macroalgal community washed ashore in July and August. Between August and October, 

ammonium (NH4) concentrations on coastal reefs increased from less than or equal to 0.0028 to 

0.0183 milligrams per liter [mg/L] as nitrogen (0.20 to 1.31 μM) and soluble reactive phosphorus 

(SRP) increased from 0.009 to 0.028 mg/L as phosphorus (0.30 to 0.92 μM) (Lapointe and 

Bedford 2007).1 

In addition to macroalgae, blooms of Karenia brevis (also known as red tides) frequently occur 

on the west Gulf Coast and have been known to last for months (Vargo et al. 2008). Blooms are 

thought to initiate in offshore waters and get blown toward shore by wind and ocean currents. 

The West Florida Shelf experiences slope-shelf upwelling that is persistent, intermittent or eventrelated. The upwelling allows blooms to occur any time of the year, but the majority occurs in 

the late summer and fall. This area of the shelf also experiences fronts, where nutrient regimes 

and light conditions often favor phytoplankton accumulation and growth. It only takes 2–8 weeks 

for blooms to grow to fish-killing proportions (1–2.5x105 cells/L) once initial growth occurs 

(Tester and Steidinger 1997). In both estuaries and coastal waters off the southwest coast of 

Florida, blooms of the cyanobacterium Microcystis aeruginosa (a widely distributed species) and 

associated high levels of its toxin microcystin have raised concerns (Lapointe et al. 2005). These 

toxins have threatened designated use of these waters by calling into question the safety of the 

water for drinking, recreation, and fishing (Burns 2008). 

1 The authors reported concentrations in M (moles) or μM in the literature (in parentheses). 

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Figure A-5. Area map of Florida’s west Gulf Coast 

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Atlantic Coast 

Figure A-6 shows a map of Florida’s Atlantic Coast. Florida’s northern Atlantic Coast is 

separated from the mainland by a barrier island system consisting of numerous small bays and 

lagoons, and three inlets (St. Augustine, Matanzas, and Ponce de Leon) (FDEP 2005). Tidal 

exchange, wind patterns, and freshwater inflow are all cited as major drivers of mixing between 

estuaries and the Atlantic Ocean in this region (SJRWMD 2003). In a study using radioactive 

isotopes, Moore (1996) found that groundwater fluxes to the coastal ocean could be comparable 

to those of the region’s rivers and can also be a significant contributing factor to coastal water 

quality (Moore 1996). The literature reviewed for this document did not provide evidence that 

there were nutrient related impacts in the offshore coastal waters adjacent to estuaries in 

northeast Florida. 

The east coast of Florida is impacted by algal blooms that originate on the west coast. Gulf of 

Mexico blooms of the dinoflagellate Gymnodinium breve are occasionally carried around the 

Florida peninsula by the Loop Current and northward by the Gulf Stream (Van Dolah 2000). The 

first reported case of this was documented by Murphy et al. (1975). That bloom was attributed to 

an unusual Loop Current pattern that carried the organisms detected in late September 1972 in 

southwest Florida waters (Murphy et al. 1975). All samples collected from sites from Ft. 

Lauderdale to Cape Canaveral contained G. breve except those from the Ft. Pierce, Vero Beach, 

and Cape Canaveral areas (Murphy et al. 1975). 

Phaeophyte Dictyota spp., calcareous chlorophyte Halimeda spp., and cyanobacterium Lyngbya 

spp. blooms have occurred on oligotrophic coral reefs in the offshore areas of Dade and Broward 

counties. On northern coral reefs off Palm Beach County, blooms of the chlorophytes Codium 

spp. and Caulerpa spp. have been recurring since 1990. Data collected from water column 

monitoring of dissolved inorganic and organic nutrients, and algal tissue for carbon-nitrogenphosphorus ratios suggests that the taxonomic shifts seen in the macroalgal blooms were related 

to nitrogen-phosphorus ratio availability. For example, in a study conducted by Lapointe et al. 

(2010), nitrogen-phosphorus tissue ratios (35:1–70:1) in Dade and Broward counties were higher 

than that of Palm Beach County (33:1). The differences in nitrogen-phosphorus ratios are 

attributed to “natural patterns in geological substrata as well as anthropogenic nutrient 

enrichment of the watershed” (Collier et al. 2008; Lapointe et al. 2010). 

Between 2002 and 2004, Tichenor (2003, 2004) characterized Lyngbya blooms along the Gulf 

Stream Reef, southeast of Boyton Beach Inlet. The authors observed significant impacts to the 

reef ecosystem during and after the Lyngbya blooms including: the colonization of sponges and 

corals by algal filaments, the exclusion of reef fish, and structural damage to corals from the 

physical burden of algal colonization that eventually resulted in exposed areas and scoured 

bottoms. Further investigation into possible causes of the blooms found that discharges from the 

Delray ocean outfall (1.2 mi [1.9 km] up-current of the Gulf Stream Reef) were strongly 

correlated to the occurrence and intensity of the blooms (Tichenor 2004). 

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Figure A-6. Area map of Florida’s Atlantic Coast 

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Table A-1. WBIDs with EPA-approved 303(d) listings along the Atlantic and Gulf coasts of Florida 

WBID Estuary Date Listed Impairment 

8106 Indian River 9/2/2009 DO 

8010 Choctawhatchee/St. Andrews 5/12/2010 DO 

8037 Waccasassa 9/2/2009 Nutrients and chlorophyll a

8115 Indian River 9/2/2009 DO 

8110 Indian River 9/2/2009 DO 

8108 Indian River 9/2/2009 DO 

 

 

 

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Subsequent studies suggested a more direct link between land-based anthropogenic nutrient 

inputs and HABs. Lapointe et al. (2005), for example, determined through isotope analysis that 

nitrogen from wastewater contributed more heavily to blooms of Caulerpa branchypus in 

southeastern Florida than nitrogen from natural upwelling. A similar study by Lapointe and 

Bedford (2010) used isotope analysis to determine that C. branchypus blooms impacting coral 

reefs in southeast Florida were disproportionately enriched by land-based nutrients. Carr et al. 

