OYSTER BEDS OF JAMES RIVER, VIRGINIA. 59 



not only is the area covered by a "grab" smaller, but, other things 

 being equal, fewer " grabs" can be made in an hour than in a smaller 

 depth. 



In the tables shown in this report and on the chart these factors 

 have all been considered in estimating the relative density of the 

 beds. In the estimation of the available contents of the rocks 

 as exhibited in the following tables the same factors have been con- 

 sidered. It is assumed that, at the price which has recently been 

 received for market oysters in the region under consideration — 

 namely, 45 cents per bushel — it would be wholly unprofitable to 

 tong on bottoms which would yield less than 3 bushels of culled oysters 

 per day, exclusive of the time spent in culling, which would ordi- 

 narily involve part of the time of a second man or boy. In the same 

 way at the price of seed oysters, namely 30 cents per bushel, it is 

 assumed to be equally unprofitable to tong on bottoms yielding less 

 than 4 bushels, exclusive of shells. 



It can not be argued that this limit is too high, but undoubtedly 

 it will be claimed by some that it is entirely too low. The objection 

 would be well founded if it were to apply wholly to areas on which 

 the initial density of growth was such as to afford the minimum yield 

 adopted, but it will not lie against the application of the standard to 

 areas of greater initial productiveness. A dense bed in course of 

 partial denudation by tonging is not uniformly depleted over its whole 

 area. The tongers spread themselves more or less promiscuously 

 over the rocks and take up practically all of the oysters in patches, 

 while other areas are, for the time being, inadvertently left untouched. 

 Later many of these untouched spots are tonged with profit, until the 

 worked areas become so great in proportion to those which have been 

 overlooked that the time spent in searching for the latter makes fur- 

 ther work unremunerative. At this stage of temporary abandon- 

 ment the rock consists of a few small patches of productive bottom, 

 areas which are practically bare of market oysters, and others which 

 have been worked over but still retain some oysters scattered over 

 them by the operations of tonging. It is of course impossible, from 

 the complexity and irregularity of the conditions obtaining on an 

 oyster bed, to fix a limit of more than reasonable accuracy. In pre- 

 paring the following tables the present available productiveness of 

 each area has been considered with regard to the terms of its initial 

 yield to the tonger and its total estimated contents above that which 

 would give a return of 3 bushels per day's work on the market oyster 

 beds and 4 bushels on the seed beds. The depleted areas and most 

 of the areas covered by what is called very scattered growth are t here- 

 fore negligible as present factors. A very few areas in the depleted 

 bottoms and a somewhat greater proportion of the bottoms bearing 

 a very scattering growth are of potential value as bearing small 

 oysters and shells which reasonably assure future regeneration. 



