855-R-04-001
Cover Image:

Small Photo: Extensive seagrass damage as a result of propeller scarring and boat

wake from recreational boating in East Flats, Texas. Photo provided by Bill Harvey,

Texas Parks and Wildlife Department.

Large Photo: Undisturbed seagrass habitat in the northern Gulf of Mexico. Photo

provided by South Florida Water Management District.

The Gulf of Mexico Program (GMP) is a network of citizens dedicated to

managing and protecting the resources of the Gulf of Mexico in ways consistent

with the economic well-being of the region. Administered by the U.S.

Environmental Protection Agency (USEPA), the GMP engages many organizations

across the Gulf for leadership on four ecological issues across the Gulf

watersheds: (1) public health, (2) excess nutrient enrichment, (3) habitat

degradation and loss, and (4) introduction of nonindigenous species. The GMP

includes representatives from state and Federal agencies, non-profit

organizations, the scientific community, business and industry, and an organized

citizens group whose members are individually appointed by the governors of the

five Gulf States (Texas, Louisiana, Mississippi, Alabama and Florida).

The GMP has long recognized estuaries and coastal wetlands as vital to

providing food and shelter for certain plants and animals, improving water

quality, providing sediment filtration and flood and erosion control. In 1999, the

GMP’s Habitat Team set a goal to restore, enhance, or protect 20,000 acres of

important coastal and marine habitats in U.S. areas of the Gulf by 2009. The

GMP Habitat Team also developed several objectives to support this goal,

including the production of an updated Seagrass Status and Trends Report. The

purpose of this report is to provide scientists, managers, and citizens with

valuable baseline information on the status of seagrasses in coastal waters of

the Gulf of Mexico, and to increase awareness that the seagrasses of the Gulf

are of global significance.

To produce this report, the GMP’s Habitat Team formed a Seagrass

Subcommittee consisting of scientists and environmental managers along the

Gulf Coast. This committee provided valuable information regarding the latest

seagrass maps, seagrass status and trends, causes of change and current

monitoring, restoration, and enhancement activities important to their area.
Table of Contents

Gulf of Mexico Overview ......................................................................................... 5

What are Seagrasses? ............................................................................................. 6

Seagrass Species in the Northern Gulf of Mexico ................................................... 7

Why are Seagrasses Important?.............................................................................. 10

Seagrass Habitats .................................................................................................. 10

Value of Seagrasses .............................................................................................. 11

Seagrass Degradation and Loss .............................................................................. 13

Causes of Degradation ........................................................................................... 14

What is the Status of Seagrasses in the Northern Gulf of Mexico?....................... 16

Overview of Seagrass Habitat in the Gulf.......................................................... 16

Seagrass Habitat in My Area .............................................................................. 18

Texas ............................................................................................................... 18

..... Laguna Madre, Coastal Bend, Galveston Bay

Central Northern Gulf Region ........................................................................... 19

..... Chandeleur Islands, Mississippi Sound, Mobile Bay, Perdido Bay

Northwestern Florida ....................................................................................... 20

..... Pensacola Bay, Choctawhatchee Bay, St. Andrew Bay, Big Bend

Southwestern Florida ...................................................................................... 21

..... Tampa Bay and St. Josephs Sound, Sarasota Bay,

..... Charlotte Harbor Estuary, Florida Bay

How Are We Improving Damaged Seagrass Habitat? ............................................ 23

Management Practices .......................................................................................... 23

Monitoring and Restoration .................................................................................... 24

What does the Future Hold for Seagrasses? ........................................................... 25

Literature Cited ......................................................................................................... 26
Gulf of Mexico. Source: SeaWiFS Project, NASA/Goddard Space Flight Center, and ORBIMAGE
Gulf of Mexico Overview

The Gulf of Mexico is a partially landlocked sea that lies in the southeastern quadrant of the North American continent. Mexico and the United States form a continuous shoreline around the majority of the Gulf

that extends over 2,500 miles in distance (Britton & Martin, 1989). An arbitrary boundary between northeastern Yucatan and the southern tip of Florida defines the southern boundary and separates the Gulf of

Mexico and Caribbean Sea.

For the purposes of reporting the status and trends of seagrasses in the United States, the study area is

defined as the waters of the Gulf that lie adjacent to five Gulf States: Texas, Louisiana, Mississippi, Alabama, and Florida, also known as the “Northern Gulf Region.” This boundary spans a distance of approximately 1,500 miles, with significant additional shoreline enclosed behind barrier islands or estuarine

embayments along the coast. The southwestern boundary of the Northern Gulf Region begins near

Brownsville, Texas and spans clockwise, terminating at the eastern most reaches of Florida Bay, which

includes the northern boundary of the Florida Keys and Dry Tortugas.

Ecologically, the region is a rich and productive subtropical environment that supports extensive wetland

and seagrass habitats (Beck et al, 2000). In 1997, the estimated commercial value of harvested finfish and

shellfish from the Gulf was $823 million (NOAA, 1997). Geologically, the region consists of low sandy

banks or marshlands that characterize the northern temperate and subtropical gulf shores, with extensive

barrier islands, salt marshes, and mangroves present (Britton & Martin, 1989). The shores of the most

northern reaches of the Gulf occur in temperate regions and are a product of sedimentary processes

influenced by several rivers including the Trinity, Mississippi, Mobile-Tensaw and Apalachicola Rivers. The

southern reaches of Florida and Texas experience more tropical climatic conditions, where rainfall and

riverine influence are reduced, and clear-water habitats prevail.

The Gulf of Mexico is a dynamic system that has evolved over great lengths of time. However, recent

declines in seagrass abundance have impacted the environmental quality of local estuaries, mangroves,

and coastal areas. Changes to seagrass habitat can occur over short time periods such as weeks or even

days. For example, alteration can be induced by tropical hurricanes, many of which form in the southern

Atlantic and move through the Gulf of Mexico. Fortunately, the effects of these destructive events are

short-lived and the system usually recovers naturally. Other impacts may be cumulative, such as those

caused by anthropogenic sources, and may require remedial action and much longer time periods for

recovery.

Gulf of Mexico Overview
What are Seagrasses?

Seagrasses are submerged flowering plants growing in bays, lagoons, and shallow

coastal waters. Similar to terrestrial vegetation, seagrasses have leaves, stems,

flowers, seeds and roots, using the process of photosynthesis to produce food and

oxygen. Because seagrasses require light for photosynthesis, good water quality is

very important for seagrass survival.

Seagrasses anchor themselves to the seafloor with their root systems. A strong

root structure allows seagrasses to withstand strong currents and waves, especially during storm events. Seagrasses differ from their land-based counterparts in

that they must reproduce underwater. They accomplish this by producing filamentous pollen grains that can be transported by water currents. Another means of

propagation is by the use of underground storage organs called rhizomes. By

spreading underground, the seagrass system expands and facilitates vegetative

reproduction.

