Originally published in Space Coast Living Magazine
The Liver In The River. Indian River Lagoon Oyster and Clam Projects
A single oyster can filter 30-50 gallons of polluted water in a day, a tiny clam as much as 25 gallons. So say scientists working to clean up the Indian River Lagoon in Brevard County. Think of what millions of those bi-valves can do for water quality in the lagoon. Not convinced? If you have a fish tank, next time it starts to get grungy put a couple live oysters in it. Rather quickly the water becomes clear again.
To be sure oysters and clams can’t do it all themselves, but they are probably the most cost effective way to help clean the polluted lagoon waters in Brevard County.
Working with grants from the Brevard sales tax devoted to the lagoon cleanup, the Brevard Zoo is transplanting millions of oyster shells into the lagoon, forming oyster reefs along shorelines. The shells become home to oyster embryo in the water. They begin to work their magic when they mature.
The University of Florida Whitney Lab in St. Augustine is spearheading the clams work, and has already dumped over ten million “super clams” into the lagoon.
Olivia Escandell, who heads up the oyster project for the zoo, calls the bi-valves “the liver in the river”.
The oyster work has been going on since 2014, but really picked up steam when Brevard’s lagoon cleanup sales tax kicked in four years ago. The oyster project qualifies for funding, about $45-thousand a year. The work is governed by permits from the Florida Department of Environmental Protection.
Most of the reef building occurs from March to October, which Escandell says offers “the best chance for baby oysters to colonize the reef”.
The oyster shells are donated by 20 restaurants in Brevard County, and Southeastern Seaproducts of Melbourne, a commercial oyster shucking house. The restaurants save shells from their oyster meals, and volunteers pick them up periodically. The process gave birth to the name of the project, “Shuck and Share”. About 27,000 pounds of shells are collected every month.
The shells are quarantined for three months to rid them of any organic matter, then packaged in mesh bags that are deposited in the shallows along the lagoon shoreline. The reef building is mostly done by volunteers...individuals, civic organizations, college clubs, and business teams. It’s hot, dirty work. Everybody gets wet, but there are lots of laughs and smiles of satisfaction. If you’re interested in volunteering, go to restoreourshores.org and click on the Volunteer tab.
So far the oyster reefs cover over a mile and a half of the lagoon shoreline, with the ultimate goal of 20 miles, at which point Escandell says they will have a noticeable impact on water quality.
The introduction of clams to the lagoon started in 2018. The University of Florida Whitney Lab located surviving clams in the lagoon that were the only surviving remnants of once
widespread clam colonies. Poor water quality killed off most of the clam population, leading the few survivors to be dubbed Darwinian “natural selection” super clams by project leader Dr. Todd Osborne, who is known as the Clam Master.
“Reintroducing clams, and especially those clams adapted to the way (the lagoon) is now, should be a huge step in the right direction for improving our water quality,” says Osborne.
University researchers used the super clams to breed huge colonies of clams that are relocated into the lagoon at seven different locations in Brevard County. To date over ten million clams have been transplanted into the lagoon, and are expected to breed and expand the population on their own.
According to Dr. Osborne, “We have found clam larva in the lagoon so we know it’s working. They’re doing it. They’re reproducing.” Another positive says Osborne is the clams survived the lagoon’s most recent algae bloom.
Funding for the clam project comes from grants from a variety of sources, and the budget next year is approaching a million dollars. “It costs us ten cents a clam,” says Osborne. That works out to $100-thousand for a million clams, and next year they plan to place eight to ten million more clams in the lagoon. Most of that budget pays for staff time, boats, and clam transportation in refrigerated trucks from the breeding labs in St. Augustine.
For the future Osborne says they intend to expand the clam project to other lagoon sites in the Fort Pierce and Port St. Lucie areas.
Osborne calls the clams and oysters just one treatment for “a large disease.” Pollution of the lagoon comes from many different sources and “there is not one particular solution.”