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 there- 
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. 
