REVIEW AND RECOMMENDATIONS 



The major portion of the Texas-Louisiana shelf is presented as a 

 reasonably discrete ecosystem, with the Mississippi River representing a 

 dominant environmental force. The system is characterized by two major 

 soft-bottom assemblages, each containing a highly-prized and 

 commercially valuable species of penaeid shrimp. The pelagic community 

 of the system contains few species which support commercial fisheries. 

 The system is characterized by the presence of more artificial reef 

 communities than any other shelf area of the United States (perhaps the 

 world), and these reef habitats support recreational and commercial 

 fisheries for species such as snapper and grouper. Some of the 

 hermatypic coral reefs represented in the system are considered to be 

 among the more valuable communities for the reason of uniqueness rather 

 than commercial importance. 



The information which is available for the Texas-Louisiana shelf 

 ecosystem is largely descriptive. Structure of the system has been 

 reasonably well-defined, and several large scale investigations dating 

 from the early 1960's provide information characterizing annual 

 variability in environmental attributes as well as abundance of dominant 

 and/or valuable species. Recent information describing species 

 composition and abundance of demersal epifauna compares favorably to 

 descriptions obtained some four decades past. 



Little information is available describing the processes which 

 govern the fluctuations in abundance or status of important shelf 

 species. The methodologies required to provide such information are 

 only beginning to emerge. Given the overwhelming influence of the 

 Mississippi River and its contaminant loads, many studies have been 

 unsuccessful in delimiting effects of specific activities such as 

 petroleum development from effects caused by natural forces, and the 

 reductionist nature of most of the ongoing large investigative programs 

 suggests that very little will be contributed in this regard in the near 

 future. More information is needed regarding important processes to (1) 

 be able to evaluate the results of man's activities vs. natural 

 variations, and (2) estimate the assimilative capacity of the 

 Texas- Louisiana shelf ecosystem as a recipient of man's waste products. 



The estimate of the assimilative capacity of the Texas-Louisiana 

 shelf should attempt to define how many increments of the total capacity 

 are available for additional activities (or users) in light of the 

 increments already being used by the natural system and existing 

 activities. Examples of the existing users of say, dissolved oxygen, 



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