VI-107 



j large populations of certain unicellular green algae which appear to 

 be as suitable for food as other green algae on which they thrive. 



J There needs to be more definitive work done on the actual sources of 



1 



food used by various estuarine organisms, oarticularly those of com- 

 mercial importance, as well as the specific kinds of food. We need 

 to know how much of the diet of the given species comes from a given 

 source. This is narticularly true for the detritus feeders. We need 



to know how much detritus eaten comes from salt marshes; how much 



I 



from freshwater sources up-river; how much from submerged aquatic 



vegetation; and how much from other sources. Better knowledge in 

 this area is necessary in order to make intelligent decisions about 

 how much of a given sort of habitat is necessary to "carry" a given 

 level of resource. A better understanding and more knowledge of car- 

 bon fixation by plants in estuaries is necessary, for this is the 

 basic source of all food for all levels of animals in the estuary. 



The Estuary as a Nursery 



We need to identify what is in the estuarine environment that makes 

 it so suitable a nursery for larval and juvenile animals. This in 

 turn means identifying, among other things, individual steos in food 

 webs. Enough aspects should be investigated to allow us to make 

 estimates of energy turnover. We already know that ocean basins are 

 nutrient traps - olaces where energy is traoced and not returned to 

 the cycle. What is the role of estuaries in this "running down" 

 process? Do fine sediments act as traps for organic and inorganic 



