society if 

 rather than 

 food value. 



they are 

 harvested 



left undisturbed, 

 for their limited 



6.2 MANAGEMENT IMPLICATIONS AND GUIDELINES 



Clearly, the oyster reef component of 

 the coastal ecosystem in the Southeastern 

 United States depends on a healthy marsh- 

 estuarine environment. Thus, the most 

 logical recommendation for reef management 

 is to mitigate increasing man-induced 

 alterations on the marsh system to the 

 extent possible. Changes in water flow, 

 both surface and subsurface, appear to 

 cause the most far reaching and cumulative 

 damage to the entire system, and thus 

 indirectly to the reef subsystem. See 

 Table 1 for a summary of cultural stress 

 on oysters. 



The maintenance of high water quality 

 is, of course, important to the continued 

 viability of oyster reefs; and the intro- 

 duction of urban, industrial, and agricul- 

 tural pollutants from both point and non- 

 point sources is to be avoided. Subtidal 

 oysters normally can tolerate a fair 

 amount of insult in terms of poor water 

 quality before succumbing to many of the 

 common pollutants. Such oysters usually 

 become dangerous to eat before they die 

 from chemical pollution. Reef oysters, on 

 the other hand, are already stressed and 

 may not be as hardy. At present, the oys- 

 ter reef zone of the South Atlantic Bight 

 appears relatively free of toxic chemicals 

 and excess nutrients, except in the immed- 

 iate vicinity of major population centers 

 such as Savannah, Georgia, and Charleston, 

 South Carolina. 



Long-term effects of increasing 

 freshwater pumping may pose a problem more 

 serious than pollution for the marsh oys- 

 ter reef system. Therefore, future urban, 

 industrial, and agricultural requirements 

 for freshwater need to be examined and 

 their long-term effects on salinity dis- 

 tribution predicted, in order to under- 

 stand the implications of development for 

 the entire coastal ecosystem. 



There have been several proposals and 

 attempts to increase oyster reef area 

 locally by spreading cultch along the 

 fringe between marsh and water to induce 

 oyster settlement. These efforts have 

 been largely unsuccessful, implying that 

 our thesis is valid; that is, the distri- 

 bution of reefs relates to a specific set 

 of conditions, especially with respect to 

 water flow, and the proportion of a marsh 

 drainage unit occupied by oyster reefs is 

 not indefinitely expandable. The guide- 

 line derived from these observations is 

 that artificial oyster reef development 

 should be seriously attempted only at 

 former reef sites. 



In conclusion, the intertidal oyster 

 reef subunit of the marsh estuarine eco- 

 system is an important component of the 

 coastal zone in the Southeastern United 

 States, and this subunit has declined in 

 total area during the last 90 years. We 

 can only guess at the consequences of the 

 continued loss of reef area, but these 

 effects could be both obvious and subtle, 

 and could definitely result in an ecosys- 

 tem less healthy, rich, and productive, 

 and certainly less interesting from an 

 aesthetic point of view. 



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