CHAPTER IV: WILDLIFE HABITATS FOR MISSISSIPPI’S SGCN,
THREATS AND CONSERVATION ACTIONS^276Alabama Continental Shelf. The studies defined environmental character, affects of the Loop current,
complex species-environment relationships, species distribution and major fish and shrimp assemblages.
Total fishes of northern Gulf of Mexico excluding the southern Florida reef habitats number around
1,200 species; almost 400 species are found within the Mississippi - Alabama Continental Shelf. The
reef areas attract a large number and variety of fishes.
Unfortunately, marine areas are losing some of their productivity because of the loss of tidal marsh
habitats and overfishing. The small area of reef habitat and the long time required for many commercial
reef fish to reach maturity makes overfishing a problem. The soft bottom areas are also vulnerable to
overfishing. In addition, oil spills and other pollutants that persist in the open seas decrease the quality
of marine habitats.
During the 1970s and 1980s scientists at Dauphin Island Sea Lab found small, isolated patches of lag
deposits composed of shell and rock gravel that that occasionally included pebble to cobble sized
sandstone and siderite clasts. These hard bottoms within territorial waters of Mississippi as well as those
in Alabama were continually in burial-exhuming cycles, exposed and covered up and were particularly
influenced by tropical and winter storm events. There is no significant hard bottom in Mississippi
territorial waters.
15.1 Marine Habitats (Smooth Bottoms)
Value to SGCN - 28
Rank - 12th of 17 Marine, Estuarine and Estuarine Fringe Systems
DESCRIPTION
A large diversity of species inhabit the marine waters and reside in or on the bottom substrates. Over
370 species of fish and an abundance of mollusks, polychaetes, crustaceans and echinoderms, among
others, can be found. The prodelta fan of soft sedimentary mud extends eastward from the Birdsfoot
Delta of the Mississippi River. It is a zone of sedimentation that has smothered the development of reefs
in the western part of the region. Benthic creatures such as urchins are found in abundance on the fan.
LOCATION, SIZE, CONDITION AND CONSERVATION STATUS
NGM
For the purposes of the CWCS, marine habitats only extend to the
state jurisdictional limit of three miles beyond the outer shores of
the barrier island chain. This stretch of marine habitat forms the
upper shore face where sediments are larger grained and well
sorted. In deeper water below the breaker zone, the sediments are
Range of Maritime Habitats (Smooth Bottoms) 15.1 Marine Habitats (Smooth Bottoms)