OYSTER BEDS OF JAMES RIVER, VIRGINIA. 11 



Department of Commerce and Labor. 



BUREAU OF FISHERIES. 



Field record of examinations of oyster beds. 



General locality : James River. 



Local name of oyster ground: Between Rock wharf and Spindle rock. 



Date: August 28, 1909. Time: 9.25 a. m. 



Angle: F. 140. Buoy No.: 23. 



Depth: 7 feet. Bottom: Hard. 



Condition of water: Medium clear. 



Density : Temperature: 



Current : Stage of tide : 



Tongman: Lawrence, inflatboat. 



No. grabs made: 8. ■ Tongs: 14 feet. 



Total area covered; 3\ square yards . . 



r-1 in.: 27. 1 in.— X in.: 69. 



No. oysters taken:| x ^ _ 4 Jn . 1Q 4 ^ . ^ 



Quantity shells: J bushel. 



{Spat per square yard: 7.7. 

 Culls per square yard: 19.7 . 

 Counts per square yard: 3.7. 



X in.=cull limit prescribed by law. 



This furnishes an exact statement of the condition of the bed at a 

 spot which can be platted on the chart with error in position of not 

 more than a few yards. From the data obtained a close estimate 

 may be formed of the bushels of oysters and shells per acre in the 

 vicinity of the examination and ; by multiplying the observations, 

 for the bed as a whole. In the course of the survey 590 observations 

 were made at various places, principally on the natural rocks, but 

 some on the barren bottoms also. 



In former surveys by the Bureau the relative density of the oyster 

 growth has been considered solely from the standpoint of the total 

 quantity of oysters. That method is satisfactory where the depth 

 is fairly uniform throughout the region examined, but was not con- 

 sidered accurate enough for the purposes of the present report. 



With a given quantity of oysters per square yard or acre, a bed 

 lying in shoal water is more valuable commercially than one in deep 

 water, owing to the fact that the labor of the tonger is more efficient 

 in the former. As has been pointed out, the area covered by a "gra b " 

 decreases with an increase in depth, and, moreover, the deeper the 

 water the greater is the labor involved in making the "grab" and 

 the smaller is the number of grabs which can bo made per hour or 

 per day. With 14-foot tongs used from a canoe, such as is employed 



