Recovery of vegetated habitats on Horn Island, Mississippi, 1 northern Gulf of Mexico, in the initial five years following Hurricane Katrina

Lucas, Kelly; Carter, George

Barrier island ecosystems are dynamically driven by interactions among climatological, oceanographic, geological, hydrological, and biological processes. In the northern Gulf of Mexico, sudden alterations to barrier islands occur relatively often as a result of hurricanes. Barrier island vegetation is not only affected by storm impacts such as burial under sand overwash and direct removal of vegetation by erosion, but also by wind‐driven salt spray and flooding by saltwater tidal surge. This study utilized field surveys in conjunction with remotely‐sensed data to evaluate changes in vegetation composition and distribution on Horn Island, Mississippi, U. S. A., in the initial five years after Hurricane Katrina. The majority of habitat change occurred closer to the shoreline and in areas of sand overwash. As a percentage of pre‐island land area, beach habitat increased, while woodland and marsh decreased within 5 years after the storm. With respect to habitat‐type, areas of meadow, stable dune, inland pond and lagoon habitat remained relatively unchanged, although within‐habitat species composition was altered extensively in some locations. Despite an overall decrease in land area, island elevation generally increased in the initial 5 years following Katrina. Thus, cross‐shore sediment deposition and resulting vegetation changes, appear to provide a mechanism for Horn Island to build, possibly counteracting sea‐level rise and coastal subsidence.