Oyster Reef Restoration
Good news for oyster reefs, the planet’s most imperiled marine habitat.
Along Florida’s coasts, oysters play a vitally-important role in supporting healthy estuaries. Oyster reefs provide multiple benefits, from providing habitat and food for wildlife, to filtering water, removing nitrogen, and stabilizing eroding coastlines. Oysters are also a favorite cuisine for people and Florida once had robust oyster fisheries in many areas throughout the state.
“Oysters are the quiet, unsung heroes of our estuaries, working hard every day to protect our coasts, clean our waters, feed and shelter fish, birds, crabs, shrimp and other wildlife,” said Anne Birch, marine program manager for The Nature Conservancy in Florida. “When we help to restore and conserve oyster habitat and support the fishery we’re also helping our estuaries and our coastal communities flourish.”
A healthy adult oyster can filter up to 50 gallons of water daily. Multiply that by hundreds of living oysters forming a reef and the water filtration service they provide can be significant, helping to cleanse our estuaries and support aquatic grasses and other plants that need light to survive. These plants, in turn, yield benefits like fish production and carbon storage, completing an invaluable cycle.
Healthy oyster reefs serve as natural buffers against rising sea tides and hurricanes by forming breakwaters that help protect shorelines and mangroves from erosion.
Oyster reefs also create economic value, bringing upwards of $10 million (dockside valuation) into Florida alone. “I can think of few other species that combine the ecological and economic benefits of being a species that creates habitat, and are also a fishery,” Birch said.
Oyster reefs have severely declined throughout their historical ranges all over the world. Today, oyster reefs are considered one of the planet’s most imperiled marine habitats. Over the last two centuries more than 85 percent of the world’s oyster reefs have been lost, and this statistic is echoed in most of Florida’s bays and estuaries. Florida’s Gulf of Mexico and Pensacola Bay regions are no exception, and The Conservancy is working to restore these critical ecosystems. Oyster reefs face a variety of threats including overharvesting, disease, pollution, and damage from boat traffic. Our oyster reef restoration efforts focus on areas where oysters were formerly prolific and will complement the commercial oyster reefs and industry that has been hit hard over the years.
We use a science-based approach to determine the best restoration method for each site, such as oyster bags, loose oyster shell, or other structures. Our international team of scientists share their experiences with different methods and discuss the pros and cons and successes or failures with one another and partners. It’s an excellent way to “go global” with a local project.
The Conservancy manages oyster restoration projects in several Florida systems, including the Charlotte Harbor Estuary in southwest Florida and Pensacola East Bay in the panhandle. We have received funding from the National Fish and Wildlife Foundation (NFWF) Gulf Environmental Benefit Fund, designated to remedy harm and reduce the risk of future harm to natural resources that were affected by the 2010 Deepwater Horizon oil spill. This NFWF funding will allow us to complete the design and installation of one of the largest oyster restoration efforts managed by TNC’s Florida chapter.
An essential step to understanding the success of any restoration project is to monitor its progress over time, to evaluate oyster populations and the attraction of additional species to the area. Results from our oyster reef project in Charlotte Harbor, where we tested three different methods, have been positive with all our restored reefs settled with juvenile oysters. NFWF will also fund post-construction monitoring of the Pensacola East Bay project to track the project’s success.
As we restore oysters it’s also necessary to understand the baseline condition of oysters in our bays and estuaries—where is oyster habitat, how much is there, and what is its condition, is it healthy or declining. Mapping existing reef habitat and its condition, combined with data on an estuary’s physical conditions (salinity, water quality, water depth, bay bottom sediment, etc.), gives us a much-needed analysis and understanding of restoration suitability—where is it best to restore oyster habitat today and into the future.
We are committed to restoring oyster reef habitat in coastal areas throughout Florida to reestablish the area’s critically important oyster populations and are grateful to our many partners and volunteers who work alongside us to make these projects possible.
“The health of our estuaries hangs in the balance,” Birch said. “The importance of restoring oyster reefs cannot be overemphasized. Managing our oyster resources requires a collaborative approach, working with fishermen and other users to figure out how a bay can flourish while supporting a sustainable wild harvest fishery, growing aquaculture businesses, and habitat restoration. It does not have to be an either-or option but rather how can we work together to ensure all needs are met.”