taking place— 10,205 ha (25,216 acres) per year according to Gagliano (1981). The actual 

 rate of habitat loss may be greater than these calculations indicate, as these figures may 

 not include wetlands removed from their historic use because of drain and fill activities, 

 and it may not include vast areas surrounded by hurricane protection levees, road beds or 

 other structures which essentially block off or disrupt drainage patterns. This separation 

 of wetlands inhibits the flow of nutrients and aquatic life from one system to another 

 end, therefore, that area of marsh is lost for any significant contribution to fishery 

 production. Additionally, the land loss rates do not include areas which cannot be 

 exploited for living resources because of pollution. For instance, the State Health 

 Department prohibits the harvest of oysters east of the Mississippi River in areas which 

 are exposed directly to Mississippi River waters from siphons and other water control 

 structures. 



Society is irreversibly committed to the protection of life and property by 

 maintaining levees along the Mississippi and other rivers. Therefore, efforts to build new 

 lands are basically limited to controlled freshwater introduction from the rivers at 

 selected sites. The overall effects need to be carefully projected and evaluated in 

 advance because such effects could be more damaging than beneficial. Even if the rivers 

 were allowed to seek natural courses, the present sediment load would not be adequate to 

 compensate for land loss rates due to the trapping of sediments by impoundments 

 upstream. It required approximately 6,000 years to form Louisiana's coastal area by 

 natural processes. If the present coastal area is considered to be 2,400,000 ha (6,000,000 

 acres) of land and shallow water bodies then the accretion rate for the past 6,000 years 

 was 400 ha (1,000 acres) per year. We are presently losing coastal wetlands at the rate 

 of 10,205 ha per year (Gagliano 1981). Therefore, natural accretion rates would not be 

 adequate to maintain our coastal area. It is obviously misleading to calculate accretion 

 rates over a 6,000-year period, but any way the numbers game is played, the task of 

 appreciably reducing present land loss rates is monumental. 



In addition to having only limited resources to build new land, we are also limited in 

 protecting existing wetlands as many of the forces and processes which reduce the 

 coastal land area are not presently controllable. The freeze of 1961-62 resulted in the 

 destruction of the black mangroves, large fish kills, reduced oyster harvest, and the 1962 

 shrimp harvest was one of the lowest of record. The impact of this freeze, which formed 

 ice in the lower part of Barataria Bay, was short-lived on the animal population. It took 

 approximately 7 years for the black mangroves to come back, however. These mangroves 

 are important to the area as they reduce erosion and aid in land building by trapping 

 sediments in their root systems. The passage of hurricane "Betsy" in 1965 resulted in the 

 immediate loss of entire islands and caused hundreds of feet of coastline and shoreline 

 recession. Uncontrollable natural subsidence also is a major factor in land loss. To a 

 limited extent, subsidence due to mineral extraction is controllable. 



FISHERIES MANAGEMENT OPTIONS 



Any proposed use of large amounts of river water for land building should be 

 carefully considered. The reduction of the discharge of fresh water at the river mouth 

 may affect biological processes in the adjacent estuaries and the nearshore Gulf of 

 Mexico. Spawning and migration patterns may be severely impacted if the flow of the 

 river is altered. 



Fishermen should take an interest in efforts to maintain our coast as the industry 



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