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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 Islandís 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 Kempís ridley (Lepidochelys kempii) also utilize the waters surrounding the island and occasionally nest on the islandís 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 Alabamaís portion of Mississippi Sound and led to the death of Alabamaís 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 Alabamaís 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.

 


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UPDATE ON KATRINA CUT


After the BP Oil Spill of April 2010, the Katrina Cut was closed with rocks and other material by the Army Corps of Engineers, in an effort to protect the mainland coast and the salt marshes in the Mississippi Sound from oil contamination.  An added benefit of this project was to help combat over-salination in the Sound, which had been present since the island was breached in that location by Hurricane Katrina in 2005.

 

 

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More Reasons to Save Dauphin Island

 

 

 

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