SEBASTIAN — Oysters – they’re not just a menu item. Along with the high-tech, high cost methods through which experts hope to bring the endangered Indian River Lagoon back to health, the humble oyster can play a vital role as well simply by just doing what oysters do, as the Sebastian Natural Resources Board learned during its June 3 meeting.
Toby Jarman, of the Vero Beach Power Squadron, explained how the homely bivalve can play a vital role, through The Oyster Mat Project, currently under way via a partnership between the Power Squadron and the Rotary Club of Vero Beach Sunrise.
Oyster mats are designed to enhance existing oyster beds and, where no beds exist, to create oyster “reefs,” and the project leaders would love to reach their goal of 5,000 oyster mats.
The Sebastian City Council has expressed an interest in the project. Newly hired Environmental Specialist Cynthia Watson told Board members City Manager Joe Griffin had assigned her to the project and has made her available to support the Board as they explored it further.
Oysters, said Jarman, are considered to be a “keystone species” – one which, when introduced into an ecosystem, will support the life of that environment.
Oysters support the life of the lagoon environment because they are, Jarman said, “Mother Nature’s water filters” efficiently filtering pollutants out and clarifying the water.
Clear water lets the sunlight reach the lagoon’s bottom, allowing seagrass to grow. Seagrass provides a place for fish to spawn as well as a habitat for shrimp, crabs and other creatures which provide food for fish, which in turn provide food for birds, dolphins and on through the lagoon food chain.
In the local segment of the 156-mile long lagoon, “We have drastic decrease in wildlife, like cutting off a light switch,” Jarman said. The seagrass has died, robbing the fish, birds and mammals of their habitat and food sources. He held up a 16-by-16-inch black plastic mesh mat to which had been fastened, with black zip ties, 36 oysters shells, positioned vertically.
As the Board members passed the mat around, Jarman continued explaining the process. Hundreds of mats are assembled and then, “like grandmother’s patchwork quilt” they are fastened together (with more zipties) into a large mat, which is placed in the water near existing oyster beds, weighted down with sprinkler head protector “donuts.”
“Timing is everything” when placing the mats, said Jarman, because oysters reproduce only once a year, which in this area of the Indian River Lagoon is March. In only a matter of hours, the oysters’ egg and sperm produce a larvae, which immediately goes floating off until it either bumps into a seawall or a mooring ball or some other random object and latches on, or keeps going and dies or gets eaten – which is where the oyster mats come in.
Each vertical shell in the oyster mat acts as a sort of catcher’s mitt, stopping the larvae from zipping out into the water. Instead, they bump into the shiny inside of the oyster shell, latch on and become a “spat.” And the oyster bed grows, filtering more pollutants and clarifying more water, thus bringing the sunlight into the depths, allowing the seagrass to grow and the chain of aquatic life to renew.
Joining Jarman was Rotary President Paul Dritanbas, who is also a charter boat captain. Choosing the right location, somewhere protected from boat and human traffic, he said, is crucial to the program’s success. The mats must be out of the channel and away from wave action from boats, which can cause them to roll up, damaging the oysters. A shallow, tidal area is best, allowing the oysters to be exposed to the light and air for a while and submerged for a while, with the tides.
“A remote spoil island” would be ideal, Dritenbas said.
Jarman said the project is extremely labor intensive and requires lot of dedicated volunteers to put the mats together.
“You’ve got to have a strategy,” he stressed. He’s already been able to gather several volunteer groups and is especially excited about the kids from the Boys and Girls Club. “Students are a great resource, especially the high schools and juniors highs, where the students are required to have a service project. This is perfect for that!”
One high school student put the word out on Facebook and Twitter and “he brought 35 kids and got 100 mats done in one day.”
As word spreads, more and more groups want to assemble the mats and help the lagoon.
Dritenbas said that oyster mat project does require permits from both the Florida Department of Environmental Protection, and the Army Corps of Engineers.
The cost, not including labor and permit fees, is about $7.47 per 16×16” 36-shell mat, including donut anchors, or $7,470 for 1,000 mats. The oyster shells are out of the Gulf, said Dritenbas, trucked in by the fruit box load from a shucking plant in Louisiana and cost little to nothing.
Upon arrival, said Jarman, they are thoroughly rinsed in bleach to ensure they are clean and free of any bacteria or other substance that might have hitched a ride from the Gulf. There is a bit of a learning curve, as well, to ensure they are placed properly and fastened securely onto the mat. Jarman hopes to teach the process to people who can then teach other groups.
Dritenbas would like to see 5,000 mats assembled by next March, so they can be in place in time for the April oyster reproductive cycle.
Storage of the mats until then should not be a problem. The Rotary and Power Squadron have arranged storage for their mats and, Board Chairman Robin Graves noted, the City should have a location suitable to store mats as well.
Jarman provided the names of Harbor Branch oyster and seagrass experts who can provide information and told the Board the Power Squadron would be happy to help with training. Watson will investigate the project from the City’s perspective, including permitting and grant availability, and coordinate with the Board.