(2000) observed that effluent from nearby ocean outfalls was quickly diluted and distributed over 

a wide area and unlikely to enhance C. branchypus growth in the region. 

2.1.1. Impaired Coastal Waters 

Within Florida’s three coastal regions, there are six coastal, Class III marine water body 

identification numbers (WBIDs) that are verified as impaired on FDEP’s 303(d) list of impaired 

waters approved by EPA (see Table A-1). Of these six WBIDs, five (WBIDs 8010, 8106, 8108, 

8110, and 8115) are impaired for dissolved oxygen (DO). The remaining WBID (8037), which is 

not an EPA coastal segment, is impaired for nutrients and chlorophyll a. 

2.2. Resident Biological Communities 

2.2.1. Northwest Panhandle 

Coral/Hardbottom Community: There are extensive areas of low-lying carbonate reef platforms 

in the West Florida Shelf that provide substrate for sessile benthos, including sponges, corals, 

tunicates, gorgonians, hydroids, bryozoans, attached bivalves, crinoids, and ophioroids (FMRI 

2002). 

Invertebrates: A survey of the West Florida shelf conducted in the 1970s found nematodes were 

the most abundant meiobenthic group. Harpacticoid copepods were relatively abundant. Other 

invertebrates were turbellarian, gastrotrichs, priapulids, crustacean larvae, polycheate larvae, 

kinorynchs, tardigrads, coelentorates, and halacarid mites (Alexander et al. 1977). On the basis of a 

1977–1978 survey by Dames & Moore (1979), meiobenthos were found to generally decrease with 

depth, with the greatest mean densities at depths less than 130 feet (ft) (40 meters [m]). 

The two dominant invertebrate species in the northwest Gulf Coast are Tellina versicolor and 

Crassinella martinicensis; farther east, the species are more variable. Species richness generally 

decreases with greater depths. Maximum abundances are generally observed during fall, which 

indicates spawning in the spring or summer (Dames & Moore 1979). 

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There are two species of scallops in the northwest Gulf Coast area—calico scallops (Argopecten 

gibbus) and bay scallops (A. irridians) (FMRI 2002). 

Fish: King mackerel (Scomberomorus cavalla) and Atlantic Spanish mackerel (S. maculatus) are 

migratory species found in this region during summer (Sutherland and Fable 1980). 

Two stations along the Gulf Coast Shelf were sampled by trawl during May and June of 2000. 

The fish collected at these stations included deepbody boarfish (Antigonia capros), bullseye 

grenadier (Bathygadus macrops), thickbeard grenadier (Coryphaenoides zaniophorus), tadpole 

whiptail (Squalogadus modificatus), and armored searobin (Peristedion miniatum). The 

dominant species caught are not commercially important species, but are captured as by-catch 

(Powell et al. 2003). Important commercial fisheries in the coastal area include shrimp trawl, 

blue crab trap/pot, stone crab trap/pot, and menhaden (NOAA 2009). 

Birds and Mammals: A variety of birds can be found along the northwest coast of Florida. 

Species that are around the Choctawhatchee Bay in Okaloosa County include American robins, 

yellow-bellied sapsuckers, yellow-rumped warblers, tufted titmice, finches, western tanagers, 

pelicans, herons, bald eagles, ospreys, gulls, terns, egrets, blue jays, northern mockingbirds, redheaded woodpeckers, brown thrashers, northern cardinals, cormorants, sparrows, catbirds, 

raptors, flycatchers, nuthatches, wrens, white-winged dove, purple martins, rose-breasted 

grosbeaks, veeries, green herons, gannets, and snowy plovers (Choctawhatchee Audubon Society 

No date). Black skimmers (Rhynchops niger) and least terns (Sterna antillarum) have also been 

found to nest along the northwest Gulf Coast of Florida (Gore 1991). 

A population of bottlenose dolphins (Tursiops truncates) lives in the coastal waters of 

northwestern Florida. The population estimate in 1993 was 4,191 and has not been estimated 

since (NOAA 2009). 

2.2.2. West Gulf Coast 

Seagrasses: Dawes (1985) found that the most abundant seagrass species in the Anclote Key area 

was turtle grass (Thalassia testudinum). Lush populations of this species occurred in the open 

waters between Anclote Key and the mainland. Generally, turtle grass is found in areas with 

stable salinities ranging from 25 to 40 percent at depths of 1.6–33 ft (0.5–10 m) (Dawes 1985). 

The second most abundant species around Anclote Key was manatee grass (Syringodium 

filiforme). This seagrass most commonly grows in dense beds at salinities of 20 to 40 practical 

salinity units and depths of 1.6–33 ft (0.5–10 m), although it can be found at depths of 33–66 ft 

(10–20 m) (Dawes 1985). Shoal grass (Halodule wrightii) is more tolerant of low salinities and 

can survive in salinities down to 10 percent; it is one of the first species to establish on the sand 

shoals, and is commonly found in shallow waters of 0.7 ft (0.2 m) (Dawes 1985). Star grass 

(Halophila engelmanni) is commonly found growing among turtle grass and manatee grass, 

however it is often over looked due to its small size of 2–3 in (5–8 centimeters) (Dawes 1985). 

Wigeon grass (Ruppia maritime) is only found in salinities lower than 15 practical salinity units, 

and therefore does not grow in open ocean waters. It is commonly found near the mouth of the 

Anclote River (Dawes 1985). Between 1957 and 1973 there were drastic changes to the seagrass 

beds along the barrier island of Anclote Key, just north of St. Petersburg. Aerial photos from 

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1973 showed the seagrass bed that was on the seaward side of the island entirely disappeared. 

The exact timing and the cause for the change is unknown (Hine et al. 1987). 

Coral/Hardbottom Community: Coral populations were studied in the southern portion of the 

west Gulf Coast, approximately 1,000 ft (300 m) offshore of Collier County, in waters no deeper 

than 30 ft (9 m). Four species of stony corals were found: Siderastrea siderea, Solenastrea 

hyades, Oculina robusta, and Phyllangia americana. S. siderea was the most dominant species 

observed in the study area. Two octocoral species were identified in the study area, Leptogorgia 

virgulata and L. hebes, found in low abundance (Makowski and Keyes 2011). 