Seagrasses are able to tolerate a wide range of climates, located as far north as

Alaska and as far south as the equator in the northern hemisphere. They can

withstand temperatures as low as negative 6 degrees Celsius to readings as high

as 40.5 degrees Celsius (Phillips & Meñez, 1988). Seagrasses can grow in salinities that range from freshwater to 42 parts per thousand (ppt). However, seagrass

has tolerated 50 ppt in Laguna Madre and Florida Bay. The most vibrant stands

are normally found occurring in environments between 10 to 30 ppt (Phillips &

Meñez, 1988).

6 SEAGRASS HABITAT IN THE GULF OF MEXICO: Degradation, Conservation and Restoration of a Valuable Resource
Seagrass Species in the Northern

Gulf of Mexico

A total of 58 species of seagrasses can be found around the world, consisting

of two main families (Phillips & Meñez, 1988; Kuo & McComb, 1989). Short &

Coles (2001) state that recent work establishes that there are 60 seagrass

species in 4 families and 12 genera. In the Northern Gulf Region, 6 species of

seagrass are common. Below is a listing of common species, including family,

species, and common name found in the Gulf of Mexico.

Family Species Common Name

Hydrocharitaceae Halophila decipiens paddle grass

Hydrocharitaceae Halophila engelmannii star grass

Hydrocharitaceae Thalassia testudinum turtle grass

Potamogetonaceae Halodule wrightii shoal grass

Potamogetonaceae Syringodium filiforme manatee grass

Potamogetonaceae Ruppia maritima wigeon grass

Due to the diversity of climates in the region, a wide variety of seagrasses are

present in the Northern Gulf Region. Some seagrasses adapt better to the

more tropical conditions of southern Texas and Florida, while others fare better

in the more temperate conditions of the north. The following section provides

a brief description of each of the 6 species found in the Gulf and their

respective biological and ecological characteristics (Phillips & Meñez, 1988;

Fonseca, 1994).

Paddle Grass (Halophila decipiens)

Physical Characteristics – Paddle grass is a small species that normally stands

3 to 5 centimeters (cm) tall. Oval blades occur in pairs and are very thin,

appearing translucent to the eye. Rhizomes are often located near the surface

and are often exposed to the water column.

Habitat Preferences – Due to a shallow rhizome structure, paddle grass is

easily uprooted, and therefore, typically grows at depths between 10 and 30

meters (m). Halophila decipiens requires less light than other seagrasses and

can be found in turbid areas, below docks, or at depths of up to 40 m in clear

tropical waters.

 S E A G R A S S H A B I T A T I N T H E G U L F O F M E X I C O : Degradation, Conservation and Restoration of a Valuable Resource 7
Distribution – This pantropical species is found

mostly in the warmer water of the Northern Gulf

Region. Extensive acreage of seasonal beds have

been observed in southern Florida.

Star Grass (Halophila engelmannii)

Physical Characteristics – Star grass, also a

member of the Halophila genus, has many similar

physical characteristics to paddle grass. A very

small plant Halophila engelmanni rarely exceeds 10

cm in height.

Habitat Description – Halophila engelmannii can be

found in sheltered sites from low-spring tide level

up to 90 m in clear waters. Its habitat is generally

in sandy and muddy substrates, but it can also be

found in areas with gravel or rock bottom.

Distribution – Plants are distributed similarly to

paddle grass, being widely distributed in the

Northern Gulf Region near Florida, but are also

present along the Chandeleur Islands, located

southeast of Louisiana.

Turtle Grass (Thalassia testudinum)

Physical Characteristics – This species’ common

name comes from it being a favorite food of the

endangered green sea turtle. Turtle grass has

broad, deep-green blades that are normally over 1

cm wide and range from 10 to 75 cm long. The

thick rhizomes are often located at depths of 20 cm

below the surface.

Habitat

Description –

Thalassia

testudinum is

often found from

just below the

low tide surface

to depths of 30

m in clearer

waters. This

plant generally

prefers mud or

sand substrate

Star grass. Source: Phillips & Meñez, 1988.

Paddle grass. Source: Phillips & Meñez, 1988.

Turtle grass. Source: Phillips & Meñez, 1988.

8 SEAGRASS HABITAT IN THE GULF OF MEXICO: Degradation, Conservation and Restoration of a Valuable Resource
for colonization.

Distribution – Turtle grass can be found in dense,

extensive stands, throughout the Northern Gulf

Region. Individual shoots of the plant can live for

over 10 years, enduring seasonal temperature

changes and powerful tropical storms.

Shoal Grass (Halodule wrightii)

Physical Characteristics – Shoal grass has fine

blades that are 1 to 3 millimeters (mm) in width

that grow to between 5 and 40 cm in length.

Rhizomes are located close to the surface, often

found less

than 5 cm

below the sea

floor. However, roots

may be found

as deep as 25

cm below the

sea floor.

Habitat

Description –

Halodule

wrightii is found in lower-intertidal and uppersubtidal zones as deep as 12 m. Large continuous

meadows on shallow shoals and flats are predominant, with the grass often exposed at times of low

tide. Sandy and muddy substrates are the most

common habitat for shoal grass, but can also be

found on coral reefs and in mangrove swamps.

Distribution – Shoal grass is widely dispersed

throughout the Northern Gulf of Mexico, having

significant populations in most bays and estuaries.

Manatee Grass (Syringodium filiforme)

Physical Characteristics – Manatee grass is distinguished by its nearly cylindrical appearance. Long,

straight blades are approximately 1 to 3 mm in

diameter and can grow up to 40 cm long. Rhizomes

are located at depths between 1 and 10 cm below

Manatee grass.

Source: Phillips &

Meñez, 1988.

Shoal grass.

Source: Phillips & Meñez,

1988.

the sea floor, but

may also extend into

the water column,

presumably as a

means of vegetative

reproduction.

Habitat Description –

Syringodium filiforme is

found mostly in subtidal

environments.

Macroalgae may accumulate into a large understory beneath

Syringodium. Often these beds are mixed with

turtle grass, but large monospecific stands may

form down to 18 m.

Distribution – Manatee grass is found on a limited

basis in the Northern Gulf of Mexico, and becomes

more widespread in South Texas and Florida.

Wigeon Grass (Ruppia maritima)

Physical Characteristics – Wigeon Grass is a

submerged aquatic vascular plant considered by

many to be a seagrass although it can grow in both

freshwater and saline environments. Blades are

0.5 mm wide and 3 to 10 cm tall. A favorite food

of migratory waterfowl, wigeon grass does not

form a thick rhizome mat as compared to other

seagrass species such as turtle grass.

