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CHAPTER IV: WILDLIFE HABITATS FOR MISSISSIPPI’S SGCN,

THREATS AND CONSERVATION ACTIONS^273

animals. Weather events, water depth, temperature, salinity, turbidity, nutrient availability,
accumulation of heavy metals and substrate type are factors affecting oyster growth. They generally
prefer moderate levels of nutrients, temperature, etc., for proper growth. Large fluctuations in salinity
can lead to die-off. Oyster reefs create habitat and shelter that is beneficial to hundreds of other species.

LOCATION, SIZE, CONDITION AND CONSERVATION STATUS
NGM

Mollusk reefs are found in small and large patches on the
Mississippi Sound bottom and in the bays along the coast of the
mainland. Some of them have been created by seeding of
additional shell. Oysters prefer moderately saline waters and are
exposed to additional predators when salinity rises significantly.
Oyster reef acreage is estimated to be approximately 10,000 to
12,000 acres and has increased slightly over the past two decades.
According to the Mississippi Department of Marine Resources,
about 7,400 acres are located in the western Mississippi Sound, and the remainder are uncharted or
hidden reefs. The MDMR has planted over 1,000 acres of oysters from 1997 - 2005. Productive oyster
reefs are dependent on water quality.

Pollution that enters the Sound is detrimental to the viability of the oyster reefs. With the increases in
population in the coastal urban areas, there is an increased potential for an increased level of pollutants
and nutrients in the water. Oyster harvesters are major advocates for improving water quality of the
Sound.

Mollusk reefs are vulnerable in the state due to the increased potential for pollutants in coastal waters.

SPECIES OF GREATEST CONSERVATION NEED ASSOCIATED WITH
MOLLUSK REEFS

GROUP SCIENTIFIC NAME COMMON NAME TIER
Birds Haematopus palliatus American Oystercatcher 1
Calidris canutus Red Knot 2
Eudocimus albus White Ibis 2
Calidris alpina Dunlin 3
Calidris mauri Western Sandpiper 3
Reptiles Malaclemys terrapin pileata Mississippi Diamondback Terrapin 2

THREATS TO MOLLUSK REEF COMMUNITIES

Incompatible Water Quality high
Channel Modification high

14.7 Mollusk Reefs

Range of Mollusk Reefs