JANIE GOULD

Twenty-four buoys designed to warn power boaters about fragile seagrasses in a particularly shallow part of the Indian River Lagoon were expected to be installed by the end of October.

The buoys will encircle the Moorings Flats, a square mile of water that’s less than a foot deep in spots,   between the Moorings Channel and Round Island Channel. Local architect Paul Dritenbas, who first fished the flats when he was 6 years old, describes them as a natural aquarium teeming with fish, manatees and other marine life, all nurtured by abundant seagrass. The water is cleansed twice a day by infusions of sea water from the Fort Pierce Inlet. It can be as shallow as six inches, causing inexperienced boaters to run aground and wreak havoc on seagrass beds.

“As a part-time fishing guide, I kept seeing more and more prop (propeller) scars in the flats,” he said,  “and they can take from two to 20 years to recover, if they ever do. When the prop hits the seagrasses, it hits the deep horizontal roots.”

“A lot of the people who ground their vessel just don’t know where they are,” he said. “At low tide, the grasses here are sometimes out of the water, that’s how shallow it is. Boaters will be racing across the river and the next thing you know, they run aground. They go 75 or 80 feet and stop. They’re stuck. Then they try to put the boat in reverse, and that’s why, at the end of every prop scar, there’s always a delta.”

Dritenbas has long been an active member of the Vero Beach Rotary Club and is a former president.  He created the Rotary Initiative for Submerged Seagrass Awareness, which raised about $18,000 to purchase and install the buoys. His Rotary Club, along with the Sunrise Rotary Club and the Indian River County Commission, collaborated to share the costs. Marine contractor David Foster, from Jupiter, were to install the buoys the last weekend of October, Dritenbas said.is

The buoys will be posted with warnings saying “Caution. Seagrass Area” and will be placed around the Moorings Flats at 600-foot intervals.

“This is an informational zone,” he said, “not a regulatory permit.”

Seagrasses in the flats provide sustenance for snook, black drum, mangrove snapper and many other resident fish, along with migratory fish such as mullet.

“This is the most prolific sea trout spawning area in the whole lagoon,” Dritenbas said. “Sea trout spawning sounds like a heartbeat, and when they really get going it sounds like a stampede of buffalo.”

Keeping seagrass healthy in the Moorings Flats has become even more critical since grasses started disappearing in the lagoon north of the  17^th Street Bridge and into Brevard County.

Grant Gilmore, a founding scientist at Harbor Branch Oceanographic Institute and now senior scientist with Estuarine, Coastal and Ocean Science, Inc., took surveys and found virtually no seagrass remaining.  Researchers with ORCA, the Ocean Research and Conservation Association, are taking 10,000 sediment samples, from the Barber Bridge to the Wabasso Bridge,  in an effort to learn what happened to the seagrass.

Normally, an acre of seagrass produces 10,000 fish each year.

“Seagrass is the heart of the lagoon,” Dritenbas said. “They harbor all of the little fish.”

The disappearance of the seagrass has had other consequences:  With fewer small fish to feed on, sharks are moving close to shore in their search for food. Also, manatees and dolphins have migrated south in the lagoon in a search for seagrass.

“They’re looking for something to eat,” he said. “A manatee eats 150 pounds of seagrass a day, and that’s putting pressure on the seagrass habitat.”

It’s taken three years to get the buoy project approved and funded. The Florida Fish and Wildlife Commission, Florida Department of Environmental Protection, U.S. Army Corps of Engineers and Coast Guard were all involved, along with such local stakeholder as the county’s mosquito control department, Harbor Branch, the Indian River Land Trust, which acquired land along the shoreline for preservation, and Moorings homeowners.

Dritenbas said no one raised objections.

‘This is an educational zone, not a regulatory zones, and it will be first one,” he said. “It will be a model for all future informational zones, educational zones.”

There’s an oyster bed in the middle of the Moorings Flats. An oyster can purify 55 gallons a water each day, which allows light to penetrate deeper into the water and enhance photosynthesis. That, in turn, makes more seagrass grow.

Dritenbas says he hopes a graduate student, possibly from Harbor Branch, could do some follow up on the buoy project, to see how effective the buoys become in reducing damage from power boats in the Moorings Flats.

‘It’s the last living seagrass meadow in the lagoon,” he said. “It’s beautiful, and hopefully it will be there for the next 50 years, as it has been for the last 50 years for me. It’s a spectacular spot, and it needs to be preserved.”