It is obvious from the extensive production of shellfish and Crustacea 

 within the estuarine zones of the South Atlantic and Gulf that such 

 areas are of inestimable value. Since shellfish and Crustacea represent 

 only part of the total productivity, and when such areas are evaluated 

 from a recreational and esthetic standpoint, it is obvious that 

 estuarine areas may be the most important ecological systems that must 

 be dealt with. The management of such ecosystems is foreseen to become 

 of major importance in the ^ery near future. From the statistics 

 presented, it is apparent that there is not enough information to 

 determine the exact sites and levels of productivity for various 

 important species within the estuaries. Some of this dearth of 

 knowledge is being overcome by recent investigations and estuarine 

 inventories. Nevertheless, some system should be developed to evaluate 

 or describe specific ecological zones within the estuaries so that a 

 quantitative determination of productivity can be accomplished. 

 There is not much question that environmental impact statements which 

 on the one hand attempt to evaluate the need and economic value of 

 disruptive activities, must also include quantitative and analytical 

 measurements of the natural resource productivity if the public is 

 to offset such proposals and develop acceptable environmental management 

 plans. (A. A.) 



Keywords: shellfish, crustaceans, productivity, coastal marshes, estuaries, 

 U.S. South Atlantic and Gulf Coasts 



IV-E-2 



Idyll, C.P., D.C. Tabb, and B. Yokel. 1968. The value of estuaries to shrimp. 

 Pages 83-90 u[ J.D. Newsom, ed.. Proceedings of the marsh and estuary 

 management symposium. Louisiana State University, Baton Rouge. 



Information on the importance of estuaries is being gathered more 

 quickly and more precisely than before and it is being made available 

 to the public. The role of the estuaries is still not clear, however. 

 Relatively few estuarine animals appear to be dependent on the estuary 

 for nearly their whole life process. 



Some shrimp of the family Penaeidae, especially the genus Penaeus , 

 are good examples of the use of estuaries ias nursery grounds. A 

 considerable amount of information is available concerning the numbers, 

 sizes, and other characteristics of shrimp at the edge of the estuary, 

 either entering or leaving. Much less is known about the shrimp 

 during their residence in the estuary itself. 



The advantages to shrimp of residence in an estuary during the young 

 stages appear to be of two kinds. In the first place the estuary 

 provides a rich feeding ground. The other advantage is protection 

 from predators and competitors. 



178 