Habitat Description – Ruppia maritima grows in soft

sediments in sheltered shallow coastal waters of

estuaries and lagoons at depths of 1 to 3 m.

Distribution – Wigeon grass is the most common

submerged aquatic vascular plant in the parts of

the Gulf estuaries most influenced by fresh water.

 S E A G R A S S H A B I T AT I N T H E G U L F O F M E X I C O : Degradation, Conservation and Restoration of a Valuable Resource 9
Seagrass beds can be considered one of the foundations of coastal and estuarine

ecosystems in the Northern Gulf Region. These highly productive marine plant

communities provide valuable habitat in the waters that they populate. Continuous

seagrass beds stabilize coastal sediments, decrease wave energy, and provide

shelter for a variety of juvenile and adult aquatic species. In addition, seagrass

beds support important recreational and commercial fisheries critical to the

economic and social well-being of the region.

Seagrass Habitats

A multitude of plants and animals inhabit seagrass ecosystems forming complex

food webs linking a variety of species together. The major functions of seagrasses

in supporting both aquatic and terrestrial species include food production, nutrient

recycling, and refuge from predation. The following lists the major species found in

seagrass habitats, describes their relationship to the system, and elaborates on

their role in the Northern Gulf ecological community (Japp & Hallock, 1990).

Mammals and Reptiles

Large species, such as manatees (Trichecus manatus), green sea turtles (Chelonia

mydas), and bottlenose dolphins (Tursiops truncatus), are found in seagrass beds

throughout the Northern Gulf Region. Manatees and green sea turtles feed directly

on seagrasses, while bottlenose dolphins capture smaller species associated with

the ecosystem. Because of these feeding relationships, all these species are

affected by the loss or degradation of seagrass habitat.

Why are Seagrasses Important?

10 SEAGRASS HABITAT IN THE GULF OF MEXICO: Degradation, Conservation and Restoration of a Valuable Resource
Fish

Finfish species utilizing seagrass habitat include

drums (Sciaenidae), sea bass (Serranidae), porgies

(Sparidae), grunts (Haemulidae), snappers

(Lutjanidae) and mojarras (Gerreidae). Seagrass

habitat is used as nursery area by juveniles of

larger species. Smaller species use the cover as

protection from predation. Several of the larger

finfish are recreationally and commercially

important to the Northern Gulf Region.

Shellfish

Examples of shellfish utilizing seagrass habitat are

the spiny lobster (Panulirus argus), queen conch

(Strombus gigas), West Indian sea star (Oreaster

reticulata), pink shrimp (Farfantepenaeus), and bay

scallops (Argopecten irradians). The majority of

these species dwell at the base of the seagrass

beds, while others, such as the spiny lobster, come

from nearby locations to feed at night.

Birds

Birds inhabiting seagrass areas include wading and

diving birds, such as mergansers (Mergus

merganser), loons (Gavia immer), cormorants

(Phalacrocorax carbo), pelicans (Pelecanus

occidentalis) and redhead ducks (Aythya

americana). Most birds use seagrass areas as

regular feeding grounds, consuming seagrass

blades and rhizomes or fish swimming within the

grasses. Other species temporarily inhabit the

ecosystem as they make their seasonal

migrations along the coast.

Value of Seagrasses

Seagrasses contribute significant value to the

Northern Gulf Region. While there is no single

estimate of the value of seagrasses in the region,

there are several attributes that demonstrate the

importance of the habitat to both the aquatic

ecosystem and to the local economy. Finfish and

shellfish use the beds as habitat for rearing juveniles and feeding as adults. Seagrass beds improve water quality by adding oxygen to the water

column. They baffle sediments, reducing adverse

effects from waves and currents. Seagrasses

provide sediment stabilization, reduce coastal

erosion, and filter nutrients and contaminants from

the water. Economically, recreational fishing for

finfish and shellfish supported by seagrass habitat

increases tourism, which benefits the local

economy.

It is estimated that between 70 percent to 90

percent of commercial fish spend some part of

their life in seagrass habitat (FDEP, 2001). A wide

variety of fish harvested in the region use

seagrasses for rearing and feeding during their life

stages. Snappers, sea bass, shrimp, crabs, and

oysters are among the many species contributing

to the overall value of commercial fishing.

 S E A G R A S S H A B I T AT I N T H E G U L F O F M E X I C O : Degradation, Conservation and Restoration of a Valuable Resource 11
The total commercial fish landings of the Northern Gulf Region totaled over

1.7 billion pounds in 2002, accounting for nearly $705 million in revenues

(NMFS, 2003).

Recreational fishing is also a very important source of revenue for the

Northern Gulf Region with both in- and out-of-state anglers contributing to

local economies. Species such as bonefish, tarpon, and spotted seatrout

support a multimillion dollar recreational fishery that derives its income

from charter boats, marinas, hotels, restaurants, and tackle shops (FDEP,

2001). Many recreational fish species spend their juvenile years in

seagrass meadows, migrating offshore in the adult years.

Tourism is another significant economic attribute of seagrass habitat.

Direct benefits are observed when residents and non-residents take ecotourism trips to seagrass meadows. Non-residents spend hundreds of

millions of dollars annually at hotels, restaurants, and outdoor outfitting

shops along the coast (FDEP, 2001). In addition, discarded shells of over

30 species of bivalves are actively collected by tourists and commercial

retailers. One example of the economic value of seagrasses is from the

Texas Parks and Wildlife Department (TPWD 1999). This agency

estimates that based on the current account of seagrass distribution,

recreational value, and commercial fishery harvest that wetland habitats

contribute approximately 12.6 million dollars annually to regional

economies. It is important to protect this valuable resource by utilizing

effective conservation methods.

12 SEAGRASS HABITAT IN THE GULF OF MEXICO: Degradation, Conservation and Restoration of a Valuable Resource
Two major disturbances affect seagrass growth, health, and survival in the

Northern Gulf Region. Natural perturbations such as storms can increase wind

and wave action, causing increased turbidity and erosion that damage seagrass

beds. Other meteorological events, including floods, droughts, and hurricanes, all

have detrimental effects on the short-term health of the ecosystem. However,

seagrass beds usually rebound from the effects of these natural events, or slowly

shift to a new equilibrium with their surroundings.

Alternatively, anthropogenic, or human induced impacts, can have much more

severe and long-lasting negative effects on seagrass beds. Because seagrasses

rely heavily on light for photosynthesis, any action decreasing water quality in the

marine environment can harm seagrass plants. In addition, increases in nutrients

can cause (1) macroalgae to “overgrow” seagrass; and (2) microalgae (phytoplankton) blooms that reduce water clarity. Finally, impacts directly damaging

seagrass beds, such as scarring from boat propellers or trawl nets can have

cumulative impacts on the ecosystem.

