THE OYSTER AND THE OYSTER INDUSTRY. 33 



of that locality. These inshore beds are practically exhausted now, 

 and dependence is being placed for set upon the oj^sters planted in 

 deeper water offshore. The deeper water warms up slowly, and the 

 oysters spawn so late that the crest of the warm season is over 

 before setting occurs and ver}^ little set is obtained from them. In 

 Long Island Sound spawning beds should be placed in the shallow 

 inshore waters to take the place of the original natural })eds. Cultch 

 beds should be placed where they have been heretofore, outside or 

 in the lower part of the mouths of rivers outside or alongside the 

 oyster beds. 



In this connection, as stated earlier, the fact that certain waters 

 are contaminated with factory trade wastes must be borne in mind. 

 It has been found that the upper waters of certain harbors in Long 

 Island Sound contain such a concentration of trade wastes that 

 oyster larvae are at once killed by it. No adult oysters are now 

 found in such waters. As these wastes are carried out nearer to 

 the mouths of the harbors they are diluted and are at least not so 

 immediately fatal to the oysters, but ultimately the effect is cer- 

 tainly harmful. Some of the wastes also probably contribute to 

 the green discoloration of the meats of oysters found in certain beds. 

 Vigorous efforts should be made to require the reclamation of trade 

 wastes by the factories and to prevent their discharge into waters 

 otherwise fitted for the maintenance of sea-foods. 



General desirahility of planting cultch. — The method of oyster 

 culture by means of catching set on planted cultch is the most 

 promising one at present. Small seed oysters may be placed on 

 bottoms where, due to improved conditions, they will grow faster, 

 acquire a more desirable shape, and thus bring a better price. But 

 by putting down cultch in places where there was none before set 

 may be caught which otherwise would have perished. By this 

 method the actual number of oysters in increased. This method 

 should bo developed further in some such manner as suggested above 

 and brought into more general use. 



At several points on the Atlantic and Gulf coasts no cultch is 

 planted, the shells being burned for lime or used in building roads. 

 In some of these places the oyster beds are becoming seriously 

 depleted. This is especially true of Chesapeake Bay. Investiga- 

 tions carried on there by the LTnited States Bureau cf Fisheries 

 during 1919 showed that, while there were abundant free-swimming 

 larvas during the spawning season, the vast majority of these perished 

 from lack of cultch upon w-liich to attacli themselves. It would 

 seem highly desirable to cease disposing of the sliells for lime or road 

 building and to clean up the oyster bottoms and plant the shells on 

 them to catch set. The general improvement of the oyster beds and 

 the consequent increase in revenue from them would far outweigh 

 the relatively small amount now received for the shells as at present 

 handled. 



PLANTING SEED OYSTERS. 



In the method of oyster culture by planting seed the start is made 

 with small or "seed" oysters instead of shells. Such seed oysters 

 may vary in size from set of a few months' growth, about the size 

 of one's finger nail, to oysters of nearly marketable size in some cases. 