Invertebrates: Sponges comprise the majority of benthic invertebrate species identified in the 

west Gulf Coast. Species include Cliona delitrix, C. langae, C. celata, Siphonodictyon 

coralliphagum, Anthosigmella varians (which are all bioeroding species), Cinachyra sp., 

Holopsamma helwigi, and Leucetta barbata (which are nonbioeroding species) (Makowski and 

Keyes 2011). 

Other benthic invertebrates (i.e., anemone, annelids, arthropods, barnacles, and bivalves) 

comprise less than 0.1 percent of the reported cover (Makowski and Keyes 2011). Bay scallops 

(A. irradians) are found along the coast of Anclote Estuary, which is at the northern end of the 

west Gulf Coast area. The average scallop densities for the 20 sample sites were consistently less 

than 5 per 6,500 square feet (ft2

) (600 square meters [m

2

]) in 1995 and 1996. Densities never 

exceeded 27 adult scallops at any station. In order to reduce pressure on low-density populations 

of bay scallops, Florida Marine Fisheries Commission eliminated recreational fisheries south of 

the Suwannee River in 1995, including the west Gulf Coast (Arnold et al. 1998). 

Fish: A 1994–1997 fish assemblage study conducted off the western coast of Florida found 

111 species, representing 38 families. The majority (79–84%) of the species caught were pinfish 

(Lagodon rhomboides), round sardinella (Sardinella aurita), round scad (Decapterus punctatus), 

Tomtate grunt (Haemulon aurolineatum), silver jenny (Eucinostomus spp.), scaled sardine 

(Harengula jaguana), and Atlantic bumper (Chloroscombrus chrysurus). The fish were most 

influenced by bottom-type differences (Pierce and Mahmoudi 2001). 

There is a recreational fishery of king mackerel (S. cavalla) off the west-central coast of Florida. 

Interviews conducted during 19 seasonal tournaments in April–May and October–November 

2004 and 2005 found that positive catch rates of king mackerel were influenced by chlorophyll a 

levels and season. Intermediate water clarity also led to higher catch rates. The red tide bloom of 

K. brevis decreased catch rates, which were attributed to decreased water quality (Wall et al. 

2009). 

In the southern portion of the west Gulf Coast, off Collier County, pelagic and benthic fish 

species include: gag groupers (Mycteroperca microlepis), juvenile grunts (Haemulon sp.), 

common snook (Centropomus undecimalis), file fish of the Moacanthidae family, leopard 

searobins (Prionotus scitulus), gray snappers (Lutjanus griseus), yellowtail snapper (Ocyurus 

chrysurus), porkfish (Anisotremus virginicus), Atlantic spadefish (Chaetodipterus faber), black 

groupers (Mycterperca bonaci), the bridled goby (Coryphopterus glaucofraenum), goliath 

groupers (Epinephelus itajara), lookdowns (Selene vomer), sheepshead seabreams (Archosargun 

probatocephalus), lizardfish (Syndous sp.), belted sandfish (Serranus subligaruis), nurse sharks 

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(Ginglymostoma cirratum), and polka-dot batfish (Ogcocephalus radiatus) (Makowski and 

Keyes 2011). 

Birds and Mammals: The whooping crane (Grus americana) was reduced to 21 individuals in 

1941/1942. To reintroduce the whooping crane into wild populations, the Chassahowitzka 

National Wildlife Refuge along Florida’s western coast was selected as a wintering ground. 

Between 2001 and 2005, 71 birds were released to the Chassahowitzka National Wildlife Refuge 

wintering site (Urbanek et al. 2010). 

2.2.3. Atlantic Coast 

Seagrasses: Six species of seagrasses commonly found in south Florida are turtle grass, manatee 

grass, shoal grass, paddle grass (H. decipiens), star grass, and widgeon grass (Fourqurean et al. 

2002). Turtle grass is often dominant in areas of stable salinity, stable sediments, and high light 

availability while shoal grass and manatee grass are more often found in slightly deeper or more 

frequently disturbed areas (Fourqurean et al. 2002). In contrast, Halophila species are generally 

restricted to low light environments (Fourqurean et al. 2002). Specific information on the current 

areal extent of seagrass species in south Florida is lacking (Fourqurean et al. 2002). Duarte 

(1991) found that seagrasses are capable of occupying areas from mean sea level down to a depth 

of 295 ft (90 m). 

Nutrient availability was also posited as a determining factor in turtle grass distribution 

(Fourqurean et al. 2002). 

Invertebrates: Lindeman et al. (2009) reported that over 533 species of invertebrates have been 

identified along the east Florida coast including sponges, polychaetes, echinoderms, crabs, and 

shrimp. The authors also found that disturbances to nearshore hardbottom habitat (found 

especially in the central and southern areas of the Atlantic coast) could affect the abundance of 

invertebrates (sponges, corals, crabs, shrimp, worms, gastropods, bivalves), which can alter the 

nearshore food web (Lindeman et al. 2009). Chronic turbidity along the coast could affect the 

fitness and survival of suspension feeders, and reduced visibility could affect predator-prey 

interactions (Lindeman et al. 2009). 

Oyster beds are located near the Halifax River and Tolomato-Matanzas estuaries to the north 

(FDEP 2010b). Oysters are typically regarded as a primary sensitive aquatic resource, though no 

functional relationship has been found between nutrient levels and oysters (FDEP 2010b, 2010c). 

Fish: Approximately 257 species of fish have been identified in nearshore hardbottom habitats 

along the central and southern Atlantic Coast (Lindeman et al. 2009). 

Dredge-and-fill activities resulted in burial of nearshore bottom habitat at Carlin Park (1.2 mi 

[2 km] south of Jupiter Inlet) which lowered the abundance of species and individuals (Lindeman 

and Snyder 1999). Fish populations have also been affected by phytoplankton blooms (Murphy 

et al. 1975). Atlantic Spadefish, common prior to the 2002 cyanobacterial bloom, were no longer 

present. The authors also suggest the decline of the local lobster fishery due to bloom impacts on 

mating and laying eggs (Tichenor 2003, 2004). 