Propeller scarring of seagrass beds from boating. Source: Penny Hall, Florida Marine Research Institute

 S E A G R A S S H A B I T A T I N T H E G U L F O F M E X I C O : Degradation, Conservation and Restoration of a Valuable Resource 13

Seagrass Degradation and Loss
Causes of Degradation

Nutrient Loading Effects

Eutrophication due to nutrient loading is a leading

cause of degradation to seagrass habitats in the

Northern Gulf Region. There are several sources of

nutrients in coastal communities, including:

 untreated or partially treated sewage,

 effluent from sewage treatment plants,

 point sources from industrial activities,

 urban stormwater runoff, and,

 other non-point sources (e.g., agricultural runoff,

oil spills, septic tank leachate).

The addition of nutrients to the system indirectly

decreases the amount of light immediately

available for seagrasses to use for photosynthesis.

This occurs because several species of

macroalgae, phytoplankton, and epiphytic

organisms thrive in high nutrient environments,

consequently “out-competing” seagrasses for

valuable resources, especially light.

Coastal Development and

Shore Protection Structures

Rapid development of coastal communities for

residential and commercial purposes can cause

harmful habitat changes to seagrass communities.

Beyond increasing nutrient loading, increased

development is often accompanied by alteration of

coastal habitat that effectively diminishes critical

shallow-water habitat. Examples of such

alterations include the construction of seawalls,

breakwaters, revetments, groins, and jetties. Each

of these structures, aimed at protecting coastal

property, refract energy away from the shore, and

can cause erosion and increase currents that can

harm seagrasses.

Dredging Activities

Dredging can cause short and long-term impacts to

seagrass beds including physical removal or burial

of beds. Increased channelization of rivers and

streams can alter the balance between freshwater

and saltwater, resulting in unfavorable salinity

concentrations for seagrass. Indirect impacts

caused by dredging activities include increased

turbidity from suspended sediment, increased boat

traffic, and changes in hydrological conditions.

Commercial and Recreational Boating

Commercial and recreational boating can have

effects on seagrass beds. The most visible of these

impacts is propeller scarring from recreational

boaters. Scarred seagrass beds have been

observed throughout the Northern Gulf Region, and

can take as long as 10 years to return to a healthy

state. Scarring from boats can lead to the

complete degradation of a seagrass bed as erosion

impacts exposed roots and rhizomes. In addition,

sediments suspended by both recreational and

commercial vessels reduce the sunlight available to

seagrasses on a regular basis. Commercial fishing

using dragging, trawling, or digging techniques can

cause damage to the sea floor where grasses are

present. For example, shrimping, the largest

commercial fishery in the Gulf, is accomplished

with the assistance of bottom trawls that scrape

the sea floor to harvest the shrimp (Texas Parks

and Wildlife Department, 1999).

14 SEAGRASS HABITAT IN THE GULF OF MEXICO: Degradation, Conservation and Restoration of a Valuable Resource
 S E A G R A S S H A B I T AT I N T H E G U L F O F M E X I C O : Degradation, Conservation and Restoration of a Valuable Resource 15

Source: South Florida Water Management District

Source: South Florida Water Management District
Overview of Seagrass Habitat in the Gulf

Laguna Madre

SC 69,517 hectares in 1998 in the Upper & Lower Laguna Madre

HT 25 % Decline in Lower Basin,67% increase in Upper Basin since 1965

4% decrease in the area as a whole.

CD Dredging, Sediment Resuspension from Dredge Deposits, “Texas Brown

Tide”

Coastal Bend

SC 11,385 hectares in the Coastal Bend area in 1994.

HT Increase of 801 hectares since 1958 in the Redfish Bay/Harbor Island

and Mustang Island subsegment of Corpus Christi Bay.

CD Nutrient Loading, Dredging Impacts, Waterfront Construction

Galveston Bay

SC 210 hectares in 1998

HT 2,025 hectares in 1956, Trinity River Delta Not Included in Estimate

CD Shoreline Development, Habitat Alteration, Nutrient Loading

Chandeleur Islands

SC 4,511 hectares Estimated in 1995

HT 6,377 hectares in April 1969, 4,669 October 1969, 6,536 in 1992

CD Tropical Storms, Natural Loss of Island Sediment

Mississippi Sound

SC 298 hectares of seagrass in 2003

HT 600 hectares of seagrass in 1992

CD Decline in water quality, Recreational uses

Mobile Bay

SC 57 hectares of seagrass alone, 200 hectares of seagrass mixed w/

freshwater species in 2003

HT 1,105 hectares of fresh and saltwater SAVs in 1981.

CD Tropical Storms, Increased Suspended Sediments from Development

Practices

Perdido Bay

SC 120 hectares in 2003

HT 74 % Decline from 475 hectares in 1940

CD Nutrient Loading, Wastewater Effluent, Marinas, Docks, GIWW Dredging

Pensacola Bay

SC 1,814 hectares Estimated in 1992

HT Over 50 % Decline from 3,800 Hectares in 1960

CD Sewage/Industrial Waste, Dredging Activities, Beachfront Alteration

2

3

7

6

8

1

16 SEAGRASS HABITAT IN THE GULF OF MEXICO: Degradation, Conservation and Restoration of a Valuable Resource

4

5
Choctawhatchee Bay

SC 1,722 hectares Observed in 1992

HT Significant Loss between 1949 and 1985, 1,237 hectares in 1983

CD Eutrophication, Propeller Scarring from Recreational Boats

St. Andrew Bay

SC 3,979 hectares recorded in 1992

HT 4,706 hectares recorded in 1964.

CD Atmospheric Deposition of Nutrients, Stormwater Runoff, Propeller Scarring

Big Bend

SC 250,000 hectares observed in 1992

HT 520,000 hectares in 1984

CD Hydrological Alterations, Nutrient Enrichment

Tampa Bay and St. Joseph Sound

SC 10,554 hectares Observed in 2002

HT 35 % Decline from 16,000 Hectares 1950, Increase from 1982 (8,800

Hectares)

CD Rapid Population Growth, Dredging Activities, Non-Point Pollution

Sarasota Bay

SC 3715 hectares Found in 2002

HT 215 hectare Increase from Total of 3500 in 1988.

CD Rapid Urbanization, Wastewater Treatment

Greater Charlotte Harbor

SC 21,802 hectares Recorded in 1999

HT 23,127 hectares in 1982, a 6% decrease on coverage

CD Increases in turbidity & total suspended solids in the water column,

changes to freshwater flows, dredging

Florida Bay

SC 124,787 hectares Estimated in 1994

HT 142,473 hectares in 1987.

