The uniformity in water density at any given time is due to the 

 thorough mixing of water in the shallow basin of Mississippi Sound. 

 Thus it is possible to utilize the average salinity of all stations 

 in studying the changes in the area over a period of time. Data 

 are presented in Fig, 4 to show the trend in salinity levels during 

 the period December, 1948 to Tune, 1949. These figures represent 

 the average of the bottom salinities of all stations in each area. 

 The water was fresh most of the time between February and Hay , 

 although essentially no water was entering the area from the Bonnet 

 Carre Spillway according to the Corp of Engineers, U. S. Army, 



The same treatment of the data for Area III in Lake Mechant 

 does not provide as accurate a picture of salinity conditions in 

 the lakes. Here, the major influx of fresh water is at the northern 

 end of Station 20, From this point, a gradual mixing with salt water 

 takes place along the north-south axis and maximxim water densities are 

 found at the southernmost point, Station 23, 



The data in Table 6 were collected when the tide was theoretically 

 at 1/4 flood* Actually, at this time there was essentially no tidal 

 flow. 



In Area I, salinities generally averaged above 5 ppm and were at 

 some times and at some stations as high as 18.6 ppn. The variations, 

 however, were so great that the average values do not present an 

 Hccurate picture of the trend during the period of the surveys. 



Summary of Field and Experimental Data 



The pertinent conclusions which may be derived from the data 

 collected in this study may be briefly stated at this point to 

 advantage. 



Area I . The groirth, mortality and condition of the oysters 

 in this section of Mississippi Sound indicate that in early spring 

 the salinity levels were minimal for the support of the populations. 

 These conditions started to Improve late in April and by the middle 

 of May a normal environment for growth and reproduction was attained. 



Area II , The gro^rth, mortality and quality of oysters in the 

 west end of Mississippi Sound indicate that this environment was 

 extremely unfavorable. There was no evidence that Internal otf ex- 

 ternal parasites were present in sufficiently large numbers to 

 affect the oysters seriously. The physical factors in the en- 

 vironment such as tonperature, turbidity and pH were within the 

 range found in other localities where oysters thrive. Trans- 

 plantation of these oysters to other areas demonstrated that 



21 



