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August 22, 2019

This page last modified:
April 06, 2001

Volume 2, No. 1
Summer 1999

Boating Impacts to Local Seagrass Beds

A flight over the shallows of Florida Bay or the Keys will almost surely reveal a labyrinth of long, white sandy prop scars within the seagrass beds below.  When a boat propeller cuts into a seagrass meadow, it can leave a scar in its wake that may take several years to fully heal, if ever.  Many boat operators do not realize that repeated injuries to the same area affects the integrity of the habitat by actually breaking it into smaller, disconnected "islands".  If enough damage occurs to a single meadow, this valuable resource may be destroyed and along with it the important ecological functions it serves.  Even water circulation patterns can change when multiple scars combine to form a small channel through the seagrass bed.

Because many seagrass inhabitants are hidden between the blades, the diversity of this community may not be readily apparent to the boater or even the snorkeler.  Yet, a few passes with a mesh dip-net through the seagrass produces a variety of shrimp, crabs, snails, clams, and fish.  Seagrass habitats are also important to the commercial fisheries in Monroe County.  Spiny lobsters forage in them at night and juvenile pink shrimp inhabit Florida Bay seagrass meadows before migrating to the Dry Tortugas harvesting grounds.  In 1997, the commercial harvest for fish and crustacean species dependent upon seagrasses totaled 48.5 million dollars in Monroe County alone.

There are many other reasons for keeping your boat's bottom off of bay's bottom.  Propeller replacements, engine repairs and towing fees associated with boat groundings cost operators millions each year.  In addition, legal and civil fines can be leveed to mitigate damage done to the resource by the boat propeller and hull.

What is the extent of this problem in south Florida and the Florida Keys?  According to a 1995 Florida Department of Environmental Protection aerial survey, 30,000 acres of seagrass show signs of propeller scar damage.  In fact, there is scarring on virtually every shallow grassbed in the area.

What are local resource agencies doing to make people more aware of their boating impacts on seagrass communities?  In May 1997, the Florida Bay Education Project, Everglades National Park and the Florida Keys National Marine Sanctuary sponsored the "Seagrass Summit" which brought together resource managers, scientists, park rangers, and concerned citizens to discuss this issue.  From the Summit meeting, which was attended by nearly 100 people, an action group known as the Seagrass Summit Outreach Partnership was formed.  Members of the partnership recently launched a radio and newspaper campaign designed to educate people about shallow water boating techniques.  Free written materials and video tapes on the subject are also available and can be obtained by contacting the Education Project office or the Florida Keys National Marine Sanctuary.

Seagrass Outreach Partnership Agencies

Education Project Advisory Committee

The Florida Bay Education Project Advisory Committee formed last year to provide input for the Education Project.  Establishing advisory committees is a long standing tradition of the Florida Cooperative Extension Service/Florida Sea Grant. The committee currently has six members who have dedicated their time and energy to shaping the education and outreach effort.  They include:  Brian Keller, The Nature Conservancy;  Laura Engleby, Keys Educator and Marine Mammal Expert;  Toni Dufficy, Everglades National Park;  Dawn Welcher, NOAA Atlantic Oceanographic and Meteorological Lab;  Amy Knowles, Florida Keys Fishing Expert;  and Rosemary Hegberg, International Gamefish Association.  Their collective expertise will aid Sea Grant in finding innovative and effective ways to share research information about Florida Bay.

Science Program Website

A wide spectrum of information about the Science Program for Florida Bay and Adjacent Marine Systems is available on the program website maintained by NOAA/AOML.  This site supports an archive of critical documents and reports, including the Florida Bay Strategic Science Plan and reviews of the Oversight Panel.  Links are provided to metadata, research programs of cooperating agencies and associated university research teams, and to the Florida Bay Education Project home page which features project profiles summarizing recent findings from bay research projects.

Recent additions to the website include:

  • the PMC's comments on the draft Restudy Report;
  • predictive models for Florida Bay, the Florida Keys, and Southwest Coast;
  • the results from Hurricane George's workshop;
  • a summary report from the Seagrass Research Team about the seagrass workshop;
  • information about the next Florida Bay Science Conference;
  • the 1998 Science Conference Abstracts (partial compilation);
  • a summary report from the Physical Science Research Team about the March 1999 workshop;
  • Florida Bay Project Profiles.

The Florida Bay Education Project is an archived site. For more information go to NOAA's South Florida Ecosystem Education Project at