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Ali Leggett

Publications and source records attributed to Ali Leggett.

2 recordsLinked to original sources

Statewide summary for Mississippi

The Mississippi coastline is 113 linear kilometers (70 miles) long and its estuaries cover approximately 594 km (369 mi; Figure 1) (Handley and others, 2007). It has a man-made sand beach 43.5 km (27 mi) long and 595.5 km (370 mi) of shoreline (Klein and others, b., 1998). The Mississippi Sound extends across the coastal waters of the State and encompasses 175,412 ha (433,443 acres). It is bordered by the Mississippi coast; Mobile Bay, Ala.; the Gulf Islands National Seashore barrier islands; and Lake Borgne, La. The watersheds and drainages feeding into Mississippi Sound, excluding tidal exchange from the Gulf of Mexico, include Lake Borgne, Pearl River, Jourdan River, Wolf River, Biloxi River, Tchoutacabouffa River, Pascagoula River, and Mobile Bay. The Pascagoula River is one of the last undammed rivers in the continental U.S. and the only undammed river flowing into the Gulf of Mexico. Freshwater inflow into Mississippi Sound, excluding that from Mobile Bay, averages 882.4 m 3 per second (30,806 ft 3 per second). The Mississippi coastal zone contains approximately one-third of the State’s 120 ecological communities (Klein and others, a., 1998). Regional land use includes silviculture, agriculture, and urban development, including several coastal casinos. Commercial shipping, shipbuilding, phosphate rock refinement, and electric power generation companies include some of the industrial complexes found along the Mississippi coast. The three counties found along the Mississippi coast, Hancock, Harrison, and Jackson Counties, had a total population of 370,702 as of 2010, constituting 12.5 percent of the State’s population (U.S. Census Bureau, 2010). These counties cover over 160.9 km (100 mi) of coastline and are one of the fastest growing regions in the state (Klein and others, b., 1998). The casino industry, military installations, trade, and manufacturing provide most jobs in coastal Mississippi. Two major deep-water ports exist in coastal Mississippi. Recreation and tourism have a significant impact on Mississippi’s economy as well, annually attracting approximately 1.8 million visitors to the coast and generating approximately \$3.5 billion statewide, about one-third of which comes from coastal tourism. Ninety percent of the coastal tourism expenditures come from recreational boating and related industries. Marine recreational fishing generates more than \$50 million annually, with approximately 280,000 participants, more than a million recreational fishing expeditions, and over 40,000 resident saltwater sportfishing licenses sold each year. More than one-fourth of the anglers fishing in coastal Mississippi are tourists. Landings of shrimp, crabs, oysters, and finfish equal approximately 99.8 million kg (220 million lbs) of seafood annually. The entire seafood industry in coastal Mississippi, including processing of seafood caught in other Gulf States, generates approximately \$450 million per year.

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Mississippi Sound

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 km 2 (113 mi 2 ) large with a watershed of 259 km 2 (100 mi 2 ) and 44 km 2 (17 mi 2 ) 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.

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