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Reptiles and Amphibians: Nearshore hardbottom habitat off the central and southern Atlantic 

coast of Florida appears to provide intermediate life stage habitat for juvenile marine turtles, 

particularly green, loggerhead, and hawksbill turtles, whose residency is approximately 2 to 

5 years. Marine turtle species experience indirect effects from poor water quality due to impacts 

to their food resources (Lindeman et al. 2009). Food sources that could be affected include 

mollusks and crustaceans (key food sources for loggerheads), sponges (a common food source 

for hawksbills), and macroalgae (a primary food source for green turtles) (Lindeman et al. 2009). 

Birds and Mammals: The Florida Atlantic Coast is home to many species of birds. Species of 

pelagic birds found in the area include northern gannets, magnificent frigate birds, and jaegers 

(Space Coast Audubon Society 2001). Species found closer to shore include sanderlings, willets, 

red knots, ruddy turnstones, black-bellied plovers, piping plovers, laughing gulls, ring-billed 

gulls, herring gulls, great black-backed gulls, Caspian terns, royal terns, sandwich terns, common 

terns, Foster’s terns and least turns (Space Coast Audubon Society 2001). 

The Atlantic Coast is home to the West Indian manatee (Trichechus manatus). These large, slowmoving mammals feed primarily on seagrasses and many migrate between warmer areas during 

the winter (northern Biscayne Bay to Port Everglades, Florida) and cooler areas in the summer 

(lower [northern] St. Johns River to Brunswick, Georgia). A small percentage (12%) remains in 

one localized area year round (Deutsch et al. 2000). Humans represent the primary threat to 

manatee populations via direct effects, such as the hazards presented by watercraft collisions, 

and indirect effects, such as impacts to water quality and the effects of increasing coastal 

development (Deutsch et al. 2000). 

2.3. Status of Neighboring Estuarine Systems 

2.3.1. Northwest Panhandle 

There are several impairments in estuarine waters adjacent to the northwest Gulf Coast (USEPA 

2005). A complete list of Class II and Class III marine WBIDs listed for a nutrient-related 

parameter included on Florida’s CWA section 303(d) list approved by EPA in these estuarine 

systems are described in detail in Volume 1 of the TSD, Appendix A. Estuarine waters adjacent 

to the northwest Gulf Coast are usually described as having low turbidity and supporting healthy 

and relatively sizable seagrass coverage. Many of these areas also remain less heavily developed 

compared to other coastal areas in Florida, possibly attributed to the large abundance of state 

conservation land and managed aquatic preserves (Livingston 2001). There have been reports of 

increased stormwater runoff into the estuaries from coastal development and freshwater inputs. 

Climatic events increase freshwater input into areas such as Pensacola Bay, stimulating an 

increase in phytoplankton biomass (Hagy et al. 2006). 

A mass mortality of blacktip sharks (Carcharhinus limbatus) and Atlantic sharpnose sharks 

(Rhizoprionodon terraenovae) occurred in northwest Florida in October 2000 in conjunction 

with a red tide bloom of K. brevis. Flewelling et al. (2010) analyzed brevetoxin concentrations in 

the tissues of six sharpnose sharks and three blacktip sharks collected in the northwest Gulf 

Coast region during two red tides in October 2000 and September 2005. Brevetoxin 

concentrations ranging from 31 to 1,057 nanograms (ng) of Brevetoxin-3 (PbTx-3) equivalents 

per gram (g) of tissue were found in the muscles, liver, gill, kidney, brain, and gastrointestinal 

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tissues of the specimens collected. Cell counts of K. brevis collected in the water ranged between 

300,000 to 19,900,000 cells/L (Flewelling et al. 2010). 

Unusual mortalities of dolphins along the Florida Panhandle have coincided with K. brevis 

blooms. Between August 1999 and May 2000, the death of 152 dolphins was attributed to 

K. brevis (NOAA 2009). Later, between March 10 and April 13, 2004, 107 bottlenose dolphins 

and hundreds of fish and marine invertebrates were found dead along the Florida Panhandle. 

Analyses of the dolphin tissues found high levels of brevetoxin (Flewelling et al. 2005; NOAA 

2004). Between September 2005 and April 2006, 90 bottlenose dolphin strandings occurred 

along the Florida Panhandle, also associated with a K. brevis bloom, which occurred in 

September 2005. Brevetoxin was found in the tissues of the stranded dolphins (NOAA 2009). 

Vegetation damage from coastal development and storms can lead to an increase in future 

nutrient exports to coastal waters, which is an issue that is expected to worsen with the 

expanding coastal development. For example, the monitoring program in St. Joseph Bay 

recorded an increase in microalgae cover over the last several years that is associated with 

nutrient loadings from stormwater runoff. According to their water quality monitoring program, 

primarily focused on nutrients, there has been a slight increase in TN and TP in St. Joseph Bay 

between December 2000 and May 2006 (FDEP 2008). 

Major uses of the state preserves in the northwest are recreational fishing, boating, diving, 

swimming, and commercial navigation. Currently, these uses are being met in coastal waters, 

despite some evidence of nutrient pollution in the neighboring estuaries (FDEP 1991). The 

northwest coastal region contains many aquatic preserves and state conserved lands that extend 

3 mi (4.8 km) out from the coast, such as the Apalachicola Bay, St. Andrews Bay, and St. Joseph 

Bay state aquatic preserves, which are also designated as Outstanding Florida Water sites.2 As of 

July 1, 2011, all management activities, research, and monitoring in the Apalachicola, St. 

Andrews, and St. Joseph bays has ended due to state budgetary concerns (FDEP 2011). 

Given the current status of these estuaries and the relatively small amount of anthropogenic 

alteration in the northwest panhandle region compared to other regions in the state, a reference 

condition approach using recent data would appear to support designated uses. 

2.3.2. West Gulf Coast 

In contrast to the northwest, the estuarine regions adjacent to the west Gulf Coast display greater 

variation in water quality across several systems. These differences cause the applicability of a 

reference condition approach in coastal waters to vary according to more specific locations. 

