In less than 30 years, 3,000-year-old oyster reefs off Florida’s Big Bend coastline have declined by 88 percent, according to University of Florida/IFAS researchers. For residents who depend on the fishing grounds and other coastal resources protected by these reefs, it’s a worrying trend. Now, with an award from the National Fish and Wildlife Foundation’s Gulf Environmental Benefit Fund, a UF/IFAS research team will work to restore these shrinking oyster reefs and help coastal ecosystems and economies become more resilient in the face of climate change and rising sea levels. The “Recovery and Resilience of Oyster Reefs in the Big Bend of Florida” project will target the Lone Cabbage oyster reef in the Suwannee Sound. The UF/IFAS team plans to restore up to 32 acres (encompassing about 3 linear miles) of reef.
Peter Frederick and Bill Pine who are a part of the UF/IFAS Department of Wildlife Ecology and Conservation, and Leslie Sturmer with the IFAS Extension, are the lead investigators on the grant. Their research shows that the decline of oysters in the Big Bend region is due to increasing salinity levels in Suwannee Sound, resulting from reduced freshwater flows of the Suwannee River. Oysters need intermediate salinities for protection from predators and parasites, and high salinities cause oyster reef die offs. As oyster reefs die off and lose elevation, salinity rises because of a lack of freshwater retention in the estuary.
The UF/IFAS project seeks to break this cycle by building up the degraded reef and retaining freshwater in the estuary, thus improving oyster recruitment. To do that, researchers will install limestone boulders covered in a layer of oyster and clam shell, materials that readily attract new oysters.
To learn more about this project, visit this article.
Physical damage to seagrasses via propeller/anchor scarring and blow-holes from vessels running aground is an ongoing problem in Florida and natural recovery from physical damage can exceed ten years. Over time, erosion and scouring in scarred areas can result in reduced resilience of the seagrasses to other stressors and lead to loss of seagrasses. Propeller scarring is a wholly preventable stressor to seagrasses and reducing and reversing this impact can lead to increased seagrass resilience to other stressors, secure ecosystem services, and help improve the ecological sustainability of the tourism activities that are vital to the coastal counties in this region.
To learn more about Seagrass Protection efforts at NCBS, or how you can get involved, go to https://ncbs.ifas.ufl.edu/be-seagrass-safe/
What is a “Living Shoreline”? The National Oceanographic and Atmospheric Administration (NOAA) defines a living shoreline as “a shoreline management practice that provides erosion control benefits; protects, restores, or enhances natural shoreline habitat; and maintains coastal processes through the strategic placement of plants, stone, sand fill, and other structural organic materials (e.g. biologs, oyster reefs, etc).” The basic idea is that erosion can be halted and reversed by restoring natural ecosystems such as marsh vegetation and oyster reefs in a strategic (engineered) way. A living shoreline can retain coastal sediments locally and adapt to changes in water levels via natural processes, unlike a seawall or other “hardened shoreline”.
To learn more about the Living Shoreline Project go to https://ncbs.ifas.ufl.edu/extension/dealing-with-coastal-erosion/joe-rains-living-shoreline-project/
Alterations to Freshwater Flow
Estuaries are areas where the rivers meet the sea. Changes to quantity and quality of freshwater in coastal areas, therefore, can have a drastic impact on the ecology of our estuaries. NCBS researchers and collaborators are performing a host of projects to determine the impact of changes to river discharge on coastal ecosystems. These projects include how restoration efforts to areas such as oyster reefs can benefit coastal ecosystems and how reintroduction of large rivers into salt marshes can impact food webs along a range of restored marsh sites.
Climate Change and Other Disturbances
Numerous anthropogenic and natural stressors affect Gulf of Mexico estuaries. NCBS researchers are studying a variety of these disturbances and how they impact coastal ecology.
For example, rising temperatures have resulted in expansion of tropically-associated species such as Common Snook and red mangroves into the northern Gulf of Mexico. Other projects are focusing on the impact of oil spills, such as the 2010 Deepwater Horizon spill, on estuarine flora and fauna. The cumulative loss of biodiversity of coastal organisms, and the subsequent effects on food webs and restoration efforts, is also a focus.