CD Increased Turbidity, Chronic Light Reduction

13

12

14

9

10

11

15

 S E A G R A S S H A B I T A T I N T H E G U L F O F M E X I C O : Degradation, Conservation and Restoration of a Valuable Resource 17

SC - Most Recent Seagrass Coverage Estimates,

HT - Historical Seagrass Coverage Trends,

CD - Most Common Causes of Seagrass Degradation.
Seagrass Habitat in My Area

This report represents an effort of several federal,

state and local agencies and organizations within

the Northern Gulf Region to estimate existing

seagrass beds and to determine losses to this

valuable habitat over the past century. The

following section represents the initial results of

this effort, exploring the historical seagrass

coverages, current trends, and significant threats

to both short- and long-term seagrass productivity.

Texas

Laguna Madre

Laguna Madre is located in southernmost coastal

Texas between Padre Island, the longest barrier

island in the world, and the mainland. This region

provides 40-50 percent of the commercial fish

catch in Texas and is also the wintering grounds of

the Redhead Duck (Aythya americana). Seagrass

meadows occur in separate Upper (Northern) and

Lower (Southern) Basins. It is estimated that 67

percent of the Lower Basin and 63 percent of the

Upper Basin are covered in seagrasses. Prevalent

species found in the system include turtle grass,

shoal grass and manatee grass. Seagrasses have

declined by 25% in the Lower Basin while

increasing by 67% in the Upper Basin since 1965.

For the lagoon as a whole, seagrasses declined by

4% over the period. The construction of the Gulf

Intracoastal Waterway and turbidity resulting from

resuspension of dredge deposits, along with the

appearance of the “Texas brown tide” in the 1990s,

have contributed to seagrass declines in Laguna

Madre.

Coastal Bend

The Coastal Bend region includes the estuarine

complexes of Corpus Christi Bay, Redfish Bay, and

the Nueces Bay system, receiving the waters of

the Nueces, Mission and Aransas Rivers to the

north and west. This environmentally sensitive

area was incorporated into the National Estuary

Program in 1988 and is home to several threatened

or endangered species, including the bald eagle,

piping plover, and Kemp’s Ridley sea turtle. Total

estimates of seagrasses in the Coastal Bend area

in 1994 are 11,385 hectares (28,120 acres), with

8,278 hectares (20,446 acres) being located in the

Nueces Bay/Redfish Bay/Corpus Christi Bay

system and the remaining 3,107 hectares (7,674

acres) being located in the Copano Bay/Aransas

Bay system. Shoal grass is the most common of

the seagrasses in the area, with turtle grass and

wigeon grass representing smaller populations.

Historical trends have shown oscillating

populations between 1958, 1975, and 1994. There

were increases between 1958 and 1994 of 330

hectares for the Redfish Bay/Harbor Island

subsegments and of 471 hectares for the Mustang

Island subsegment of Corpus Christi Bay. Although

the seagrass appears to be thriving in this area,

potential future threats to seagrass in this area

include nutrient loading, dredging impacts, and

direct physical disturbances such as waterfront

construction and propeller scarring.

Galveston Bay

Galveston Bay is the 7th largest estuary in the

United States and a major contributor to state

commercial fish landings, accounting for 35

percent of the shrimp, 30 percent of the blue crab,

and 60 percent of the oyster catch during the

1990s. The Bay is composed of the Upper

18 SEAGRASS HABITAT IN THE GULF OF MEXICO: Degradation, Conservation and Restoration of a Valuable Resource
 S E A G R A S S H A B I T A T I N T H E G U L F O F M E X I C O : Degradation, Conservation and Restoration of a Valuable Resource 19

Galveston Bay, West Galveston Bay, and the

Christmas Bay system. Over 95 percent of the

historic seagrass beds have been lost in the region.

In 1956, approximately 2,000 hectares (5,000

acres) of seagrasses were observed in this area.

However, this area did not include the Trinity River

Delta, where considerable seagrasses are known

to have existed. Primary species found in this

region include wigeon grass with some shoal grass

interspersed throughout the Bay. Major causes of

seagrass degradation in the Galveston Bay are

shoreline development, habitat alteration, nutrient

loading, and tropical storms.

Central Northern Gulf Region

Chandeleur Islands

Located 25 kilometers (km) to the north of Venice,

Louisiana, and 35 km south of Biloxi, Mississippi,

the Chandeleur Islands are remains of the

Mississippi River’s St. Bernard Delta. These remote

islands are accessible only by boat or seaplane. In

1905, the entire ecosystem was designated as a

National Wildlife Refuge. Seagrass coverage was

estimated in 1995 to be 4,511 hectares (11,148

acres), a decrease from 6,377 hectares in April

1969. However, it should be noted that total

acreage has fluctuated as evidenced by estimates

of 4,669 hectares in October 1969 and 6,536

hectares in 1992. The 1969 low is attributed to

Hurricane Camille, while long-term declines are

most likely associated with the disappearance of

the actual Chandeleur Island land masses which

have experienced a 65 percent decrease over the

past century and a half. All species of Northern Gulf

Region seagrasses have been observed in the region.

Mississippi Sound

Mississippi Sound is located to the south of

Mississippi and is home to the Grand Bay National

Estuary Research Reserve. The region is

composed of Buccaneer State Park, Cat Island,

Ship Island, Dog Keys Pass, Horn Island, Petit Bois

Island, and Point-aux-Chenes Bay. Data from 1992

indicate approximately 600 hectares (1,483 acres)

of total seagrass habitat in the Mississippi Sound,

with the majority located at Horn Island and Petit

Bois Island. A recent 2003 study by Barry Vittor &

Associates, Inc. (2003), indicated the presence of

approximately 298 hectares (746 acres), for the

Alabama portion of the Mississippi Sound. Current

populations are composed primarily of shoal grass,

although other species have been found

historically. An overall decline in water quality in

the Mississippi Sound is thought to be the major

cause of degradation, in addition to the

anthropogenic effects of recreational boat use.

Mobile Bay

Mobile Bay, designated a National Estuary by the

Environmental Protection Agency, receives the

waters of the Mobile Basin, the sixth largest

watershed in the United States. Several

endangered and threatened species reside within

the boundaries of the Bay including the American

alligator, the peregrine falcon, the bald eagle, and

the gulf sturgeon. A recent report by Barry Vittor &

Associates (2003) indicated the presence of 0.52

hectares (1.3 acres) of shoal grass, 0.016 hectares

(.04 acres) of turtle grass, 56.8 hectares (142.0

acres) of wigeon grass, and 200 hectares (500.8

acres) of wigeon grass mixed with other

freshwater species.

Changes in seagrass acreage has occurred in

coastal Alabama, but as of this date, there has

been no investigation into the specific causes of
20 SEAGRASS HABITAT IN THE GULF OF MEXICO: Degradation, Conservation and Restoration of a Valuable Resource

change.