Variable land uses and their proximity to surface waters cause differences among regions’ 

estuarine and coastal water quality (CHNEP 2009). 

The main source of nitrogen to nearshore coastal waters is from estuarine flux. Sampling 

between 1998 and 2001 showed extremely low nitrate (NO3) levels. Levels were slightly higher 

at the 82 ft (25 m) isobaths in 1998, which was an upwelling year (see Table A-2). Surface 

nitrate levels ranged from 0.0001 to 0.0022 mg/L as nitrogen (0.01 to 0.16 μM), while bottom 

levels ranged from 0.0004 to 0.0015 mg/L as nitrogen (0.03 to 0.11 μM) at 33 ft (10 m), 0.0003 to 

2 Section 62-302.700, F.A.C. 

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Table A-2. Average annual surface and bottom concentrations of phosphate and nitrate (as mg/L) at the 33, 82, 

and 164 ft (10, 25, and 50 m) isobaths (adapted from Vargo et al. 2008). Each value is the average of monthly 

measurements (±SD). 

Phosphate (mg/L as phosphorus) Nitrate (mg/L as nitrogen) 

33 ft (10 m) 82 ft (25 m) 164 ft (50 m) 33 ft (10 m) 82 ft (25 m) 164 ft (50 m) 

1998a Surface 

(SD) 

0.009 

(±0.005) 

0.001 

(±0.001) 

0.001 

(±0.002) 

0.0008 

(±0.001) 

0.0014 

(±0.0017) 

0.0018 

(±0.0029) 

Bottom 

(SD) 

0.010 

(±0.005) 

0.003 

(±0.004) 

0.007 

(±0.006) 

0.001 

(±0.0014) 

0.0077 

(±0.010) 

0.0385 

(±0.0496) 

1999 Surface 

(SD) 

0.007 

(±0.004) 

0.002 

(±0.000) 

0.001 

(±0.001) 

0.0006 

(±0.0008) 

0.0001 

(±0.0003) 

0.0001 

(±0.0003) 

Bottom 

(SD) 

0.007 

(±0.004) 

0.002 

(±0.001) 

0.003 

(±0.002) 

0.0004 

(±0.0006) 

0.0003 

(±0.0004) 

0.0014 

(±0.0027) 

2000 Surface 

(SD) 

0.005 

(±0.006) 

0.002 

(±0.004) 

0.001 

(±0.001) 

0.0022 

(±0.0071) 

0.001 

(±0.0022) 

0.0007 

(±0.001) 

Bottom 

(SD) 

0.004 

(±0.003) 

0.002 

(±0.001) 

0.002 

(±0.002) 

0.0015 

(±0.0048) 

0.0008 

(±0.0017) 

0.0027 

(±0.0031) 

2001a Surface 

(SD) 

0.003 

(±0.000) 

0.001 

(±0.001) 

0.001 

(±0.001) 

0.0018 

(±0.0042) 

0.0001 

(±0.0003) 

0.0001 

(±0.0004) 

Bottom 

(SD) 

0.004 

(±0.003) 

0.001 

(±0.001) 

0.005 

(±0.009) 

0.0014 

(±0.0035) 

0.0004 

(±0.0007) 

0.001 

(±0.0035) 

Note: ft = feet; L = liter; m = meter; SD = standard deviation a Values for these years consist of measurements made from June through December 

 

 

 

 

 

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0.0077 mg/L as nitrogen (0.02 to 0.55 μM) at 82 ft (25 m), and 0.001 to 0.0385 mg/L as nitrogen 

(0.08 to 2.75 μM) at 164 ft (50 m) (Vargo et al. 2008).3 

Under normal conditions approximately 24.0 kg/day dissolved inorganic nitrogen (DIN) 

(1.71 x 106 moles per day) are delivered to the west-central coast and estuaries through surface 

runoff (Hu et al. 2006). Another source of nitrogen is submarine groundwater discharges. The 

submarine groundwater discharges in Tampa Bay deliver almost 35 percent as much DIN as all of 

the rivers in north and central Florida that drain into the Gulf of Mexico combined (Hu et al. 2006). 

Under normal conditions approximately 26 kg/day (0.83 x 106 moles) dissolved inorganic 

phosphorus are delivered to the west-central coast and estuaries via surface runoff (Hu et al. 

2006). Phosphate (PO4) levels ranged from 0.001 to 0.009 mg/L as phosphorus (0.02 to 

0.29 μM) for surface waters between 1998 and 2001. For bottom waters, phosphate levels ranged 

from 0.004 to 0.010 mg/L as phosphorus (0.12 to 0.32 μM) at 33 ft (10 m), 0.001 to 0.003 mg/L 

as phosphorus (0.04 to 0.10 μM) at 82 ft (25 m), and 0.002 to 0.007 mg/L as phosphorus (0.08 to 

0.22 μM) at 164 ft (50 m) (Vargo et al. 2008).4 

A year-long red tide that started in January 2005 off of the west Gulf Coast in Tampa Bay, 

Charlotte Harbor, and Sarasota Bay, covered the entire inner shelf by September 2005. On 

December 28–29, 2004, the bloom was approximately 420 square miles (mi2) (1,100 square 

kilometers [km2]), and grew to 2,760 mi2 (7,140 km2) by January 21, 2005. Samples taken in 

January found high (105–106 cells/L) and very high (>106 cells/L) concentrations of K. brevis 

3 The authors reported concentrations in M (moles) or μM in the literature (in parentheses). 4 The authors reported concentrations in M (moles) or μM in the literature (in parentheses). 

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near the 100–130 ft (30–40 m) isobaths, and nil to low concentrations nearshore. The bloom 

caused hypoxic zones leading to extensive mortalities among the benthic communities, fish, 

turtles, birds, manatees, and other marine mammals (Hu et al. 2006). This area of the Gulf of 

Mexico has had numerous reports of blooms over the past 120 years, most caused by K. brevis. 

