Oyster Restoration Initiative

Whitney Laboratory has established an oyster restoration initiative in the area. Learn more about the program by reading below.

Frequently Asked Questions

Why are oysters important?

  • Oysters are keystone species on which other species depend.
  • They provide cover, habitat and food for more than 180 other species of marine life.
  • Oysters form bars and reefs that protect shorelines from erosion and storm surge.
  • Oysters are filter feeders, meaning that they clean the water by consuming phytoplankton (microalgae), bacteria and detritus.
  • One average-sized adult oyster can filter up to 50 gallons of water per day.
  • This filtration rate is a tremendous ecosystem service that strongly influences the environmental quality of estuaries.
  • Oyster reefs are feeding grounds for wading birds and many fish such as snapper, grouper and snook.
  • Oysters provide an important fishery for human consumption.

What threats are there to oysters?

Oyster reefs are vulnerable to:

  • Boat wakes, which damage the reefs
  • Pollution from development (storm water runoff)
  • Damage from anchoring
  • Freshwater floods
  • Diseases like Dermo (Perkinsus marinus) and MSK (Haplosporidium nelsoni), which cause mortality in oysters
  • Ocean acidification, which promotes the loss of calcium carbonate, weakening the shells and affecting reproduction and development

What is an oyster’s life cycle?

When oysters spawn, they release their sperm and eggs in the water. After fertilization, millions of eggs develop into a free-swimming larvae stage that lasts from two to three weeks (depending on water temperature), after which the larvae settle onto hard surfaces, preferably other oysters. At this point they are referred to as spat (less than 1 cm). Several spat may set on one oyster shell and remain there the rest of their lives. In Florida, adulthood is reached in about eight to 12 months, when they are ready to spawn. Mature oysters can spawn multiple times a year for many years.

What is community oyster gardening?

Community oyster gardening is a citizen science initiative in which community members with a saltwater dock volunteer their time to grow oysters for oyster restoration projects.

These citizen scientists hang two oyster habitats from their dock, maintain the habitats by pulling them once a week from the water, rinse them to remove any fouling and/or predators and record the water quality data at their sites.

How does an oyster gardener get oysters?

Oyster gardeners receive their ”seed” or “spat” on recycled oyster shell. These baby oysters are produced in our hatchery at the Whitney Lab. Here is how we do it: local oysters are spawned at the hatchery and their larvae reared for about two weeks. At the end of the free‐swimming larval phase, larval oysters are ready to set (attach) to a substrate. At this point we introduced clean recycled oyster shell and the larvae attach to the shells and undergo metamorphosis. We then move the “seeded” shells to our nursery for further growth until they are ready to be picked up by the gardeners.

How does an oyster gardener get started?

First, to become an oyster gardener, you must own a dock in a salty waterway with tidal flow and see evidence of oysters growing naturally nearby. Then, you must attend a two‐hour workshop to learn about the Oyster Restoration Program and get trained on how to maintain the habitats and record important data.

What is expected of an oyster gardener?

An Oyster Gardener will need to set aside approximately two hours per week to do maintenance on their habitats and record data.

If an oyster gardener will be away for two or more weeks, then they should recruit an “oyster buddy” to fill in while they’re gone. Oyster buddies must also attend a two‐hour workshop.

An oyster gardener can expect to keep their habitats approximately eight to 10 months and will be notified by the Whitney Lab when it’s time to return them for use in oyster reef restoration projects.

Are oyster gardeners allowed to eat the oysters?

No, the oysters will be used to restore oyster reefs. 

What are community oyster reef enhancement (CORE) modules?

The modules are lightweight, easy to produce, plastic-free structures constructed from concrete and an organic mix (wood chips and burlap) with partially embedded recycled oyster shells. They are structurally stable and provide abundant microhabitats for wild baby oysters (spat) to settle on and for diverse reef organisms. Each module contains ten vertically oriented oyster shells, measures 11×14 inches, and weighs about six to eight pounds.

Why do we use CORE modules?

  • To reduce wave action and prevent shoreline erosion
  • To enhance oyster populations by providing new oyster reef habitat
  • To promote biological diversity and enhance local fisheries

What are other benefits of CORE modules?

  • As the modules develop into mature oyster reefs, the resiliency of the restored areas will improve, allowing the sites to withstand the effects of sea level rise and of increased storm frequency caused by climate change.
  • Restored oyster reefs provide important forage and refuge habitat for shrimp, crabs, clams, snails and worms, and many species of marine fish. They also encourage recruitment of natural vegetation such as mangroves and marsh grasses, further increasing biodiversity in our estuary.

Three critical shoreline areas were identified in the local waters of the Matanzas River Estuary in Marineland, Fla. These areas were particularly vulnerable to erosion from boat wake exposure, wind‐driven currents/waves and storms as well as sea level rise. The CORE modules were deployed intertidally in rectangular arrays to maximize wave attenuation according to each site’s topography and exposure.

How did CORE modules come about?

Oyster reef restoration efforts in Florida often utilize non-biodegradable materials such as plastics, thereby contributing to the detrimental accumulation of plastics in the environment. Recognizing the need to restore the degraded shoreline habitats of the Town of Marineland in an environmentally responsible way and engage local community volunteers, we designed the modules to be:

  • Environmentally friendly: the cement mixture is biodegradable and plastic-free, and the oyster shells are recycled from restaurants
  • Hold up to the natural elements long enough (four to six years) to allow naturally occurring spat to attach and grow into fully developed reefs
  • Be easily constructed so that volunteers of all ages can participate
  • Light weight and small for easy handling

Results to date have shown that after four months of deployment, modules can successfully recruit between 150 and 200 oyster spat each.

The Florida Coastal Management Program funded this project with a Grant from the NOAA Office of Ocean and Coastal Resource Management awarded under the Coastal Zone Management Act. Completed June 2017.

Funded by Florida DEP, The Town of Marineland and the St. Augustine Rotary Club. 

How can you help?