COSM

Georgia Salt Marshes

Marsh Habitat

The salt cord grass marshes of the Georgia Coast are amongst the most luxuriant and best protected in the world. Vegetated by Spartina, Salicornia, and Juncus the marsh meadows present a nearly level surface built at high tide level by buffering tidal flow and allowing settlement of suspended silt and mud carried in the turbid coastal waters. The nearly level grassy surface of the marsh is constantly eroded by meandering tidal rivers and creeks depositing marine point bars, which are floored by shell-beds as they wander back and forth. Mud barrens are interspersed with the grass throughout the marsh, which is approximately 8.0 km (5 mi) wide along the Georgia Coast.

Seaside Marsh at St. Catherines flooded by a high Spring Tide and Nor'easter, September 9, 2006.

Seaside Marsh at St. Catherines flooded by a high Spring Tide and Nor’easter, September 9, 2006.

A mud flat along side a marsh pond being foraged by an army of Fiddler Crabs.

A mud flat along side a marsh pond being foraged by an army of Fiddler Crabs.

Fiddler Crabs constantly rework the marsh mud and extract organics from it.

Fiddler Crabs constantly rework the marsh mud and extract organics from it.

Oyster bioherms often occur in relict marsh deposits.
Oyster bioherms often occur in relict marsh deposits.

Relict marsh is exposed as North Beach Erodes. Seaside marsh lies to the left over the berm of Seaside Spit.

Relict marsh is exposed as North Beach Erodes. Seaside marsh lies to the left over the berm of Seaside Spit.

The modern marsh hosts tidal creeks and mud flat flora and fauna.

The modern marsh hosts tidal creeks and mud flat flora and fauna.

The vegetated tidal mud flats are home to numerous invertebrates, amongst which are the Northern Quahog, Atlantic Ribbed Mussel,Marsh Periwinkle, tidal creek margins host masses of the American Oyster and a host of crevice dwellers in these small oyster reefs (including the Stone Crab, Oyster Drill, and numerous worms). Edges of mud barrens, banks of tidal creeks, and the grassy mud flats are inhabited by millions of small, burrowing crabs called Fiddler Crabs.

Last updated: 7/12/2016

Sea Turtle Program at St. Catherines Island • (912) 478-1744 • jgaskin@georgiasouthern.edu