Increased freshwater discharge from the Shark River and other rivers along the southwest Florida 

coast is responsible for the increase in nutrients that enhance diatom growth and trigger summer 

to fall diatom blooms along the inner shelf (Jurado et al. 2007). For example, a study that 

examined dated sediment determined that an increase in phytoplankton pigments in areas around 

Charlotte Harbor signified an increase in diatom production and cyanobacterial populations over 

time (Turner et al. 2006). Turner et al. (2006) found that indicators of phytoplankton growth in 

sediment cores changed with the nitrogen loading to the watershed and suggested bloom 

occurrence has increased over time. These higher nitrogen loadings have been identified as a 

contributor to hypoxia and the growth of harmful blooms (Turner et al. 2006). Charlotte Harbor 

National Estuary Program found decreasing trends for chlorophyll a in the Tidal Caloosahatchee, 

Lower Charlotte Harbor, and Lemon Bay areas (CHNEP 2009). 

During the 1998‒2005 period, Upper Charlotte Harbor, Pine Island Sound, Estero Bay, and 

Lemon Bay exceeded the annual mean chlorophyll a threshold of 11 μg/L (Impaired Waters 

Rule, Section 62-303.353, F.A.C.) (Duffey et al. 2007). 

Given the state of impairment of neighboring estuaries, coastal segments in the southwest are 

expected to be more prone to nutrient impairment than the Florida Panhandle and Atlantic Coast 

regions. While it is evident that impairments for estuaries are not directly applicable to coastal 

waters, the bloom information and comparisons of annual mean chlorophyllRS a concentrations 

among regions support the contention that the southwest coast has the highest chlorophyll a 

concentrations and is more susceptible to bloom events compared to the Florida Panhandle and 

Atlantic Coast regions. Because monitoring information and data are lacking, the source of the 

blooms and the extent to which nutrients impair coastal waters adjacent to impaired estuaries 

remain unknown. There still is a general lack of monitoring information and data in coastal 

waters, causing the source of these blooms to be ambiguous. 

2.3.3. Atlantic Coast 

Reference conditions along Florida’s Atlantic Coast, with regard to nutrients, are not as 

thoroughly studied as inland and estuarine waters. Although nutrient related impacts have been 

specifically investigated in some regions such as the Southeast Florida Reef Tract, there is 

generally very little information on nutrient pollution in the greater coastal areas. For some of 

Florida’s Atlantic coastal waters it can be difficult to directly assess the impact of nutrient 

pollution on designated uses. In areas where site-specific information regarding nutrient 

concentrations and related impacts is not available, an assessment of inflowing waters is 

provided. 

Information concerning nutrient impairment of coastal waters varies along Florida’s Atlantic 

Coast. In the northeast, there is a paucity of information concerning nutrient pollution. In the 

southeast, impairments are more thoroughly documented in coastal waters. 

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Northeast 

A complete list of Class II and Class III marine WBIDs listed for a nutrient-related parameter on 

Florida’s CWA section 303(d) list approved by EPA in this region can be found in Volume 1 of 

the TSD, Appendix A. 

Several studies have documented possible nutrient related impacts in streams and estuaries along 

the northeast coast and suggested that water quality has worsened over time. For example, 

DeVivo et al. (2009) found that DO and clarity in the Nassau River were good overall and 

chlorophyll a levels were considered fair, based on the East/Gulf Coast criteria outlined in EPA’s 

National Coastal Assessment II Report (USEPA 2005). A recent sampling effort by FDEP 

(2010a) showed that 20 percent of rivers and 87 percent of streams sampled in the NassauSt. Marys watershed were below the state DO threshold of 5 mg/L. Similarly, Mosquito Lagoon, 

a portion of Indian River Lagoon, was initially ranked as good after the 2007 EPA water quality 

assessment, but more recently, increases in chlorophyll a concentrations have been observed 

(FDEP 2006; USEPA 2007). Northeastern Florida is predicted to experience intense population 

growth and development, which has the potential to cause nutrient related impacts to worsen 

(FHDC 2011; Haydt and Frazel 2003). 

Barile (2004) reported the first annual record of inorganic nitrogen and phosphorus 

concentrations in the littoral area of the barrier island system adjacent to Brevard and Indian 

River counties. Concentrations of SRP ranged from 0.004 to 0.015 mg/L as phosphorus (0.13 to 

0.50 μM) with a mean of 0.008 mg/L as phosphorus (0.25 μM). SRP measurements taken after 

rains in March and December at the Wabasso-Ambersand Beach site (which is down-gradient 

from residential homes with septic tanks) were significantly higher and almost double (0.013– 

0.015 mg/L as phosphorus [0.42–0.50 μM]) the mean SRP values (Barile 2004). Nitrogenphosphorus ratios of water column inorganic nutrients for the littoral waters of the barrier islands 

adjacent to Brevard and Indian River counties were significantly lower (8:1) than the Redfield 

ratios for balanced growth of phytoplankton (16:1) and marine macrophytes (approximately 

30:1). Ambient inorganic phosphorus concentrations were found to be elevated with respect to 

bioavailable inorganic nitrogen concentrations. The ambient mean DIN for all sites and seasons 

was 0.0294 mg/L as nitrogen (2.10 μM), which is higher than the reported approximately 

0.014 mg/L as nitrogen (1.0 μM) threshold to support and saturate growth of K. brevis, the 

dominant red tide organism (Barile 2004).5 

3. Summary of Regional Trends 

Harmful Algal Blooms: Parts of all coastal regions in Florida have experienced a rise in the 

frequency and duration of HABs. In general, nutrient pollution from developed coastal habitats 

has led to increasing blooms in Florida coastal areas. Both the northwest and the southwest 

coastal regions have been impacted by cyanobacterial HABs from 2000 to 2009, leading to cases 

of neurotoxic shellfish poisoning. Coastal studies confirm both nitrogen and phosphorus inputs 

need to be controlled when non-nitrogen fixing HABs (such as K. brevis) occur with nitrogen 

fixing cyanobacterial species (Paerl et al. 2009). Cyanotoxins have been noted to invade surface 

drinking water supplies, kill seagrasses, and close recreationally valuable areas along the Gulf 

Coast (Paerl et al. 2009). 

