to restore or protect wetlands and estuaries must be understood, consequently the 

 processes which support productivity must also be understood. Correlations between 

 wetland characteristics and natural resource production provide an indication of the 

 overall relationships, but more detailed information on actual processes is required. 

 This requires experimental approaches to marsh ecology. Improved cooperation 

 from fisherman and other natural resource harvesters, who are often reluctant to 

 provide detailed information on their harvests, offers the potential of extensive and 

 meaningful data if treated properly. 



The changes in Louisiana's coastal environments provide an experiment on a 

 very large scale, which can provide insight to the relationship of wetlands and 

 natural resource production. If this can be combined with sufficient long-term 

 support of scientific enterprises to describe processes in detail, sound natural 

 resource management strategies may result. 



James Gosselink: In the Calcasieu estuary where wetland loss has been rapid, inshore 

 shrimp yields have increased. How can this be interpreted? 



Barney Barrett: Erosion and saltwater intrusion may in the short run increase shrimp 

 production by increasing the area of nursery grounds with salinity above 10 ppt. 

 Calcasieu Lake is somewhat saltier than it was years ago, but, as marsh habitat loss 

 proceeds, shrimp production will decline. 



Eugene Turner: The inshore yield is a fairly constant proportion of the total catch 

 (including the offshore catch) on a statewide basis. Thus the inshore catch statistics 

 in the Calcasieu estuary are probably also representative of the contribution of the 

 estuary to the offshore catch. In the Calcasieu estuary, freshwater has been 

 diverted to rice fields, causing an increase in salinity, and consequently short-term 

 increases in shrimp yield. Fishing effort has also increased. 



James Gosselink: Is fossil peat, released by wetland erosion, important as a food source? 



Eugene Turner: Natural channels are continuously reworked and release peat. I do not 

 think that the accelerated wetland loss causes a great increase in peat released. 



John Teal: Organic matter which accumulates in marsh sediments below the top few 

 millimeters is quite resistent to degradation and I doubt that it is an important food 

 source. 



Donald Boesch: For particular important fishery species such as shrimp, we can relate 

 production to a number of variables, such as the area of saline marsh, the amount of 

 natural marsh edge, mixture of open water and marsh, and critical temperature 

 conditions. Do we satisfactorily know what these optimum conditions are for any 

 particular species? If not, what do we need to know? 



Barney Barrett: The brackish zone of the marsh estuaries is being compressed and 

 reduced. This may result in a series of rather salty estuaries extending to the 

 Intracoastal Waterway and an abrupt transition to freshwater. The objective is to 

 maintain a broad brackish habitat rather than management for a particular fishery 

 species. 



Donald Boesch: Limiting considerations to one species for the moment, couldn't the 



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