However, the large declines in seagrass coverage

in Mobile Bay have been attributed to tropical

storms and turbidity in coastal waters caused by

land development practices that increase

suspended sediments.

Perdido Bay

Perdido Bay and River form a boundary between

the States of Alabama and Florida, and are home to

several commercial and recreationally important

species including shrimp, crabs, scallops, speckled

trout, redfish, and mullet. Most recent (2003)

estimates of seagrass habitat total 120 hectares

(300 acres) of shoal grass. Based on historic

studies in 1940, 1979, and 1987, the habitat has

experienced a decline of 355 hectares (880 acres),

or 74 percent of its seagrass coverage from a total

coverage of 475 hectares (1,187 acres). The major

seagrass species are wigeon grass, shoal grass,

and turtle grass. These species have been

degraded by nutrients from wastewater effluent

and other non-point sources of pollution. In

addition, coastal development, in the form of

marinas and docks, and dredging activites in the

Gulf Intracoastal Waterway (GIWW) have

contributed to the overall decline.

Northwestern Florida

Pensacola Bay

Pensacola Bay is located in the westernmost section

of Florida’s panhandle and supports diverse ecological

communities, productive fisheries, and various

recreational uses. The Pensacola Bay system is

composed of Escambia Bay, East Bay, Pensacola Bay,

Big Lagoon, and Santa Rosa Sound, accounting for

50,400 hectares (126,000 acres) of aquatic habitat

and 885 km (550 miles) of coastline. As of 1992,

approximately 1,800 hectares (4,500 acres) of

seagrass existed in the Pensacola Bay system. This

represents a nearly 2,000 hectare loss from 1960,

when over 3,800 hectares (9,500 acres) of seagrass

were observed in the area. Santa Rosa Sound has

experienced the greatest loss, with 2,600 hectares

(6,500 acres) of seagrass in 1960 being reduced to

1,120 hectares (2,800 acres) by 1992. Shoal grass

and turtle grass are the common species of this

region. The major causes of seagrass losses in the

Pensacola Bay system appears to be sewage and

industrial waste discharges, dredge and fill activities,

and beachfront alteration.

Choctawhatchee Bay

Choctawhatchee Bay, located along northwest

Florida’s “Emerald Coast,” is an area that has

historically supported a wealth of biological resources

and provided substantial quality of life benefits.

Divided between Okaloosa and Walton Counties, the

system is separated into three segments: Western

Choctawhatchee Bay, Middle Choctawhatchee Bay,

and Eastern Choctawhatchee Bay. The most recent

study, in 1992, reported a total of 1,722 hectares

(4,261 acres) of seagrasses in the Choctawhatchee

Bay. Of this total, it was determined that 1,408

hectares (3,477 acres) were deemed “patchy”

seagrass beds and 314 hectares “continuous”

habitats. The majority of the seagrass occurs in the

western segment of the Bay, which is comprised of

shoal grass and wigeon grass. This total represents a

significant increase from studies performed in 1983,

which reported 1,237 hectares of seagrass in the

area. However, comparisons of aerial photographs

from 1949 and 1985 indicated “significant loss” for

most areas. Major causes of seagrass degradation in

the region include eutrophication and propeller

scarring from boats.
 S E A G R A S S H A B I T AT I N T H E G U L F O F M E X I C O : Degradation, Conservation and Restoration of a Valuable Resource 20

St. Andrew Bay

Located in Bay County, Florida, St. Andrew Bay

exhibits a wealth of biological diversity, providing

habitat for over 2,900 species of plants and

animals. Several of these species are commercially

and recreationally important to the socio-economic

well-being of the region. The Bay covers an area of

about 27,392 hectares and is composed of St.

Andrew Bay, West Bay, North Bay, East Bay and

St. Andrew Sound. A survey of seagrass habitat in

1992 found a total of 3,979 hectares (9,832 acres)

in this area. This represents a loss of

approximately 800 hectares since 1953. Of the

subunits, West Bay has suffered the greatest

losses, with the seagrass habitat diminishing 50

percent (to 800 hectares) by 1992. Turtle grass

and shoal grass are the major species in the region

with smaller amounts of manatee grass and

wigeon grass present. Potential causes of loss in

St. Andrew Bay include atmospheric deposition of

nutrients, stormwater runoff, and propeller scarring

from recreational boats.

Big Bend

Florida’s Big Bend is an area that has been described

as one of the least polluted coastal regions in the

United States. The region can be divided into two

subsections; the northern half, “Big Bend Proper,” and

the southern half, “Springs Coast.” Within the Big

Bend region are the Big Bend Seagrasses Aquatic

Preserve, managed by the Florida Department of

Environmental Protection, and five National Wildlife

Refuges (St. Marks, Lower Suwannee, Cedar Keys,

Crystal River, and Chassahowitzka). It is estimated

that between 25 and 33 percent of the total blue crab

landings in Florida are from Big Bend. A variety of

studies have been performed on the Big Bend area,

however due to study methods and boundary

definitions they are not comparable. In 1984, 520,000

hectares of seagrass were mapped in the area. In

1992, 250,000 hectares (619,000 acres) of seagrass

were reported. Turtle grass, manatee grass, and shoal

grass are the major species present. Threats to

seagrass in the Big Bend region include hydrologic

alterations to watersheds and nutrient enrichment of

estuaries and coastal waters.

Southwestern Florida

Tampa Bay

Tampa Bay, the largest estuary in Florida, is home to

40,000 breeding pairs of shorebirds and over 100

bottlenose dolphins. In 1990, Tampa Bay was

accepted into the U.S. EPA’s National Estuary

Program. The system is divided into seven bay

segments: Hillsborough Bay, Old Tampa Bay, Middle

Tampa Bay, Lower Tampa Bay, Boca Ciega Bay, Terra

Ceia Bay, and the Manatee River. In 1999, 10,053

hectares (24,830 acres) of habitat were reported in

Tampa Bay with 10,554 hectares (26,068 acres)

reported in 2002. This figure represents a 35 percent

decrease from historical studies that recorded over

16,000 hectares (40,000 acres) of seagrasses. It

should be noted that the 1999 total is an increase

from 1982 when total acreage was estimated at

8,800 hectares (22,000 acres). Middle Bay, Old

Tampa Bay and Boca Ciega Bay have all suffered

losses. Shoal grass and turtle grass are the most

abundant in the Bay, and consequently have most

likely suffered the largest losses over time. Likely

causes of degradation include rapid population

growth, dredge and fill activities, and non-point

source nutrient loading.

Sarasota Bay

Sarasota Bay, part of the National Estuary Program,

is divided into five bay segments that include
22 SEAGRASS HABITAT IN THE GULF OF MEXICO: Degradation, Conservation and Restoration of a Valuable Resource

Upper Sarasota Bay – Sarasota County, Upper

Sarasota Bay – Manatee County, Roberts Bay,

Little Sarasota Bay, and Blackburn Bay.

