SOME CONSEQUENCES OF WETLAND MODIFICATION 

 TO LOUISIANA'S FISHERIES 



Barney Barrett 



Louisiana Department of Wildlife and Fisheries 



Box 14526 



Baton Rouge, LA 70898 



ABSTRACT 



Agencies of State and Federal Governments as well as local interests have long 

 recognized that Louisiana's wetlands are undergoing adverse ecological changes. These 

 changes are the result of both natural processes and the works of man. 



The dominant ecological change taking place in the coastal area is habitat 

 alteration— wetlands are eroded and replaced by water. Now there are many proposals to 

 reduce erosion rates which include freshwater introduction, jetties, and additional 

 restrictions on activities. 



Freshwater introduction may be the most efficient means of reducing land loss 

 rates. Fresh water, particularly from the Mississippi River, would reduce saltwater 

 intrusion and contribute nutrients and sediments to the estuaries and wetlands. Changes 

 in water regimes, however, could drastically alter animal populations as occurred in 

 Sabine Lake. The water cycle was changed by the construction of the Toledo Bend 

 reservoir and dam which resulted in a drastic reduction in shrimp harvest in this lake. 



RECOGNITION OF THE PROBLEM 



We are not just learning about land loss. There was a realization that flood control 

 projects on the lower Mississippi River were causing adverse ecological changes prior to 

 oil and gas activity in south Louisiana. With the leveeing of the Mississippi River along 

 with industrial development and its accompanying channelization and dredging, the 

 problem was intensified and the rate of habitat destruction increased. 



The Louisiana Wildlife and Fisheries Commission and its predecessors, as well as 

 the affected parishes and other local interests, have recommended repeatedly, since as 

 early as 1900, that Mississippi River water be directed into adjacent subdelta marshes to 

 maintain habitat. 



U.S. Fish and Wildlife Service (1959) stated "Loss of fertility, formerly maintained 

 at a high level by overflow water from the Mississippi River is reducing the value of the 

 subdelta marshes as nursery and rearing grounds for all fish and wildlife forms". These 

 observations made 22 years ago remain true today. 



The problem of land loss is much more serious today because of the rate of loss now 



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