Sea grass beds in what is known as the Spring Coast Watershed, which includes waters off Pasco, Hernando and Citrus counties, just got a report card from the Southwest Florida Water Management District, and the news is encouraging.
Overall, the region saw 8,500 acres of sea grass gains since 2016. Though there were segments of the aerial mapping survey that showed some grass losses in shallower water, they were minor and gains in deeper water more than made up for them.
The survey, which is conducted every four years, is divided between inshore waters and estuaries and offshore waters out to depths of about 25 feet, where sponges, coral and other growth is more predominant. Those types of growth are included in the sea grass survey, as just as important to the ecosystem and marine life.
The grass gains and losses are determined by a team of SWFWMD experts analyzing photographs of the Gulf and comparing visible grass beds with results from the previous mapping study. The current mapping is from photos taken in 2020.
The biggest gain in new grass acreage on a percentage basis was the offshore segment at Anclote in Pasco County. There was an increase of 1,326 acres of new growth, or 6,483 acres compared to 5,156 acres in the 2016, for a 25.7 percent gain. Waters off Aripeka saw a healthy increase of 4,709 acres to 79,028, or a 6.3 percent increase. Offshore waters west of the Cotee River segment edged up 1.1 percent, or 172 acres, to 15,213 acres.
Offshore growth off Weeki Wachee increased by just 35 acres, from 70,623 to 70,658, for a statistical no-change.
Inshore water across the board lost some acreage, but overall these sea grass beds were rated “stable.”
Weeki Wachee lost 235 acres of grass, or .6 percent of since 2016, while Aripeka is down 644 acres for a 1.4 percent loss. The Cotee River and Anclote segments lost 79 and 141 acres respectively for less than a 1 percent loss for both.
Though the inshore waters showed some losses, they are not worrisome to SWFWMD scientists.
“Overall the District sea grass maps show the extent of sea grass in the near-shore coastal waters off Hernando and Pasco counties were relatively stable between 2016 and 2020,” said Chris J. Anastasiou, chief water quality scientist with the SWFWMD and the sea grass mapping program lead.
Sea grass, sponges and coral is essential to the ecosystem and supports marine life, which is why the overall positive mapping results are welcome, particularly the large gains off Anclote and Aripeka.
“The 2020 maps revealed a significant expansion of these composite colonized sea grass areas in the offshore Anclote segment and offshore Aripeka segments,” he said. “These diverse habitats of sea grass, algae, sponges, and corals are a hallmark of the Springs Coast and very important to many both ecologically and economically important species of fish, crabs, shrimp, and oysters.”
The Spring Coast is so named because of the many freshwater springs that feed into the Gulf. The relative stability of the region’s sea grass meadows is owed to the fact that it’s relatively undeveloped compared to other parts of the state.
“The open water nature of the area, relatively low urban development, and expansive coastal wetlands all contribute to the region's stable sea grass habitats,” said Anastasiou.