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Why Save
Dauphin Island (including the West End)
Commercial & Recreational Fishing Industry
As a barrier island, Dauphin Island contributes to the
formation and maintenance of one of the largest and most important
estuarine complexes occurring along the northern Gulf of Mexico. Mississippi Sound and its associated bays and tidal creeks and bayous
extending from Mobile Bay to Louisiana is totally dependent upon Dauphin
Island and its sister barrier islands in Mississippi. Dauphin Island
separates the eastern third of Mississippi Sound and Mobile Bay from the
Gulf of Mexico. This separation, which evolved over thousands of years,
created Mississippi Sound and is the singular causative factor for its
high productivity and value as an estuary.
In addition to shielding over 10,000 acres of mainland salt marshes from
the force of the open waves of the Gulf of Mexico, the physical barrier
created by Dauphin Island allows the mixing and dilution of higher
salinity Gulf waters with the fresh water discharges of the mainland
rivers. The dilution in salinity creates the estuarine conditions that
are essential to shrimp, crab, oyster, and finfish production.
Oystermen in Mississippi Sound
Mobile Bay and Mississippi Sound estuaries provide essential estuarine
nursery habitat that is critical for the existence of an estimated 98
percent of the commercially and recreationally important species pursued
in the Gulf of Mexico. Dauphin Island’s surf zone beaches provide
feeding habitat for the federally listed threatened piping plover (Charandrius
melodus), while the beach and dune areas provide nesting habitat for
the endangered least tern (Sterna antillarum). Three listed
sea
turtles (threatened loggerhead (Caretta caretta), threatened green (Chelonia
mydas), and endangered Kemp’s ridley (Lepidochelys kempii)
also utilize the waters surrounding the island and occasionally nest on
the island’s beaches.
During the decade between 2000 and 2009, a number of hurricanes and
tropical storms devastated the shoreline of Dauphin Island. The western
end of the island has been most affected by these storms. In August
2004, Hurricane Ivan created a breach in the Dauphin Island that was
widened to over one mile by Hurricane Katrina in 2005. Subsequent winter
storms continue to maintain the width of the breach and prevent it from
filling in naturally. The land lost in the path of the breach represents
shore habitat no longer available for the above listed endangered and
threatened species for feeding or nesting purposes.
The "Katrina Cut"
(click photo to enlarge)
The breach now allows the higher salinity Gulf of Mexico waters to enter
Mississippi Sound and Mobile Bay much farther east than the traditional
entry point in the pass between Dauphin Island and Petit Bois. This has
altered the salinity regime of Alabama’s portion of Mississippi Sound
and led to the death of Alabama’s largest and most important historic
oyster reefs in the vicinity of Cedar Point where The Mississippi Sound
and Mobile Bay join.
Salinity Levels at Cedar Point
Before Hurricane Katrina, the oyster reefs of eastern Mississippi Sound
and western Mobile Bay were among the most valuable and productive
natural reefs in the nation. In the past, as many as 600 fishermen have
made a living catching oyster on these reefs. Since Katrina, these reefs
have essentially ceased to produce oysters because of the greatly
increased salinity levels over the oyster reefs allowed predatory marine
snails to invade the reefs.
Oyster Drills
These marine snails have consumed all the
oysters that were growing on these reefs and will continue to devastate
the reefs as long as the salinity remains out of balance in lower Mobile
Bay and Mississippi Sound.
Reduction in average pounds of oyster
meat per trip after Katrina
Many of the fishermen who used to work the
reefs have had to pursue alternative sources of employment.
Historic photo of oystermen in Mobile Bay &
Mississippi Sound
Most of the
oysters now opened in the many oyster houses in Mobile County are
shipped in from Mississippi and Louisiana and occasionally from as far
away as Texas!
While the damage inflicted upon the oyster reefs by the
increased salinity levels is complete and obvious, what is not clear to
date is what the impacts on the other estuarine dependent species will
be over the long term if these conditions continue to prevail in
Mississippi Sound. The demise of the oyster industry may be an indicator
of what is in the future for Alabama’s Mobile County coastline if
Dauphin Island is allowed to continue to erode.
Alabama's Principal Oyster Reefs
(click photo to enlarge)
Restoring the island and filling in the
Katrina Cut will help to mitigate damage to the fishing industry in the
Sound.
Related Links
More Reasons to Save Dauphin
Island
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