Scientists with the "Southwest Florida Water Management District's ":http://www.swfwmd.state.fl.us/ "Surface Water Improvement and Management (SWIM) Program":http://www.swfwmd.state.fl.us/projects/swim/ released the results of the 2012 seagrass mapping study showing a 5.3 percent increase in seagrass coverage in Tampa Bay. This is the fourth consecutive survey to show increases for the Tampa Bay system. The study also shows gains in Lemon Bay and Charlotte Harbor. The District maps seagrass in five estuaries spanning the five coastal counties of Pinellas, Hillsborough, Manatee, Sarasota, and Charlotte.
The results show Tampa Bay gained 1,745 acres of seagrass between 2010 and 2012. Tampa Bay now supports 34,642 acres of seagrass beds, the largest amount of seagrass measured since the 1950's. The steady increase in seagrass since 2006 has brought the system closer to reaching the Tampa Bay Estuary Program's goal of 38,000 acres bay wide. Charlotte Harbor gained 804 acres, a 4.4 percent gain while the smaller Lemon Bay system gained 67 acres, a 2.2 percent increase.
Sarasota Bay documented a one percent decrease in seagrass cover. The St. Joseph's Sound/Clearwater Harbor system showed a decrease of less than two percent; however both are considered sustainable and stable seagrass resources. According to Kris Kaufman, a staff environmental scientist for the District, a change in mapped seagrass cover of less than two percent can be due to the accuracy of mapping methods or simply natural variability in seagrass.
"Seagrasses can be gained or lost due to changes in the environment beyond our control," said Kaufman. "For example, heavy rainfall can bring excess freshwater runoff to the bays and affect water quality."
Documenting the extent of seagrass and how it changes overtime is a valuable tool for scientists throughout the state of 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 six 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.
The results show Tampa Bay gained 1,745 acres of seagrass between 2010 and 2012. Tampa Bay now supports 34,642 acres of seagrass beds, the largest amount of seagrass measured since the 1950's. The steady increase in seagrass since 2006 has brought the system closer to reaching the Tampa Bay Estuary Program's goal of 38,000 acres bay wide. Charlotte Harbor gained 804 acres, a 4.4 percent gain while the smaller Lemon Bay system gained 67 acres, a 2.2 percent increase.
Sarasota Bay documented a one percent decrease in seagrass cover. The St. Joseph's Sound/Clearwater Harbor system showed a decrease of less than two percent; however both are considered sustainable and stable seagrass resources. According to Kris Kaufman, a staff environmental scientist for the District, a change in mapped seagrass cover of less than two percent can be due to the accuracy of mapping methods or simply natural variability in seagrass.
"Seagrasses can be gained or lost due to changes in the environment beyond our control," said Kaufman. "For example, heavy rainfall can bring excess freshwater runoff to the bays and affect water quality."
Documenting the extent of seagrass and how it changes overtime is a valuable tool for scientists throughout the state of 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 six 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.