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CHAPTER IV: WILDLIFE HABITATS FOR MISSISSIPPI’S SGCN,

THREATS AND CONSERVATION ACTIONS^278

regulations in important habitats/populations.

A Control exotic and invasive species (plant and animal).

A Provide public education about conservation of SGCN and/or their habitats.

A Encourage proper disposal and cleanup of waste and litter.

A Miscellaneous conservation actions as described: Contingency plan for oil/chemical spills

15.2 Hard Bottoms and Oceanic Reefs

„ Value to SGCN - 12
„ Rank - 15th of 17 Marine, Estuarine and Estuarine Fringe Systems

DESCRIPTION

A very small portion of the bottom of marine habitats within Mississippi’s jurisdictional waters is
composed of rock outcrops and consolidated features. These sections of the shelf are called reef and
inter-reef bottoms. The linear segments represent ancient shoreline ridges of cemented sand, shell and
gravel. Although the hard bottom habitats lie mostly east of the Mississippi coast, i.e. south of Mobile
Bay and around Desoto Canyon, some calcareous outcrops occur south of Biloxi in 60 feet of water and
along most of the continental shelf edge within the 150 to 300 foot depth. The linear reef and inter-reef
sections along the shelf edge are part of a system of reefs that ring the Gulf of Mexico. The reefs contain
topographic features of irregular small depressions and mounts reaching to 30 feet in height. They serve
as important spawning areas for many fish species and support commercial and recreational fisheries.
The reefs contain an intriguing list of aquatic animals including many types of corals, sponges, crinoids,
bryozoans, alcyonarians and oysters.

LOCATION, SIZE, CONDITION AND CONSERVATION STATUS
NGM

Few hard bottom and oceanic reefs are known to occur in state
jurisdictional waters. Only small, isolated patches of lag deposits
composed of shell and rock gravel are found off the barrier islands.
Most hard bottoms are primarily found in deeper waters on the
mid- and outer continental shelf.

The high popularity of oceanic deep sea fishing has increased the
potential for overfishing of hard bottom and oceanic reef areas.
Oil exploration in the vicinity increases the potential of exposure
of these areas to pollution and disturbances and physical damage to bottom dwelling species, including
delicate coral formations.

15.2 Hard Bottoms and Oceanic Reefs

Range of Hard Bottoms and Oceanic Reefs