5 The authors reported concentrations in M (moles) or μM in the literature (in parentheses). 

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Technical Support Document for U.S. EPA’s Proposed Rule for Numeric Nutrient Criteria, 

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Bloom frequency, duration, and intensity in Florida’s southwest region has increased over time 

(Burns 2008; Thomas and Rumbold 2006). Nitrogen and phosphorus pollution causes increased 

growth and productivity of Lyngbya, a species of cyanobacteria or blue-green algae, resulting in 

the degradation of coastal aquatic ecosystems. Trends and reports by Paerl et al. (2008) and 

Sharp et al. (2009) confirm that the introduction of nutrients into marine environments can 

increase the prevalence of HABs. Lyngbya blooms have been linked to both human health and 

ecological concerns, such as smothered corals and seagrasses (Burns 2008; Paerl et al. 2008). 

Several studies examined the diversity, distribution, and abundance of Lyngbya off nearshore 

waters in south Florida areas, including Tampa Bay and Sanibel Island, and the Atlantic Coast 

(Arthur et al. 2009; Paerl et al. 2008; Sharp et al. 2009). Persistent blooms were detected in the 

Indian River Lagoon and off Sanibel Island. On Sanibel Island, Lyngbya had a great impact on 

seagrasses by overgrowing shoots and smothering benthic organisms (Paerl et al. 2009). The 

results of a bioassay study demonstrated that primary production of Lyngbya significantly 

increased when chelated iron chloride and chelated iron chloride with nitrogen and phosphorus 

were added over four days (Arthur et al. 2009). These blooms negatively impact designated uses; 

tufts of Lyngbya float to the surface, becoming mats with malodorous, toxic properties that float 

onto beaches. Blooms of Lyngbya are associated with nutrient inputs from development and 

recreational activities, and nutrients in groundwater (Paerl et al. 2009). Less is known about the 

frequency of these blooms over time, as studies are more recent and there is currently no state 

monitoring program for HABs. While it is evident that these blooms exist off the coastal regions 

identified by EPA, there is a lack of information to determine any change in their occurrence 

over time with respect to nutrient pollution. 

The Gulf of Mexico Alliance developed water quality priorities to ensure healthy beaches and 

safe seafood along the entire Gulf Coast. The organization aims to reduce the risk of HABs by 

improving the “ability to detect, track, forecast, and mitigate HAB movement and their effects 

along the Gulf Coast.” The Gulf of Mexico Alliance also aims to improve monitoring efforts to 

support management decisions (GOMA 2011b). To address nutrient problems, the Gulf of 

Mexico Alliance is implementing regional nutrient characterization studies to evaluate the 

response of an ecosystem to nutrients. They will also support nutrient criteria development and 

nutrient reduction strategies (GOMA 2011a). 

ChlorophyllRS a: EPA collected data for all of the coastal regions in which criteria will be 

derived by satellite. After analysis of the data, EPA observed a lack of an upward trend in 

chlorophyllRS a in the 1998–2009 data set used to derive criteria (Figure A-7). Because there has 

been no observed trend of a continuous increase in chlorophyllRS a concentrations over this 

reference period, reference conditions based on recent data appear to be reflective of water 

quality that supports designated uses. Despite several instances of bloom conditions, it still 

appears chlorophyllRS a concentrations in these coastal regions have stayed approximately 

constant over time, if not slightly declining in more recent years. 

A-18 
 

 

 

5 

4.5
 

4
 

3.5
 

3
 Southwest 

Coast 

2.5 Northwest 

Coast 

2 

Atlantic Coast 

1.5
 

1
 

0.5
 

0
 

Geometric Mean for ChlorophyllRS (mg m-3 ) 

1998 1999 2000 2001 2002 2003 2004 2005 2006 2007 2008 2009 

Technical Support Document for U.S. EPA’s Proposed Rule for Numeric Nutrient Criteria, 

Volume 2 Coastal Waters 

Figure A-7. 1998-2009 chlorophyllRS a values (mg/m3

) for Florida’s three defined coastal regions 

4. References 

Alexander, J.E., T.T. White, K.E. Turgeon, and A.W. Blizzard. 1977. Baseline Monitoring 

Studies, Mississippi, Alabama, Florida Outer Continental Shelf, 1975–1976 Volume III: 

Results. BLM-ST-78-30. State University System of Florida Institute of Oceanography. 

http://www.gomr.boemre.gov/PI/PDFImages/ESPIS/3/4092.pdf. Accessed August 2011. 

Arnold, W.S., D.C. Marelli, C.P. Bray, and M.M. Harrison. 1998. Recruitment of bay scallops 

Argopecten irradians in Floridan Gulf of Mexico waters: Scales of coherence. Marine 

Ecology Progress Series 170:143-157. 

Arthur, K.E., V.J. Paul, H.W. Paerl, J.M. O’Neil, J. Joyner, T. Meickle. 2009. Effects of nutrient 

enrichment of cyanobacteriam Lyngbya sp. on growth, secondary metabolite 

concentration and feeing by the specialist grazer Stylocheilus striatus. Marine Ecology 

Progress Series 394:101–110. 

Barile, P.J. 2004. Evidence of anthropogenic nitrogen enrichment of the littoral waters of east 

central Florida. Journal of Coastal Research 20(4):1237-1245. 

Burns, J. 2008. Toxic cyanobacteria in Florida waters. Advances in Experimental Medicine and 

Biology 619:127–137. 

http://www.epa.gov/cyano_habs_symposium/monograph/Ch05.pdf. Accessed December 

2011. 

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Carr, G.B., P.A. Davis, R.E. Fergen, and F. Bloetscher. 2000. Water quality impacts of long-term 

effluent disposal strategies in Southeast Florida. Water-Engineering & Management 

147(5):49-53. 

CHNEP. 2009.Comparison of Water Quality Results from Fixed Station and Random Sampling 

Monitoring Programs in the Charlotte Harbor and Estero Bay Aquatic Preserves: 2001– 

2007. Charlotte Harbor National Estuary Program. Fort Meyers, FL. 

Choctawhatchee Audubon Society. No date. Birding Sites Okaloosa County, Northwest Florida. 

