2010: Project #9007 Restore-A-Scar Seagrass Restoration of Propeller Scars Tampa, Florida

Project name: Restore-A-Scar Seagrass Restoration of Propeller Scars

Project number: 9007

Project status: In Progress

Grant Administrator: Gulf of Mexico Foundation (for NOAA)

Grantee: The Ocean Foundation

Project location: Tampa Bay, Florida

Grant period: Jan 1 - Dec 31, 2020

Grant amount: $25,000

Land Ownership: Public

Lat/Long: Multiple Locations

Types of Habitat: Seagrass Bed

Project leader: Jeremy Linneman, Special Projects Director

The Ocean Foundation

1990 M Street NW, Suite 250

Washington, DC 20036



Species Benefiting From Restoration:

• Halodule wrightii (Shoal grass)

• Thalassia testudinum (Turtle grass)

• Syringodium filiforme (Manatee grass)


Acres of Habitat To be Restored:

7,000 linear feet of scars, spread out over at least 50 acres of seagrass meadow will be restored.


Project Summary:

Seagrass meadows are disappearing, and so too are the services they provide to other animals in the sea. The best estimate is that we have lost over 25 percent of seagrass meadow coverage in the world’s ocean in the last four decades. The losses continue on a daily basis due to the many threats faced by seagrass, such as scars and blowouts created by boat propellers, anchors, and vessel groundings. Propeller scars are areas that have been stripped of aquatic plant life as a result of the propeller of a moving boat inadvertently being allowed to come into contact with the estuary bottom, thereby cutting not only the seagrass blades, but more catastrophically, slashing underground rhizomes and roots as well. A blowout typically results when the hydraulic action of a propeller wash forms a hole in the estuary bottom. Left unchecked, these types of damages leave the seagrass meadow vulnerable to further erosion, and can eventually destroy the whole seagrass bed. For this proposal, all restoration activities will take place in Cockroach Bay Aquatic Preserve in Tampa Bay, Florida.


On-the-Ground Activities:

To restore areas of seagrass that have been damaged by propeller scars and blowouts, the restoration contractor employs its Sediment Tube technology to replace sediment into damaged areas while minimizing the turbidity of the water. The Sediment Tube is made of specialized cotton that biodegrades fully over a period of 3 – 5 months and is filled with native sediment to provide a viable growing medium. After approximately three to five months, seagrass planting units are inserted into the partially degraded Sediment Tubes. Based upon our experience, complete seagrass restoration is achieved 18 to 24 months after the Sediment Tubes are initially placed into the propeller scar or blowout area.


Simple project outline:


1. Locate and Survey the required square footage of propeller scarring and vessel groundings

2. Return the injury sites to grade through the installation of Sediment Tubes (FKNMS PEIS 2.2.6)

3. Collect and Install Planting Units according to the NOAA protocols detailed in the FKNMS PEIS at both the propeller scarring and the vessel grounding sites. (as required)


Community Involvement:

In order to bring more awareness and provide community involvement in this project, instructors from the University of South Florida (St. Petersburg campus) will be engaged to include marine biology students for the restoration activities. These students will receive hands-on experience and training regarding seagrass restoration activities. It is expected that 10 students will be engaged for 3 days each, during the restoration activities of filling and placing sediment tubes. The students will be volunteers for The Ocean Foundation and will receive community service recognition.