Florida Seagrasses: Key Takeaways from the TCC FAEP Workshop

Discover valuable insights from the TCC FAEP Seagrass Workshop, focusing on Florida seagrass restoration techniques, survey methods, and examples of key seagrass species. Learn how these practices contribute to protecting Florida’s marine ecosystems and ensuring the success of your environmental projects.

1. www.CumminsCederberg.com
Part I: Seagrass Identification
TCC Seagrass Identification & In-Water Survey Workshop
Michael, Yustin, Senior Project Manager, Martin County
August 2024

2. Seagrasses
•Belong to the angiosperm (flowering
plants) group
•Similar to terrestrial plants, seagrasses
can be divided into:
•Leaves (contain veins)
•Stems
•Roots (buried in the substrate)
•Reproductive parts (flowers and
fruits)
•Differences between seagrasses and algae
•Algae does not have veins in leaves
•Algae uses holdfast to anchor to
surface (no roots)
•Algae does not produce flowers
•Seven species found in South Florida

3. Seagrasses
•Leaf Shapes
•Oval (paddle or clover) -Halophila
•Long spaghetti like leaf -Syringodium
•Ribbon shaped leaf –Thalassia•Identification Features
•Sheath –base of a leaf (protects new
leaves)
•Leaf
•Vertical steam (found in some species) –
upright axis of the plant form which leaves
attach.
•Scars –remnants of leaf attachments
•Roots and rhizomes (horizontal stems)
•Nodes and internodes
•Petiole (found in some species)

4. Turtle Grass (Thalassia
testudinum)
•Largest Florida seagrass
•Base sheathing –2 to 5 in a group
•Large ribbon-like leaves (o.5 to 1 cm
wide and up to 30 cm long)
•Rounded leaf tip
•Long jointed rhizomes –buried in the
substrate 2 to 4 inches.
•0.5 –1 cm diameter
•Divided into nodes
•Internodes about 1 cm long
•Covered by scale leaves
•Flowers grow on short stalks in the axils
of the leaves
•Greenish-white

5. Shoal Grass (Halodule
wrightii)
•Early colonizer
•Usually grows in water too
shallow for other species
•Flat bladed, narrow leaves,
resemble terrestrial grass
•0.5 to 3 mm wide
•Rounded tip
•Reaches heights up to 12”
•Internodes 2 to 3 cm long,
bearing a short shoot and root
group at each node.

6. Manatee Grass
(Syringodium
filiforme)
•Cylindrical thin leaves, 2 to 4
mm diameter, rounded tips
•Up to 35 cm long
•Groups of 2 from short shoots
•Bearing erect short shoots
at each node
•Internodes 2-3 cm long
•Blades round or oval in cross-
section

7. Paddle-grass
(Halophila decipiens)
•Small, oval shaped leaves –grow
1 –2.5cm long (longer than
wider)
•White vein down the middle,
with 6-8 cross veins per blade
•Grow 1” wide by about 3” tall
•Leaf hairs on both sides
•Margin of blade serrulate
•Leaves in pairs

8. Johnson’s seagrass
(Halophila johnsonii)
•Pairs of linearly shaped leaves
•Leaves 0.2 to 1 inches
•Margin of blade smooth
•Leaves in pairs

9. Widgeon grass
(Ruppia maritima)
•Short, linear, thread-like leaves,
3 to 10 cm long and 0.5 to 1mm
wide
•In clusters of 2 to 4.
•Leaves arranged alternately
along slender, branching stems
•Blades flat -usually of uniform
width or tapering to the tip,
blades 1mm wide, tapering, tip
pointed.
•Stem a horizontal underground
rhizome

10. Stargrass(Halophila
engelmanii)
•Elongated leaves, oval, serrated
margin
•Petioles 4mm long or less
•Cluster of 2 to 4 pairs at the
erect shoot
•Slender horizontal rhizome –1-
2mm diameter, growing along
the surface of the sediment or
just beneath
•Erect shoots at the nodes –4 to
10 cm tall
•One pair of scale leaves on the
rhizome at the base of the erect
shoots
•Second pair about halfway
up the erect shoot

