Page:Popular Science Monthly Volume 20.djvu/49

Rh mature oysters was found to be considerably larger than that on the unworked beds, and there was thus, apparently, a much increased production upon the former areas, or the ratio apparently indicated that, instead of deteriorating, the beds were improving, though all other indications were the reverse.

It is evident that, if the number of young growth falls below the number of mature oysters, the fecundity of the bed is impaired; but it does not follow that, if the young greatly outnumber the mature, it is a sign of increased production, for, though the ratio may be increased by increasing the antecedent, or the number of young, it may also be increased by diminishing the consequent, or number of mature oysters. We know that from the beds in question many millions of oysters are annually removed, and that a large percentage of them are mature; and, if this removal of one class is excessive, it might show itself in the increased ratio of young oysters to mature. Supposing this to be the case, the young would then greatly outnumber the mature for about three years, or the period necessary to pass from youth to maturity. During this period there is a constant removal of the brood-oysters, and, as the reproduction depends upon them principally, the number of young spawned during that period will constantly decrease, so that at the end of three years the mature oysters would probably outnumber the young, and the ratio be as abnormally small as it was abnormally large. Now, with the large number of mature oysters there would be an increased production, and at the end of the second period of three years the ratio would again change, and in this way will increase and diminish alternately, while the number of oysters will constantly diminish. In time, however, the brood-oysters will become so scarce and so widely separated that the fertilization of the eggs will be more and more improbable, and the young will consequently remain in the minority, and, the fishing continuing, the entire destruction of the breeding power will be but a matter of time.

During both seasons of the investigation of the question here discussed, every effort was made to collect statistics of the oyster-fishery, and from these statistics has been estimated the number of oysters removed in a day and in the season. In 1878 this number was over 1,500,000 per day; in 1879, over 700,000 per day. In the sounds the dredging continues throughout the year, though comparatively little is done during the summer months. As the law sanctions the working of the beds only from October 1st until May 1st, in order that any error may be in under-rather than in over-estimation, I will consider the dredging to be confined to that period, and will make the very liberal allowance of three days in each week for bad weather which would prevent work. The dredging-season would then be one of one hundred and twenty days, and in that time there would be removed from the beds, by the estimate of 1878, over