1. Seagrass San Carlos Bay 11/19/13 Florida Coastal Office
Melynda Brown- Charlotte Harbor Aquatic Preserves

2. What is Seagrass Vascular Photosynthetic
Occurs in tropical and temperate waters
Species adapted to variety of environmental conditions
Indicator Species
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3. Benefits of Seagrass Improves water quality and stabilizes sediment
Nutrient and carbon cycling- higher than rainforests
Provides shelter, nursery and food source for 90% of commercial and recreational important fisheries
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4. Value of Seagrass ~2.2 million acres of seagrass in Florida waters,
Provide ecological services worth over 40 billion
each year (Carlson and Yarbro, 2009).
= $20,000 per acre of seagrass
A recent study for Pine Island Sound/SWFL
(Beever 2012) found that continuous seagrass
Total Economic Value was $93,829/ acre.
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5. Syringodium filiforme
Common SWFL Species
Halodule wrightii
(Shoal grass)
Thalassia testudinum
(Turtle grass)
Syringodium filiforme
(Manatee grass)
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6. Seagrass Monitoring Charlotte Harbor AP: -Began in 1999 -50 transects
-Annually; Aug-Oct.
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7. Seagrass Monitoring DEP South District EAR:
-3 River transects began in 2001
-3 CHAP transects since 2008
-Quarterly: Feb, May,
August and November
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8. Stressors to Seagrass Boat traffic- waves and propscars
High flow- erosion/sedimentation
Tidal exposure
Temperature
optimal 20-30oC (68-86oF) Zieman 1982
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9. Light availability: depends on color, turbidity, chlorophyll levels
Stressors to Seagrass
Light availability: depends on color, turbidity, chlorophyll levels
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10. Effects of stressors
High Nutrient Loading: increase in algae blooms decrease in seagrass abundance
SCCF
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11. Nutrient Loading and Seagrass Production
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12. Stressors to Seagrass Salinity Levels- varies by species Dense
Decreased light
High salinity
Decreased salinity
Sparse
T. testudinum
S. fliforme
H. wrightii
Dense
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From Greenawalt et. al. 2004

13. Seagrass Abundance by Region
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14. Mean Abundance in San Carlos Bay vs. Annual S-79 Flow
NEW GRAPH!!
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15. Site Specific Data
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16. Low salinities: decreased seagrass abundances and species shifts
Hurricane Wilma/
highest flows
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17. SC03 Density
3,600
Hurricane Wilma/
highest flows
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18. Conclusions & Next Steps
Goal: abundant and diverse seagrass beds
High flow can cause variable salinities in estuaries, leads to decrease in abundance or species shifts and loss
Salinity driven or other contributing factors?
Combine all water quality and seagrass data for bigger picture view of affects
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19. Thank You
Charlotte Harbor Aquatic Preserves Burnt Store Rd Punta Gorda, FL 33955
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