Some 160 kilometers of oyster reefs are being built along the Alabama coast to help mitigate effects of the 2010 BP oil spill. In front of one barrier island, concrete reef balls and bags filled with oyster shells now absorb wave action that had chewed a foot-high edge on the island’s marshy shoreline. Accumulating sediment is extending the marsh, and scientists report oyster recruitment and increased bird and fish activity around the sites.
“Every mile of reef we put in protects about 10 acres of coastal habitat,” says Judy Haner, director of marine and freshwater programs for The Nature Conservancy in Alabama, which is collaborating on the reefs with the Alabama Coastal Foundation, Mobile Baykeeper and The Ocean Foundation. “This project has great potential to be replicated and used to advance large-scale restoration efforts across the Gulf of Mexico.”
Research shows that oyster reefs protect and stabilize shoreline, enhance estuary productivity, capture suspended sediment and improve water quality. During the past 100 years nearly 90 percent of natural oyster reefs in the Gulf of Mexico have been removed, the shell used for roadbeds and construction, or lost due to overfishing and declining water quality. This loss left the entire marine ecosystem more vulnerable to damage from the five-million-barrel Gulf oil spill in 2010. Oysters—sedentary organisms particularly susceptible to harm from oil and dispersant exposure—were also directly affected, with decreased recruitment of oyster larvae throughout the northern Gulf in 2010, 2011 and the fall of 2012. Building oyster reefs will not only help restore those losses, but make the Gulf system as a whole healthier and more resilient.
Read the full story at the Scientific American>>