62 U. S. BUREAU OF FISHERIES 



Sound, Turtle River, Jek}^ Creek, St. Andrew Sound, Cumberland 

 Kiver, Brickhill River, Cumberland Sound, and St. Marys River. 



The program of observations consisted of examination of the 

 bottoms and determinations of temperature, salinity, hydrogen-ion 

 concentration of the water, and of the amount of material suspended 

 in it. The results of the survey served as a basis for outlining a 

 series of recommeniUitions concerning the management and develop- 

 ment of the natuial oyster reefs. In order to obtain a better under- 

 standing of the local conditions ati'ecting the life of the oyster, it 

 was deemed desirable to extend observations throughout the spawn- 

 ing and setting season. In the sunnner of 1928 Dr. J. H. Weatherby, 

 temporary assistant, was assigned to field work in the vicinity of 

 Doboy Island. Under the supervision of the senior author and in 

 cooperation with the State department of game and Hsh he carried 

 out a program of observations and ma<le experiments on spawning 

 and setting of oysters. In April, 1929, Dr. R. H. Luce visited 

 l)ol)oy Tshmd to examine the spat collectors which were placed there 

 (lui-ing the pi-eceding summer and to make some additional observa- 

 tions on tidal currents. 



It is the autliors' desire to acknowledge tlie cooperation of the 

 State department of game and fish and to express their gratitude 

 to Peter S. Twitty, commissioner, and R. W. Clancy and J. F. 

 Seegers, tidewater commissioners, for help and interest in this work. 



PHYSIOGRAPHY OF THE COASTAL REGION 



The oyster-producing bottoms of Georgia are entirely confined to 

 tlie coastal i-egion, whicli consists of numerous sounds, estuaries, and 

 of a network of tortuous rivers and creeks connecting with each other 

 and siMioiinding low and uninhabitable mai'shlands. Due to recent 

 (from Ihe geological point of view) submergence of the coas<al low- 

 land, the mouths of (lie large riveis have been converted into estuaries 

 naxigablc by seagoing vessels from 10 to 20 miles fi-om the seacoast, 

 while small creelcs became deep tidal rivers. OAving to the low alti- 

 lude of tlie land, the sti-eams aie sluggish and (he wliole coastal plain 

 |)oorly drained. One; of the most typical characteristics of this 

 region is the salt marshes, which reach their greatest extent near the 

 mouths of large rivers. The origin of the marshland, according to 

 O. Veatch and L. W. Stephenson (1911), is attributed to the sub- 

 mergence of the coast, although silting is also considered as a con- 

 tributing factor. The whole area of the inshore watei's of Georgia 

 can be characterized by its comparative shallowness; continuous depo- 

 sition of sediment, which settles as a thick layer of soft mud on the 

 bottoms and over the tidal flats; and strong tidal currents sweeping 

 the tidal rivers and creeks. From an ecological point of view, the 

 waters of this region may be divided into three classes, as follows: 

 (a) Open sounds, (h) rivers, (e) small creeks and marshes. 



OPEN SOUNDS 



rSt. Andrews, St. Simon, Altainaha, Doboy, Sapelo, St. Catlicrino, Ossabaw, Wassaw. See 



figs. 1 and 2] 



The sounds are large bodies of water varying from 1 to 2 miles in 

 width at their mouths and extending several miles inland. On their 

 eastern sides they are directly connected with the ocean, although 