Commercial fishing has been a popular activity in

the region dating back as far as the late 18th

century. In 2002, 3,715 hectares (9,181 acres) of

seagrass were identified in Sarasota Bay. This

total represents an increase from studies

performed in 1988 that indicated more than 3,500

hectares (8651 acres) of seagrass present.

However, it should be noted that historical

observations noted declines in acreage between

1880, 1950, and 1988. Shoal grass is distributed

throughout the bay, while turtle grass, manatee

grass and wigeon grass are found with less

regularity. Changes in seagrass habitat are most

likely due to the rapid urbanization of the

watershed (causing seagrass loss), and

improvements in wastewater treatment practices

(leading to increases).

Greater Charlotte Harbor

Charlotte Harbor, located on the west coast of

Florida south of Tampa Bay, is one of the State’s

most pristine and productive estuaries. The harbor

is surrounded by an extensive conservation buffer

system of well over 21,610 hectares (53,400

acres) managed by agencies of the State of Florida.

A series of National Wildlife Refuges exist along

Sanibel and Pine Islands. One of these refuges, J.N.

“Ding” Darling, attracts over 900,000 visitors per

year. In addition, the region is home to the

federally endangered American crocodile, and

many recreationally important fish species such as

the tarpon, snook, and redfish. Charlotte Harbor’s

most recent seagrass studies estimate that 21,802

hectares (53,850 acres) were present in 1999.

This total is about 1325 hectares (3,272 acres) less

than historical seagrass estimates recorded in

1982 of 23,127 hectares (57,123 acres). Shoal and

turtle grass compose the majority of the present

and historic grasses in Charlotte Harbor. Major

threats to seagrass habitat in the region include

increases in turbidity, total suspended sediment in

the water column, changes to freshwater flows,

dredging, and propeller scarring from boats.

Florida Bay

Located in the southernmost portion of Florida’s

west coast, Florida Bay is home to nearly 259,000

hectares (1,000 square miles) of interconnected

basins and mangrove islands. The region acts as

nesting, nursery, and feeding grounds for a variety

of species including manatees, bottlenose dolphins,

and loggerhead sea turtles. In addition, parts of the

Bay are fished commercially for pink shrimp.

Seagrass estimates in 1994 found 124,787

hectares (308,223 acres) of habitat in the region. In

1987, 142,473 hectares (351,908 acres) of

seagrass habitat were reported. Species found

within Florida Bay include turtle grass, followed by

smaller populations of shoal grass and manatee

grass. Current threats to habitat are increased

turbidity and associated chronic light reduction.
Seagrass degradation and loss of habitat in the Northern Gulf Region have had

significant impacts on natural resources and socio-economic vitality. However,

with the right approach, it is possible to reverse the current trends of seagrass

loss. The most important aspect of enhancing seagrasses is having a

comprehensive planning strategy that includes management practices,

conservation, educational efforts, monitoring, and restoration to enhance the

likelihood of success.

Management Practices

A variety of regulations and management policies can improve the protection and

restoration of seagrass habitats in the Northern Gulf Region. The most significant

of these are comprehensive management plans developed by state and Federal

environmental organizations. These policies create a planning framework that

allows stakeholders to engage in the decision making process.

Most comprehensive management plans include committees focusing on topics

such as research, monitoring, conservation, restoration, protection, and education,

facilitating discussion and the prioritization of major issues. While comprehensive

management plans are ordinarily directed at the state and Federal level, they are

most often implemented at the local level, allowing scientists and managers to

apply general mandates for seagrass enhancement to a specific region.

Some regulations, such as boating restrictions focused on reducing propeller

scarring, create enforceable guidelines that directly enhance the quality of

seagrass habitats. With proper enforcement these regulations prevent

unnecessary degradation throughout critical areas. Other examples of regulations,

such as those aimed at point and non-point pollution or coastal development

practices (e.g., zoning, coastal structure permits) act indirectly to reduce

anthropogenic impacts the Northern Gulf Region.

How are We Improving Damaged

Seagrass Habitat?

 S E A G R A S S H A B I T A T I N T H E G U L F O F M E X I C O : Degradation, Conservation and Restoration of a Valuable Resource 23
Educational Programs

Promotional literature and informational websites are excellent tools for

communicating with the general public. Federal and state authorities also

can coordinate with local government and non-profit organizations to

engage local citizens in restoration efforts and educational workshops.

Mechanisms for financing (e.g., grants) for public participation are important to assure regional policies are implemented at the local level.

Monitoring

Monitoring is the cornerstone of any comprehensive program to protect or

restore seagrass species in the Northern Gulf of Mexico. This Status and

Trends Report represents an initial effort to create a baseline of information

and increase stakeholder awareness. While historic seagrass monitoring

in the Gulf has been sporadic, recent efforts (United States Geological

Survey, 1992) have established large-scale consistent data sets for the

Northern Gulf Region.

Keys to successful monitoring efforts include establishing geographic

parameters, creating consistent data sets and interpretation techniques,

investing in field verification of aerial photos, identifying seagrass species,

and measuring water and sediment quality. Monitoring efforts are best

implemented by local entities that have an understanding of their dynamic

ecosystem, and coordinated by larger organizations (e.g., GMP, USGS) that

can guarantee consistent methodologies.

Restoration

Restoration of seagrasses is an important part of any comprehensive plan

to manage seagrass loss in the Northern Gulf Region. Seagrass programs

often attempt to achieve “no net loss” of habitat through compensatory

mitigation practices. Compensatory mitigation depends on the success of

efforts by state and local agencies to increase the quality and quantity of

degraded seagrass beds. Critical to these programs is the planning process, which identifies priority sites for restoration based on a comparison

of regional seagrass habitats (Texas Parks and Wildlife Department, 1999;

Beck et al., 2000).

Seagrass planting efforts to reestablish beds requires a detailed effort and

although these efforts may further research and educate on the importance

of seagrasses, they do not necessarily result in large areas of seagrass

restoration. Seagrass coverage has increased in some areas of the Gulf

primarily as a function of improvements in water quality, and water quality

has improved as anthropogenic influences, both point and non-point

sources have been reduced.

24 SEAGRASS HABITAT IN THE GULF OF MEXICO: Degradation, Conservation and Restoration of a Valuable Resource
This document presents a brief overview of the status and trends of seagrasses in

the Northern Gulf Region. Historic trends in several areas show that within the

past decade seagrasses are increasing, mostly as a function of improvements in

water quality. Water quality improves in an area when point and non-point source

pollution are reduced.

With the establishment of baseline seagrass coverage estimates the Gulf States

now have a tool to monitor the seagrass beds and to detect which areas are

improving and which areas are being damaged or compromised in some way.

