“Tampa Bay is one of very few estuaries in the world that is actually recovering,” according to Holly Greening, executive director of the Tampa Bay Estuary Program.
Speaking before the Florida Native Plant Society on Aug. 7, she attributed that success to people, regulatory agencies and local governments working together.
The result is an overall quality of water about the same as it was in the 1950s, Greening said.
The largest open-water estuary in the state, the bay covers some 400 square miles with an average depth of 12 feet.
Tampa Bay plays a major role in the local economy. There are 2.3 million people in its watershed (land that drains into a specific body of water), which runs from the spring-fed headwaters of the Hillsborough River south to the salty waters off Anna Maria Island. The Port of Tampa is one of the top ten in the United States.
But it hasn't always been a pretty picture.
Thirty to forty years ago, fish kills were common. Half of Tampa Bay's sea grasses and natural shoreline were lost; forty percent of the tidal marshes were destroyed.
Greening showed a photograph of “The Kitchen” near Gibsonton in Hillsborough County in the 1970s, which she called the “worst decade.” The shallow water haven was algae-covered, smelly and degraded. Television coverage brought national attention to the problem.
So what caused Tampa Bay's decline? The marine biologist identified several factors and a common pollutant: nitrogen. There was unrestricted dredging and filling, sewage was poorly treated, and storm water runoff and industrial discharge went untreated.
In 1991 the Tampa Bay Estuary Program brought together cities, counties and regulatory agencies to find out how to help Tampa Bay recover. Greening headed the organization.
Sea grass restoration was a priority, as those beds serve as a nursery for fish and invertebrates, as well as food for manatees. Studies promoted the implementation of nitrogen management policies. Industrial discharges were monitored and nutrient caps imposed; residential fertilizer restrictions were enacted; and stormwater was treated. Recovery resulted. As determined by aerial photographs, the sea grasses have responded to those measures.
In addition to sea grasses, other critical habitats were identified, including mangroves/salt marshes; sediments; mud flats; and hard bottoms, such as limestone and oyster beds.
While some areas were beyond saving, more than 5,000 acres of coastal habitat have been restored since 1995, Greening said.
“This is a remarkable place to work” because the community is willing to pull together, she added.
But serious challenges lie ahead, Greening said. One of the most difficult is sea level rise/climate change. Sea levels are rising an inch per decade, and experts have predicted a one to two meter rise by the next century.
Invasive plants and animals are another concern. Greening advocates protecting native and green areas through land-use regulations, and not just because it's better for wildlife. And using Florida-friendly and native plants helps reduce a source of nitrogen, which in excess can cause algal blooms that can kill fish.
“We need to look at every source of nitrogen,” Greening said.
“The next 20 years will require continued public/private collaboration on pollutant reduction actions; individual awareness and action; education; and long-term monitoring and research. Science and monitoring are real critical to figure out what works.”
But for now, the news is good. Further information about the Tampa Bay Estuary Program may be found at its website, www.tbep.org.
The Pinellas Chapter of the Florida Native Plant Society meets regularly at the Pinellas County Extension office, 12520 Ulmerton Road in Largo. Complimentary refreshments and a silent auction of native plants precede the program at 7 PM.
Open to the public, the Sept. 4 presentation will be a preview of their popular annual landscape tour.