11. www.CumminsCederberg.com
Part II: Seagrass Survey Methods
TCC Seagrass Identification & In-Water Survey Workshop
Gina Chiello, Senior Director, Cummins Cederberg
August 2024

12. www.CumminsCederberg.com
Overview
Overview
Seagrass Growing Seasons
Field Mobilization
Field Work and Data Collection
Overview
•Seagrass Growing Season
•Field Mobilization & Equipment
•Field Notes/ Data Recording
•Seagrass Survey Methods
•In-Water Survey Prep

13. Overview
Overview
Seagrass Growing Seasons
Field Mobilization
Field Work and Data Collection
Seagrass Growing Season
•Refer to the “TCC Seagrass Identification and In-Water Survey Workshop”handout
•Miami-Dade County DERM –Year-round
•State –April 1st –October 31st , except for south of Rickenbacker Causeway through the
Florida Keys –Year-round
•Federal –June 1st –September 30th
•Federal Exceptions in Miami-Dade and Monroe Counties on a case-by-case basis

14. Kick Off Meetings
Field Mobilization & Equipment
•AirTanks(80CYor60CY)
•Scubagear
•Diveweights
•Snorkelgear
•Gloves,wetsuitorrashguardandleggings
•Closetoedshoes
•Toweddiveflag
•Trimble
•Trimbledrybag&float
•Transecttapes
•Cameras&Housing
•Extrabatteries
•Firstaidkit
•DANO2kit
•Whistle/horn
•Datasheetsonunderwaterpaper
•Copyofdiveorsnorkelplan
•Fieldbook
•Clipboards
•Pencils,rubberbands,clips
•Zipties
•Weightedbuoys
•Surveyrod
•Ladder
•Sunscreen/hat/SPFprotectiveclothing
•Water,Food

15. Kick Off Meetings
Field Notes
•Date
•Job No.
•Staff on site
•Time of day –departure
•Important information –weather, field concerns (e.g., boat traffic), notifications to DSO/client
•Work sequencing, times, etc.
•Example: 0900 –Laid buoys for Transects 1 –4
0910 –Divers RD, GC in at transect 2
0945 –Divers complete transect 2, move to transect 3
1000 -Transect 3 aborted –did not complete due to sunken boat
•Set up diver in/out table with max depth
•Make any notes that are helpful –visibility, currents, MA blooms, jellyfish.

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Kick Off Meetings
Data Recording
•Datasheets printed on underwater paper (e.g., Duracopy)
•Prompt you to collect data in a consistent manner
•Edit the datasheets depending on what the survey is for.
•Date, data collector, visibility, max depth, seagrass
species, total BB score, macroalgae BB score, notes
•Be efficient and consistent in your data collection. Use
shorthand.
•Hd, Hw, Tt, Sf, He, Hj(seagrass species)
•Cyano(cyanobacteria)
•Hali, Acet, Caul, Sarg, Turg, Dict, Drift, Pen
(macroalgae species)
•Epi (epiphytes)
•SS, CS, FS, Muck, Clay, Silt, Shell, RR (substrate
types)

17. Kick Off Meetings
Seagrass Survey Methods and Data Collection
•Mapping/ Survey Methods
•Direct Edge (Trimble and Hypack)
•Line Intercept and Belt Transect
•Reconnaissance Surveys (S swims, concentric circles)
•Systematic Grid Sampling
•Cover Abundance
•Braun Blanquet
•Frequency of Occurrence/ Cell Counts
•Density
•Percent Cover
•Short Shoot
Counts
•Other Parameters
•Epiphytic Cover
•Blade Height
•Sedimentation
•Substrate type
•Sediment depth
•Drift algae

