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Mississippi Sound

January 1, 2012

The Mississippi Sound is the primary body of water off the Mississippi Coast, extending from Lake Borgne, La. in the west to Mobile Bay, Ala. in the east and bordered by the barrier islands--Cat, Ship, Horn, Petit Bois, and Dauphin Islands--of Gulf Islands National Seashore to the south (Figure 1). It encompasses an estuary 293 km2 (113 mi2) large with a watershed of 259 km2 (100 mi2) and 44 km2 (17 mi2) of tidal marsh (Klein and others, b., 1998). It is approximately 129 km (80 mi) long, 3 m (10 ft) deep, and varies in width from 7.2 to 22.5 km (4.5 to 14 mi) (Klein and others, a., 1998). Average tidal range is 0.6 m (1.96 ft), with local water depth and surface level fluctuations largely affected by wind (Klein and others, b., 1998). The climate is semitropical/subtropical with south-southeast winds at approximately 10.4 kph (6.5 mph).

Major rivers draining into Mississippi Sound, including the Pearl, Pascagoula, and Alabama Rivers, tend to carry high sediment loads (Klein and others, b., 1998). Inland fresh water drainage from these and other smaller rivers, as well as St. Louis and Biloxi Bays, create an estuarine environment in the Sound. Variable salinity levels can affect the productivity and survival of organisms living in the Sound, as well as economic and recreational activities. Predominate vegetation includes Juncus roemerianus (black needlerush) and Spartina alterniflora (smooth cordgrass). Shrimp, crab, oysters, and multiple species of finfish can be found in the waters of the Mississippi Sound.

Publication Year 2012
Title Mississippi Sound
Authors Lawrence R. Handley, Kathryn A. Spear, Ali Leggett, Cindy A. Thatcher
Publication Type Report
Publication Subtype Other Government Series
Index ID 70041778
Record Source USGS Publications Warehouse
USGS Organization National Wetlands Research Center