Choctawhatchee Audubon Society. 

http://www.choctawhatcheeaudubon.org/Birding_Map.pdf. Accessed August 2011. 

Collier, C., R. Ruzicka, K. Banks, L. Barbieri, J. Beal, D. Bingham, J. Bohnsack, S. Brooke, 

N. Craig, R. Dodge, L. Fisher, N. Gadbois, D. Gilliam, L. Gregg, T. Kellison, 

V. Kosmynin, B. Lapointe, E. McDevitt, J. Phipps, N. Poulos, J. Proni, P. Quinn, 

B. Riegl, R. Spieler, J. Walczak, B. Walker, and D. Warrick. 2008. The state of coral reef 

ecosystems of southeast Florida. In The State of Coral Reef Ecosystems of the United 

States and Pacific Freely Associated States: 2008. National Oceanic and Atmospheric 

Administration. 

http://ccma.nos.noaa.gov/ecosystems/coralreef/coral2008/pdf/FloridaSE.pdf. Accessed 

June 2011. 

Dames & Moore. 1979. Final Report: Mississippi, Alabama, Florida Outer Continental Shelf 

Baseline Environmental Survey. MAFLA, 1977/78. Prepared for U.S. Department of the 

Interior, Bureau of Land Management. Contract AA550-CT7-34. Dames & Moore. New 

Orleans, LA. http://invertebrates.si.edu/boem/reports/MAFLA_vol2.pdf. Accessed 

August 2011. 

Davis, R.A., K.E. Yale, J.M. Pekala, and M.V. Hamilton. 2003. Barrier island stratigraphy and 

Holocene history of west-central Florida. Marine Geology 200:103-123. 

Dawes, C.J. 1985. Seagrass community at Anclote Key. In Geology of the Barrier Island and 

Marsh-dominated Coast, West-Central Florida: Field Trip Guidebook for 1985 Annual 

Meeting, Geological Society of America, ed. R.A. Davis, A.C. Hine, and D.F. Belknap. 

Geological Society of America, Tampa, FL. 

Deutsch, C.J., J.P. Reid, R.K. Bonde, D.E. Easton, H.I. Kochman, and T.J. O’Shea. 2000. 

Seasonal Movements, Migratory Behavior, and Site Fidelity of West Indian Manatees 

along the Atlantic Coast of the United States as Determined by Radio-telemetry. Final 

Report. Florida Cooperative Fish and Wildlife Research Unit, U.S. Geological Survey 

and University of Florida. Gainesville, FL. 

http://aquaticcommons.org/1067/1/OCRDeutsch,_C.J._2000(2).pdf. Accessed August 

2011. 

DeVivo, J.C., P.H. Flournoy, and K.A. Smith. 2009. Assessment of Coastal Water Quality at 

Timucuan Ecological and Historic Preserve. Natural Resource Report 

NPS/SECN/NRR—2009/108. National Park Service, Fort Collins, CO. 

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Duarte, C.M. 1991. Seagrass depth limits. Aquatic Botany 40(4):363-377. 

Duffey. R,R.E. Leary, and J Ott. Sept, 2007. Charlotte Harbor and Estero Bay Aquatic 

Preserves: Water Quality Status and Trends for 1998-2005. Charlotte Harbor National 

Estuary Program, Fort Meyers, FL. 

FDEP. 1991. St. Andrews State Park Aquatic Preserve Management Program. Florida 

Department of Environmental Protection, Resources Department. 

FDEP. 2005. Water Quality Status Report: Upper East Coast. Florida Department of 

Environmental Protection. Florida Department of Environmental Protection, Tallahassee, 

FL. http://tlhdwf2.dep.state.fl.us/basin411/uppereast/status/UEC.pdf. Accessed August 

2011. 

FDEP. 2006. Water Quality Status Report: Indian River Lagoon. Florida Department of 

Environmental Protection. 

http://tlhdwf2.dep.state.fl.us/basin411/indianriver/status/IRL.pdf. Accessed July 2011. 

FDEP. 2008. St. Joseph Bay Aquatic Preserve: Management Plan. Florida Department of 

Environmental Protection. Tallahassee, FL. 

http://www.dep.state.fl.us/coastal/sites/stjoseph/pub/StJosephBay_2008.pdf. Accessed 

July 2011. 

FDEP. 2010a. Nassau-St. Marys Basin Lakes, Rivers, Streams, and Aquifers. Florida Department 

of Environmental Protection 

http://www.dep.state.fl.us/water/monitoring/docs/bmr/nassau_stmary.pdf. Accessed 

August 2011. 

FDEP. 2010b. Draft Site-Specific Information in Support of Establishing Numeric Nutrient 

Criteria in the Halifax River Estuary. Florida Department of Environmental Protection. 

Tallahassee, FL. 

http://publicfiles.dep.state.fl.us/dear/sas/nutrient/estuarine/bunnell/halifax_estuary_08231 

0.pdf. Accessed March 2011. 

FDEP. 2010c. Draft Site-Specific Information in Support of Establishing Numeric Nutrient Criteria 

in the Tolomato-Matanzas Estuary. Florida Department of Environmental Protection. 

http://publicfiles.dep.state.fl.us/dear/sas/nutrient/estuarine/bunnell/tolomato_matanzas_es 

tuary.pdf. Accessed May 2011. 

FDEP. 2011. CAMA Office Closures. Florida Department of Environmental Protection. 

http://www.dep.state.fl.us/coastal/office_closures.htm. Accessed August 2011. 

FHDC. 2011. Population Projection by Age for 1990-2030: Results for St. Johns and Flagler 

Counties. Florida Housing Data Clearinghouse. 

http://flhousingdata.shimberg.ufl.edu/a/population. Accessed July 2011. 

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Flewelling, L.J., D.H. Adams, J.P. Naar, K.E. Atwood, A.A. Granholm, S.N. O'Dea, and J.H. 

Landsberg. 2010. Brevetoxins in sharks and rays (Chondrichthyes, Elasmobranchii) from 

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