18. www.CumminsCederberg.com
Seagrass Survey Methods
Direct Edge Mapping
•Direct edge mapping using Trimble
•2 Divers, one on bottom, one on surface manning
float w/ unit
•High-viz following from surface
•Low-viz –tethered, signals (pull system)
•Sink dive watch with Trimble and take notes
•Direct edge mapping using Hypack
•Diver recon, leave “Cookie crumbs” of buoys
•Collect series of points that will be linked in GIS

19. Seagrass Survey Methods
Line Intercept/ Belt Transects
•Distances across linear and/or perpendicular transects –habitats mapped
via distance along lines. Allows for coverage estimates.
•Line Intercept
•What habitat the transect tape touches.
•Biological monitoring coupled with additional methods.
•Belt Transects
•Within visible range of the transect tape.
•Mapping
•Density of specific flora/fauna

20. www.CumminsCederberg.com
Seagrass Survey Methods
Reconnaissance Survey
•S swims, meandering patterns
•Can be used to plan methods for survey events
•Can take GPS fix if important resources observed
•Concentric circles
•Good for low visibility when looking for resources
around a structure such as buoys, navigation markers,
pilings etc.
•Can take GPS fix if important resources observed
Systematic Grid Sampling
•Can be done across large areas; set up different sized
cells to collect quads on and characterize habitat; not
highly detailed but can assist for planning and design in
big project areas

21. Cover Abundance–Braun Blanquet
•Used to assess abundance
•Quadrat sizes can vary
•1.0 x 1.0 m =1 m
2
•0.7 x 0.7 m = 0.5 m
2
•Clean off blades, bring upright, clear out drift algae
•Seagrass canopy does not equal seagrass cover
•Place a quadrat (typically 1m
2
) at points along a transect
•Record all species of seagrass occurring in the quadrat
•Assess the coverage of each species of seagrass
individually, total seagrass and if warranted the total
macroalgae using the BB scoring index
•Record BB score by species and by Total SG –These are
NOT Additive
•Example: 0.1 HW, 1.0 SF do not equal 1.1 TSG
•Frequency of Occurrence/ Cell Counts

22. Percent
Cover
Presence/Absence –Percent Cover
•Estimate the total %
seagrass within the quadrat
•Determine the percent
contribution of each species
to the total percent cover

23. Density –Short Shoot Counts
•Akeycomponenttoassessseagrassbed
health
•Mostseagrassesgrowasshoots(i.e.,bundles
ofleaveswithinasheath)thatemergefroman
undergroundrhizome
•Shootcountsareconductedwithinaportionof
aquadrat(tobedefinedintheproject
methodology)
•Useyourhandtopushbackallshootstoone
side,gentlyteasesshootbyshootoutfrom
theirhandusingapencilorfinger,while
countingeachshortshoot
•Totalofshootcountperspeciesisrecorded

24. Blade Height (Canopy Height)
•Canopy height is an indicator of the structural role that seagrass plays in providing
habitat and refuge to marine animals that live amongst the plants
•In the quad, the biologist grabs a handful of rooted plants with leaves without
uprooting them.
•Extend the leaves to their maximum height and measure with a ruler (nearest mm
usually)
•Depending on the methodology, you might record max, min or several measurements
to find the average

25. Data Collection Parameters –Other
•Epiphytic Cover (Typically, Low, Mod., High)
•Prominent component of seagrass communities
(important food source)
•Algae, crustaceans, mollusks, tunicates,
fungi/bacteria, sponges, hydroids and bryozoans
•Reduce light availability
•Sedimentation (on blades and covering epiphytes)
•Substrate type (touch it!)
•Sediment depth (up to 30 cm)
•Drift Algae –note species and percent cover and
remove after evaluating

26. Other Considerations
•FKNMS requires a permit to conduct benthic surveys within the sanctuary & they
have their own protocols
•Take photos of your data sheet
oIn case it gets blown off a boat or floats away
oTo identify photos
•Photography -make your photos useful for reports & marketing
•Photo with a ruler for size comparison (or marked pvc)
•Quadrats
oPhoto of quadrat from bird's eye view
oPhoto or two of important resources within the quadrat

