The Effectiveness of Shell Bag Restoration in Enhancing Salt Marsh Expansion in Coastal Georgia

Salt marshes are intertidal ecosystems that provide valuable services like wave attenuation, nutrient cycling, and carbon sequestration. Unfortunately, due to a combination of factors linked to global climate warming and increased coastal development, expanses of salt marshes are being lost worldwide. This has prompted coastal land managers to seek effective techniques to enhance salt marsh growth with changing environmental conditions. We examine how restoration of fringe oyster reefs, a commonly used technique to increase sediment accretion and erosion control in salt marshes, affects marsh migration and area change over time. Salt marsh vegetation movement was determined through analysis of aerial imagery collected by unmanned aerial vehicle (UAV) surveying before and in the months following restoration at a salt marsh island in Liberty County, GA, USA that underwent oyster reef restoration in September 2023 at three sites, each spanning ~25 m of shoreline. Results after one year showed all restoration sites experienced continued growth at greater rates than nearby unrestored control sites, despite environmental differences between sites. Our results provide evidence that oyster reef restoration may be a viable method for mitigating the loss of salt marshes in coastal Georgia.