Article and photos by Kendra Shafer
St. Marys Riverkeeper
As the tide crept higher and higher, undergraduate students from the University of North Florida's Coastal and Marine Biology Program hustled to install their crab trap structures along the mud-slick shoreline. The students joined forces early Saturday morning with volunteers from the St. Marys Riverkeeper (SMRK) to plant beat-up old crab traps into the surf, with the understanding that they will appear as dream palaces to oysters.
In all, arrays of 70 crab traps were added to the living shoreline along the Amelia River at Fernandina Beach’s Old Town, completing a project that began with an initial crab trap reef in 2019. The Amelia River is the mouth of the St. Marys River, which begins in the Okefenokee Swamp in Georgia and makes a 130-mile path to the Atlantic Ocean.
“We used reclaimed crab traps filled with oyster shells to rebuild a reef offshore,” said St. Marys Riverkeeper Anna Laws. “The first group of traps has held together quite well over two years and shown significant oyster growth. Now, we are taking what we have learned and adding a line of structures to act as a wave break. We also have designated specific traps for a student study.”
The shoreline was lively at sunrise as the students and Amelia Island Sailing Club volunteers carried traps to the coast, wired them together and secured them in the proper locations. Fifteen students listened closely through the misty salt wind to the directions of their instructor, UNF Biology Professor Kelly Smith.
“It was an excellent learning experience for them,” Smith said. “They get a lot out of seeing the challenges of setting up an experiment in low tide.” Her students will be comparing two types of structures, one using cemented oyster shells and one using loose shells, to see which recruits the most new oysters over time, she said. Some UNF Geography and GIS students of Dr. Chris Baynard also participated, adding a high tech element to the morning with their drone flying overhead.
Living shorelines are growing in popularity in coastal states as an option to traditional “hardened” shorelines, such as sea walls. Many living shorelines consist primarily of stacks of net bags of oyster shells, creating an extension of the shoreline when combined with native plants.
When the first set of crab traps were installed at the Old Town Living Shoreline in 2019, SMRK was fortunate to have the assistance of Dan “the Oysterman” DeGuire, a former commercial oysterman who died in 2020. He used crab traps to grow oysters for years. They obtained the traps from a non-profit organization that collected them rather than letting them go into a landfill.
“It was a kind of recyclable thing to take these old traps and turn them into something useful,” according to Rick Frey, DeGuire’s friend and founder of the St. Marys Riverkeeper. “Also, it creates a structure that the oysters would cling to much easier and much quicker.”
• Creates a vegetated buffer that absorbs and disperses wave energy thereby reducing erosion
• Allows for animal access between upland and aquatic habitats
• Mimics natural shoreline dynamics
• Provides alternatives to the construction of rock revetments and bulkheads for erosion control
• Can be equal to or less expensive than structures such as bulkheads and rock revetments
• Preserves, creates, or maintains habitat for aquatic plants and animals
• Restores critical feeding and nursery habitat for fish
• Can trap and retain land runoff containing nutrients and pollutants
List provided by GADNR
UNF Students at low tide.