Going forward, the Gulf of Mexico Program hopes to reverse the current trend of

seagrass habitat degradation by implementing a comprehensive research,

conservation, and restoration program. This program, created by the habitat focus

team and its expert panel members, intends to:

 Assess the areal and temporal extent and quality of seagrasses,

 Analyze trends in the extent and quality of seagrass habitats,

 Identify factors that determining the establishment and persistence of

 seagrasses, and,

 Ascertain the critical factors determining natural structural and functional

 characteristics of seagrass habitats.

 S E A G R A S S H A B I T AT I N T H E G U L F O F M E X I C O : Degradation, Conservation and Restoration of a Valuable Resource 25

Seagrass ready for planting in the northern Gulf of Mexico. Source: Ron Phillips.

What Does the Future Hold

for Seagrasses?
Literature Cited

Beck, M.W., M. Odaya, J.J. Bachant, J. Bergan, B. Keller, R.

Martin, R. Mathews, C. Porter, G. Ramseur. 2000. Identification of Priority Sites for Conservation on the Northern Gulf of

Mexico: An Ecoregional Plan. The Nature Conservancy,

Arlington, VA. http://www.conserveonline.org/2001/02/b/en/

gulf.pdf

Britton, J. C. and Martin, B., 1989. Shore Ecology of the Gulf

of Mexico. University of Texas Press. 329 pp.

FDEP. 2001. Florida Department of Environmental Protection.

Seagrass and the Economy. http://www.dep.state.fl.us/

coastal/seagrass/facts/economy.htm Site Visited June 20,

2003.

Fonseca, M. S. 1994. A Guide to Planting Seagrasses in the

Gulf of Mexico. Texas A&M University Sea Grant College

Program. TAMU SG-94-601. 27 pp

Dawes, C., R. Phillips and G. Morrison. In press. Seagrass

Communities of Florida’s Gulf Coast: Status and Trends.

Edited by H. Greening. Tampa Bay Estuary Program, FWC,

Florida Marine Research Institute, and U.S. Geological

Survey.

Jaap, W. C. and P. Hallock. 1990. Chapter 17 - Coral Reefs. In

Ecosystems of Florida. Edited by Ronald L. Myers and John

J. Ewel. 765 pp.

Kuo, J. and A.J. McComb, 1989. Chapter 2 - Seagrass

Taxonomy, Structure and Development. In Biology of

Seagrasses. Edited by A.W.D. Larkum, A.J. McComb and

S.A. Shepherd. 842 pp.

Phillips, R.C. and E. G. Meñez,. 1988. Seagrasses.

Smithsonian Contributions to the Marine Sciences. Number

34, 104 pp.

NOAA, 1997. The 1995 national shellfish register of classified

growing waters. Office of Ocean Resources, Conservation

and Assessment, Strategic Environmental Assessments

Division. Silver Spring, MD, 398pp.

NOAA, 2003. National Oceanic and Atmospheric Administration Data from Commercial Fisheries Website. http://

www.st.nmfs.gov/st1/commercial/ Site visited June 20,

2003.

Texas Parks and Wildlife Department. 1999. Seagrass

Conservation Plan for Texas. Texas Parks and Wildlife, Texas

General Land Office, Texas Natural Resources Conservation

Commission, Galveston Bay Estuary Program, Coastal Bend

Bays and Estuaries Program. 79 pp.

Short, F.T. and R.G. Coles (eds.). 2001. Global Seagrass

Research Methods. Elsevier Science B.V., Amsterdam, 482

pp.

Mobile Bay National Estuary Program, Benthic Mapping of

Submerged Aquatic Vegetation in Mobile Bay and Adjacent

Water of Coastal Alabama, prepared by Barry A Vittor &

Associates, Inc., Mobile, Alabama, July, 2003, pp. 27,

appendices.

In order to reach these objectives it will be

necessary to take several steps to better

understand the quality and extent of seagrass

habitat in the Northern Gulf. These will include:

quantifying and mapping current seagrass acreage;

identifying indicators that best describe the health

or quality of seagrass beds; identifying water

quality, water column, and sediment

characteristics and their impacts on seagrasses;

determining the relationships between primary and

secondary productivity and landscape features;

and exploring how habitat functions differ among

different seagrass species.

The next decade will be crucial for seagrass in the

region due to the expectation that coastal

populations will continue to rapidly increase.

Without comprehensive planning, education, and

enforcement, it is very possible that seagrasses

will continue to disappear from the estuaries and

coastal waters of the Northern Gulf Region.

However, with the assistance of Federal, state and

local agencies, as well as a coordinated effort of

citizens at the local level, the chances of increasing

seagrass habitat are very real.

26 SEAGRASS HABITAT IN THE GULF OF MEXICO: Degradation, Conservation and Restoration of a Valuable Resource
Seagrass Status and

Trends Steering Committee:

 Diane Altsman, EPA/Gulf of Mexico Program

 Richard DeMay, Barataria Terrebonne National Estuary Program

 Larry Handley, USGS, National Wetlands Research Center

 Jimmy Johnston, USGS, National Wetlands Research Center

Seagrass Status and

Trends Committee Members:

 Chris Onuf, Laguna Madre

 Beau Hardegree and Teri Nicolau, Texas Coastal Bend

 Warren Pulich, Texas Coastal Bend, Galveston Bay, Texas -

State

 Mike Poirrier and Larry Handley, Chandeleur Islands

 Cynthia Moncreiff, Mississippi Sound and Gulf Islands

 Judy Stout, Diana Sturm and Carl Ferraro, Mobile Bay

 Paul Carlson and Kevin Madley, Florida - State

 Taylor Kirschenfeld and Robert Turpin, Perdido Bay

 Lisa Schwenning and Traci Bruce, Pensacola Bay

 Barbara Ruth, Choctawhatchee Bay

 Mike Brim and Larry Handley, St. Andrew Bay

 Rob Mattson, Thomas Frazer, Jason Hale, Seth Blitch, and

Lisa Ahijevych, Florida Big Bend

 Dave Tomasko and Holly Greening, Tampa Bay and

St. Joseph Sound

 Gary Raulerson and Dave Tomasko, Sarasota Bay

 Catherine Corbett and Kevin Madley, Charlotte Harbor

 Margaret Hall, Michael Durako, James Fourqurean,

Kevin Madley, Joseph Zieman, Michael Robblee, Florida Bay

 Mike Beck, General Seagrass Information

 Bill Kruczynski, General Seagrass Information

 Pete Sheridan, Seagrass Species Information

 Pete Bourgeois and Blaire Hutchison, Mapping
Gulf of Mexico Program Office

Mail Code: EPA/GMPO

Stennis Space Center, MS 39529-6000

http://www.epa.gov/gmpo/

855-R-04-001