30. TCC FAEP Seagrass Identification and In-Water Survey Workshop August 2024

Useful Resources:
Caribbean Reef Plants by Littler and Littler
The Reef Set – Reef Creature, Fish, and Coral Identification by Paul Humann and Ned Leloach
Peterson’s Field Guide to Coral Reefs: Caribbean and Florida by Eugene H. Kaplan
Recommendations for Sampling Halophila johnsonii at a Project Site as referenced in the Johnson’s Seagrass
Recovery Plan (National Marine Fisheries Service, 2002). https://repository.library.noaa.gov/view/noaa/15973

Florida Department of Environmental Protection. Dec 8, 2020. Guidance on Surveys for Submerged Aquatic
Vegetation Compensatory Mitigation Projects.
Florida Fish and Wildlife Conservation Commission. 2011. Recommended Survey Protocols for Estuarine and
Marine Submerged Aquatic Vegetation related to Permitting Applications (Draft).
Karazsia, J. NOAA NMFS Southeast Region, Habitat Conservation Division. 2010. A Science-based Seagrass
Survey Window for Coastal Construction Project Planning in Florida.
National Marine Fisheries Service, Southeast Region Habitat Conservation Division. 2010. Best Management
Practices for Surveying Seagrass for Coastal Construction Planning in Florida.
National Oceanic and Atmospheric Administration National Marine Fisheries Service. 2007. Endangered
Species Act 5-Year Review Johnson’s Seagrass (Halophila johnsonii Eiseman).
U.S. Army Corps of Engineers. 2018. Submerged Aquatic Vegetation Survey Guidelines.
Seagrass Survey Windows for South Florida:

AGENCY SPECIES GROWING SEASON EXCEPTIONS/ NOTES REFERENCES

Miami-Dade
County DERM

All species

Year-round

None

DERM Procedures
FDEP/SFMWD
All species June 1 – September 30
FDEP requires a June 1 –
September 30 survey to
grant SPGP; May accept
year-round for smaller
projects in Monroe
County and southern
Dade County.


(FDEP, 2020)

USACE All species

June 1 – September 30
Lenient with smaller
projects in Miami-Dade
and Monroe Counties

(Karazsia, 2010)
(NMFS, 2010)

NMFS All species

June 1 – September 30
May accept year-round
for smaller projects in
Monroe County

(Karazsia, 2010)
(NMFS, 2010)

FKNMS
All species


June 1 – September 30
May accept year-round
for smaller projects in
Monroe County

(Karazsia, 2010)
(NMFS, 2010)

31. TCC FAEP Seagrass Identification and In-Water Survey Workshop August 2024

Braun-Blanquet Cover-Abundance Scores

Score Description of Cover
0 Taxa absent from quadrat
0.1 Taxa represented by a solitary shoot, <5% cover
0.5 Taxa represented by a few (<5) shoots, <5% cover
1 Taxa represented by many (>5) shoots, <5% cover
2 Taxa represented by many (>5) shoots, 5 - 25% cover
3 Taxa represented by many (>5) shoots, 25 - 50% cover
4 Taxa represented by many (>5) shoots, 50 - 75% cover
5 Taxa represented by many (>5) shoots, 75 - 100% cover

Conversions for Braun-Blanquet Cover-Abundance Scores to Percent Cover

Score Median Percent Cover (%)
0 0
0.1 0.02
0.5 0.1
1 2.5
2 15
3 37.5
4 62.5
5 87.5










Miami-Dade County Division of Environmental Resources Management (DERM), Florida Department of Environmental
Protection (FDEP), South Florida Water Management District (SFWMD), U.S. Army Corps of Engineers (USACE), National
Marine Fisheries Service (NMFS), Florida Keys National Marine Sanctuary (FKNMS)

32. 0.5

BBCA 0.5; <5% for seagrass few shoots BBCA 1; <5% numerous shoots BBCA 2; 10-15%


BBCA 3; 40% BBCA 4; 75% BBCA 5; 100%