District Reports Consistent Seagrass Increases in Tampa Bay

News Release

Scientists with the Southwest Florida Water Management District's (District) Surface Water Improvement and Management, or SWIM program, released the results of its 2016 seagrass mapping study showing Tampa Bay now supports 41,655 acres of seagrass beds. This increase continues the success of the previous mapping efforts reported in 2015, supporting the largest amount of seagrass measured since the 1950s.

This increase in seagrass has surpassed the recovery goal of 38,000 acres bay wide, set 24 years ago by the Tampa Bay Estuary Program.

District scientists report a 3.4 percent increase in seagrass coverage in Tampa Bay, which totals 1,360 acres of seagrass between 2014 and 2016. This is the fifth consecutive survey to show increases for the Tampa Bay system.

The District maps seagrass in five estuaries spanning the five coastal counties of Pinellas, Hillsborough, Manatee, Sarasota, and Charlotte. Map results for the other four estuaries are also available.

Documenting the extent of seagrass and how it changes overtime is a valuable tool for scientists throughout Florida. Seagrasses are an important barometer of a bay's health because they require relatively clean water to flourish, thus they are sensitive to changes in water clarity and quality.

The District's maps are used as a tool for measuring and tracking biological integrity of estuaries as it relates to water quality conditions. Seagrass generally grows in waters less than 6 feet deep, but in the clear waters around Egmont and Anclote Keys it can be found in water 10 feet deep or more. The District began its formal seagrass mapping program in 1988. As part of the program, SWIM scientists assess seagrass in five Gulf coast estuaries. Every two years, maps are produced from aerial photographs and then verified for accuracy by conducting field surveys. The results are used to track trends in seagrass and to evaluate ongoing water quality improvement efforts